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The role of legislation in driving good occupational health and safety
management systems A comparison of prescriptive and performance
based legislation
Jeong-ah Kim Bachelor of Health Science (Nursing)
Master of Public Health
A thesis submitted for the degree of Doctor of Philosophy
Centre for Public Health Research
Queensland University of Technology
November 2004
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Abstract
Countries seek to control exposure to hazardous substances and
environments by the enactment of legislation. In the past thirty years,
two major different approaches to occupational health and safety
legislation have been devleoped by countries around the world. The
performance-based legislative approach has been linked with the
emergence of occupational health and safety management systems
but no research has previously been done to determine whether or not
the legislative approach taken by government influences the
introduction or form of occupational health and safety management
systems used by organisations. Similarly, although the reasons why
Australia and other countries have moved to performance-based
legislation have been explained in terms of social, political and
economic factors that influenced the change, little research has been
done on the effectiveness of this approach compared with the
prescriptive approach of countries such as Korea.
The overall aim of this research is to develop a conprehensive
understanding of the management of expusre to heavy metals in
selected industries in Korea and Australia. The specific objectives of
the study are to determine:
The effectiveness of heavy metal exposure management in the
fluorescent lamp manufacturing industry in Korea, and an Oral
Health Service, and lead-risk workplaces in Queensland,
Australia;
The management of the legislative arrangements for health
surveillance in Korea and Queensland, Australia;
The characteristics of the occupational health and safety
management systems that are in use in the heavy metal
industries in Korea in Australia; and
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The effectiveness of prescriptive and performance based
legislative systems in protecting the health and safety of
workers in heavy metal based industries.
Secondary analysis of biological monitoring data from 6 fluorescent
lamp manufacturing companies (8 workplaces) in Korea was used to
examine the extent of mercury exposure and the effectiveness of the
health surveillance system in that country. A survey of dental workers
in an oral health service in Queensland provided data on the extent of
mercury exposure to the workforce and workers’ attitudes to the
management of occupational risks. The efficiency of the lead health
surveillance in Queensland was examined by way of a questionnaire
survey of lead designated doctors in the state. A survey of registered
lead-risk companies and the oral health servies in Queensland, and 5
of the fluorescent lamp manufacturing companies in Korea provided
data on the occupational health and safety management systems in
place in these organisations.
The health surveillance system for mercury exposed workers in Korea
was found to have reduced the incidence of workers with biological
levels of mercury above the Baseline Level from 14% in 1994 to 7% in
1999. Bilogical testing of dental workers in Queensland discovered no
workers with biological levels of mercury approaching the Baseline
Level and air monitoring failed to locate any areas where workers were
likely to be exposed to levels approaching the Workplace Exposure
Standard. The staff of the Oral Health Service were generally aware of
the occupational health and safety management systems in place but
only 43% felt that mercury management in the workplace effectively
prevented exposure.
The lead surveillance system in Queensland was found to be
inadequately managed with approximately 37% of registered doctors
no longer practicing in the field and their being no way for the
government to collect reliable data on the extent of lead exposure in
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workplaces. The occupational health and safety management systems
in the companies surveyed in Queensland and Korea were found to be
influenced by the legislative arrangements in place in each of the
locations. The Korean systems were more geared to meeting the
regulatory requirements whereas the Queensland systems were
geared more towards a risk management approach. However
substantial differences were also noted depending on the size of the
organisation in each case.
Legislative arrangements in Korea and Queensland were found to
provide reasonable protection from heavy metal exposure to workers
however improvements in both systems are needed. The legislation
was also found to influence the occupational health and safety
management systems in place with performance-based legislation
producing systems having a wide risk management focus while a
narrower regulatory based focus was noted in Korea where more
prescriptive legislation is in force. A confounding factor in the nature of
the occupational health and safety management system in place is the
size of the organisation and particular attention needs to be paid to this
when legislative approaches are considered.
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Table of Contents ABSTRACT i TABLE OF CONTENTS v LIST OF FIGURES xiii LIST OF TABLES xix STATEMENT OF ORIGINALITY xxiii ACKNOWLEDGEMENTS xxv CHAPTER 1 INTRODUCTION 1 1.1 BACKGROUND 1
1.1.1 LEGISLATIVE FRAMEWORK FOR OCCUPATIONAL HEALTH AND SAFETY IN AUSTRALIA AND KOREA 1
1.1.2 THE GROWTH OF OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS 4
1.2 AIMS AND OBJECTIVES 5 1.3 OVERVIEW OF DISSERTATION 6 1.4 ETHICS APPROVAL 7 CHAPTER 2 LITERATURE REVIEW 9 2.1 INTRODUCTION 9 2.2 OCCUPATIONAL EXPOSURE TO HEAVY METALS 12
2.2.1 INTRODUCTION 12 2.2.2 WHAT IS OCCUPATIONAL HEALTH? 13
2.2.2.1 DEFINITIONS 14 2.2.3 THE EXTENT OF OCCUPATIONAL INJURY AND DISEASE 15 2.2.4 OCCUPATIONAL EXPOSURE TO MERCURY AND LEAD 20
2.2.4.1 MERCURY TOXICOLOGY 20 2.2.4.1.1 PROPERTIES OF MERCURY 20 2.2.4.1.2 ABSORPTION AND ELIMINATION OF
MERCURY 21 2.2.4.2 THE BIOLOGICAL MONITORING OF MERCURY 23
2.2.4.2.1 MERCURY IN URINE 23 2.2.4.2.2 MERCURY IN BLOOD 24 2.2.4.2.3 BIOLOGICAL EXPOSURE INDICES (BEIS) 25
2.2.4.3 AIRBORNE EXPOSURE LIMITS 25 2.2.4.3.1 RATIONALE FOR LIMITS 27
2.2.4.4 OCCUPATIONAL MERCURY EXPOSURE 28 2.2.4.4.1 OCCUPATIONAL EXPOSURE TO MERCURY
IN FLUORESCENT LAMP MANUFACTURING COMPANIES 30
2.2.4.4.2 OCCUPATIONAL EXPOSURE TO MERCURY AMALGAM IN DENTAL SERVICES 33
2.2.4.5 HEALTH IMPACTS OF MERCURY EXPOSURE 37 2.2.4.6 CONTROVERSY OF AMALGAM EXEPOSURE 39
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2.2.4.7 STUDIES OF MERCURY RELATED OCCUPATIONAL DISEASE 40
2.2.5 LEAD 41 2.2.5.1 ABSORPTION 43 2.2.5.2 DISTRIBUTION 45 2.2.5.3 ELIMINATION 45 2.2.5.4 HEALTH IMPACTS OF LEAD POISONING 46 2.2.5.5 BIOLOGICAL EXPOSURE INDICES 48 2.2.5.6 AIRBORNE EXPOSURE LIMITS 52 2.2.5.7 OCCUPATIONAL LEAD EXPOSURE 52
2.3 THE LEGISLATIVE FRAMEWORK OF OCCUPATIONAL HEALTH AND SAFETY IN KOREA AND AUSTRALIA 54 2.3.1 OCCUPATIONAL HEALTH AND SAFETY REGULATION IN
KOREA 55 2.3.1.1 HAZARDOUS SUBSTANCES LEGISLATION 59
2.3.1.1.1 SPECIFIC REQUIREMENTS 59 2.3.1.1.2 BLOOD AND URINE LEVELS FOR
MERCURY 60 2.3.1.1.3 COMPULSORY HEALTH CHECK-UP
ITEMS 61 2.3.1.1.4 OCCUPATIONAL HEALTH CHECK-UP
ITEMS 61 2.3.1.1.5 OUTCOMES 62
2.3.2 OCCUPATIONAL HEALTH AND SAFETY REGULATION IN AUSTRALIA 64 2.3.2.1 HAZARDOUS SUBSTANCES LEGISLATION 67
2.3.2.1.1 LEAD 71 2.3.2.1.2 MERCURY 75
2.3.3 COMPARISON OF AUSTRALIAN AND KOREAN LEGISLATIVE APPROACHES TO OCCUPATIONAL HEALTH AND SAFETY 76
2.4 OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS 78 2.4.1 INTRODUCTION 78 2.4.2 COMPONENTS OF AN OCCUPATIONAL HEALTH AND
SAFETY MANAGEMENT SYSTEM 81 2.4.3 HISTORICAL REVIEW OF OCCUPATIONAL HEALTH AND
SAFETY MANAGEMENT SYSTEMS 85 2.4.4 SPECIFIC HEALTH AND SAFETY SYSTEM MODELS 86
2.4.4.1 AUSTRALIAN OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS 88
2.4.4.2 ILO GUIDELINES ON OCCUPATIONAL SAFETY AND HEALTH MANAGEMENT 92
2.4.5 OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS RESEARCH 94 2.4.5.1 INDUSTRIES AND WORKPLACES IMPLEMENTING
OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS 94
2.4.5.2 MOTIVATION 95 2.4.5.3 IMPACT ON PERFORMANCE 96
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CHAPTER 3 MERCURY EXPOSURE IN FLUORESCENT LAMP MANUFACTURING COMPANIES IN KOREA 103 3.1 INTRODUCTION 103 3.2 THE PROCESS OF EPIDEMOLOGICAL DATA COLLECTION 104
3.2.1 STUDY SUBJECTS 104 3.2.2 AIR MONITORING METHODS 105
3.3 BACKGROUND 106 3.3.1 MERCURY EXPOSURE 106 3.3.2 FLUORESCENT LAMPS 107
3.4 METHOD 108 3.4.1 SOURCES AND COMPONENTS OF SECONDARY
EPIDEMIOLOGICAL DATA 108 3.5 ANALYSIS 109 3.6 RESULTS 113
3.6.1 DEMOGRAPHICS OF STUDY GROUP 113 3.6.2 INITIAL TESTS 113
3.6.2.1 RELATIONSHIP TO BASELINE LEVELS 114 3.6.2.2 RELATIONSHIP TO DIAGNOSTIC LEVELS 115 3.6.2.3 MERCURY LEVEL IN URINE AND BLOOD BY YEAR 116 3.6.2.4 GENDER COMPARISONS 119 3.6.2.5 WORKPLACE COMPARISONS 120
3.6.3 FOLLOW-UP TESTS FOR MERCURY LEVELS IN URINE AND BLOOD 128
3.6.4 COMPARISON OF FIRST AND SECOND ROUND TESTS 130 3.6.4.1 URINE AND BLOOD TESTS 130 3.6.4.2 DIAGNOSTIC LEVELS 131
3.6.5 COMPARISON OF FOLLOW-UP TESTS BY YEAR 133 3.6.5.1 DIAGNOSTIC LEVELS 133
3.6.6 REGULATORY COMPLIANCE 136 3.6.6.1 INITIAL TESTING 136 3.6.6.2 FOLLOW-UP TESTING 137
3.7 DISCUSSION 139 3.7.1 OUTLIERS 139 3.7.2 DATA 140 3.7.3 NUMBER OF TESTS PER ANNUM 141 3.7.4 GENERAL TRENDS 143 3.7.5 FOLLOW-UP TESTING 145 3.7.6 REGULATORY REQUIREMENTS IN TERMS OF HEALTH
SURVEILLANCE 147 3.8 SUMMARY 148 CHAPTER 4 MERCURY EXPOSURE IN DENTAL WORKERS IN QUEENSLAND 151
4.1 BACKGROUND 151 4.2 INTRODUCTION 152
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4.3 METHODS 154 4.3.1 RECRUITMENT OF STUDY SUBJECTS 154 4.3.2 SELF-ADMINISTERED QUESTIONNAIRE SURVEY 156 4.3.3 AIR MONITORING 158
4.3.3.1 MONITORING METHODS 158 4.3.3.2 MONITORING LOCATIONS 159
4.3.4 BIOLOGICAL MONITORING 161 4.3.5 DATA ANALYSIS 162
4.4 RESULTS 163 4.4.1 DEMOGRAPHIC CHARACTERISTICS 163
4.4.1.1 QUESTIONNAIRE SURVEY 163 4.4.1.1.1 VOLUNTEERS VS. PARTICIPANTS 163 4.4.1.1.2 EXPERIMENTAL GROUP VS.
CONTROL GROUP 165 4.4.1.1.3 GENDER CHARACTERISTICS 167
4.4.1.2 MERCURY MANAGEMENT IN THE WORKPLACE 169 4.4.1.3 OCCUPATIONAL HEALTH AND SAFETY
MANAGEMENT IN THE WORKPLACE 175 4.4.1.3.1 TRAINING 175 4.4.1.3.2 LOCAL OCCUPATIONAL HEALTH AND
SAFETY MANAGEMENT ARRANGEMENTS 177
4.4.1.3.3 RISK ASSESSMENT PROCESSES 181 4.4.1.3.4 RESOURCES 181 4.4.1.3.5 WORK-RELATED ILLNESS AND
INJURIES 187 4.4.2 AIR MONITORING 192
4.4.2.1 EXPOSURE ESTIMATES 192 4.4.3 BIOLOGICAL MONITORING 194
4.4.3.1 DEMOGRAPHICS 194 4.4.3.2 MERCURY LEVELS IN URINE 196
4.4.3.2.1 RELATIONSHIP OF MERCURY EXPOSURE TO OTHER VARIABLES 198
4.5 DISCUSSION 198 4.5.1 DEMOGRAPHICS 199
4.5.1.1 VOLUNTEERS VS. PARTICIPANTS 199 4.5.1.2 CONTROL GROUP VS. EXPERIMENTAL GROUP 199
4.5.2 MERCURY MANAGEMENT IN THE WORKPLACE 200 4.5.3 MERCURY EXPOSURE 202
4.5.3.1 SUMMARY 205 4.5.4 OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT 205
4.5.4.1 TRAINING 206 4.5.4.2 LOCAL OCCUPATIONAL HEALTH AND SAFETY
MANAGEMENT ARRANGEMENTS 207 4.5.4.2.1 SUMMARY 211
4.5.4.3 ACCIDENTS AND ACCIDENT PREVENTION 211 4.6 SUMMARY 213
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CHAPTER 5 LEAD EXPOSURE MANAGEMENT IN QUEENSLAND 215 5.1 BACKGROUND 215
5.1.1 LEGISLATIVE CONTROLS 216 5.2 METHODS 217
5.2.1 RECRUITMENT OF PARTICIPANTS 217 5.2.2 QUESTIONNAIRE SURVEY OF LEAD DESIGNATED DOCTORS
IN QUEENSLAND 218 5.2.2.1 OCCUPATIONAL HEALTH SERVICE PERFORMANCE
CRITERIA 218 5.2.2.2 QUESTIONNAIRE DESIGN AND DISTRIBUTION 220 5.2.2.3 OTHER DATA SOURCES 222
5.3 ANALYSIS 222 5.4 RESULTS 223
5.4.1 RESPONSE RATE 223 5.4.2 GENERAL 224
5.4.2.1 QUALIFICATIONS 224 5.4.2.2 TIME AND ROLE AS A LEAD DESIGNATED DOCTOR 224 5.4.2.3 COVERAGE 225 5.4.2.4 RECENT ACTIVITIES 226 5.4.2.5 GENERAL ACTIVITIES 227 5.4.2.6 OTHER 230
5.4.3 COMPARATIVE ANALYSIS 232 5.4.3.1 QUALIFICATIONS OF DESIGNATED DOCTORS 232 5.4.3.2 OTHER 236
5.5 DISCUSSION 237 5.5.1 APPOINTMENT PROCESS 237 5.5.2 MAINTENANCE OF DESIGNATED DOCTORS’
DATABASE 238 5.5.3 QUALIFICATIONS 239 5.5.4 REGULATORY COMPLIANCE 241
5.5.4.1 RATE OF SURVEILLANCE 241 5.5.5 IMPROVEMENTS 243
5.6 SUMMARY 243 CHAPTER 6 OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS IN AUSTRALIA AND KOREA 245 6.1 BACKGROUND 245 6.2 INTRODUCTION 247 6.3 METHODS 248
6.3.1 DEVELOPMENT OF THE SELF-ASSESSMENT OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEM QUESTIONNAIRE 248
6.3.2 SELECTION OF CASES 251 6.4 ANALYSIS 252 6.5 RESULTS 255
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6.5.1 DEMOGRAPHICS (ALL RESPONDENTS) 255 6.5.1.1 DEMOGRAPHICS (AUSTRALIA) 256 6.5.1.2 DEMOGRAPHICS (KOREA) 257
6.5.2 ORGANISING 257 6.5.2.1 POLICY (ALL RESPONDENTS) 257 6.5.2.2 POLICY (AUSTRALIA) 258 6.5.2.3 POLICY (KOREA) 259 6.5.2.4 RESPONSIBILITY AND ACCOUNTABILITY (ALL
RESPONDENTS) 260 6.5.2.5 RESPONSIBILITY AND ACCOUNTABILITY
(AUSTRALIA) 262 6.5.2.6 RESOPNSIBILITY AND ACCOUNTABILITY (KOREA) 263 6.5.2.7 COMPETENCE AND TRAINING (ALL RESPONDENTS) 264 6.5.2.8 COMPETENCE AND TRAINING (AUSTRALIA) 265 6.5.2.9 COMPETENCE AND TRAINING (KOREA) 267 6.5.2.10 SYSTEM DOCUMENTATION AND COMMUNICATION
(ALL RESPONDENTS) 268 6.5.2.11 SYSTEM DOCUMENTATION AND COMMUNICATION
(AUSTRALIA) 269 6.5.2.12 SYSTEM DOCUMENTATION AND COMMUNICATION
(KOREA) 270 6.5.3 PLANNING AND IMPLEMENTATION 271
6.5.3.1 SYSTEM PLANNING AND OBJECTIVES (ALL RESPONDENTS) 271
6.5.3.2 SYSTEM PLANNING AND OBJECTIVES (AUSTRALIA) 272 6.5.3.3 SYSTEM PLANNING AND OBJECTIVES (KOREA) 274 6.5.3.4 HAZARD PREVENTION (ALL RESPONDENTS) 274 6.5.3.5 HAZARD PREVENTION (AUSTRALIA) 275 6.5.3.6 HAZARD PREVENTION (KOREA) 277
6.5.4 EMERGENCY PLANNING AND MANAGEMENT (ALL RESPONDENTS) 278 6.5.4.1 EMERGENCY PLANNING AND MANAGEMENT
(AUSTRALIA) 279 6.5.4.2 EMERGENCY PLANNING AND MANAGEMENT
(KOREA) 280 6.5.4.3 PROCUREMENT AND CONTRACTING (ALL
RESPONDENTS) 281 6.5.4.4 PROCUREMENT AND CONTRACTING (AUSTRALIA) 281 6.5.4.5 PROCUREMENT AND CONTRACTING (KOREA) 282
6.5.5 EVALUATION 283 6.5.5.1 PERFORMANCE MONITORING AND MEASUREMENT
(ALL RESPONDENTS) 283 6.5.5.2 PERFORMANCE MONITORING AND MEASUREMENT
(AUSTRALIA) 284 6.5.5.3 PERFORMANCE MONITORING AND MEASUREMENT
(KOREA) 286 6.5.5.4 OTHER ACTIVE AND REACITVE MEASURES (ALL
RESPONDENTS) 287
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6.5.5.5 OTHER ACTIVE AND REACTIVE MEASURES (AUSTRALIA AND KOREA) 288
6.5.5.6 INVESTIGATION OF ACCIDENTS (ALL RESPONDENTS) 289
6.5.5.7 INVESTIGATION OF ACCIDENTS (AUSTRALIA) 290 6.5.5.8 INVESTIGATION OF ACCIDENTS (KOREA) 291 6.5.5.9 AUDIT (ALL RESPONDENTS) 291 6.5.5.10 AUDIT (AUSTRALIA) 292 6.5.5.11 AUDIT (KOREA) 293 6.5.5.12 MANAGEMENT REVIEW (ALL RESPONDENTS) 294
6.5.6 ORAL HEALTH SERVICE 295 6.6 DISCUSSION 297
6.6.1 OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEM 297 6.6.1.1 RESPONSIBILITY AND ACCOUNTABILITY 298 6.6.1.2 OCCUPATIONAL HEALTH AND SAFETY POLICY 300 6.6.1.3 COMPETENCE AND TRAINING 302 6.6.1.4 EMERGENCY PREVENTION, PREPAREDNESS AND
RESPONSE 302 6.6.1.5 PROCUREMENT AND CONTRACTING 303 6.6.1.6 EVALUATION 304 6.6.1.7 HAZARD PREVENTION AND CONTROL ACTIVITIES 305
6.6.2 ORAL HEALTH SERVICE 307 6.7 SUMMARY 307 CHAPTER 7 GENERAL DISCUSSION 309 7.1 OBJECTIVES OF THE STUDY 309 7.2 LIMITATIONS OF THE STUDY 310
7.2.1 GENERAL 310 7.2.2 KOREAN EPIDEMIOLOGICAL DATA 310 7.2.3 ORAL HEALTH SERVICE STUDY 310 7.2.4 LEAD RISK MANAGEMENT IN QUEENSLAND 311 7.2.5 OCCUPATOINAL HEALTH AND SAFETY MANAGEMENT
SYSTEMS 311 7.3 THE EFFECTIVENESS OF HEAVY METAL EXPOSURE MANAGEMENT 312
7.3.1 MERCURY IN FLUORESCENT LAMP MANUFACTURING COMPANIES IN KOREA 312
7.3.2 MERCURY IN AN ORAL HEALTH SERVICE IN QUEENSLAND, AUSTRALIA 313
7.3.3 LEAD IN LEAD-RISK WORKPLACES IN QUEENSLAND, AUSTRALIA 314
7.4 THE MANAGEMENT OF LEGISLATIVE ARRANGEMENTS FOR HEALTH SURVEILLANCE IN KOREA AND QUEENSLAND, AUSTRALIA 315 7.4.1 FLUORESCENT LAMP MANUFACTURING COMPANIES IN
KOREA 315
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7.4.2 HEALTH SURVEILLANCE IN THE ORAL HEALTH SERVICE IN QUEENSLAND, AUSTRALIA 316
7.4.3 HEALTH SURVEILLANCE IN LEAD-RISK WORKPLACES IN QUEENSLAND, AUSTRALIA 316
7.5 THE CHARACTERISTICS OF THE OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS THAT ARE IN USE IN THE HEAVY METAL INDUSTRIES IN KOREA AND AUSTRALIA 318
7.6 THE EFFECTIVENESS OF OCCUPATIONAL HEALTH AND SAFETY MANAGEMENT SYSTEMS IN ENSURING A SAFE AND HEALTHY WORKPLACE 321
CHAPTER 8 CONCLUSION 315 REFERENCES 329 APPENDIX 3.1 – COMPARISON OF OUTLIERS A.1 APPENDIX 4.1 – STAFF INFORMATION PACKAGE A.3 APPENDIX 4.2 – AIR MONITORING SURVEY AT ORAL HEALTH SERVICE –
NOVEMBER 2001 A.7 APPENDIX 4.3 – ORAL HEALTH SERVICE QUESTIONNAIRE A.13 APPENDIX 4.4 – ORAL HEALTH SERVICE QUESTIONNAIRE DATA A.21 APPENDIX 4.5 – URINE MONITORING RESULTS A.29 APPENDIX 5.1 – LEAD MANAGEMENT QUESTIONNAIRE A.31 APPENDIX 5.2 – LEAD FOLLOW UP QUESTIONNAIRE A.35 APPENDIX 5.3 – LEAD MANAGEMENT DATA SET A.37 APPENDIX 6.1 – ENGLISH AND KOREAN VERSIONS OF SURVEY
QUESTIONNAIRE A.39 APPENDIX 6.2 – OHSMS DATA SET A.51 NOTE: BLOCK QUOTATIONS IN THIS THESIS ARE SHOWN IN BLOCK, SHADED
AND AT A SMALLER FONT THAN OTHER TEXT.
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List of Figures
Figure 2.1: Effects of inorganic lead on children and adults (lowest observable adverse-effect levels) (After:ATSDR 1992) 48
Figure 2.2: OHS Management system model (After:Standards Australia/Standards New Zealand 2001:vi) 90
Figure 3.1: Histogram of mercury levels in urine 110
Figure 3.2: Histogram of mercury levels in blood 110
Figure 3.3: Histogram of square root transformed data for mercury levels in urine 111
Figure 3.4: Histogram of square root transformed data of mercury levels in blood 112
Figure 3.5: Per cent of samples above and below Baseline Levels 115
Figure 3.6: Boxplaots of Median Levels of Mercury in Urine by Year 116
Figure 3.7: Blood samples analysed by year (Expressed as a percentage of urine samples analysed in the same year) 118
Figure 3.8: Boxplote of Hg levels in urine by gender (1994-1999) 119
Figure 3. 9: Comparison of Hg in urine by gender (1994-1999) 120
Figure 3.10: Median levels of Hg in urine by Workplace (1994-1999) 121
Figure 3.11: Comparison of Hg levels in urine by workplace (1994-1999) 122
Figure 3.12: Annual cases of Diagnostic Levels by workplace 123
Figure 3.13: Plot of Median Hg levels in urine by workplace and year 126
Figure 3.14: Plot of Median Hg levels in blood by workplace and year 127
Figure 3.15: Biological monitoring process and results 129
Figure 3.16: Median levels of mercury at first and second test for those exceeding Baseline Level at first test (1994-1999) 130
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Figure 3.17: Median levels of mercury in first and second blood tests (1994-1999) 131
Figure 3.18: Median concentrations of Hg in urine for cases in the Diagnostic Level range (1994-1999) 132
Figure 3.19: Median concentrations of Hg in blood for cases in the Diagnostic Level range (1994-1999) 133
Figure 3.20: Comparison of cases at Diagnostic Level by year 134
Figure 3.21: Comparison of first and second urine analyses for cases with mercury poisoning 135
Figure 3.22: Comparison of first and second blood analyses for cases with mercury poisoning 136
Figure 3.23: Number of first round urine samples analysed by year 137
Figure 3.24: Urine tests per workplace per year 137
Figure 3.25: Urine and/or blood samples in excess of Baseline Level by year 138
Figure 4.1: Recruitment process for study participants 155
Figure 4.2: Knowledge of mercury exposure across groups 169
Figure 4.3: Amalgam and health across groups 170
Figure 4.4: Receipt of information across occupation groups 172
Figure 4.5: Receipt of information across gender groups 173
Figure 4.6: Relationship between position description and control of mercury exposure 174
Figure 4.7: Relationship between feedback system and control of mercury exposure 174
Figure 4.8: Subjects receiving OHS training by workplace 176
Figure 4.9: Subjects reporting workplace health and safety committees in their facility 178
Figure 4.10: Awareness of occupational health and safety committee by occupation group 179
Figure 4.11: Formal feedback mechanisms identified by cases 180
Figure 4.12: OHS coordination responsibility allocated across workplaces 180
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Figure 4.13: Relationship between ability to attend safety related meetings and ability to improve OHS performance 182
Figure 4.14: Opportunity to improve health and safety performance by gender 183
Figure 4.15: Relationship between knowledge of risk assessor’s identity and information available on occupational health and safety 185
Figure 4.16: Relationship between availability of information and opportunity to improve health and safety 186
Figure 4.17: Sufficiency of health and safety information available by age group 187
Figure 4.18: Five highest ranked symptoms 188
Figure 4.19: Perceived major causes of accidents 189
Figure 4.20: Activities needed to improve health and safety performance 191
Figure 5.1: Role of designated doctors 225
Figure 5.2: Number of workplace for which designated doctors have responsibility 226
Figure 5.3: Frequency at which designated doctors visit workplaces 227
Figure 5.4: Activities observed at workplaces by designated doctors 228
Figure 5.5: Provision of information to employers and workers 229
Figure 5.6: Information provided to employers and workers by designated doctors 229
Figure 5.7: Activities to maintain/improve knowledge 230
Figure 5. 8: Respondents views of current system 231
Figure 5.9: Health surveillance in past year by qualifications 233
Figure 5.10: Attendance at conferences by qualification 234
Figure 5.11: Number of methods used to maintain/improve knowledge by qualification 235
Figure 5.12: Supervision of others by qualification 236
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Figure 6.1: Employment characteristics by type of company (Australia) 256
Figure 6.2: Employment rate by company (Korea) 257
Figure 6.3: Occupational health and safety policy elements (All respondents) 258
Figure 6.4: Occupational health and safety policy by size of workforce (Australia) 259
Figure 6.5: System of responsibility & accountability by degree of implementation (All respondents) 261
Figure 6.6: Progress towards implementation of a system of responsibility & accountability (All respondents) 262
Figure 6.7: Progress towards implementation of a system of responsibility & accountability (Korea) 264
Figure 6.8: Progress towards implementation of a training program (All respondents) 265
Figure 6.9: Training review by size of organisation (Australia) 266
Figure 6.10: Maintenance of signed training record by size of organisation (Australia) 267
Figure 6.11: Progress towards implementation of record and communication system (All respondents) 268
Figure 6.12: Implementation of injury record system by size of organisation (Australia) 269
Figure 6.13: Progress towards the development of a formalised OHSMS (All respondents) 271
Figure 6.14: Elements of OHSMS fully implemented across all organisations (All respondents) 272
Figure 6.15: Implementation of OHSMS by size of organisation (Australia) 273
Figure 6.16: Rate of use of different hazard identification methods (All respondents) 275
Figure 6.17: Use of hazard reporting system by size of workplace (Australia) 277
Figure 6.18: Progress towards implementation of emergency management system (All respondents) 278
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Figure 6.19: Documentation and maintenance of emergency management system by size of organisation (Australia) 280
Figure 6.20: Use of proactive and reactive measures to evaluate performance (All respondents) 284
Figure 6.21: Monitoring methods used to identify workers' exposure to hazardous substances (All respondents) 287
Figure 6.22: Frequency of blood tests (All respondents) 288
Figure 6.23: Frequency of audits (All respondents) 292
Figure 6.24: Frequency of management review of OHSMS (All respondents) 294
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List of Tables
Table 2.1: Statistics of industrial accident and occupational data in the World 17
Table 2.2: The average half-life for clearance of mercury in the body (After:Sherlock 1984) 23
Table 2.3: Studies of occupational exposure to mercury:An analysis of the scientific literature 31
Table 2.4: Studies of amalgam exposure to dental staff 35
Table 2.5: General signs and symptoms of lead toxicity 47
Table 2.6: Summary of health surveillance standards and regulations for lead in U.S.A. 51
Table 2.7: Reference level of lead exposure in blood in Korea 51
Table 2.8: Common sources of lead exposure 53
Table 2.9: Description of state of OHS development in Australia and Korea 76
Table 2.10: Essential elements of an occupational health and safety management system 83
Table 2.11: Examples of occupational health and safety management systems 92
Table 3.1: Korean biological exposure indices for mercury 107
Table 3.2: Beneral demographic characteristics of workplaces (1994-1999) 114
Table 3.3: Results of Hg levels in urine and blood by year 116
Table 3.4: Mean ranks of mercury in blood analysis (1997-1999) 118
Table 3.5: Median level of Hg in urine by Workplace (1994-1999) 120
Table 3.6: Cases of Diagnostic Levels by workplace and year 122
Table 3.7: Median Hg in Urine in Companies by Year 124
Table 3.8: Follow-up biological monitoring tests by year 139
Table 4.1: Biological exposure indices for mercury 153
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Table 4.2: Workplaces of volunteers and participants in questionnaire survey 164
Table 4.3: Gender of volunteers and participants in questionnaire survey 164
Table 4.4: Demographics of cases completing questionnaire 166
Table 4.5: Occupation groups of survey participants by gender 168
Table 4.6: Awareness of mercury absorption by occupation group 171
Table 4.7: Wearing of personal protective equipment by occupation 171
Table 4.8: Receipt of information on the safe use of amalgam at work across occupation groups 172
Table 4.9: Workplace health and safety training 176
Table 4.10: Participation in health and safety related activities 182
Table 4.11: Cases who identify particular perceived causes of accidents 190
Table 4.12: Cases who identify particular activities to improve OHS performance 192
Table 4.13: Air monitoring summary of results 193
Table 4.14: Demographics of cases providing urine samples 195
Table 4.15: Dental staff with detectable mercury levels in urine test 197
Table 5.1: Summary of quality measures that are often cited as most relevant to OHS. 219
Table 6.1: OHSMS components scale used for data collection and analysis 253
Table 6.2: Second OHSMS components scale used for data collection and analysis 254
Table 6.3: Scale for OHSMS elements in place for data collection and analysis 254
Table 6.4: Australia - Policy 259
Table 6.5: Korea - Policy 260
Table 6.6: Australia - Responsibility and accountability 263
Table 6.7: Korea – Responsibility and accountability 263
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Table 6.8: Australia - Competence and training 265
Table 6.9: Korea - Competence and training 267
Table 6.10: Australia - System documentation and communication 269
Table 6.11: Korea - System documentation and communication 270
Table 6.12: Australia - Planning and implementation 273
Table 6.13: Korea - Planning and implementation 274
Table 6.14: Australia - Hazard prevention 276
Table 6.15: Korea - Hazard prevention 278
Table 6.16: Australia - Emergency prevention management 279
Table 6.17: Korea - Emergency prevention management 280
Table 6.18: Australia - Procurement and contracting 281
Table 6.19: Korea - Procurement and contracting 283
Table 6.20: Australia – Performance monitoring and measurement 285
Table 6.21: Korea – Performance monitoring and measurement 286
Table 6.22: Australia - Health surveillance and air monitoring 288
Table 6.23: Australia - Investigation of accidents 290
Table 6.24: Korea - Investigation of accidents 291
Table 6.25: Australia - Audit program 293
Table 6.26: Korea - Audit program 294
Table 6.27: Summary of Oral Health Service responses 296
Table 6.28: Australia vs. Korea - Implementation of OHS management system 298
Table 6.29: Australia vs. Korea - Responsibility and accountability 299
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-XXIII-
The work contained in this thesis has not been previously submitted for a degree or diploma at any other higher education institution. To the best of my knowledge and belief, the thesis contains no material previously published or written by another person except where due reference is made.
Signed:
Date:
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-XXV-
Acknowledgements
This thesis is the result of four and half years of work during which I
have been accompanied and supported by many people. It is a
pleasant aspect that I now have the opportunity to express my
gratitude to all of them.
My acknowledgment would not be complete without expressing due
regards and gratitude to all the participants in my study for their
cooperation and patience without which this study would not have been
possible.
I would like to thank Rob Seljak then General Manager in the Division
of Workplace Health and Safety, Queensland for giving me permission
to conduct the lead study in Queensland, and to Penny Digby (Snr
inspector) who gave me expert guidance and allowed me to use
Departmental data. Furthermore I would like to thank Dr. David
McMaugh and Dr. Ralph Neller who helped me set out the study cohort
for the dental study and the Queensland Dental Association for funding
my analysis of mercury in urine samples from the oral health service.
During my study I received a lot of valuable comments from the
following people; Geoff Hitchings, Adrian Savage, Gary Chaplin, Dr.
John Cameron and Dr. Keith Adam. I thank them for their professional
advice on my project.
I would like to make special mention of Dr Choi, Department of
Preventive Medicine in Korea University for his kind support in
providing the epidemiological data for the Korean component of this
study. My brain was stimulated at my first meeting with him in 1992.
Since then I haven’t stopped challenging myself. This has lead to
some stressful but mostly exciting experiences. I want thank him for
the positive attitude he has shown to my work.
-XXVI-
To my profound thanks go to professor Mike Capra who really does
deserve the greatest of thanks, since he has provided me with
incredible support, encouragement and trust without harassing me. I
have known him since 1999 when I commenced my PhD, during these
years I have known him as an enthusiastic, scholarly and very nice
person. His efforts to remain in close contact with me following his
transfer are particularly appreciated. It was great pleasure to me to
conduct this thesis under his supervision and I am glad that I have had
the opportunity to get to know him and work with him as his “academic
child”.
My thanks also go to Terry Farr. This thesis was enriched significantly
through helpful discussion with him and his valuable advice and
professional expertise. There were points where we did not agree, but I
enjoyed the discussions; he taught me logic and challenged me in
many ways. His support for me extended well beyond the huge role he
played as an associate supervisor. I am immensely grateful to him for
the time he made available for me. Also I wish express my gratitude to
him to editing and reviewing the manuscript of this thesis.
Needless to say, I am grateful to my colleagues at the School of Public
Health for their support and tolerance; especially I am indebted to Kelly
Johnstone for having shared the same cosy-corner laboratory room
with me and for being a good friend and sister for the last 4 years.
The most important persons to whom I would like to express my deep
appreciation are my father, for his understanding and support of my
goals throughout my life, and my mother, for her encouragement,
patience, pride and unconditional love. I do not believe that I could
have successfully completed my studies in a “strange” country and in a
foreign language without your ongoing support and concern for my
wellbeing. I love you so much from bottom of my heart.
-1-
Introduction
1.1 Background
1.1.1 Legislative framework for occupational health and safety in Australia and Korea
The 1970’s was a period of great social, political and economic
upheaval in Australia. The period marked the end of the post World
War II economic boom, and was a period of great social unrest. It was
a period which saw the introduction of universal health insurance, the
growth of the women’s movement, the green movement, and the anti-
Vietnam war movement. It was also a period of major restructuring of
the manufacturing industry and the economy in general. All of these
factors influenced the rank and file workers’ health movement which
emerged in the mid 1970’s and began to argue for reform to the old
prescriptive style occupational health and safety legislation in place
around the country (Biggins, 1987; Carson, 1989; Pearse, 1984).
This rank and file workers’ health movement found an unusual ally in
big business which, shaken by major chemical disasters around the
world, realised that the “old” approach to occupational health and
safety was no longer relevant in industries which were becoming more
specialised and increasing dramatically in size. These events in
Australia mirrored similar situations in countries such as the United
Kingdom.
As a result of these influences, all Australian states undertook a major
rewriting of their occupational health and safety laws in the 1980s and
moved from prescriptive style legislation to performance based
1
Introduction
-2-
legislation modelled on changes which took place in the United
Kingdom in the 1970s following the report into occupational health and
safety by a committee chaired by Lord Robens (Committee on Safety
and Health at Work & Robens, 1972). This new legislation set
standards of health and safety performance that needed to be met by
industry but moved the decision-making on how these standards were
to be achieved back to the workplace. It was not a process of self-
regulation, as often reported, but rather, a process whereby the state
changed its role. Rather than take responsibility for how industry would
achieve a safe working environment by stipulating how controls would
be implemented in the workplace, the state now required that industry
decide and be able to demonstrate how it was achieving the standard
of health and safety in the workplace required by the state (Biggins,
1987).
Influenced by the strength of the workers’ health movement, this
legislation also enshrined the role of workers in achieving a safe and
healthy working environment. Participation by workers in decisions
affecting health and safety permeates the legislation as does their right
to be informed and educated on the hazards that they face in the
workplace. Similarly, influenced by the demands of big business and
its concerns about the adverse effects of major disasters, the legislation
emphasises the need for organisations to be able to demonstrate that it
has systems in place to identify hazards and manage risks. Further, in
the event that something does go wrong, an emphasis is also placed
on emergency planning. However, to provide flexibility to industry on
how their particular problems are to be solved, the legislation, by and
large, does not stipulate how risks are to be managed, but establishes
obligations for those who interact in the workplace and standards of
performance to be achieved.
Likewise, the Korean labor market went through dramatic changes in
the latter half of the 1970s. By the late 1970s Korea was transformed
from an agricultural economy to an industrial economy. The labor
Introduction
-3-
market moved from one of excess supply of labor to one of balanced
supply. In this environment workers strived to improve their basic rights
and income.
By the late 1980s, with political democratisation in 1987, workers
became even more aware of their rights and large scale labor disputes
spread across the nation. In the early 1990s both workers and
management were calling for changes to the labor laws in Korea.
Workers were arguing for an extension of their basic rights and
management for greater employment flexibility.
During this turmoil, there were also changes to the occupational health
and safety laws in Korea. However, “compared to attention paid to
industrial relations or economic growth, the field of Industrial Safety and
Health was given relatively little attention (Department of Labor: Korea,
c 1999: 27)”. Perhaps as a requirement for an emerging industrial
economy, the Korean legislation is prescriptive in nature and stipulates
measures to enhance working conditions. This is in stark contrast to
the situation in Australia.
In response to:
the number of serious industrial accidents [that] rapidly increased due to mechanical equipment’s growing size and speed and construction projects’ growing scale, and the number of occupational diseases [that] increased due to the massive use of hazardous chemical materials the independent industrial Safety and Health Act was enacted and promulgated on 31 December 1981 (Department of Labor: Korea, c 1999: 27).
The difference in approach between the Australian and Korean
legislation is evidenced in the following quote regarding the changes
that took place in the legislation in 1990:
After the enactment of the Industrial Safety and Health Act in 1981, the standards on industrial safety and health were totally revised for the first time on 13 January 1990, stipulating the Government’s responsibilities regarding industrial safety and health, solving problems that existed in the Workplace Safety and Health System (Department of Labor: Korea, c 1999: 27).
Introduction
-4-
The difference here lies in the stipulation of government
responsibilities. In Australia, the changes to legislation in the 1980s
moved the responsibility for ensuring a safe and healthy workplace
from government to the workplace. In Korea the government still
accepts much of the responsibility of achieving safe and healthy
workplaces by stipulating the ways in which industry must operate with
respect to occupational health and safety.
However, there are indications that the Korean system is undergoing
change. One of the tasks of its 1999 Three-Year Plan for the
Advancement of Safety and Health is to “join the ranks of industrialized
countries in terms of industrial safety & health system(s) (Department
of Labor: Korea, c 1999:29)”.
1.1.2 The growth of occupational health and safety management systems
This latter point directs attention to one of the phenomena that appears
to have arisen in response to the performance-based legislative
approach to occupational health and safety in Australia and other
countries. That is, the growth of occupational health and safety
management systems as a way of improving and maintaining health
and safety performance in the workplace.
An occupational health and safety management system is:
That part of the overall management system which includes organizational structure, planning activities, responsibilities, practices, procedures, processes and resources for developing, implementing, achieving, reviewing and maintaining the OHS policy, and so managing the risks associated with the business of the organization (Standards Australia/Standards New Zealand, 2001: 4).
While the emergence of occupational health and safety management
systems has been noted in countries with performance-based
legislation (Quinlan, 1999) no research has been done to determine
whether or not the legislative approach taken by government influences
the introduction or form of occupational management systems used by
Introduction
-5-
organisations. Similarly, although the reasons why Australia and other
countries have moved to performance-based legislation have been
explained in terms of the social, political and economic factors that
influenced the change, little research has been done on the
effectiveness of this approach compared with the prescriptive approach
of countries like Korea.
1.2 Aims and objectives
The overall aim of this study is to develop a comprehensive
understanding of the management of exposure to heavy metals1 in
selected industries in Korea and Australia. Determining the prevalence
of heavy metal poisoning will assist in evaluating the effectiveness of
occupational health and safety legislation in preventing work-related
illness and by implication work-related injuries.
The specific objectives of this study are to determine:
The effectiveness of heavy metal exposure management in the
fluorescent lamp manufacturing industry in Korea, and an Oral
Health Service, and lead-risk workplaces in Queensland,
Australia;
The management of the legislative arrangements for health
surveillance in Korea and Queensland, Australia;
The characteristics of the occupational health and safety
management systems that are in use in the heavy metal
industries in Korea in Australia; and
The effectiveness of prescriptive and performance based
legislative systems in protecting the health and safety of
workers in heavy metal based industries.
1 Heavy metals are defined in the CCH Occupational Health & Safety Glossary (1992:79) as “metals of high densities, and some of them, notably lead, mercury and cadmium, are toxic.
Introduction
-6-
1.3 Overview of the dissertation
Chapter 2 presents a literature review of the subject matter with
emphasis on: the toxicology of, and occupational exposures to,
mercury and lead; the legislative systems for occupational health and
safety in Korea and Australia, concentrating on the requirements for
exposure to hazardous substances; and the development and impact
of occupational health and safety management systems.
Chapter 3 presents the analysis of data outlining the exposure to
mercury of workers in the fluorescent lamp manufacturing industry in
Korea. The extent of mercury poisoning over the period 1994 to 1999
is examined and overall trends and the contribution of individual
workplaces to the total are identified.
Chapter 4 presents the data collected on mercury exposure in dental
workers in Queensland. The relationship between a range of
occupational and environmental factors as reported in the literature that
could affect mercury exposure is examined.
Chapter 5 presents data collected on the management of the health
surveillance program by designated lead doctors in Queensland. Data
on the extent of blood lead testing and lead poisoning is presented.
The effectiveness of the system in providing the government with a
picture of lead exposure in the workplace is discussed as are possible
improvements to the system.
Chapter 6 presents data collected on the occupational health and
safety management systems in place in fluorescent lamp
manufacturing companies in Korea, and an Oral Health Service and
lead-risk workplaces in Queensland. Differences between the systems
in Korea and Australia are presented and factors such as size of
workplace and legislative framework that influence the nature of the
system introduced are analysed.
Introduction
-7-
Chapter 7 presents an overall discussion of the study focusing on the
outcomes of the study’s objectives.
Chapter 8 presents the concluding comments of this dissertation.
Recommendations are made for further study and the limitations of the
present study are explored.
1.4 Ethics approval
The Human Research of Ethics Committee at QUT approved the
overall project protocol and the protocol for the individual components
of the study. Additional ethical approval was obtained from other
bodies for particular sections of the study and this is noted in the
methodology of the appropriate chapter.
Introduction
-8-
-9-
Literature review
2.1 Introduction
Occupational safety and health hazards are sometimes, implicitly, pictured as something form the dark industrial past. As a phenomena from the age of the steam engine that has been adequately dealt with in the post-post-industrial age by means of technological, organizational and regulatory innovations and efforts (Frick, Per Langaa et al., 2002)
The knowledge of the work environment has increased in a number of
areas, but the degree of control of work environment has not increased
proportionally (Frick, Per Langaa et al., 2002).
Serious chemical or energy industry related disasters and incidents
over the last 15-20 years, such as the Flixborough disaster2 in the UK
in 1974, Bhopal3 in 1984, Chernobyl4 in 1986 and the Alpha North Sea
2 At about 16:53 hours on Saturday 1 June 1974 the Nypro (UK) site at Flixborough was severely damaged by a large explosion. Twenty-eight workers were killed and a further 36 suffered injuries. It is recognised that the number of casualties would have been more if the incident had occurred on a weekday, as the main office block was not occupied. Offsite consequences resulted in fifty-three reported injuries. Property in the surrounding area was damaged to a varying degree Vassilakis, K. (n.d.). Afterthoughts on the 25th Anniversary of the Flixborough Disaster. [Web document]. Available: http://www.svce.ac.in/~bnedu/Subjects/SAFETY/safety,htm [23rd September 2003]. 3 The Bhopal Gas Tragedy is a catastrophe that has no parallel in industrial history. In the early morning hours of December 3, 1984 a rolling wind carried a poisonous grey cloud past the walk of the Union Carbide C plant in Bhopal, Madhya Pradesh , India. An estimated 8,000 or more people died (over three times the officially announced total), The cause was the contamination of Methyl Isocyanate (MIC) storage tank No. 610 with water carrying catalytic material. Responsible estimates suggest that as many as 10,000 may have died immediately. The precise number of deaths still remains a mystery. 2,000,00 were injured and 30,000 to 50,000 were too ill to ever return to their jobs. This is the Hiroshima of chemical industry (TED Case Studies: Bhopal Disaster n.d.)Ted Case Studies: Bhopal Disaster (n.d.). [Web document]. Available: http://www.american.edu/TED/bhopal.htm [23rd September 2003].}. 4 In April 1986, Chernobyl' (Chornobyl' in Ukrainian) was an obscure city on the Pripiat' River in north-central Ukraine. Almost incidentally, its name was attached to the V.I. Lenin Nuclear Power Plant located about twenty-five kilometres upstream. On April 26, the city's anonymity vanished forever when, during a test at 1:21 A.M., the No. 4 reactor exploded and released thirty to forty times the radioactivity of the atomic bombs dropped on Hiroshima and Nagasaki. The world first learned of history's worst nuclear accident from Sweden, where abnormal radiation levels were registered at one of its nuclear facilities.
2
Literature Review
-10-
Disaster5 in 1988 have increased Government and public expectations
that industries such as these will have stringent systems of safe guards
built into their management and production process (WorkCover,
1994). Similar requirements have gradually spread to other, less
hazardous industries and Australian occupational health and safety
legislation now requires that all organisations take a proactive risk
management approach to the management of risks associated with
their operations (National Occupational Health and Safety Commission,
2001). In Australia, further vigour in this approach was evident
following the explosion in the Esso gas plant at Longford6 in 1998
(Hopkins, 2000; Hopkins, 2002).
The system of safeguards built into their management and production processes is expected to be commensurate with the risk posed by the operation of the enterprise. The obvious goal is that strategies must bring about sustainable improvements in the injury and illness rates of organisations. However such measures can often only be judged over time. It is therefore difficult to assess short-term success, or indeed, the merits of the intervention strategy itself. The generic or universal use of specifically defined performance criteria may result in an inconsistent performance measurement, resulting from many factors including culture, systematic differences and legislative frameworks. Comparisons therefore, are often difficult (Quinlan, 1999).
In the year 1999/2000 in Australia, there were 139,039 non-fatal and
262 fatal work-related incidents that attracted workers’ compensation
(National Occupational Health and Safety Commission, 2004a). This
source is recognised as giving an underestimate of the actual
incidence of work-related injury and death (National Occupational
Health and Safety Commission, 2000).The Work-Related Fatality
Study, Australia, 1989-1992 is considered more reliable and placed the
work-related fatal injuries in 1992 at 450 (National Occupational Health
and Safety Commission, 2000). No information on work-related
disease is included in these figures.
5 Piper Alpha was an oil platform in the North Sea that caught fire and burned down on July 6, 1988. It was the worst ever-offshore petroleum accident, during which 167 people died and a billion dollar platform was almost totally destroyed. 6 On 25 September 1998 an explosion at the Esso gas plant at Longford, Victoria killed two men, injured eight others and cut Melbourne’s gas supply for two weeks.
Literature Review
-11-
These figures are enough to understand the importance of effective
preventive measures against occupational accidents and safeguarding
health in all work environments, regardless of company size or sector.
Accidents at the workplace entail significant costs for the community
and companies. This is one reason why various laws have been
passed in recent years for the safety and health of workers on the job.
Such an important problem must be faced adequately with
professionally trained personnel and a dynamic as well as methodical
and rigorous management system.
The purpose of this chapter is to provide an introduction to the literature
on the nature of workplace hazards and ways of minimising or
controlling those hazards.
The aims of this chapter are to;
Clarify the concept of occupational health and safety;
Outline workplace hazards (mercury and lead) and their control;
Introduce the legislative system in Korea and Australia;
Provide a framework for an understanding of occupational
health and safety management systems;
Stimulate an interest in the occupational health and safety
legislative system and a commitment to be involved in legal
regulation and occupational health and safety management
systems to prevent workers from workplace hazards.
This chapter is the first comprehensive attempt to describe and assess
distinctive features of occupational health and safety management
systems and heavy metal exposure in the workplaces, including its
regulatory context.
Literature Review
-12-
A simple structure divides the remainder of this Chapter into three
broad areas that might be expected to generate useful information to
understand this thesis:
Occupational exposure to heavy metals with special reference
to the toxicology of, and occupational exposure to, mercury and
lead;
Legislative systems in Korea and Australia; and
Occupational health and safety management systems.
2.2 Occupational exposure to heavy metals
2.2.1 Introduction
Metals constitute a major category of toxins that pose a significant
threat to health through occupational as well as environmental
exposure.
One indication of their importance relative to other potential hazards is
their ranking by the U.S. Agency for Toxic Substances and Disease
Registry, which lists all hazards present in toxic waste sites according
to their prevalence and the severity of their toxicity (Agency for Toxic
Substances and Disease Registry, 2003)7.
Lead and mercury are on the list as a first, second respectively, Arsenic
and Cadmium are third, and sixth hazards on the list respectively.
The atomic stability of metals allows their relatively easy tracing and
measurement in biological material, although the clinical significance of
7 By Congressional mandate, the Agency for Toxic Substances and Disease Registry (ATSDR) produces "toxicological profiles" for hazardous substances found at National Priorities List (NPL) sites. These hazardous substances are ranked based on frequency of occurrence at NPL sites, toxicity, and potential for human exposure. Toxicological profiles are developed from a priority list of 275 substances. So far, 269 toxicological profiles have been published or are under development as "finals" or "drafts for public comment" 244 profiles were published as finals; 106 profiles have been updated. Currently, 16 profiles are being revised based on public comments received and 1profile is being developed as public comment draft. These profiles cover more than 250 substances.
Literature Review
-13-
the levels measured in not always clear. Metals are inhaled primarily
as dusts and fumes (Agency for Toxic Substances and Disease
Registry, 2003).
Metal poisoning can also result from exposure to vapours (e.g.,
mercury vapour in the manufacture of fluorescent lamps, and dental
amalgam) (American Dental Association, 2000; Agency for Toxic
Substances and Disease Registry, 1990; Barregard, 1992).
When metals are ingested in contaminated food or drink or through
hand-to-mouth activity, their gastrointestinal absorption varies greatly
with the specific chemical form of the metal and the nutritional status of
the host (Berlin, 1986).
Once metal is absorbed, blood is the main medium for its transport,
with the precise kinetics dependent on diffusibility, binding forms, rates
of biotransformation, availability of intracellular ligands, and other
factors (Campbell, 1992; Chamberlian, 1985). Some organs (such as
bone, liver, and kidney) sequester metals in relatively high
concentrations for years (Lange, 2003).
To understand the issues involved in the health and safety of workers
who are exposed to heavy metal (especially, mercury and lead), we
need first to examine a range of issues and perspectives that provide a
context for occupational health and safety management system.
2.2.2 What is occupational health?
Before examining the relative merits of occupational health and safety
management systems, it is necessary to address the importance of
occupational health and safety, and the relationship between
occupational health and safety and occupational health and safety
management system.
Literature Review
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2.2.2.1 Definitions
There are relatively few definitions of occupational health and safety
within the literature and the majority of these tend to focus on the
aspects of health.
The discipline of occupational health is concerned with the:
two-way relationship of work and health:
Health Work
It is as much related to the effects of the working environment on the health of the worker, as it is to the influence of the works’ state of health on his/her ability to perform the tasks for which s/he was employed (Harrington, 1992:p 3).
Perhaps the best known definition of occupational health is that
adopted by the Joint ILO/WHO Committee on Occupational Health in
1950:
Occupational health should aim at the promotion and maintenance of the highest degree of physical, mental and social well-being of workers in all occupations; the prevention amongst workers of departures from health caused by their working conditions; the protection of workers in their employment from risks resulting from factors adverse to health; the placing and maintenance of the worker in an occupational environment adapted to his physiological and psychological capabilities and; to summarize: the adaptation of work to man and of each man to his job.
The main focus in occupational health is on three different objectives: (i) the maintenance and promotion of workers’ health and working capacity; (ii) the improvement of working environment and work to become conducive to safety and health and (iii) development of work organizations and working cultures in a direction which supports health and safety at work and in doing so also promotes a positive social climate and smooth operation and may enhance productivity of the undertakings. The concept of working culture is intended in this context to mean a reflection of the essential value systems adopted by the undertaking concerned. Such a culture is reflected in practice in the managerial systems, personnel policy, principles for participation, training policies and quality management of the undertaking (Stellman, 1998: 16.1-16.2).
The United States Department of Health and Human Service, Federal
Occupational Health defined occupational health as below;
Literature Review
-15-
Occupational health is the science of designing, implementing and evaluating comprehensive health and safety programs that maintain and enhance employee health, improve safety and increase productivity in the workplace (What is occupational health, c 2000).
2.2.3 The extent of occupational injury and disease
Currently there are some one-quarter of a million chemicals used in all
work places. Some 15,000 are in industrial use. Many have been
shown to be hazardous not only for cancer, but for a host of other
diseases – silicosis form silica dust, most notably among miners;
berylliosis from beryllium; severe skin disorders from solvents, deadly
toxicity from heavy metals; and so on. Only small proportions of these
chemicals have been adequately tested for human effects (Elling,
1986).
In the United States each year:
5,000,000 workers are injured on the job; 150,000 of whom suffer permanent work-related disabilities, including maiming, paralysis, impaired vision, damaged hearing, and sterility.
100,000 become seriously ill from work-related diseases, including black lung, brown lung, cancer, and tuberculosis.
14,000 are killed on the job; about 90 percent are men.
100,000 die prematurely from work-related diseases (Parenti, 1992).
Sweden is a much smaller industrialized country (some 8.3 million
versus the U.S.A.’s 230 million population), which has proceeded
further than the U.S.A. and most other countries in protecting workers
from occupational health and safety problems (Kelman, 1981). It is still
estimated that 300 workers die each year from work-related causes;
some 120,000 are hurt at or enroot to/from work in Sweden. These
figures do not include injuries resulting from stress, monotony or a
steadily increasing workplace (The Swedish Institute, 1979).
The most recent estimates of the overall level of work-related disease
in Australia are contained in the Kerr report (Kerr, 1996). Although the
Literature Review
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estimates are based on information of varying reliability and some of
the assumptions on which the estimates are based have been
questioned, if the true level of disease were even one-quarter of that
suggested by the Kerr estimates, disease would still be a bigger cause
of work-related death than injury. Kerr (1996) estimates the work-
related disease toll in Australia at:
Number of deaths each year: 2,290
Rate of deaths: 16.1 per 10,000 persons per year
In comparison, in Queensland for example, the Queensland Employee
Injury Database Summary Report shows that:
During the twelve months ended 30 June 2000, a total of 29,850 compensated workplace injuries meeting the criteria listed in the introduction were recorded.
The number of injuries per 100 employees during1999-2000 was 2.1 for all industries. Manufacturing industry workers had the highest proportion of injuries with 25.8 per cent (7,689) of all injuries. The injury rare was also highest for manufacturing industry workers (4.7 injuries per 100 employees).
Of the 29,850 injuries that occurred during 1999-2000, 9.9 per cent (2,946 injuries) were classified as severe. During 1999-2000, 679,124 workdays were lost in all industries due to work injuries. Total compensation of A$111,288,506 was paid in 1999-2000 for the 29,850 injuries (Division of Workplace Health and Safety, 2001).
One of the weaknesses of current occupational health and safety data
dissemination in Australia is that there is no central collection and that
data from a range of sources is generally not drawn together or the
results from the range analysed or at least considered together. Other
limitations of occupational health and safety data include the lack of
national datasets, comprehensive datasets, and comparability between
existing datasets (National Occupational Health and Safety
Commission, 2000). However, the information included does provide a
good indication of what occupational health and safety data currently
exist in Australia (National Occupational Health and Safety
Commission, 2000).
Literature Review
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On a global scale, the injury and fatality rates for a number of countries
are given in Table 2.1.
Table 2.1: Statistics of industrial accident and occupational data in the World
Nation Source of data Statistics Australia National Safety Council of
Australia Ltd No. of workers: 8,408,289 (1996) No. of injuries and illnesses: 389,000(1996) No. of fatalities: 503 (1994/95)
Brunei Darussalam Construction planning & research unit, Ministry of Development
No. of workers: 20,000 No. of injuries and illnesses: 120 No. of fatalities: 2
Hong Kong The Hong Kong Occupational Safety and Health Association
No. of employees at work: 3,433,000 No. of industrial accidents: 43.034 (1998) No. of occupational injuries: 63,526 (1998) No. of occupational fatal accidents: 240 (1998)
India National Safety Council (NSCI) (Industrial accident statistics for year 1993) No. of workplaces: Factories: 234,195 Mines: n/a Railways: n/a Major plantations: n/a Motor transport undertakings: 36,005 No. of workers: Factories: 8,928,000 Mines: 779,000 Railways: 1,054,000 Major plantations: 1,084,000 Shops and establishments: 4,122,000 Motor transport undertakings: 362,494 No. of injuries: Factories: 84,408 Ports: 571 Mines: 1,482 Railways: 11,042 Major plantations: n/a Shops and establishments: n/a Motor transport undertakings: n/a No. of fatalities: Factories: 874 Ports: 21 Mines: 249 Railways: 419 Major plantations: n/a Shops and establishment: n/a Motor transport undertakings: n/a
Japan Industrial Safety and Health Association
No. of injuries and illnesses: FY 1997; 156,726 No. of fatalities: FY 1998; 1,844
Korea Occupational Safety and Health Agency
(Industrial accident statistics for 1999) No. of workplaces: 249,405 No. of workers: 7,441,160 No. of injuries and illness: 55,405 No. of fatalities: 2,291 Fatality rate per 10,000: 3.08 Accident rate: 0.74
Malaysia National Institute of Occupational Safety and Health (NIOSH)
(Industrial accident statistics for 1997) No. of workplaces/employers: 338,794 No. of workers: 8,252,680 No. of injuries and illness: 86,589 No. of fatalities: 1,307
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Nation Source of data Statistics Mongolia Mongolian Labour Protection
Movement No. of workers: 842.9(1997), 859.3(1998) No. of injuries and illness: 632 (1997), 880 (1998) No. of fatalities: 48 (1997), 46(1998) No. of persons who be came disabled: 72 (1997), 42 (1998)
Pakistan Central Inspectorate of Mines (Industrial accident statistics for 1997) No. of registered factories where 10 or more persons work: 9,674 No. of workers in registered factories: 1,831,745 No. of mines and oilfields: 2,892 No. of workers in mines & oilfields: 184,391 No. of injuries and illness: 1,759 No. of fatalities Factories: 105 Mines: 142
Singapore National Safety Council of Singapore (NSCS)
(Industrial accident statistics for 1998) No. of workplaces: 15,928 No. of workers: 686,358 No. of injuries and illness: 4,247 No. of fatalities: 103 (1997)
Thailand The National safety Council of Thailand (NSCT)
(Industrial accident statistics for recent year: year is not available) No. of workplaces: 90,656 No. of workers: 6,084,822 No. of injuries and illness: 229,343 No. of fatalities: 1,033
Taiwan Chinese Taipei Industrial Safety and Health Association
(Industrial accident statistics for 1997) No. of workplaces: 121,439 No. of workers: 6.5 millions No. of injuries and illness: 27,218 No. of fatalities: fatality rate/1000: 0.091
Vietnam National Institute of Labour Protection (NILP)
(Industrial accident statistics for recent year: year is not available) No. of workplaces (as in public sector): 41,517 No. of workers (as in public sector): 3,214,000 No. of injuries and illness (as in public sector): 1,063 No. of fatalities (as in public sector): 415
Sweden
National Board of Occupational Safety and Health
Time period: 1979-to date Over the last 5 years an average of 90000 accidents, 50000 disease and 15000 commuting accidents have been reported
Spain Directorate General for Information Technology and Statistics
692,633 accidents were reported at work in 1989
Portugal National Insurance Fund for Occupational Disease
15,567 occupational diseases were registered in 1989 Pneumoconiosis: 10500 Deafness: 3289 Dermatosis: 810 Other: 968
Norway National Institute of Public Health (NIR) : (The National Injury Register)
The NIR collects data on approximately 5000 occupational injuries per year. Data on approximately 130,000 cases registered from 1990-1992 and describing all types of injuries
The Association of Norwegian Insurance companies (Database over occupational injuries& occupational disease)
Approximately 2,000 occupational accidents or occupational disease have been reported to the system every year since 1990
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Nation Source of data Statistics Finland Federation of Accident
Insurance Institutions Time period: 1975-to date The system contains data of all accidents at work or occupational disease in Finland that have been compensated on basis of statutory workmen’s compensation system (total number of cases in roughly 150,000/year)
Denmark Danish Working Environment Services, (the Registry of Occupational Injuries)
Time period: 1983- to date Around 50,000 accidents have been reported to the registry yearly during the recent years
National Working Environment Service (the Registry of occupational disease)
Time period: 1983- to date Around 18,000 occupational disease are reported to the register every year, of which 15,000 are new cases
ILO International Labour Office Every year, 250 million accidents, 160 million occupational diseases occur, the equivalent of 685,000 accidents every day, 4785 every minute, 8 every second. Working children suffer 12 million occupational accidents and an estimated 12,000 of them are fatal. 3,000 people are killed by work every day, 2 every minute Dr Takala, chief of the International Labour Office’s Health and Safety pointed out that the workplace hecatomb of 1.1 million deaths exceeds the average annual deaths from road accident (999,000), war (502,000), violence (563,000) and HIV/AIDS (312,000). Approximately one –quarter of those deaths results from exposure to hazardous substances He warned that work-related disease are expected to double by year 2020 and that if improvements are not implanted now, exposure today will kill people by the year 2020. Also according International Labour Office, some 600,000 lives would be saved every year if available safety practice and appropriate information were used.
Reference (International Labour Office, 1999; Asia Pacific Occupational Safety and Health Organisation, 2003; HASTE, 2003)
When discussing workplace injury and disease care should be taken in
the use of terms which sometimes give a false impression of their
inevitability. The term “accident” is used throughout this thesis as a
term to describe events leading to occupational injury or, on occasions,
disease. The use of this term is not meant to imply inevitability. As
Creighton, Ford and Mitchell (1993, p1340) describe that the extent of
illness and injury at work:
is often described in terms of an accident problem. This is accurate to a point. Many workers are indeed killed or injured through what the Oxford English Dictionary describes as ‘anything that
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happens without foresight or expectation, an unusual event which proceeds from some unknown cause, or is an unusual effect of a known cause’. However this definition cannot be accepted without reservation for present purpose. All too many workplaces and work processes are so dangerous that it is inevitable that someone will be injured at some time. The only things that are ‘unknown’ or ‘unpredictable’ are who will be injured, and when. Nevertheless, the term ‘accident’ is useful to the extent that it denotes a sudden, traumatic event such as a fall from a ladder, the amputation of a finger by power press or a massive exposure to a toxic substance. It should not, however, be used in such a way as to suggest that a given injury could not have been prevented. Nor should it be permitted to obscure the broader, structural dimensions of the problem of work-related injury and disease (Creighton, Ford et al., 1993).
In summary, this section provides an overview of the definitions and
mortality rate in relation to workplace health and safety as described by
existing and accessible national data collections. Even though most of
national data has limitations resulting in under reporting, the data
shows a considerable number of injuries occurring every day and every
minute in various workplaces. It also demonstrates that there are many
issues, which still have to be analysed and discussed. In particular,
much of the data available concentrates on the extent of injury in the
workplace. Little is known of the extent of occupational disease.
2.2.4 Occupational exposure to mercury and lead
2.2.4.1 Mercury toxicology8
Mercury toxicology has been widely reported (Gerstner & Huff, 1977;
Weening, 1980; Sharma & Obsersteiner, 1981; Wedden, 1983). This
Section will review the literature on the toxicology of mercury, the way
in which it may be absorbed into the body, and its effects on the body.
The major emphasis will be on occupational exposures. The major
route of exposure is through inhalation (World Health Organisation,
1991).
2.2.4.1.1 Properties of Mercury
Elemental or metallic mercury is an unusual metal because it is a liquid
rather than a solid at Standard Temperature and Pressure, and it
8 A criterion for inclusion of studies, which included reported mercury concentrations in urine, in this literature review was that they had been corrected or normalised for hydration state unless the sample was a composite over most of the day. The importance of normalising for hydration is discussed in Section 2.2.4.2.1.
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slowly evaporates at Standard Temperature and Pressure (Agency for
Toxic Substance and Disease Registry, 1999). It is a silvery,
odourless, heavy liquid with a saturated vapour pressure of 0.0018 torr.
Elemental mercury is present in the air of the workplace as a vapour,
but its salts are present as aerosols or particles (World Health
Organisation, 1980).
2.2.4.1.2 Absorption and Elimination of Mercury
Mercury is absorbed via the lungs, the skin, and the gastrointestinal
tract, the last of these usually being accidental (Foa, 1986). But
inhalation of mercury vapour is the most important route of uptake for
elemental mercury in the workplace (Hursh, Clarkson, et al. 1976;
Teisinger & Fiserova-Bergerova, 1965; World Health Organisation,
1976). Retention of elemental mercury in the respiratory tract and
lungs is significant with, less than 25 percent of the inhaled amount
being exhaled (World Health Organisation, 1980; Nakaaki, 1978) and
retention occurs almost entirely in the alveoli, where it is almost 100%
retained. The retained amount is the same whether inhalation takes
place through the nose or the mouth (Hursh, Clarkson, et al, 1976;
World Health Organisation, 1976). Dermal absorption of mercury
vapour was studied in volunteers by Hursh, Clarkson, et al. (1989). At
exposure of up to 50 µg/m3, the dermal penetration rate of mercury
vapours is about 0.072ng/cm2/hr, and this dermal uptake of vapours is
not likely to affect the biological levels significantly (Hursh, 1989).
However, Magos (1991) found that, dermal contact with liquid mercury
could significantly increase the biological levels.
9Toxicokinetic data on any chemical underpins the interaction of any
biological monitoring result in terms of the exposure it is reflecting (Droz
& Fiserova-Bergerova, 1992). The half-life of urinary excretion has
been reported as ~40 days in two studies with differing occupational
exposure scenarios (Barregard & Schuts, 1992; Skare & Bergstrom, 9 The study of the time-dependent processes related to toxicants as the interact with living organism. It encompasses absorption, distribution, storage, biotransformation and elimination.
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1990), 55days (Sallsten & Barregard, 1994), 70-90 days (Roles,
Boercks, et al., 1991; Ellingsen, Thomassen, et al., 1993) and as
short as 20days (Piotrowski, Trojanowska, et al., 1975). Mason,
Hindell, et al. (2001) have calculated half-lives of 83 days for a worker
removed from high chronic mercury vapour exposure and 76 days for a
woman removed from occupational vapour exposure because of
nephrosis It has been suggested that the reported variation in half-lives
of urinary excretion is due to individual factors, such as induction of
renal metallothionein10 , which binds mercury, and that higher initial
urinary mercury levels may lead to a longer half-life (Mason, Hindell, et
al., 2001). Applying the single compartment, pharmacokinetic model
calculation developed from a study by Droz and Fiserova-Bergerova
(1992) for likely half-lives of between 40 and 90 days, 20-25% of
cumulative exposure is excreted through the urine and contributes to
the mercury in urine value and only 10% the previous week’s exposure
contributes to the urine value.
In cases of recent, acute or widely fluctuating exposures, a urinary
mercury value cannot be as informative in estimating the extent of the
acute exposure as a blood mercury measurement taken at the correct
sampling time (Mason, Hindell, et al., 2001). The half-life of blood
mercury has largely been derived from acute single-dose exposure and
suggests at least two elimination phases consisting of an initial fast and
a longer elimination phase. The fast phase for mercury vapour has
been reported as ~ 3 days in experimental radio activity studies
(Cherian, Hursch, et al., 1978) and after acute exposures in the
chloralkali industry (Barregard & Schuts, 1992). These data may
suggest that the initial fast phase of elimination of blood mercury largely
reflects tissue uptake and excretion through the lungs (Cherian,
Hursch, et al., 1978). 10 Metallothioneins (MTs) are ubiquitous low molecular weight proteins and polypeptides of extremely high metal and sulfur content. They are thought to play roles both in the intracellular fixation of the essential trace elements zinc and copper, in controlling the concentrations of the free ions of these elements, in regulating their flow to their cellular destinations, in neutralising the harmful influences of exposure to toxic elements such as cadmium and mercury and in the protection from of a variety of stress conditions.
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Table 2.2 shows the average half-life for clearance of mercury from
various organs of the body following exposure by inhalation.
Table 2.2: The average half-life for clearance of mercury in the body (After: (Sherlock, Hislop et al., 1984)
Organs Half-life for Mercury (Days)
Lung 1.9 Brain 21 Chest 43 Kidney 64 Whole body 58
2.2.4.2 The Biological Monitoring of Mercury
2.2.4.2.1 Mercury in Urine
Measurement of mercury in urine is the recommended biologic monitor
for workers exposed to metallic and inorganic mercury (Lee, Kim et al.,
1990; Kim & Cha, 1990; Druet, 1991). Monitoring urinary mercury is
recommended not only as a non-invasive technique for obtaining
samples but also for its usefulness in assessing the risk of adverse
effects and the need for preventive measures (Barregard, Sallsten et
al., 1992).
Urinary mercury is a valuable indicator for average long-term exposure
and reflects integrated exposure over the preceding weeks or months
in workers (Barregard, Sallsten et al., 1992; Mason & Calder, 1994).
Ideally:
the collection should be over 24 hours, but this is seldom reasonable. Spot urine samples may also be taken, but care must be taken to always collect them at the same time of day near the end of the workweek after several months of steady exposure. Overnight samples may also be collected; this collection extends from the time the employee goes to bed through the first urination of the monitoring (National Academy of Science/National Research Council, 1989).
Urine mercury levels of up to 20 µg/L have been found in normal
human populations (Stokinger, Clayton et al., 1981).
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The World Health Organisation notes that:
Even when the rate of metal excretion is constant, metal concentration varies according to the urine flow rate (Diamond, 1988). It is therefore necessary to adjust the measured concentrations of metals in spot urine samples for variations in the urine flow rate. This can be done by correcting for urine relative density or osmolality or by dividing by the concentration of creatinine in the urine sample (World Health Organisation, 1991: 26).
Likewise, LaDow (1990: 464) notes that:
Unfortunately, significant variation can occur in spot urine levels owing to fluctuation in urine concentrations. This variability may be reduced by adjusting levels to urine specific gravity (SG 1.014) or urine creatinine (1 g creatinine). This standardization should be done on a case-by-case basis.
There is no way of converting from levels of mercury per litre of urine to
creatinine levels unless creatinine levels are reported11.
2.2.4.2.2 Mercury in Blood
The concentration of mercury in blood reflects exposure to organic
mercury as well as metallic and inorganic mercury; thus it can be
influenced by the consumption of fish containing methyl mercury
(Druet, 1991).
Samples should always be taken at the same time of day near the end
of the work week after several months of steady exposure. The blood
should be collected in mercury-free heparinized tubes after careful skin
cleansing (Nixon, Mussman et al., 1996; National Academy of
Science/National Research Council, 1989). Blood mercury levels of up
to 30-40 ng/ml are considered normal in human populations (Stokinger,
Clayton et al., 1981; Hursh, Clarkson et al., 1976).
Several studies have reported a correlation between mercury in blood and urine. The results vary considerably and it is not known whether the ration between concentrations in urine and blood is constant at different exposure levels. At low exposure levels the possibilities of a significant
11 Unless specifically noted, all studies cited in this report dealing with mercury concentrations in urine have been adjusted to allow for hydration.
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confounding effect on blood levels should always be borne in mind (World Health Organisation, 1991).
2.2.4.2.3 Biological Exposure Indices (BEIs)
Biological exposure indices are reference values intended as
guidelines for the evaluation of potential health hazards in the practice
of industrial hygiene. Biological exposure indices represent the level of
contaminants that are most likely to be observed in specimens
collected from a worker who has been exposed to chemicals to the
same extent as a worker with inhalation exposure at the threshold
limited value (TLV). The exceptions are the biological exposure indices
for some chemicals, namely those for which threshold limited values
are based on protection against non-systemic effect and biological
monitoring is desirable because of their potential for significant
absorption via an additional route of entry (usually the skin) (American
Conference of Governmental Industrial Hygienists, 2003).
BEIs apply to eight-hour exposures, five days a week. However, BEIs for altered work schedules can be extrapolated on pharmacokinetic and pharmacodynamic bases. BEIs should not be applied either directly or through a conversion factor, in the determination of safe levels for nonoccupational exposure to air and water pollutants or food contaminants. The BEIs are not intended for use as a measure of adverse effects or for diagnosis of occupational illness (American Conference of Governmental Industrial Hygienists, 1999)
Biological exposure indices and workplace exposure limits for mercury
and lead exposure have been established in a number of countries
including the US and Australia. In Korea, legislation stipulates that the
US standards should be followed for airborne exposure. Korea has
established its own biological exposure indices.
The health surveillance process and biological indices used in Korea
and Australia for mercury are discussed in detail later in this Chapter.
2.2.4.3 Airborne Exposure Limits
In the U.S. the Occupational Health and Safety Administration, the
National Institute for Occupational Safety and Health, and the
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American Conference of Governmental Industrial Hygienists have
recommended the following air monitoring standard levels:
OSHA (Occupational Safety and Health Administration):
The current OSHA permissible exposure limit (PEL) for mercury vapour is 0.1 mg/m3 of air as a ceiling limit. A worker’s exposure to mercury vapour shall at no. time exceed this ceiling level (Occupational Safety and Health Administration, 1994).
NIOSH (National Institute for Occupational Safety and Health):
The NIOSH has established a recommended exposure limit (REL) for mercury vapour of 0.05 mg/m3 (50 ug/m3) as a TWA for up to a 10-hour workday and a 40-hour workweek. NIOSH also assigns a ‘skin’ notation, which indicates that the cutaneous route of exposure, including mucous membranes and eyes, contributes to overall exposure (National Institute of Occupational Safety and Health, 1992).
American Conference of Governmental Industrial Hygienists):
The ACGIH has assigned mercury vapour a threshold limit value (TLV) of 0.025 mg/m3 as a TWA for an 8-hour workday and a 40-hour workweek. The ACGIH also assigns a ‘skin’ notation to mercury vapour (American Conference of Governmental Industrial Hygienists, 1994).
It is the Occupational Health and Safety Administration’s Permissible
Exposure Limit which is adopted in Korea. In Australia the Workplace
Exposure Standard has been set at a Time Weighted Average (TWA)
value of 0.05 mg/m3.
In Australia, the Exposure Standards Expert Working Group, under the
auspices of the Standards Developments Standing committee, has
been charged with the task of reviewing and recommending
occupational exposure standards for individual chemical substances
following consideration of the best available technical data from
Australian and a range of overseas sources (National Occupational
Health and Safety Commission, 1995).
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The exposure standards do not represent ‘no-effect’ levels, which guarantee protection to every worker. Given the nature of biological variation and the range of individual susceptibility, it is inevitable that a very small proportion of workers who are exposed to concentrations around or below the exposure standard may suffer mild and transitory discomfort. An even smaller number may exhibit symptoms of illness The exposure standard only considers absorption via inhalation and is valid only on the condition that significant skin absorption cannot occur (National Occupational Health and Safety Commission, 1995).
2.2.4.3.1 Rational for Limits
The NIOSH limit is based on the risk of central nervous system damage, eye, skin, and respiratory tract irritation (National Institute of Occupational Safety and Health, 1992) .
The American Conference of Governmental Industrial Hygienists
(ACGIH) has not published documentation for the current TLV for
mercury vapour. The 1991 Documentation for TLV (6th edition) discuss
the basis for the prior TLV of 0.05 mg/m3, but does not discuss the
current TLV for mercury vapour (American Conference of
Governmental Industrial Hygienists, 1991).
Methods for the monitoring of air borne levels of mercury vapour are
provided in a number of publications (Occupational Safety and Health
Administration, 1989; Park, Kim et al., 1989; Kim & Cha, 1990; Lee,
Kim et al., 1990; World Health Organisation, 1991; Ehrenberg, Vogt et
al., 1991; Hawkins, Norwood et al., 1991; Cha, Kim et al., 1992;
National Institute of Occupational Safety and Health, 1992; Agency for
Toxic Substance and Disease Registry, 1999), 1993 & 1992; (US
Environmental Protection Agency, 1994).
The rational for the Australian Workplace Health and Safety Standard
is based on the following publication by the American Conference of
Governmental Industrial Hygienists, 1986 Documentation of the
threshold limit values and biological exposure indices, 5th edition,
Cincinnati, Ohio. In 1991 the National Occupational Health and Safety
Commission deleted the skin notation from the exposure standard
(National Occupational Health and Safety Commission, c1991)
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2.2.4.4 Occupational mercury exposure
Industries in which occupational exposure to mercury may occur
include chemical and drug synthesis, hospitals, laboratories, dental
practices, instrument manufacture, and battery manufacture (National
Institute of Occupational Safety and Health, 1977). Jobs and
processes involving mercury exposure include manufacture of
measuring instruments (barometers, thermometers, etc.), mercury arc
lamps, mercury switches, fluorescent lamps, mercury broilers, mirrors,
electric rectifiers, electrolysis cathodes, pulp and paper, zinc carbon
and mercury cell batteries, dental amalgam, antifouling paints,
explosive, photographs, disinfectants, and fur processing.
Occupational mercury exposure can also result from the synthesis of
mercury catalysts (in making urethan and epoxy resins), mercury
fulminate, Millon's reagent, chlorine and caustic soda,
pharmaceutical's, and antimicrobial agents (Occupational Safety and
Health Administration, 1989).
The Occupational Safety and Health Administration (1975) estimated
that approximately 150,000 U.S. workers are exposed to mercury in at
least 56 occupations (Occupational Safety and Health Administration,
1975). More recently, Campbell, Gonzales, et al., (1992) reported that
about 70,000 workers are annually exposed to mercury in the U.S.
Inorganic mercury accounts for nearly all occupational exposure, with
airborne elemental mercury vapour the main pathway of concern in
most industries, in particular for those whose workers show the highest
levels of exposure.
A number of studies involving the monitoring of mercury workers
indicated a range of exposures. Some studies have reported
employees working in areas that contain extremely high air mercury
concentrations: 0.2 to over 1.0 mg/m3 of mercury. Such workplaces
include lamp sock manufactures in Taiwan (Yang, Huang et al., 1994),
mercury mines in Japan (Kishi, Doi et al., 1993; Kishi, 1994), a small
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thermometer and scientific glass manufacturer in the US (Ehrenberg,
Vogt et al., 1991), and a factory producing mercury glass bubble relays
(Gonzalez-Fernandez, Mean et al., 1984).
High mercury levels have been reported in blood and urine samples
collected from these employees (reportedly over 100 µg/dL in blood
and over 200-300 µg/L or 100-150 µg/g creatinine for urine depending
on the monitoring method employed) (Jang, Kim et al., 1989; Cha, Kim
et al., 1992).
Studies, covering industries where exposure has been high, have pointed towards the importance of urine mercury peaks in excess of 500 µg/litre for the development of neurological signs and symptoms (Langolf et al., 1978m 1981). Urine mercury peaks in excess of 100 µg per litre have been associated with impaired performance in mechanical and visual memory tasks and psychomotor ability (Forzi et al., 1976) (World Health Organisation, 1991, 87).
A study by Miller et al. (1975) (cited in World Health Organisation,
1991: 88) examined subclinical effects related to exposure to inorganic
mercury where mercury levels in urine varied from normal to over 1000
µg/L. “Neurological examination found evidence of eyelid fasciculation,
hyperactive deep tendon reflexes and dermatographia, but these
findings did not correlate with urinary mercury levels of length of
exposure.”
A number of studies have also attempted to discover a correlation
between the level of mercury in blood and urine. The World Health
Organisation (1991:63) reports on a study by Roels et al. (1987) where
personal monitoring was used and where detailed quality control
procedures were used and:
a good relationship could be established between the time-weighted exposure to mercury vapour and the daily level of mercury in blood and urine. Urinary levels of about 50 µg/g creatinine were seen after occupational exposure to about 40 µg/m3 of air. Such an exposure would correspond to about 17 µg/litre of blood.
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Other studies report the ratio between urinary mercury (µg/L or per g
creatinine) and mercury in air (µg/m3) has as a rule been 1 – 2 (World
Health Organisation, 1991).
2.2.4.4.1 Occupational Exposure to Mercury in Fluorescent Lamp Manufacturing Companies
Fluorescent lamps are widely used both domestically and
commercially, as they provide an energy-efficient source of lighting.
In Korea the majority of studies attempting to establish an association
between mercury vapour, urine mercury concentrations, and blood
mercury concentrations have been reported at workplaces in which
fluorescent lamps are made (Park, Kim et al., 1989; Jang, Kim et al.,
1989; Kim & Cha, 1990; Lee, Kim et al., 1990; Oh, Kim et al., 1990;
Lee, Cha et al., 1991; Bae & Cha, 1991; Cha, Kim et al., 1992; Lee,
Kim et al., 1993; Lee, 1998a). Most of these studies have found
instances of excessive mercury body burden among exposed workers,
in some cases the levels identified have been in excess of the
biological exposure Indices (Kim & Cha, 1990; Cha, Kim et al., 1992).
The findings of the above authors are summarised in Table 2.3.
Kim and Cha (1990) have found that the geometric mean of urinary
mercury concentration among 543 workers who were exposed to
mercury vapour in Korea was 84.3 µg/L (1.13 µg/L - 533.9 µg/L). The
distribution of workers by urinary mercury concentration showed that 26
workers (4.8%) were above the legislatively defined diagnostic criteria
level12 of 300 µg/L (Kim & Cha, 1990).
Cha, Kim, et al., (1992) reported that mercury concentration in urine of
15 workers (1.9%) in a Korean company of 792 workers involved in
fluorescent lamp manufacture exceed the diagnostic criteria level of
300 µg/L and 411 workers (51.9%) exceed the warning level of 100
µg/L. 12 In Korea and in Korean literature this is often referred to the mercury poisoning level. The author recognises that this is an arbitrary classification and persons with this level of mercury in their urine may or may not exhibit symptoms of mercury poisoning.
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Table 2.3: Studies of occupational exposure to mercury: An analysis of the scientific literature
Investigator (Date)
Country
Study design
Cohort size
Follow-up period
Exposure Major findings
Yoshida (1985)
Japan 27 male workers
Thermometer factories
The findings suggest that the determination of elemental mercury in urine may serve as a useful indicator for assessing levels of recent exposure to mercury vapour, as well as the level of inorganic mercury in the blood
Jang, Kim, et al (1989)
South Korea
Cross-sectional
130 1987-1988
Mercury in FLMC
A total of 7 cases of metal mercury poisoning in a fluorescent lamp manufacturing company was reported
Park, Kim, et al (1989)
" 254 Jan 1988-Mar 1989
Mercury in FLMC
The highest Hg concentration in air by sampling point was found at the floor of workplace (0.334 µg/m³) and next were at vacuum exhaustion pump (0.183 µg/m³) and breathing zone of workers (0.103 µg/m³) in order
Kim & Cha (1990)
" " 543 Jun 1989-Dec 1989
Mercury in FLMC
The geometric mean of air borne Hg concentration in a total 11 factories was 47.9 µg/m³ (5.8-352.2 µg/m³), six factories (54.5%) exceed the threshold limit value (50.0 µg/m³) The geometric mean of urinary Hg concentration among 543 workers was 84.3µg/L (1.13-533.9 µg/L), 26 (4.8%) workers were above the Hg poisoning level (300 µg/L)
Lee, Kim, et al (1990)
" - Jan 1988-Mar 1989
Mercury in FLMC
Stepwise multiple regression analysis showed that the airborne Hg consumption was affected by number of inferior lamps produced, frequency of Hg infusion, overtime, ventilator, Hg consumption amount per lamp, local exhaust ventilation system in order
Oh, Kim, et al (1990)
" Case -control
155 (100:E, 55:C)
Mercury in FLMC
Urinary Hg concentration of manual workers on average was 125.9 µg/L (5.0-469.0 µg/L) which showed 10 times higher than that of the office workers, and the blood Hg concentration of manual workers on average was 6.3 µg/L (0.2-60.2 µg/L) which was 6.6 times higher than that of office workers
Lee, Cha, et al (1991)
" Cross-sectional
50 1 year Mercury in FLMC
Urinary Hg level is not an absolute indicator in diagnosis of Hg poisoning and a sensitive method whitch can detect the early health effects of Hg need to be developed
Richard, Vogt et al (1991)
U.S.A. 84 Hg exposed workers+ 79 unexposed workers
Thermometer manufacturing facility
Urinary Hg level in the study population ranged from 1.3-344.5 µg/g creatinine, with eight (10%) participants exceeding 150 µg/g creatinine and three workers exceeding 300 µg/g creatinine, which indicates increased absorption of mercury among the thermometer workers. Thermometer plant workers reported more symptoms than did controls
Cha, Kim, et al (1992)
South Korea
Case-control
815 1 year Mercury in FLMC
Hg concentration in urine of 15 workers (1.9%) among 792 workers exceeded diagnostic criteria level of 300 µg/L. 411 workers (51.9%) exceeded warning level of 100 µg/L
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Investigator (Date)
Country
Study design
Cohort size
Follow-up period
Exposure Major findings
Lee, Kim, et al (1993)
" " 20 I year Mercury in FLMC
Significant negative correlation was found between urinary Hg concentration and days after quitting Hg exposure among17 Hg workers
Sallsten, Barragard, et al (1993)
Sweden 15 men 3 different chloralkali plants
The decrease in Hg in whole blood, plasma (p) and erythrocytes was best characterised by a two compartment model. The half lives of the slow phase in whole blood and plasma were longer, and the relative fractions of the slow phase were higher (about 50%) after long term exposure than those (about 20%) reported after brief exposure.
Ishihara and Ursushiyama (1994)
Japan 14 Japanese female workers
23months exposure
Mercury battery factory
Seven Japanese female workers exposed to mercury vapour at a concentration of <0.02 mg Hg/m3 were examined for inorganic (I-Hg) and organic mercury (O-Hg) concentration in urine, blood and hair after 0, 4, 8, 17 and 23 months of exposure The concentration of I-Hg and O-Hg in plasma and O-Hg in erythrocytes, increased significantly after 4 months of exposure and the high concentrations were maintained until the end of the study
Oh, Kim, et al (1995)
South Korea
Case-control
133 (70:E, 63:C)
I year Mercury in FLMC
Mean concentration of urine Hg (43.5 µg/L) in exposure group was 9 times higher than control group
Williams, Frumkim ,et al (2001)
U.S.A. 1956-1994
large chloralkali factory
Within an exposure category, concentrations of Hg in air were fairly constant for the first 20 years of the factory’s operation, but began to increase in the late 1970s. Employees working in the cell room had the greatest exposure estimates had significant correlations (p<0.001) with the urinary data and were well within the modelled range of concentrations of Hg in air
E: exposure group C: control group Hg: mercury FLMC: fluorescent lamp manufacturing company
Most of the studies performed in Korea only looked at the mercury
exposure levels by using cross sectional studies with short periods of
follow up. There is a lack of understanding regarding the trend of
mercury exposure levels of workers and the influence of the
management systems in place despite most of studies reporting
incidents of mercury poisoning every year.
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2.2.4.4.2 Occupational Exposure to Mercury Amalgam in Dental Services
Dental amalgam containing mercury has been in use since 1818
(Pelva, 1994). As early as 1830, the question of the hazards of dental
fillings was raised and the 'war of dental amalgams' continued for the
major part of the 19th century. During the 1920s and 1930s, claims
were made that mercury absorbed through different body organs was a
health hazard (Flenders, 1992). In the early 1970s, mercury vapour
was identified in the buccal cavity of people with dental fillings (Vimy &
Lorcheider, 1985; (Berlund, 1990; Fung & Molvar, 1992) as well as in
different body tissues (Snapp, Boyer, et al., 1989).
The greatest exposure to mercury for dentists comes from handling
amalgam for restoration, although storage and disposal of amalgam
and amalgam capsules are also important sources of potential
exposure (Maritn, Naleway et al., 1995).
Mercury is released during the placement and removal of amalgams
but the level of mercury vapour and amalgam particles can be kept well
below acceptable levels by the correct procedures (Eley & Cox, 1993).
Mercury vapour is released during the insertion, condensation and
carving of amalgam. This mercury can be measured in the expired air
and saliva (Derand & Johansson, 1983; Reinhardt & Boyer, 1983).
The removal of amalgam restorations by high-speed rotary instruments
can result in the evolution of both mercury vapour (Richards & Warren,
1985) and mercury containing amalgam dust (Brune & Hensten-
Pettersen, 1980; Richards & Warren, 1985), which may be inhaled by
the dentist and assistant. Raised mercury vapour concentrations have
been reported in the oral cavity and expired air of patients and
operators during the removal of old amalgam fillings (Richards &
Warren, 1985).
Mercury vapour exposure from dental amalgam production is reported
from many countries (Ritchie, Gilmour, et al., 2002; (Jokstad, 1990;
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Skare & Bergstrom, 1990; Nilsson, Gerhadsson et al., 1990; Akesson,
Schutz et al., 1991; Visser, Piper et al., 1991; Pelva, 1994; Steinberg,
Grauer et al., 1995; Pohl & Bergman, 1995; Barregard, Sallsten et al.,
1992; Echeverria, 1998; Soleo, Pesola et al., 1998; Lygre,
Gronningsaeter et al., 1998; Schuurs, 1999; Galic, Prpic-Mehicic et al.,
1999). Possible adverse effects of mercury vapour from amalgam
processing have been discussed in several studies of dental workers
(Jokstad, 1990; Skare & Bergstrom, 1990; Nilsson, Gerhadsson et al.,
1990; Akesson, Schutz et al., 1991; Nilsson, Gerhadsson et al., 1990;
Ott, Grimmeisen et al., 1991; Pohl & Bergman, 1995; Lonnroth &
Shahnavaz, 1995; Maritn, Naleway et al., 1995; Steinberg, Grauer et
al., 1995; Langworth, 1997; Soleo, Pesola et al., 1998).
A study by Ritchie, Gilmour, et al (1995) identified a number of adverse
effects among dentists, which could be associated with mercury
exposure. Lehto, Alanen, et al. (1989), Langworth, Sallsten, et al.
(1997), and Steinberg, Grauer, et al. (1995) found that the urinary
concentrations of mercury in dentists and other dental professionals
who used amalgam in their work were statistically significantly
elevated.
In Sweden, a symptom questionnaire study showed that the number of
mercury exposure related symptoms was statistically higher in the
dentistry group compared with an age- and gender-matched control
group (Langworth, 1997). Also, Steinberg, Grauer et al. (1995)
indicated that the urinary mercury levels in dental professionals in Israel
were significantly higher than those of a control group (2.39+/- 0.319
vs. 0.899+/-0.34 µg mercury/g creatinine). Although mercury levels in
all participants did not exceed the toxic limit, the above findings clearly
point to the need for a continuation of this type of assessment.
A number of studies into the potential toxicity to patients from exposure
to mercury vapour from dental amalgam fillings have included health
effects on the central nervous system, and kidney damage (Langworth,
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Elinder et al., 1991; Stadtler, 1991; Visser, Piper et al., 1991; Lygre,
Gronningsaeter et al., 1998; Bangsi, Ghadirian et al., 1998; Barregard,
Sallsten et al., 1992; Echeverria, 1998).
In West Germany, urinary mercury was determined in 22 dentists and
46 dental nurses and assistants working in 15 private dental clinics.
Urinary mercury was significantly correlated with the number of
amalgam fillings in the dental personnel (Zander, Ewers, et al., 1992).
However, Skare and Bergstrom (1990) in a study of 314 dentists and
dental nurses employed in public clinics and private practise in
Stockholm found that, on the average, the occupational contribution to
the total urinary excretion rate was small and of the same order as the
contribution from their own amalgam fillings (approximately 2 µg of
mercury/24h). There were, however, individuals showing excretion
rates close to the levels at which effects on the central nervous system
and the kidneys have been reported. A summary of exposure to
mercury in relation to dental work is presented in Table 2.4.
Table 2.4: Studies of amalgam exposure to dental staff
Investigator (Date)
Country
Study design
Cohort size Follow-up period
Exposure Major findings
Kingman, Albertini, et al (1998)
USA Cross-sectional
Adult military population of 1127 healthy males
- Amalgam fillings
It is estimated that, on average, each ten surface increase in amalgam exposure is associated with an increase of 1 µg/L mercury in urine concentration
Skare & Bergstrom (1990)
Sweden " 314 dental personnel in public clinics & private practice
- Amalgam Individuals showing excretion rates close to the levels at which effects on the central nervous system & the kidney have been reported
Jokstad (1990)
Norway - Dental personnel 672; 1986 273:1987
1986-87
Amalgam Elevated mercury values were observed for participants working in clinics with installed amalgam separators or other filtering devices
Ritchie, Gilmour, et al (2002)
Scotland Cross sectional
180 dentists, 180 control group
Amalgam Dentists had on average urinary concentrations over four times that of control subjects. Dentists were significantly more likely that control subjects to have had disorders of the kidney& memory disturbance. However as similar health effects are known to be associated with mercury exposure, it would be appropriate to consider a system of health surveillance of dental staff with particular emphasis on symptoms associated with mercury toxicity
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Investigator (Date)
Country
Study design
Cohort size Follow-up period
Exposure Major findings
where there is evidence of high levels of exposure to environmental mercury
Harakeh, Sabra, et al (2002)
Lebanon
99 Lebanese dentists
Amalgam Hg concentration in hair was significantly lower among the dentists who always used gloves and masks. Dentists who saw more than eight patients per day had marginally higher mercury levels in their hair that those who did not.
Langworth, Sallsten, et al (1997)
Sweden Case-control
22 dentists, 22 dental nurse 44; control group
Amalgam The number of symptoms was statistically significantly higher in the dentistry group compared with an age-and gender matched control group. Exposure to mercury in the dental profession in Sweden is low. The air Hg levels were mainly influenced by the method of amalgam preparation and inserting, and by the method of air evacuation during drilling an polishing
Michael, et al (2000)
U.S.A Cross-sectional
1277 dentists
1991 Amalgam Univariate analyses of professional practice characteristics with urinary mercury concentration showed that the number of years in practice and the number of years in the current office were significantly associated with urinary mercury concentration, as were the use of squeeze cloths and the number of amalgam placed per week.
Thomson, Stewart, et al (1997)
Australia NDTIS 5101 participants (Australian Public)
1995 There is substantial degree of concern about mercury and dental amalgam among the Australian public, but that the dental behavioural & treatment-pattern consequences of that concern are infrequent
Kazantzis (2002)
UK Literature review past 40 years
2001 Mercury Urine mercury levels of the order of 30-100 mg/g creatinine are objectively detectable tremor, psychological disorder and impaired nerve conduction velocity in sensitive subjects, with subjective symptoms of irritability, fatigue and anorexia. as mercury can give rise to allergic and immunotoxin reactions which may be generically regulated, in the absence of adequate dose-response studies for immunologically sensitive individuals, it has not been possible to set a level of mercury in blood or urine below which mercury related symptoms will not occur
Bake, Aulika, et al (2002)
Russia Cross-sectional
2001 Blood tests support that mercury has entered the workers’ body. Mercury concentrations of the dentist’s blood correlate with those in the air
Stenberg, Grauer, et al (1995)
Israel Case-control
Dental personnel
Amalgam Urinary mercury levels of the tested dental professionals were significantly higher that those of the control group (2.39± 0.319 vs. 0.899± 0.34 µg mercury/g creatinine). Of the dental personnel examined, 72% had detectable levels of urinary mercury, compared to 27% of the control group
Rowland, Baird, et al (1994)
U.S.A Questionnaire survey
418 registered dental assistants who had become pregnant
Jun 1987-May 1988
Amalgam Women with high occupational exposure to mercury were less fertile than unexposed controls. The fecundability of women who prepared 30 or more amalgams per week and who had five or more poor mercury hygiene factors was only 63% of that for unexposed women (95%CI; 42-96%) after
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Investigator (Date)
Country
Study design
Cohort size Follow-up period
Exposure Major findings
controlling for covariates Tezel, Ertas et al (2001)
Turkey Cross sectional
92 dental students, 16 clinical teachers, 14 controls
Amalgam There were statistically increased in plasma mercury concentration between measurements in all groups at the end of the academic year. Red cell mercury levels were also consistently elevated
Hamilton, Ritchie, et al (2000)
Scotland Epidemioloic study
150 dental surgeries
Amalgam Preliminary results from 150 dental surgeries showed that in 32% of surgeries the direct reading instrument displayed raised levels of mercury beyond that of the occupational exposure limit, as defined by the UK Health & Safety Executive
Rojas, Guevara, et al (2000)
Venezuela
66 dental personnel
1998 There was no correlation between the quantity of amalgam prepare and working hours with Hg-U and NAG-U.
Wilson, Bellinger et al (1998)
UK Summaries
Dental practice
It is concluded that occupational/ environmental management and auditing would be advantageous to dentistry
NDTIS : National dental telephone interview survey NAG-U: Urinary N-acetyl-beta-D-glucosaminidase Hg-U: Urinary mercury concentration level Fecundability: probability of conception each menstrual cycle
In summary, the levels of environmental mercury exposure found in the
studies reviewed above indicate that in many there is a relationship
between mercury exposure levels and biological results associated
with using amalgam in dental practice. Unless properly controlled the
use of amalgam in dental practices can expose dental workers to
elevated levels of mercury. The health impacts of mercury exposure
are discussed in the following section.
2.2.4.5 Health impacts of mercury exposure
The major concerns of relationship of mercury from amalgam to
possible ill effects have been (Eley & Cox, 1993; Mandel, 1993):
Kidney dysfunction
Neurotoxicity- classical problems associated in the past with
occupational exposure and speculative involvement in the
cause of multiple sclerosis
Reduced immuno-competence resulting in varied disorders
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Increased stillbirths and birth defects
General health
Mercury is known to have effects on the kidney and nervous system
and has been implicated in adverse effects on other systems including
the immune system and the female reproductive system (Dock &
Vahter, 1999; World Health Organisation, 1991; Eggleston, 1984;
Schuurs, 1999). Also several studies have shown that chronic
exposure to low concentrations of mercury may have an effect on
psychological performance (Echeverria, Heyer et al., 1995; Piikivi,
Hannien et al., 1984; Ngim, Foo et al., 1992; Roles, Lauwerys et al.,
1982; Uzzel & Oler, 1986).
Mercury vapour has caused concern as an occupational factor for male
and female reproduction and also toxicity for foetuses (Lauwerys &
Hoet, 1993; Fu & Boffetta, 1995; Rowland, Robinson et al., 1983; Dahl,
Sundby et al., 1999; Schuurs, 1999).
Some studies have shown that the incidence of birth defects, neonatal
asphyxia, neonatal death, infant infection, low birth weight, retardation
on physical and mental development in off-spring of the exposed
female were not significantly higher than in those of controls (Fu, 1993).
Also, increased rates of spontaneous abortions or congenital
abnormalities were noted in the children of men and women who were
exposed to low and high levels of mercury in a dental environment
(Dahl, Sundby et al., 1999).
However in contrast, females exposed to low-level mercury over a
long-term manifested dysmenorrhoea, and the incidence of
dysmenorrhoea increased with exposure dose (Fu, 1993). Elghany,
Stopford, et al (1997) have found that higher frequency of adverse
reproductive outcomes, especially congenital abnormalities, among the
women exposed to inorganic mercury levels at or substantially lower
than 0.6 mg/m3. In addition, experimental animal studies show
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exposure to mercury vapour or inorganic mercury compounds can
impair fertility (Rowland, Robinson et al., 1983) and that high
doses/concentrations of mercury, increase the risk of reproductive
disorders such as infertility, spontaneous abortion, stillbirth and
congenital malformations (Schuurs, 1999). Rowland, Baird, et al
(1994) have insisted that women with high occupational exposure to
mercury were less fertile than unexposed controls.
In summary, the effects of exposure to low doses of mercury are not
well established. The effects of mercury in high doses are much more
thoroughly established and include adverse effects on kidney function
and on the nervous system. Effects on reproductive health, particularly
at low doses, are not as well established but a number of studies have
reported such effects. As many dental workers are women of
reproductive age, the effects of mercury on developing foetuses should
also be of some concern.
The impact of exposure from dental fillings has also been discussed
briefly above. This area is filled with controversy and is discussed in
more detail in the following section.
2.2.4.6 Controversy of amalgam exposure
There have been considerable reductions in exposure to mercury
among the dental profession in recent years (Naleway, Sakaguchi et
al., 1985). These reductions are likely to have been the results of
mercury screening programmes, the use of automated methods of
amalgam preparation and improvements in mercury hygiene in dental
surgeries (Eley, 1997; Pohl & Bergman, 1995)
While concerns regarding mercury’s systemic toxicity have reduced
with decreasing urinary mercury levels detected in dentists over recent
years, continuing attention to mercury hygiene, particularly proper
amalgam storage, handling and disposal, is essential (Mandel, 1993).
Storage practices for excess mercury and excess amalgam by dentists
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were variable in one study (Leggat, Chowanadisai et al., 2001).
However, these practices appeared not to be entirely consistent with
guidelines published elsewhere, suggesting that these materials need
to be stored in a closed container under radiographic fixer (Mandel,
1993).
While Ritchie, Gilmour, et al. (2002) report that a study found the health
risk from amalgam restorations is negligible for most dental personnel
and patients, this author still maintains that the use of amalgam can
result in considerable adverse health effects.
More recently, there have been a series of published
statements/articles form the American Dental Association (ADA) and
Canadian Dental Association (CDA), all claiming that dental amalgam
are safe for use as a dental filling material. None of these
pronouncements referenced or provided any basic scientific research
showing the safety of amalgam. Since the majority of dentists in North
America rely on the guidelines of the leadership of the American Dental
Association, the Canadian Dental Association and the National Institute
of Dental Research (NIDR), it is imperative that such organisations be
scientifically accurate when they make statements to the profession,
which can affect public health (International Academy of Oral Medicine
and Toxicology, 1995).
Given the various approaches to the consequence of mercury
exposure in dental practice it would seem that the health situation of
dental workers, in relation to mercury exposure, requires further study.
2.2.4.7 Studies of mercury related occupational disease
The ubiquitous nature of mercury in the environment, its global
atmospheric presence and its toxicity to humans at levels that are close
to exposures levels, are of some concern (Hope & Ratcliffe, 1996). In
addition, the fact that estimates of risk to humans exposed to mercury
are often developed from animal studies not from population based
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epidemiological studies places even greater emphasis on the need to
carefully monitor mercury exposure and its possible health effects.
The United States EPA (US Environmental Protection Agency 1997)
estimates that, in the U.S.A., secondary production of mercury (ie.
recovering mercury from waste products) has increased significantly in
recent years. While 372,000 kg of mercury was used in industrial
processes in 1996, 446,000 kg was produced by secondary mercury
producers and an additional 340,000-kg were imported (US
Environmental Protection Agency, 1997). This is a two - fold increase
since 1991. The number of secondary mercury producers is expected
to increase as more facilities open to recover mercury from fluorescent
lamps and other mercury-containing products. As a result there is
potential for mercury emissions from this source to increase (US
Environmental Protection Agency, 1997).
Despite the research conducted on mercury exposure over the past
several years, essential data required for the risk assessment approach
to mercury exposure at low doses are lacking. There is evidence that
people who work with mercury have higher level of mercury in their
urine (Cha, Kim et al., 1992; Jang, Kim et al., 1989; Kim & Cha, 1990;
Steinberg, Grauer et al., 1995; Echeverria, 1998).
Most epidemiological studies of mercury workers have been cross
sectional studies (Cha & Yum, 1985; Lee, Kim, et al., 1990; Kim & Cha,
1990; Ehrenberg, Vogt, et al., 1991; Yoshida, 1985). The subtle
human health effects from prolonged exposure to small amounts of
mercury vapour are unknown. It has been difficult to study possible
effects of low-dose exposure for the lack of a good and reliable
measure of long-term exposure.
2.2.5 Lead
Lead is a soft, silvery-grey metal, melting at 327.5ºC. It is highly
resistant to corrosion, but reacts with nitric and hot sulphuric acids and
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the oxides are then taken into solution. The usual valence state in
inorganic lead compounds is +2. Solubility in water varies: lead
sulphide and lead oxides being poorly soluble and the nitrate, chlorate
and chloride salts are reasonably soluble in cold water. Lead also
forms salts with such organic acids as lactic and acetic acids, and
stable organic compounds such as tetraethlyl lead and tetramethyl
lead. (World Health Organisation, 2001).
Lead is not naturally found in the body. Although toxic effects of lead
have been known for centuries, lead poisonings is still wide spread in
the World (Medical Guidelines: The Lead-Exposed Worker, 2001).
A large number of reviews of lead toxicity have been published
(American Conference of Governmental Industrial Hygienists, 1989;
World Health Organisation, 1989; Lippmann, 1990). Lead poisoning is,
in most cases, a chronic disease. The toxic effects of lead for humans
can be viewed as a broad spectrum of laboratory and clinical
manifestations, ranging from subtle subclinical biochemical
abnormalities to severe clinical emergencies. In the beginning,
inhibition of enzymes and other biochemical effects occur. At the
intermediate stage, the effects of various enzyme inhibitions can be
measured, such as inhibitions of enzymes in the biosynthetic pathway
of haem or accumulation of enzyme substrates.
Lead toxicity disturbs the haem synthesis, erythrocyte survival, the
peripheral and central nervous system, the kidneys and the
gastrointestinal tract. Lead also affects reproduction, and possibly also
causes cardiovascular and mutagenic effects. The immune system is
also a target for sub-clinical lead-related toxicity (Fischbein, 1992).
Increased levels of serum erythrocyte protoporphyrin and increased
urinary excretion of coproporphyrin and delta-aminolaevulinic acid
dehydratase and dihydrobiopterin reductase are observed at lower
levels (World Health Organisation, 2001).
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Impairment of psychological and neurobehavioral functions has been
found after long-term lead exposure of workers. Electrophysiological
parameters have been shown to be useful indicators of subclinical lead
effects in the central nervous system. Peripheral neuropathy has long
been known to be caused by long-term high-level lead exposure at the
workplace. Slowing of nerve conduction velocity has been found at
lower levels. These effects have often been found to be reversible
after cessation of exposure, depending on the age of the exposed
person and duration of exposure (World Health Organisation, 2001).
Lead was classified as a possible carcinogen (Group 2B) in humans by
International Agency for Research on Cancer (IARC) in 1987
(International Agency for Research on Cancer, 1987).
2.2.5.1 Absorption
Routes of exposure for inorganic lead are inhalation and ingestion.
Lead is well absorbed by inhalation. Adults absorb about 10% of an
ingested dose through the gastrointestinal tract, in contrast to 50%
absorption for children. Once absorbed, lead is found in all tissues, but
eventually 90% of the body burden is bound to bone with a half-life of
many years. The majority of an absorbed dose is excreted through the
kidneys (Medical Guidelines: The Lead-Exposed Worker, 2001).
Lead is absorbed from the lung or gastrointestinal tract and is
distributed in the body in three main compartments: blood, soft tissues,
and bone. Ninety nine per cent (99%) of the lead in blood in bound to
red blood cells, and 1% is free in the plasma. The lead in plasma is
available for exchange with the soft tissues (kidney, bone marrow, liver
and brain) and bone/teeth. The skeleton represents an accumulating
reservoir containing approximately 95% of the body burden of lead in
adults (Barry, 1975).
Inhalation is the primary route of entry for lead into the body in lead
workers. About 50% of inorganic lead deposited in the lung is
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absorbed. This is usually in the form of lead dust or lead fume (Kyle &
Boffetta, 2000). Pulmonary deposition of lead particles suspended in
air varies as a function of particle size distribution and respiratory rate.
Particles with an aerodynamic diameter above 5 µm are mainly
deposited in the upper airways, cleared by the mucociliary mechanism,
and swallowed (World Health Organisation, 1996). Particles with
diameter below 1 µm are deposited, to a large extent, directly in the
alveolar region of the lung. From radioactive and stable isotope studies
it can be concluded that lead deposited in the deep lung is completely
absorbed (Chamberlian, 1985; Morrow, Beiter et al., 1980).
Ingestion is the next most important route of entry. In contrast to lead
in the lungs, only about 10% (1.3-16%) of ingested lead is absorbed
from the gastrointestinal tract in adults. Ingestion is much less
significant for lead workers than inhalation. However, in smokers and
workers with poor personal hygiene, ingestion can play an important
role (Kyle & Boffetta, 2000).
Absorption of 0% to 0.3% is observed thought the skin and lead nitrate
solution placed on the arm can be absorbed through the skin and
rapidly distributed throughout the body. The transport occurs in plasma
and may be rapidly concentrated into the extracellular fluid pool of
sweat and saliva without significant uptake by erythrocytes (Florence,
1988).
The mean residence time in cortical bone is 30 years. Lead stored in
bone may be released under conditions of pregnancy, lactation,
immobility, thyrotoxicosis and other states where demineralisation of
the skeleton may occur, resulting in endogenous exposure (Goldman,
White, et al., 1994; Silbergeld, Schwartz, et al., 1988)
Placental transfer of lead occurs readily, placing the foetus of a female
lead worker at high risk (US Environmental Protection Agency, 2001).
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2.2.5.2 Distribution
The total burden of lead is distributed throughout various parts of the
organism, and the biological activity of lead varies between these
segments as well. The rapidly exchangeable portion of lead in plasma
is the most biologically active part of the total body burden, but it must
be emphasized that this pool constitutes only about 0.1% of the total
(Rabinowitz, Wetherill et al., 1976; Marcus, 1985).
There are rapid compartments (reflecting soft tissues) with a half-life of
about one month and a slow one (reflecting the bone pool) with a half-
life of approximately one decade (World Health Organisation, 1996).
Under experimental exposure conditions in adult volunteers, the mean
residence time of lead in the blood has been measured at
approximately 25 days. Most of lead in blood was excreted via urine.
One fourth went to soft tissue, with a mean residence time of 40 days,
after which it was excreted in bile, hair, sweat and nails. A smaller
proportion of the blood lead was deposited in bone (Rabinowitz,
Wetherill, et al., 1976).
2.2.5.3 Elimination
There are two main routes of lead excretion,
Renal, by glomerular filtration; and
via the gastrointestinal tract, by biliary execration, glandular
secretion and shedding of epithelial cells (US Environmental
Protection Agency, 2001).
There are also minor routes of elimination via sweat and hair. The
percent eliminated by each route depends on the route of absorption,
age of the individual, dietary constituents, and other variables. Ninety
percent (90%) of the ingested lead is excreted unabsorbed in the
faeces. About 76% of absorbed lead is excreted in urine, 16% in
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gastrointestinal secretions and less than 8% in hair, nails and sweat
(World Health Organisation, 1996).
2.2.5.4 Health Impacts of Lead Poisoning
Lead is highly toxic element that, when inhaled or ingested as lead
dust, paint chips or drinking water, is stored in human tissue, blood and
bone marrow. It can build up in the body until symptoms and disability
can occur. If the level of lead in the body gets too high, it can cause
loss of appetite, constipation, diarrhoea, loss of weight, severe
abdominal pains, muscle weakness, limb paralysis, headaches,
tiredness, and irritability (Staudinger & Roth, 1998; Division of
Workpalce Helath and Safety (Qld), c. 2001). Continued exposure or
high levels of exposure can have far more serious effects such as
anaemia, kidney damage, reduced male fertility, nerve and brain
damage (Division of Workpalce Helath and Safety (Qld), c. 2001).
Lead toxicity affects the hematologic, renal and neurologic systems
(Sanborn, Abelsohn et al., 2002). The neurotoxic effects of lead are
perhaps the best known and studied (Needleman, Schell et al., 1990;
Bellinger, Leviton et al., 1987).
Lead is not genotoxic in vitro, but increases the mutagenicity of other
mutagens, possibly acting via inhibition of DNA repair (Hartwig, 1994).
In adults, the effects of high-dose exposure to lead have long been
recognized and described (Landrigan, Silbergeld et al., 1990). The
clinical picture is characterized by anaemia, abdominal colic, peripheral
neuropathy (extensor weakness, “wrist/ankle drop”), and central
neuropathy with toxic encephalopathy, nephropathy, and sterility. With
very severe poisonings, the frequency of which has decreased in
recent years, tremors, stupor, intractable seizures, and coma may
result when blood lead levels rise rapidly to exceed 100 µg/dL (Levin &
Goldberg, 2000).
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Workers with lower-level, chronic or recurrent exposure to lead may
remain asymptomatic or develop vague, non-specific symptoms (e.g.,
myalgias, fatigue, irritability, headaches) reflecting more subtle in acute
intoxications (Agency for Toxic Substance and Disease Registry, ; U.S.
Department of Health and Human Services). Late effects may include
chronic renal failure, hypertension, gout and chronic encephalopathy
(Landrigan, Rosenstock et al., 1994). The general signs and
symptoms associated with lead toxicity are summarised in Table 2.5.
Table 2.5: General signs and symptoms of lead toxicity
Mild Moderate Severe Myalgias Irritability Paresthesia Mild fatigue Intermittent abdominal pain Lethargy
Headache Tremor Vomiting General fatigue Diffuse abdominal pain Weight loss Loss of libido Constipation
Encephalopathy Motor neuropathy Seizures Coma Abdominal colic Lead lines Oliguria
After: Agency for Toxic Substances and Diseases Registry, 1993.
Lead toxicity can be manifested clinically in multiple organs. Specific
organ system dysfunction includes the central and peripheral nervous
system, and renal hematologic, gastrointestinal and reproductive
systems. Figure 2.1 provides a summary of the organ-specific effects
associated with the lowest obstacle lead levels in the adult workers and
for comparison, in children.
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Children Lead concentration in blood µg/Dl
(µmol/L)
Adults
Key
% : Increased function
& : Decreased function
Figure 2.1: Effects of inorganic lead on children and adults (lowest observable adverse-effect levels) (After: ATSDR 1993)
2.2.5.5 Biological Exposure Indices
There are several reviews on biological monitoring of inorganic lead
exposure (Skervfing, 1988; Lauwerys & Hoet, 1993). Several
laboratory tests are available for evaluating the degree of lead
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absorption and related health effects. The biological tests that have
been used can be classified into two groups:
those directly reflecting the exposure and/or the amount stored
in soft tissues (lead in blood, in urine, in teeth and in hair, and
lead excretion after the administration of a chelating agent), and
those indicating the biological effects of lead related to the
intensity of exposure (coproporphyrin in urine, delta-
aminolevulinic acid in urine, porphobilinogen in urine, free
erythrocyte protoporphyrin (FEP) or zinc protoporphyrin (ZPP),
delta-aminolevulinic acid dehydratase (ALA-D) and pyrimidime-
5’-nucleotidase in red blood cells) (World Health Organisation,
1996).
At present, the blood lead concentrations are the best available
indicator of current lead absorption or dose and health risk, and blood
lead measurement is the mainstay of biological monitoring worldwide
(Agency for Toxic Substances and Disease Registry. 1993; Sussell,
Ashley, et al., 1997; Agency for Toxic Substances and Disease
Registry, 1999; Agency for Toxic Substances and Disease Registry,
2000). This generally reflects exposure in the last 2 to 3 weeks
(Medical Guidelines : The Lead-Exposed Worker, 2001). However
blood lead levels are poor indicators of total body burden. Because
blood lead concentrations increase quickly after inhalation or ingestion,
they are useful as a guide to the need for preventive interventions to
reduce exposure (Flegal & Smith, 1992).
As the blood lead level increases, the frequency and severity of
symptoms associated with lead exposure also increase (albeit with
considerable variability). With other indices of lead exposure, no such
specific relationship with symptoms has been established (Sussell,
Ashley, et al., 1997; Agency for Toxic Substances and Disease
Registry, 1999; Agency for Toxic Substances and Disease Registry,
2000). However, other causes of elevated protoporphyrin levels exist
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(e.g., iron-deficiency anaemia and inflammatory conditions) and these
can act as confounders (Stanton, 2000).
Lead concentrations can be measured in urine, teeth, and hair, but
these measurements are not as reliable as blood lead levels.
Among other indices, the indirect biological response test, such as ZPP
(zinc protoporphyrin), FEP and ALA-D concentrated in red blood cells
can be an accurate indicator of inhibition of haeme synthesis by lead
for assessing lead-related biological effects. It reflects exposure in the
last 3 to 4 months and rises and falls more slowly than the blood lead
level. This effect can begin at a blood lead level as low as 20 µg/dl in
adults (Medical Guidelines: The Lead-Exposed Worker, 2001).
For occupationally exposed workers and community groups whose
exposures are not well-characterized or in countries where the
availability of blood lead determination in limited, measurements of
ZPP and FEP are recommended for screening purpose. The ZPP test
can be performed at the examination site and has much practical
value. Elevated values of ZPP must be verified by measurement of
blood lead concentration, which is more specific to the current degree
of lead absorption (World Health Organisation, 1996).
Blood lead levels associated with exposure to only the natural lead
concentration in the biosphere, without the contribution from industrial
sources, are estimated to range from 0.06 to 0.12 µg/dL (Flegal &
Smith, 1992). While the second United States National Health and
Nutrition Examination Survey (NHANES II) in 1976 found a geometric
mean blood lead concentration of 12.8 µg/dL for the U.S population,
NHANES III in 1991 found a marked decrease to 2.8 µg/dL, largely due
to the removal of lead from most gasoline and from soldered cans
(Brody, Pirkle, et al., 1994). Levels in excess of 10 µg/dL are now
considered to reflect exposures above “background” (Levin & Golberg,
2000).
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Because of lead’s importance as a cause of not only occupational
health but also public health problems, health surveillance
requirements for lead in Australia, Korea and number of federal
agencies in the U.S.A. have issued advisory standards or enforceable
regulations that set lead levels in different media. Table 2.6
summarises these standards and regulations in the U.S.A.
Table 2.6: Summary of health surveillance standards and regulations for lead in U.S.A.
(Agency for Toxic Substances and Disease Registry., 1993)
Those for Australia are discussed in detail later in this Chapter. The
biological exposure indices for lead in Korea are presented in Table
2.7.
Table 2.7: Reference level of lead exposure in blood in Korea
(Korean Enforcement Regulations for Industrial Safety and Health Act 1997)
The U.S. Occupational Health and Safety Administration defines that
as a blood lead level > 40µg/dL is excessive exposure. The
Occupational Health and Safety Administration general industry lead
standard (29CFR 1910.1025) requires lowering the PEL (Permissible
Exposure Level) for shifts longer than 8 hours, medical monitoring for
employees exposed to airborne lead at or above the action level of 30
µg/dL, medical removal of employees whose average blood lead level
is 50 µg/dL or greater, and pay retention for medically removed
workers. Medically removed workers cannot return to jobs involving
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lead exposure until their blood lead level is below 40 µg/dL.
(Occupational Safety and Health Administration, 1978).
The American Conference of Industrial Hygienists has recommended
that worker lead exposure be kept below 50 µg/m³ (as an 8-hour TWA),
with worker blood lead levels to be kept less than or equal to 30 µg/dL
(American Conference of Governmental Industrial Hygienists, 1995).
To protect lead-exposed workers, a World Health Organisation study
group recommended a biological exposure limit of 40 µg/dL in 1980,
and further recommended that blood lead levels in women of
reproductive ages should not exceed 30 µg/dL (World Health
Organisation, 1980).
High exposure has occurred among workers in lead smelters and lead
battery plants (50-5000ug/m3 in air, 40-100ug/dl in blood) (Fu &
Boffetta, 1995). Moderate exposure has occurred among welders of
metals containing lead or painted with lead (lead fumes), lead glass
workers, lead miners, workers repairing automobile radiators, printers
using lead type, and production workers using lead (e.g., producing
lead chromate paint) (50-1000 ug/ m3 in air, 20-60 ug/dl in blood).
Occupational Safety and Health Administration (OSHA) limits for
airborne level are 50 ug/m3, and blood levels must be kept below
40ug/dl (Kyle & Boffetta, 2000).
2.2.5.6 Airborne Exposure Limits
Australia has set a Workplace Exposure Limit for lead, inorganic dusts
and fumes (as Pb) at a Time Weighted Average (TWA) value of 0.15
mg/m3 (National Occupational Health and Safety Commission, 1995).
2.2.5.7 Occupational lead exposure
Lead is the most widely used non-ferrous metal. The hazards from
lead in a wide range of industrial settings, and between 100 and 200
different occupations and job titles (Table 2.8) are considered to be
associated with a potential risk of exposure (Hernberg, 1975). Workers
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are exposed to lead in numerous work tasks, including motor vehicle
assembly, panel beating, battery manufacture and recovery, soldering,
lead smelting and lead mining, lead alloy productions, and in the glass,
painting, ceramics and paint industries (von Schirnding, 2001). The
major uses are for electric storage batteries, paint pigment, petrol
additives, various metal products, and as cable sheathing (World
Health Organisation, 1996).
Other occupations where workers have been shown to be at particular
risk include battery manufacturing, demolition, welding, pottery and
ceramic ware production, which is often a home-based occupation
involving women and children, small business repairing automobile
radiators and artisans producing jewellery and decorative wares. This
latter industry is of particular concern since it is predominantly carried
out at home or in non-regulated shops, often by women and children
(von Schirnding, 2001).
Examples of common sources of lead exposure are listed in Table 2.8.
Table 2.8: Common sources of lead exposure (Sanborn, 2002 #108)
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2.3 The legislative framework of occupational health and safety in Korea and Australia
Occupational health and safety regulation aims to reduce work-related
injury and disease by changing workplaces and work practices
(Industry Commission, 1995).
Two Scandinavian countries, Sweden and Denmark, have developed
particularly innovative approaches to workplace health and safety. The
UK is the system on which Australian legislation is modelled. The U.S.
has adopted a radically different approach which provides a valuable
contrast, and both the US and Canada offer important but very different
models which are similar to Korean model of how a federal system
might approach workplace health and safety.
The UK, Sweden and Denmark are examples of unitary systems where
workplace health and safety is addressed at the national level and all
significant legislation is national legislation. As models they are of
limited value in the Australian context as they are nationally based in
nations without state jurisdiction.
In contrast, both the US and Canada have had to grapple with defining
state/province-federal roles in workplace health and safety (Industry
Commission, 1995).
All jurisdictions under study believe that equity and efficiency dictate
that uniform legislation should be implemented to ensure
comprehensive occupational health and safety protection for all
workers and in respect of all workplaces. This has been substantively
achieved in all the jurisdictions under study although the drafting
techniques utilised for this purpose differ somewhat between countries
(Industry Commission 1995).
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The major occupational health and safety statues in many advanced
nations are now some 15 to 25 years old (Walters, 1996; Baldwin &
Daintith, 1998; Vogel 1998).
This section of the literature review outlines the history of the
development of the legal framework in Korea and Australia.
2.3.1 Occupational health and safety Regulation in Korea
To regulate industrial accidents and occupational disease the first legal
obligations were set out in Chapter VI (Article 64 to Article 73) of the
Labor Standards Act in 1953. However, due to a rapidly growing
Korean economy, the Articles of the Labor Standards Law were
insufficient to regulate the rapid increase in industrial accidents.
Specific and practical laws to regulate industrial accidents and
occupational disease, aside from the already existing Labor Standards
Act 1953, were required. As a result, the Industrial Safety and Health
Act and the Pneumoconiosis Act were established in 1981 and 1984
respectively.
These Acts and their associated regulations have served to secure the
safety and health of workers and to improve the working environment.
These two Acts clearly set out specific obligations for safety and health
within organisations and outline practical measures for the prevention
of hazardous working conditions, and the establishment of an
inspectorate for the enforcement of safety and health standards.
In response to the Industrial Safety and Health Act 1981, the Korean
Employers’ Federation (KEF) established a framework for occupational
safety and health in 1981 in an endeavour to improve employers’
understanding of the legislation.
The Korean Industrial Safety Corporation (a government owned
corporation charged with a range of responsibilities including
education, research, inspection, testing, technical advisory services,
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and data collection with respect to safety and health) was set up under
the Ministry of Labor in 1987. In the same year, the Industrial Safety
Bureau (renamed the Industrial Safety and Health Bureau in 1998) was
set up in the Ministry and Industrial Safety Divisions were established in
the local offices (Department of Labor [Korea], c 1999).
As Labor-management relations changed dramatically in the mid
1980s, the Korean government reviewed and revised its Labor laws,
and the general provisions of the Industrial Safety and Health Act. The
Industrial Safety and Health Act was totally revised in 1990 and was
further amended in 1995 and 1996.
In 1980 the Korean government “enacted the Labor-Management
Council Act, which made it mandatory for workplaces with trade unions
and all business with more than 100 workers to set up a Labor-
Management Council. Amendments to the Act in 1987 expanded the
coverage to all businesses with more than 50 workers (Department of
Labor [Korea], c1999: 34)”. In 1997 the Act was further amended to
encompass all workplaces with 30 or more employees regardless of
the presence or absence of a trade union. It is a requirement of this
legislation that consultation on a number of issues, including
improvement of working environments (safety, health, etc.) and
increasing workers health, takes place in the Council before
management implements related decisions.
The Korean Employers’ Federation established its own Occupational
Safety and Health Department in 1993. As a result of the requirements
of legislation and the efforts of this body, the concept of process safety
management and the promotion of chemical safety through the
requirement for the provision of chemical safety information sheets
became widely accepted and are said to have reduced occupational
accidents by 5 percent and fatality rates by 20 percent (Department of
Labor [Korea], c1999).
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The law requires that enterprises with 50 or more workers should
employ plant physicians to carry out occupational health related tasks
ranging from investigation of work environments to health education
and medical examination, done in cooperation with health managers –
nurses, hygienists and primary health care workers.
The Group Occupational Health Service System was launched at the
beginning of the 1990s by legislation enacted in order to improve
occupational health and safety for underserved workers employed in
small and medium-sized enterprises and to relieve the employer of the
economic burden incurred in hiring occupational health personnel.
Factories employing less than 300 workers (less than 1,000 workers
since 1998) can rely on this system instead of employing factory
doctors, nurses or hygienists. They are entitled to the benefit of regular
services, according to a monthly schedule,
There were 66 group occupational health service institutions covering
9,465 industries and 944,000 workers in 1996. Most institutions in this
system are supported by medical schools. Factories maintain close
contact with the institution, receiving advice and cooperation.
Under the Act, annual environmental monitoring at the workplace and
annual medical examinations for plant workers are carried out. In
particular, medical examinations for workers exposed to chemicals are
carried out twice a year or more.
The Industrial Safety and Health Act 1996 (Korea) also sets out
requirements for safety and health management systems. This is
limited to requirements for certain organisations employing between 50
and 100 persons to appoint a Safety and Health Management Officer13
(Article 13.1) to have general control over a range of health and safety
matters. Under certain circumstances a Safety Manager (Article 15)
and/or a Health Manager (Article 15) must also be appointed to advise
13 These are widely known as Safety and Health Officers.
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the employer on technical matters with respect to safety and health
respectively. The Act also sets out educational requirements for
persons with particular health and safety responsibilities in the
workplace.
Occupational health and safety in the majority of small factories (less
than 50 workers) are not covered by the law. Needless to say, those
workers have many problems involving health and safety in their work.
The government has a limited number of Labor inspectors, and they
cannot supervise or advise all of the factories in their district. Most
plant physicians are part-time physicians. In small factories the
activities of primary health care workers, who are not always qualified
nurses and hygienists, are often ineffective (Korean Occupational
Safety and Health Agency, 2001).
Workers in small factories constitute the majority of the nation’s
workforce. These small plants have many occupational health
problems. They have poor working conditions which result in high
rates of accidents and diseases. They are not financially able to invest
in health services. This situation creates further constraints in the
delivery of health and safety services (Korean Occupational Safety and
Health Agency, 2001)
In general, employers lack knowledge of, and interest in, occupational
health. In many instances, workers themselves do not realise the
importance of their health care and fail to participate actively in
education programmes.
Legislation in 1997 alleviating the restriction of industrial activities also
eased the duty to assign a safety and health supervisor and a public
health doctor and extended allowance of vicarious execution of safety
and health management. And so it caused weakening of safety and
health management systems in the workplaces and deteriorated the
service quality being provided to the workers.
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2.3.1.1 Hazardous substances legislation
This section will review the legislation relating to hazardous substances
in Korea with special emphasis on the health surveillance system for
mercury exposed workers.
The Korean legislation is prescriptive in nature and requires both
exposure monitoring and health monitoring of workers.
As stated above, the first occupational health and safety requirements
were introduced into Korean legislation in 1953. In 1963, this
legislation was strengthened with the requirement for medical
assessments of workers in dangerous industries. Starting in 1972,
special health checkups were required for workers exposed to
hazardous working conditions. In 1981, the Industrial Safety and Act
was established to complement the Labor Standards Act. In 1990, the
Industrial Safety and Health Act 1981 was amended to include the
requirement for a health surveillance system for small-scale industries
which include fluorescent manufacturing companies.
As a result of these legislative requirements, Korea has had in place a
system for monitoring the health of workers in hazardous industries for
over thirty years.
2.3.1.1.1 Specific Requirements
The Legislation requires that four types of periodical health
examinations be provided for workers14. These are:
Health check-up upon recruitment,
General health check-up,
Special health check-up,
Extraordinary health check-up.
14 These and the following requirements summarized below are set out in Articles 98-105 of the Korean Enforcement Regulations for Industrial Safety and Health Act 1997.
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Health check-ups upon recruitment are performed on workers who
are newly recruited for any job. The target populations for the general
health check-ups are workers who are not working at hazardous
workplaces, and in this case, blue colour workers are examined once a
year, while white colour workers are examined once every two-years.
Special health check-ups are performed on workers exposed to
hazardous conditions or materials such as lead, mercury, alkyl lead,
solvents, special designated chemical substances, noise, dust or
special dust, eg, cotton dust, high pressure indoor work, diving,
abnormal pressure, ionising and non-ionising radiation, and vibration.
Special health checkups are designed to assess occupational diseases
and symptoms that are related to the particular hazard in the
workplace. Such check-up may occur once or twice each year.
Extraordinary health check-ups are conducted for the workers who
have been accidentally exposed to hazardous materials or gases.
2.3.1.1.2 Blood and Urine Levels for Mercury
Under the Korean Regulation, if there is significant mercury level in
urine at the first round test, workers are tested a second time for both
mercury in urine and mercury in blood. Other tests, including
neurological tests, which may support the findings of the second tests,
may also be performed at this stage by on the recommendation of the
occupational health physician.
The requirements for Special Health Check-ups are defined by
Regulation in Korea as follows;
It is mandatory that all workers required to have a Special Health Checkup have this once per year. In exceptional cases, workers are required to have these examinations twice per year. Exceptional cases include those cases where:
• mercury in air levels exceeded the Reference Level (0.025mg/m3, and/or
• the worker/s was/were found to have occupational disease related to mercury exposure (Korea Labor Institute, 1993).
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2.3.1.1.3 Compulsory Health Check-up Items
The following information is collected as part of the compulsory general
and special health checkups conducted on workers exposed to
mercury in the Fluorescent Lamp manufacturing companies:
History of service and exposure;
Past history;
Self-symptoms: self administered symptom questionnaire;
Physical exam: skin, neuro-psycho, kidney, mouth;
Laboratory findings:
o Blood test (Hgb, Hct)
o Urine test (proteinuria)
o Liver function test (serum GOT, GPT, γ-GT);
Biological monitoring (mercury in urine - annually once worker
has commenced job and also before commencing job).
2.3.1.1.4 Optional Health Check-up Items
In addition, the following tests may be undertaken:
Kidney function test (ESR, proteinuria, creatinine, BUN)
Neurologic test
Biological monitoring mercury in blood – at the end of the work
week
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2.3.1.1.5 Outcomes
The following descriptions are given of the health status15 of workers
and these can be used to indicate treatment or follow up surveillance;
A normal,
B generally normal but some health attention needed
does not need medical treatment,
C need to be aware of heath status,
if necessary medical treatment required,
D2 diagnosed with general diseases,
medical treatment required.
D1 diagnosed with occupational diseases or with symptoms,
R difficult to diagnose further health examination required.
Workers classified as D1 are entitled to:
industrial accident benefits;
a change in the working department;
a change in workplace;
temporary absence from work, and/or
treatment while working can be suggested by a specialist in
occupational health or occupational medicine.
The medical, environmental, and occupational history interviews, the
physical examination, and selected physiologic or laboratory tests that
were conducted at the time of placement under the obligations of the
Industrial Safety and Health Act 1996 (Korea) for special health check-
ups are recorded on a standard form. Results of all monitoring are 15 These descriptions have been changed since the commencement of this study. The descriptions given herr are those relevant at the time of the collection of the biological samples.
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required by the legislation to be communicated to the employer on a
standard form within 30 days. Where anyone is judged to have an
occupational disease, the physician is required to immediately notify
the local Labor Office.
The diagnosis of an occupational disease may be based on symptoms
or on the level of mercury detected in the blood or urine of a worker. A
concentration of mercury >300 µg/L in urine or >20 µg/dL in blood is
known as a diagnostic level and is an indicator of mercury poisoning.
As noted above, most health surveillance in Korean workplace is
conducted in association with medical schools. In the case of mercury
surveillance, the Department of Preventive Medicine & Institute for
Environmental Health College of Medicine, Korea University conducted
the surveillance. This organisation has a special health service team
including a nurse, occupational physician, laboratory technician, and
administrator. There are two ways in which special health exams are
done. Firstly, if there is small numbers of workers are required to do a
health exam, the workers usually come to a clinic, but if there are more
than 50 workers requiring check-up, the workers are visited by a
special health service team at their workplace for the health
surveillance.
On the Health Surveillance Form information about age, sex, visual,
hearing test, blood pressure, general urine and blood test such as urine
protein, urine sugar, hematocrit, hemoglobins, serum GOT/GPT,
cholesterol, FBS, and chest x-ray are recorded every 2 years. These
tests are all part of the general health check-up. In addition, mercury
level in urine is included once a year for every worker who may have
been exposed to mercury as part of the extra testing required as part of
the special medical exam. If there is an elevated mercury level in urine
(≥100 µg/dL) the subject is required to be tested again for mercury in
urine as well as for mercury level in blood. These latter tests must be
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conducted within three months of the first test. Other, additional tests
may be undertaken at the discretion of the examining doctor.
A level of mercury in urine ≥100 µg/L or 3.5 µg/dL in blood is known as
a Warning Level. The Baseline Level is considered to be a mercury
concentration of <100 µg/L in urine or <3.5 µg/dL in blood.
If an elevated mercury in urine result is obtained in the first test, the
employer is required by Regulation to take steps to reduce the level of
mercury exposure to the individual.
2.3.2 Occupational health and safety Regulation in Australia
The 1960s to 1980s period was one of major restructuring for capitalist
economics, arising from the introduction of information technology into
manufacturing. The new industries also brought new hazards and
health problems. There was growing concern at the level of
occupational accidents, injury and disease, and evidence that these
were increasing.
Existing regulatory agencies were unable to effectively deal with the problem. Levels of penalties and enforcement were inadequate and Australian standards were often less stringent than in other countries. Lack of information on occupational health and safety matters was a major problem in Australia in the early 1970s.
Economic conditions also caused workers to turn their attention to broader social issues. From the mid-1970s inwards the economy was in recession, unemployment was rising and working conditions deteriorating. Poorly organised workers, often migrants who did not know their rights and had little English, were unprotected. Worsening conditions produced high injury rates which, when they became pollitised, became significant occupational health ad safety issues. Better-organised workers were more protected but because of the recession could not make wage gains.
Management was becoming increasingly aware of the costs of poor occupational health and safety practices. Government was increasingly aware of the economic dimensions, seeing the need to improve working conditions and occupational health and safety practice to cut costs, increase efficiency and attract investment. Some of the early occupational health and safety acts may well have been part of attempts by economically weak states to attract capital (Pearse & Refshauge, 1987).
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By the early 1980s governments recognised that reducing compensation costs was top priority. Occupational health and safety legislation, aimed at reducing occupational injury and disease, was thus seem as a means of increasing the competitiveness of industry” (Carson & Hennenberg, 1988).
As a result of these and other influences, occupational health and
safety legislation in Australia underwent major changes in the 1980’s.
Legislation in all states and the Commonwealth changed from
prescription-based legislation to performance-based legislation based
on the U.K. model introduced in 1974 response to the Roben’s Report.
One of the basic tenants of this approach is that management systems
and compliance with regulations are complementary. An Australian
performance-based regulation is designed to allow the certainty of
performance and flexibility of approach. Three steps in hazard-based
regulations (hazard identification, risk assessment and risk control)
have been designed for integration into management systems.
Australian initiatives encourage management, motivation and
commitment to improve practice. It is unlikely, that any one
occupational health and safety management system will suit all
enterprises (Emmett, 1995).
Under prescriptive legislation, regulations specified the requirements
for compliance, both what needed to be done and how. Standards are
referenced as regulations, which were compulsory; non-compliance is
an offence.
Regulations under performance-based legislation generally expand on
the general duty of care and detail what needs to be done, but not how.
Codes of Practice are used to illustrate and give guidance on one
acceptable method of complying with the Act and regulations (Emmett,
1995).
Broad features of the old prescriptive approach are an emphasis on
setting compulsory standards, little flexibility, and responsibility for
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ensuring compliance resting with the inspector and, unfortunately, little
ownership within the workplace
Features of the performance-based approach are an emphasis on
providing a framework for workplace occupational health and safety
systems, the provision of advice by inspectorates, maximum flexibility
and workplace auditing (with worker participation) to provide checks
and balances. Most importantly, primary responsibility for compliance
resides within the workplace (Johnstone, 1997).
The Australian legislative system with respect to occupational health
and safety is a federal system. Each State or Territory is responsible
for regulating occupational health and safety within its own borders.
The Federal Government has responsibility for regulating the
occupational health and safety of its own employees. Under this
system, all bodies have developed what is essentially, a uniform
legislative approach. Differences do exist but these, in the main are
minor.
In 1981 the Federal Government established the National Occupational
Health and Safety Commission whose activities were overseen by a
tripartite board with representatives from government, industry and
unions. This Commission was charged with a number of
responsibilities including the responsibility of achieving a uniform
approach to occupational health and safety throughout Australia, and
promoting occupational health and safety education and research. The
Commission would regularly publish draft Regulations and Codes of
Practice which would act as the models upon which the States would
base their own legislation. Through the actions of successive
conservative governments in the 1990’s the role and influence of this
body has been progressively lessened and it now acts as little more
than a forum for the promotion of a uniform approach. Its ability to
produce model Regulations and Codes of Practice has been
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significantly reduced and it now has very little input into research and
education.
There are many aspects to the legislation that are important to
understand to address responsibilities with respects to occupational
health and safety in Queensland, Australia. The legislative
arrangements in Queensland are typical of those in other States of
Australia and form the focus of this Thesis as the Australian portion of
the research was undertaken in Queensland.
In Queensland, the Workplace Health and Safety Act (1995) is
supported by Regulations and Advisory Standards16. Regulations are
based around a codification of the common law duty of care. This
general duty is accompanied by a set of specific rules, which govern
how it is to be fulfilled. Employers have an obligation to take care of
themselves and to protect the health and safety of their employees and
others in their workplace or from workplace activities which could
adversely affect their health and safety.
The obligations of employers in Queensland are centred on the
requirement for them “to ensure the workplace health and safety of
each of the employer’s workers in the conduct of the employer’s
business or undertaking (Workplace Health and Safety Act 1995
s28[1])”.
2.3.2.1 Hazardous substances legislation
As noted above, the Australian legislative framework with respect to
occupational health and safety is a federal framework with the States
having the ability to act autonomously. However, the reality is that
there is a great deal of uniformity with respect to the requirements of
legislation from one State or Territory to another. This is particularly the
case with legislation regarding hazardous substances management.
This section of the Literature Review will therefore outline the 16 Advisory Standards in Queensland essentially play the role of Codes of Practice in other States.
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requirements for hazardous substances management in Queensland
where the study is based.
The Regulation dealing with hazardous substances in Queensland
(Workplace Health and Safety Regulation 1997 [Qld] Part 13) requires,
among other things that Material Safety Data Sheets must be available
for all hazardous substances must be kept “close enough to where the
substance is being used to and allow a worker who may be exposed to
the substance to refer to it easily (S103[2]). The Regulation also
contains requirements on suppliers, manufacturers, importers, and
others to ensure that Material Safety Data Sheets are available in the
workplace.
The principal requirements of the hazardous substance regulations are
centred on the requirement for employers’ to undertake risk
assessments and then base the controls in their workplace to deal with
the results of these assessments.
In particular,
(1) An employer or self-employed person must assess the risk to the health of the employer, self-employed person or a worker from a hazardous substance that is used, or is to be used at the workplace.
(2) The assessment must be done- (a) as soon as practicable after it is used; and (b) within 5 years of the last assessment; and (c) when any of the following happen at the workplace- (i) a work practice involving the substance is significantly changed (ii) health surveillance or monitoring shows control measures need to be reviewed; (iv) new or improved control measures are implemented (Workplace Health and Safety Regulation 1997[Qld] S105).
Details of the requirements of the risk assessment, and records of it,
are set out in the Regulation and further guidance in provided in the
Hazardous Substances Advisory Standard 2003. The emphasis is to
ensure that exposure to the hazardous substance is prevented.
Exposure in the Regulation is defined as:
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A person is “exposed” to a hazardous substance if the person absorbs, or is likely to absorb, the substance— a) by ingestion or inhalation, or b) through the skin or mucous membrane (Workplace Health and Safety Regulation 1997 [Qld] s87).
If a person is found to be exposed the employer must:
(a) prevent the exposure, or (b) if prevention is not practicable—reduce the exposure to as low a level as is practicable, but in any case the exposure must not be more than the relevant national exposure standard for the relevant period for the substance (Workplace Health and Safety Regulation 1997[Qld]s107[1]).
If the risk assessment shows that monitoring is required, the employer
must arrange for this to be undertaken and make the results available
to the worker concerned. Monitoring is defined as:
“monitoring” means regular checking, other than by biological monitoring— (a) a person’s risk form , or level of exposure to, a hazardous substance; and (b) the effectiveness of hazardous substance control measures at a person’s workplace (Workplace Health and Safety Regulation 1997[Qld]Schedule 9).
Similarly, the employer must arrange for health surveillance to be
undertaken if the risk assessment shows that a person has been
exposed to a hazardous substance and a variety of other tests are met.
These include, if the person is
exposed to a particular list of substances, or
as a result of the work, the worker is likely to suffer an
identifiable and detectable adverse health effect, or
as a result of the work, the worker is likely to suffer an
identifiable adverse health effect for which a valid biological
monitoring procedure is available.
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The health surveillance must be undertaken by or under the
supervision of a designated doctor who is
a doctor— (a) who is registered as a specialist registrant in the speciality of occupational medicine under the Medical Practitioners Registration Act 2001; or (b) who has satisfactorily completed a health surveillance training program supplied by the chief executive (Workplace Health and Safety Regulation 1997 [Qld] Schedule 9).
The specific health surveillance required is not specified but the
Workplace Health and Safety Regulation 1997 (Schedule 9) defines
health surveillance as:
the monitoring (including biological monitoring and medical assessment) of a person to identify changes in the person’s health because of exposure to a hazardous substance or lead.
There are no guidelines contained in the Regulation for the frequency
of health surveillance or the matters to be considered. An indication of
what is required is given in the details of what is required in a health
surveillance report. A health surveillance report must be prepared by
the designated doctor and provided to the employer, the worker and
the chief executive and this report must include information about:
(a) the effects on a person’s health related to the person’s exposure to a hazardous substance at a workplace; and
(b) the need (if any) for remedial action (Workplace Health and Safety Regulation 1997 [Qld]s109[8]).
The Regulation does not direct doctors to inform the Division of
Workplace Health and Safety of their findings, or require doctors to
direct what remedial action should be taken or, in this instance even to
recommend the type of remedial action needed. The Queensland
Division of Workplace Health and Safety (c.2002) notes that this
provision of the legislation gives rise to some confusion for doctors.
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The reason for this is that subordinate legislation can only apply to people mentioned in the Act of Parliament which applies (the Principal Act). For occupational health and safety in Queensland, the Principal Act is the Workplace Health and Safety Act (1995) and it does not contain any obligation which covers medical practitioners (except in their role as employers, self employed persons or workers). Hence the Regulation is written in a way that places the obligations on employers or workers (Division of Workplace Health and Safety [Qld] c2002., p5).
The employer is not required to notify the Division of Workplace Health
and Safety of the contents of the report but must keep a copy of the
report, any risk assessment which shows a significant degree of risk to
health, and any monitoring results for 30 years. These reports may be
inspected by a worker involved or an inspector from the Division of
Workplace Health and Safety.
The Regulation also stipulates that workers who may be exposed to a
hazardous substance are given induction and ongoing training about
the substance.
2.3.2.1.1 Lead
The regulation of lead (Workplace Health and Safety Regulation 1997
[Qld] Part 14) in Queensland is treated separately from the regulation
of other hazardous substance. However, the requirements are
generally the same as that required for other hazardous substances.
As stated above, the obligations of employers in Queensland are
centred on the requirement for them “to assess the risk to the health of
the employer, self-employed person or a worker from a lead process at
the workplace (Workplace Health and Safety Act 1995 s129)”. Where
this risk assessment shows a process includes a lead-risk job, the
employer must ensure that a number of controls are implemented and
arrange for atmospheric monitoring and health surveillance.
A “lead-risk job” is defined in the Workplace Health and Safety
Regulation 1997 (Schedule 9) as:
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a job in which – (a) a person may be exposed to lead; and (b) a person’s blood level does, or may reasonably be expected to equal or exceed – (i) for a female who is pregnant or breast feeding – 0.72 µmol/L 15µg/dL); and (ii) for a female with a reproductive capacity - 0.97 µmol/L (20µg/dL); and (iii) for anyone else – 1.45 µmol/L (30µg/dL).
As noted above, health surveillance required includes medical
assessment and biological monitoring and must be undertaken by a
designated doctor.
For workers 17 about to start work in a lead-risk job, this involves
surveillance:
Before the worker starts work; and
1 month after the worker starts work; and
further surveillance 3 months and 6 months after the worker
starts work (Workplace Health and Safety Regulation 1997,
Section 133[2]).
For workers who work in a lead-risk job health surveillance is required:
within 1 month after the risk assessment shows the job is a
lead-risk job; and
at any other time if requested by the designated doctor
(Workplace Health and Safety Regulation 1997 Section 133[3]).
The requirements for the health surveillance report are slightly different
from that for hazardous substances generally and require that, where
health surveillance is undertaken, a health surveillance report must be
17 The term “workers” in this context also includes the employer and self-employed persons where they may be exposed to lead.
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prepared and provided to the employer, the worker and the chief
executive18 and this report must include information about:
(c) the effects on a person’s health related to the person’s exposure to lead because of a lead-risk job; and
(d) the need (if any) for remedial action; and
(e) the type of remedial action needed (Workplace Health and Safety Regulation 1999 Section 133(11).
In addition, the Division of Workplace Health and Safety provides
doctors wishing to become part of the designated doctor program with
an information package that details the baseline health surveillance
data to be collected at the time of employment. This package also
includes information on the frequency of further monitoring required
determined by previous results (Division of Workplace Health and
Safety (Qld) c.2002)
In this instance the employer is required to notify the chief executive of
the results of the health surveillance (Workplace Health and Safety
Regulation 1997[Qld]s133[4][d]).
The frequency of further monitoring required is based on the National
Occupational Health and Safety Commission’s National Standard for
the Control of Inorganic Lead at Work [NOHSC:1012(1994)] which are:
(a) Once every six months if the most recent blood lead level is less than:
1.45µmol/L (30µg/dL)-for males and females not of reproductive capacity, 1.45µmol/L (30µg/dL)-for male of reproductive capacity;
(b) Once every three months if the most recent blood lead level is:
1.45 – 1.88 µmol/L (30-39µg/dL)- for males and females not of reproductive capacity, 1.45 – 1.88 µmol/L (30-39µg/dL)-for males of reproductive capacity, less than 0.48 µmol/L (10µg/dL)-for females of reproductive capacity; and
18 The term “chief executive” refers to the Head of the Department responsible for the administration of the legislation.
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(c) At least once every six weeks if the most recent blood lead level is at or above:
1.93µmol/L (40µg/dL)- for males and females not of reproductive capacity, 1.93µmol/L (40µg/dL)- for males of reproductive capacity, 0.48 µmol/L (10µg/dL)-for females of reproductive capacity (p. 17-18).
The Standard further stipulates:
Medical removal
If the results of biological monitoring reveal that the confirmed blood lead level is at or above:
2.41µmol/L (50µg/dL)- for males and females not of reproductive capacity, 2.41µmol/L (50µg/dL)- for males of reproductive capacity, 0.97 µmol/L (20µg/dL)-for females of reproductive capacity, 0.72µmol/L (15µg/dL)-for females who are pregnant or breast feeding (p18),
and
An employer shall ensure that the employee does not return to a lead-risk job until:
(a) the confirmed blood lead level is less than: 1.93µmol/L (40µg/dL)- for males and females not of reproductive capacity, 1.93µmol/L (40µg/dL)- for males of reproductive capacity, 0.48 µmol/L (10µg/dL)-for females of reproductive capacity, including, females who have ceased their pregnancy and are not breast-feeding; and (b) the employee is certified as fit to return to a lead-risk job by the authorised medical practitioner (p 19).
In summary, the identification of workers at risk of lead exposure
depends primarily on the risk assessment prepared by the employer.
Where an employer determines that a job may be a lead-risk job, the
employer has a number of obligations, including the arrangement of
health surveillance of any workers involved. Health surveillance,
including biological monitoring, must be undertaken by designated
doctors. Although designated doctors have very limited obligations
under the legislation, employers can only comply with their obligations
in conditions where lead risk jobs exist with the cooperation of the
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designated doctor. Thus, given the services that designated doctors
are required to perform and the advice that they are required to give, it
is essential that they have a good knowledge of the possible adverse
effects of exposure to lead and the requirements of the legislation.
2.3.2.1.2 Mercury
The regulation of mercury in Queensland falls under the general
requirements for hazardous substances outlined above.
The Regulation does not stipulate particular actions to be taken where,
if, as a result of biological monitoring which can form part of the health
surveillance, mercury is detected in the urine. However, in Australia,
the National Occupational Health and Safety Commission (NOHSC)
has established guidelines for health surveillance of a number of
substances including organic mercury.
In the absence of any State regulation on health surveillance for
particular substances, such as for inorganic mercury, in Queensland,
designated doctors usually refer to, and make recommendations based
on, the appropriate National Occupational Health and Safety
Commission Guideline. In this instance, the Guidelines for Health
Surveillance: Inorganic Mercury (NOHSC:7039, 1995) set the following
guidelines:
Baseline Level
Spot creatinine corrected urine for inorganic mercury to be conducted every 90 days. Where there is 50 µg inorganic mercury or more per gram of creatinine, a repeat spot creatinine corrected urine for inorganic mercury should be performed at the same time of the day.
Action Level
On confirmation of a level of 50 µg inorganic mercury or more per gram of creatinine, a medical examination with emphasis on the neurological, gastrointestinal, renal and dermatological systems should be performed.
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The employer should be informed when abnormal findings are detected so that control measures can be checked. The employee should be informed of the results of the health surveillance.
Removal Level
Removal from mercury work should be considered if clinical signs of mercury poisoning are present or if the level of inorganic mercury in urine is greater than 100 µg per gram of creatinine.
The person should be investigate every 30 days until the level falls below 50 µg inorganic mercury per gram of creatinine on two successive occasions. The test may be performed more frequently in individual circumstances.
The 90 day protocol may then be resumed. (National Occupational Health and Safety Commission 1995b).
2.3.3 Comparison of Australian and Korean legislative approaches to occupational health and safety
A summary of the essential differences in the Australia and Korean
occupational health and safety legislation is given in Table 2.9.
Table 2.9: Description of state of OHS development in Australia and Korea
AUSTRALIA KOREA Type of OHS legislative framework Robens-style of self-regulation was introduced across the country in the 1980s. Performance-based legislation. Each of the eight States and Territories and the Commonwealth jurisdiction have their own legislation, but there is reference to national standards develop[ed by the National Occupational Health and Safety Commission (NOHSC) and, for some technical standards, Standards Australia.
Rules-based (prescription-based) regulation, not Robens-style of self-regulation (Industrial Safety and Health Act), which emphasised employer responsibility, was introduced across the country in 1982. The Act is the National standard.
Implementation policy The mission of the National Occupational Health and Safety Commission is “to lead and coordinate national efforts to prevent workplace death, injury and disease in Australia”. Enforcement is by State government (and Commonwealth for its employees). The Commonwealth Government, eight State and Territory Governments, the Australian Chamber of Commerce and Industry and the Australian Council of Trade Unions have recently committed to a ten-year plan: National OHS Strategy 2002-2012.
The Industrial Safety and Health Bureau, which replaced the Industrial Safety Bureau in 1998, in the Ministry of Labor enforces relevant laws and regulations and provides guidelines for controlling work-related diseases (Ministry of Labor, c 1999).
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AUSTRALIA KOREA Stated national OHS priorities From the above-mentioned strategy priorities are: Reduce high incidence/severity risks Improve capacity of business operators and workers to manage OHS effetely. Prevent occupational disease more effectively. Eliminate hazards at the design stage. Strengthen the capacity of government to influence OHS outcomes.
Stated national OHS priorities are: Prevention of traditional occupational diseases and work-related diseases. Reduction of chemical hazards. Building of surveillance system focused on work-related diseases. More attention is paid to work-related musculoskeletal disease and cardiovascular disease, as well as strengthening the measures to prevent against work-related disease and occupational accidents in small scaled enterprises with less than 50 workers.
OHS targets and performance at a national level From above- motioned strategy: Reduce fatalities by 20% by 2012 and by 10% by 2007 Reduce injury by 40% by 2012 and by 20% by 2007. Rates are already declining. Most recent figures are: For fatalities (working only, not commuting, including work –road) over 1989-1992 there was an average of 5.5 per 100,000 per year. New workers’ compensation claims for injuries over 5 days, in 1999-2000 was 20.58 per 1,000 workers.
OHS targets are decreasing traditional occupational /work-related diseases and industrial accidents. The most important indicators at a national level are the industrial accident rate and number of occupational or work-related disease cases, including work-related cardiovascular disease such as Karoshi. By these indicators the situation is worsening. The most recent data are: From 2000 to 2001 the accident rate involving >3 days hospitalisation increased from 0.73% to 0.77% of the workforce. From 2000 to 2001 the numbers of occupational or work-related disease increased from 2,938 to 4,396 in 2001 (note : the classification methods changed; however, the increasing trend is clear).
Description of current state of industry practice The last major review of OHS nationally was industry Commission 1995, Work, Safety and Health Inquiry into occupational health and safety, report no. 47, volumes 1 and 2, Ausinfo, Canbera. This report recognised that many employers see occupational health as an investment, not a cost, and should not be restricted by regulations. However, stricter enforcement of legislation was recommended for less enlightened employers. Small to medium sized enterprise was identified as a major priority. Simplifying and standardising OHS regulation was recommended (nut not taken up). Broadening partnerships for OHS both within government and outside was initiated.
It is recognised that employers tend to see occupational health as a cost, not an investment. By rule-based many employers aim to meet the minimum standards prescribed by regulation, but no more than that. They have become very passive in protecting the workers’ health. A scheme by which occupational health support services for small- medium enterprises are funded from the Occupational Injury Prevention Fund (5% of the Occupational Injury Compensation Insurance Premium) has been developed.
Current contribution by unions to occupational health development Considerably weakened by decline in union membership, reduction in influence of the National Occupational Health and Safety Commission and abandonment of tripartite structures buy some State Governments.
There has been considerable contribution by strong unions. National trade union centres and prominent industry-level trade union organisations are emphasising employer responsibilities and asking for more compensation on work-related musculoskeletal and cardiovascular disease. Thus, unions’ stance is compensation-orientated, but not prevention or promotion-oriented.
Workforce development Australia has shown international leadership on definition of competencies in OHS (National Occupational Health and Safety Commission, 1998) Professional bodies for occupational medicine, occupational health nurses, hygienists, safety practitioners and ergonomists have defined competencies and manage professional certification. There are recently established links between professional bodies and National Occupational Health and Safety Commission. The recent loss of the national occupational health and safety academic institute may have a negative effect professional development.
Professional bodies for occupational medicine, occupational health nurses, hygienists, safety practitioners and ergonomists have defined competencies and manage certification.
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AUSTRALIA KOREA References (Ellis, 2001; National Occupational Health and Safety Commission)
(Lee, 1998b; Park & Kim, 1998; Kim, Park et al., 1999; Park & Kim, 1999)
2.4 Occupational health and safety management systems
2.4.1 Introduction
This section aims to provide an overview of the occupational health
and safety management system phenomenon; it starts by looking at
the definitions, and characteristics, of occupational health and safety
management systems before reviewing the historical origins of the
occupational health and safety management system strategy. Specific
occupational health and safety management system structures are
investigated and the literature on the effectiveness of occupational
health and safety management systems is reviewed.
The European Agency for Safety and Health at Work (2001) discussed
the advantage of strong occupational health and safety management
systems as being that bigger companies reduced their numbers of
work accidents and, through that, the working time lost. Further,
occupational health and safety management systems strengthened the
employees’ motivation, e.g. by giving them additional competencies.
Besides that, occupational health and safety management systems
increased the employees’ identification with their company.
One of the advantages to an occupational health and safety
management systems’ approach is resolution of the common criticism
that occupational health and safety is rarely integrated into business
systems but rather is typically a stand alone adjunct in most
companies.
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Additional values realised through the use of occupational health and
safety management systems include (European Agency for Safety and
Health at Work, 2001):
• alignment of occupational health and safety objectives with business objectives;
• integration of occupational health and safety programs/systems into business systems;
• establishment of a logical framework upon which to establish an OHS program;
• establishment of a universal set of more effectively communicated, policies, procedures, programs, and goals;
• applicability to, and inclusive of cultural and country differences;
• establishment of a continuous improvement framework; and
• provision of an auditable baseline for performance worldwide.
Some would argue that there are an equal number of disadvantages
also. Those most commonly cited include no need for change from
present approaches and practices, social and legal barriers
internationally that cannot be overcome by a standardized approach,
bureaucracy and cost (Gallagher, 1997).
There are few definitions of occupational health and safety
management systems available in the literature. The following are
some of the definitions which have been found. Bottomley (1999) and
Winder, Gardner, et al. (2001) provide reasonably simple definitions of
occupational health and safety management systems which
concentrate on the documentation and therefore verifiability of the
system:
Broadly speaking, an OHSMS is a planned, documented and verifiable method of managing workplace hazards and the risks associated with them (Bottomley, 1999).
and
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An OHSMS can be simple or complex, and it has recognisable models. However, it must be documented and formalised rather than haphazard and ad hoc (Winder, Gardner, et al., 2001.)
Gallagher’s definition concentrates on the outcomes to be achieved by
the occupational health and safety management system and some of
the elements which should be included within it. She also raises the
importance of integrating the occupational health and safety
management system with other management systems in the
workplace.
(An occupational health and safety management system is) a combination of the planing and review, the management organizational arrangements, the consultative arrangements, and the specific program elements that work together in an intergraded way to improve health and safety performance. ……. They differ from older methods in several ways. First, like the Robens’ reforms, they make those in the workplace more responsible for occupational health and safety (OHS). But, unlike the Robens’ reforms, this responsibility is discharged through an integrated management system rather than ad hoc structure and prescriptions (Gallagher, 2000:1).
As with the previous definition, AS/NZS 4804:2001 (Standards
Australia/Standards New Zealand 2001) stresses the importance of
integration with the overall management system of an organisation but
also includes the elements which should form part of the system:
That part of the overall management system which includes organizational structure, planning activities, responsibilities, practices, procedures. Processes and resources for developing, implementing, achieving, reviewing and maintaining the OHS policy, and so managing the risks associated with the business of the organisation.
There is a similarity in all of these definitions which is probably best
brought together in the definition provided in AS/NZS 4804:2001,
especially if it is recognised that this standard is used in conjunction
with AS/NZS 4801:2001 which provides a framework for an auditing
and certification processes. This brings into play the element which is
missing from the Standards Australia definition, that of the importance
of being able to verify the systems in place.
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The similarity of concepts is important in considering ways in which
legislation and occupational health and safety management systems
can productively interact to achieve better health and safety
performance. The difference between an outcome-based general duty
of care and a process-based organisational mechanism, an
occupational health and safety management system, needs to be kept
in mind.
Although both Gallagher (1997) and Winder, Gardner, et al. (2001)
also state that any system for dealing with workplace risks can be
called an occupational health and safety management system, there
are obvious problems with considering some of the more simplistic and
reactive systems to be found in many organisations as being proper
safety management systems. The primary aims of an occupational
health and safety management system should, therefore, be to:
• Identify and manage occupational health and safety risks in the workplace in a “structured” way;
• Promote a cycle of continuous improvement;
• Specify criteria by which an occupational health and safety management can be audited (Winder, Gardner, et al., 2001).
Occupational health and safety management systems are part of the
state of knowledge about how to manage occupational health and
safety and may be considered by a court in the same way that other
industry guidance and information is considered.
2.4.2 Components of an occupational health and safety management system
Occupational health and safety management systems include a
combination of management organisational arrangements including
planning and review, consultative arrangements, and the specific
program elements including hazard identification, risk assessment and
control, contractor health and safety, information and record keeping,
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and training. There are similarities in the structure of an occupational
health and safety management system, the framework of obligations
required by occupational health and safety legislation, and the
recommended systems that allow compliance. However it is critical to
understand that an occupational health and safety management
system is one means of meeting the obligations of occupational health
and safety legislation but is not a substitute for them.
Owen (1996) outlines a series of factors which can lead to good
occupational health and safety practice in an organisation, and these
include, by implication, the development of a occupational health and
safety management system.
• A positive workplace OHS culture actively fostered by senior management (this is strongly influenced by the general community OHS culture).
• Gearing management systems to the implementation and maintenance of a positive workplace OHS culture.
• Purchase, operation and maintenance of hardware in accordance with the requirements of a safe and healthy workplace.
Gardner (2001) outlines 4 general requirements for an occupational
health and safety management system:
• System objectives (for occupational health and safety management systems these may be ethical, economic, legal and organisational goals; not all systems need have the same objectives)
• Specific of system elements and their inter-relationship; not all systems need have the same elements.
• Determining the relationship of the occupational health and safety management system to other systems (including the general management system, and the regulatory systems but also technology and work organisation)
• Requirements for system maintenance (which may be internal, linked to a review phase, or external, linked for example to industry policies that support OHS best practice systems maintenance may vary between systems).
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There is a high level of agreement about the essential components of
an occupational health and safety management system by Winder,
Gardner, et al., (2001) and Gallagher (1997) Table 2.10).
Table 2.10: Essential elements of an occupational health and safety management system
Elements of an Occupational Health and Safety Management System Organisation, responsibility, accountability Organisation, responsibility, accountability Senior management commitment and active participation; Line management/supervisor involvement; Specialist personnel; Management accountability; Performance measurement; Management systems (starting with the OHS Policy).
Senior manager/involvements Line manager/supervisor duties Management accountability and performance measurement Company OHS policy
Consultative arrangements Consultative arrangements OHS Committee; Worker – management participation in workplace risk issues; Issue resolution procedures
Health and safety representatives-a system resources Issue resolution-HSR/ employee and employer representatives Joint OHS committees Broad employee participation
Specific programs. Specific program elements Systems for risk management, including workplace critical risks; OHS information and promotion; Health and safety rules and procedures; Assessment of training needs and a training program; Workplace assessments and inspections; Systems for first aid and medical surveillance; Emergency response; Procedures for purchasing, contract review, contractor management and so on; Incident reporting and Investigation; Systems for monitoring and review; Record keeping systems for risk management and incident investigation.
Health and safety rules and procedures Training program Workplace inspections Incident reporting and investigation Statement of principles for hazard prevention and control Data collection and analysis/record keeping OHS promotion and information provision Purchasing and design Emergency procedures Medical procedures Monitoring and evaluation Dealing with specific hazards and work organisation issues
(Winder, Gardner et al., 2001) (Gallagher, 1997)
The WorkCover Authority of New South Wales (1995) has outlined a
five-point approach to implement effective occupational health and
safety management systems:
1. Develop an OHS policy and related programs
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2. Set up a consultation mechanism with employees
3. Establish a hazard identification and workplace assessment process
4. Develop and implement risk control
5. Promote, maintain and improve these strategies (WorkCover, 1995)
Waring (1996) details a far more exhaustive process involving an
assessment of both the internal and external context because of the
profound effects that these can have on occupational health and safety
management systems. He discusses the following characteristics of an
occupational health and safety management system:
Regardless of how they are connected, it is generally accepted that any well-designed management system should possess, not necessarily in order of importance:
• a systematic framework which connects all components;
• a clear policy, strategy and objectives;
• clear responsibilities, accountabilities and authority of individuals;
• adequate means for organizing, planning, resourcing and decision-making;
• adequate means of implementing plans and decisions;
• a coherent and adequate set of measures of performance;
• adequate means for monitoring, assessing, auditing and reviewing both the quality of the system itself and how it functions;
• adequate numbers and allocation of competent well-led people;
• flow of adequate information to all those who require it;
• adequate intelligence about the inner and outer contexts of the organization;
• compatibility, if not integration, with other management systems in the organization (Waring, 1996: 61-62).
Aside from the general principles outlined above, there are a number of
existing occupational health and safety management systems and the
characteristics of two of these, the ILO Guidelines for occupational
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health and safety management systems and the approaches taken in
Australia with specific reference to AS/NZS 4804:2001, are discussed
in Section 2.4.4 Specific occupational health and safety system models
later in this Chapter.
2.4.3 Historical review of occupational health and safety management systems
The era of Fordism, characterised by stable industrial facilities and long
term employment which started early in the last century and continued
into the 1980’s has disappeared. Instability and lack of continuity are
now increasingly typical of enterprises. While some traditional
occupational safety problems have now largely disappeared, many
new technologies and the materials used are potentially more
dangerous than those of the past. The scale of production and
distribution has increased immensely and a single error can now result
in disastrous results. The scrutiny of the performance of organisations
has also increased, especially when the result of errors can have
environmental or public health impacts (Health and Safety Executive,
1981).
High technology demands high technical competence in controlling
risk, but even the highest technical competence will not, on its own,
ensure a consistently safe place of work.
Occupational health and safety management systems, which are seen
as a way of responding to the demands raised above, are not new and
many larger organisations had good procedures in place from the
1930's onwards. But It is argued (Sweeny, 1992) that the mid-1980s
saw a resurgence of interest in a systematic approach to health and
safety management, stimulated by two factors. First, the Bhopal
disaster was a powerful incentive for the process industries to ensure
the operation of effective health and safety management systems. A
second factor influencing the adoption of health and safety
management systems across industry was the renewed focus on
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innovative management practices aimed at transforming business
performance.
Following the Bhopal disaster, many enterprises in the high risk
process industries extended the focus of health and safety activity
beyond the traditional emphasis on process technology and technical
safeguards towards management practices, procedures and methods,
while attention was directed at industry level to models for system
development and performance measurement (Sweeny, 1992).
The mid-1980s also saw the appearance of health and safety
management systems beyond the process industries. In Australia,
manuals on health and safety management systems were published by
consultancy companies, employer organisations and governments
(Construction Industry Development Association, 1993; Department of
Labour [Victoria], 1988; WorkCover [South Australia], 1989). However,
while the 'systems' terminology in these manuals was new, the system
elements were consistent with the health and safety programs of
previous years (Gallagher, 1997).
Whilst an occupational health and safety management systems’
approach hasn't been equivocally linked with improved safety
performance, the lack of a systems-based approach usually results in a
reactive response to occupational health and safety issues and a
reluctance to concentrate on positive activities. This is reinforced by
the fact that, unless the organisation is an extremely poor performer,
most workgroups will have only a small number of serious accidents
during a working lifetime (Bennett, 2002). It is therefore possible to put-
off such reforms.
2.4.4 Specific occupational health and safety system models
As occupational health and safety management systems have become
more numerous and widespread, there has been a growing interest in
upgrading existing guidelines and codes of practice on how to organise
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occupational health and safety management systems, into formal
standards. The example for this was set in 1986 with the publication of
ISO 9000 standard on product quality. A suggested ISO 20000
standard for occupational health and safety management systems,
along the lines of ISO 14000 for environmental management systems,
was rejected in 1977. However, national standards have been issued
in countries such as the UK, Spain, the Netherlands and Australia/New
Zealand, and other countries like Norway, Jamaica and Ireland are
considering it. The international debate also continues. The
International Labour Office has recently issued guidelines on
Occupational Health and Safety Management System (International
Labour Office, 2001).
There is concern in the International Occupational Hygienists
Association that the present situation, where national, provincial/state,
industry and consultancy developed occupational health and safety
management system standards and guidance documents are being
developed in many different parts of the world, is causing confusion
and misunderstanding. Employers are often faced with competing
systems, but are being denied the opportunity to have their
occupational health and safety performance verified to an
internationally recognised standard by an accredited conformance-
assessment process (International Occupational Hygienists
Association, 1998).
The Australian experience leading to the development of AS/NZS
4804:2001 (Standards Australia/Standards New Zealand 2001b), the
now widely accepted standard for occupational health and safety
management systems in Australia, and the ILO Guidelines for
Occupational Safety and Health Management Systems (International
Labour Office 2001), which is fast being considered as the international
benchmark standard for occupational health and safety management
systems given the slow pace of development of an International
Standards Organisation standard, are discussed below.
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2.4.4.1 Australian Occupational Health and Safety Management Systems
In Australia, the promotion of occupational health and safety
management systems by regulators had modest beginning with the
introduction of self-audit tools in Queensland and Victoria in the mid-
1990s. These tools were designed so that employers could; assess
the scope and effectiveness of their occupational health and safety
policies and practices, establish benchmarks plan improvements and
gain recognition for the standards achieved (Viner, Robinson, Jarman
Pty. Ltd. and Victorian Institute of Occupational Safety and Health,
1989)
A dominant model for auditing occupational health and safety
management systems, which is promoted by the Victoria Workcover
Authority, is called SafetyMAP and this is an audit checklist for a
general safety management system which is designed to be
compatible with quality management systems.
The key elements of a occupational health and safety management
system as defined by the New South Wales Government are:
• Management responsibility
• Subcontracting and purchasing
• Process control
• Inspection and testing
• Control of OHS issues
• Corrective action
• Handing, storage, packaging and delivery of hazardous substances
• Training
• OHS records
• Design
• Internal OHS reviews
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Other optional elements covered include;
• Documentation
• Client supplied product
• Product identification and traceability
• Inspection, measuring and test equipment
• Inspection and test status
• Servicing
• Statistical techniques
(Capital project procurement manual, 2nd edition, NSW Government, Sydney (Undated)
SafetyMap (Victorian government authority, 1990s) is not so much a
set of standards as an auditing tool used to assess an organisation's
systems for compliance with the Victorian regulations. It is quite
prescriptive and lacks flexibility in common to many audit system.
Other occupational health and safety management systems or
occupational health and safety management systems audit criteria
available through regulatory bodies in Australia include;
TriSafe Management Systems Audit (Department of
Employment, Training and Industrial Relations, Division of
Workplace Health and Safety, Queensland);
SafetyMap: Auditing Health and Safety Management Systems
(Victorian WorkCover Authority)
Performance Standards for the Safety Achiever Bonus Scheme
(WorkCover Corporation of South Australia);
WorkSafe Plan (WorkSafe Western Australia);
Capital Works Investment: OHS & R Management Systems
(Capital project procurement manual, WorkCover Authority,
New South Wales);
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ComCare SRC Risk Management Model (Commonwealth).
Standards Australia released in 1997 a Joint Australian & New Zealand
Standard AS/NZS 4804: Occupational Health and Safety Management
Systems – General Guidelines on Principles, Systems and Supporting
Techniques. The second edition of the standard was released in 2001.
AS/NZS 4804:2001 (Standards Australia/Standards New Zealand
2001b) describes a systematic management approach that can assist
in both meeting legal requirements and sustaining improvement in
occupational health and safety performance. The underlying
philosophy of this standard is one of continual improvement based on a
repeating cycle of planning the system, implementing the plans,
measuring the implementation and reviewing and improving the system
based on the results of the evaluation.
Figure 2. 2: OHS Management system model (After: Standards Australia/Standards New Zealand 2001: vi)
An associated standard is AS/NZS 4801:2001: Occupational health
and safety management systems – Specification with guidance for use
(Standards Australia/Standards New Zealand 2001a). This document
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sets out the requirements to be used for auditing and certification of
occupational health and safety management systems.
The Australian/New Zealand Standard AS/NZS 4804:2001 defines the
principle elements of an occupational health and safety management
system as:
• Commitment and policy
• Planning
• Implementation
• Measurement and evaluation
• Review and improvement
AS/NZS 4804:2001 and AS/NZS 4801:2001 have been written to apply
to all types and size of organisations and to be generic enough to
accommodate diverse geographical, cultural and social conditions, as
well as the multiplicity of occupational health and safety legal
jurisdictions. Thus two organisations carrying out similar activities but
having different occupational health and safety management systems
and performances may both conform to the requirements established
in AS/NZS 4801:2001. It is also likely that the International Standards
Organisation (ISO) will consider the Australian experience with AS/NZS
4804:2001 when developing an international standard for occupational
health and safety management systems in the future.
Indeed, in 1999 a consortium of (mainly European) standards boards and certification organisations issued an OH&S Assessment Series (OHSAS 18001) though a consortium with the British Standards Institution. This draft "management system" has a similar structure to AS 4801 and AS/NZS 4804 (which were used in development). While the ISO has recently called for expressions of interest about developing an International standard for OHSMS, it has not announced whether it will use OHSAS 18001 as the basis for it. However, organisations in some countries in Europe and Asia are developing OHSMS to the OHSAS 18001 system, which is becoming the de facto international standard (Winder, Gardner, et al., 2001).
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2.4.4.2 ILO Guidelines on occupational safety and health management
Many occupational health and safety management systems are based
on either ISO 9000 or ISO 14000 series standards in order to exploit
integration opportunities. Key events within the International Standards
Organisation include:
the publication of a quality-assurance management system (ISO 9000)
in 1986;
an environmental management system (ISO 14000) published in 1996;
and,
the decision not to develop an ISO occupational health and safety
management system standard in 1997.
Nation-state, professional-society, and industry activities in the early to
mid-1990s included the development and publication of a range of
occupational health and safety management systems. (Table 2.11)
Table 2.11: Examples of occupational health and safety management systems
Country Types of OHSMS
Australia SafetyMap, TriSafe, ComCare self audit program,
United States – OSHA Voluntary Protection Programs
British Standards Institute BS 8800
UK - Chemical Industries’ Association Responsible Care
US - Chemical Manufacturers’ Association
Responsible Care
American Industrial Hygiene Association Occupational Health and Safety Management Systems Guidance Document
The International Labour Office has identified that there are publicly
available 31 occupational health and safety management system
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models, standards, guidance documents, and codes of practice
(International Labor Office, 1996).
The ILO Guidelines on occupational safety and health management
are designed to take into account those occupational safety and health
management-related programmes that are already in use
internationally. These include Responsible Care, Private Voluntary
Initiatives, Corporate Social Responsibility, Good practice in
occupational safety and health, Codes of conduct, and ISO
International Standards on Quality and Environment. In addition,
international reality requires that the Guidelines address some issues,
which require special consideration. These issues are, in particular,
different means and tools used with regard to:
• the implementation of adequate and appropriate OSH management systems for small and medium-sized organizations;
• the professional contribution of insurance companies, labour inspection services as well as occupational safety, health and other services to the establishment and effective implementation and review of OSH-MS in organizations;
• the very complex problem of motivation of organization management, e.g. by means of insurance rate discounts, extended inspection intervals or other incentive schemes;
• the publication and advertisement of the existence of OSH management systems or good OSH practice in an organization, in particular its specific promotion and recognition by means of certification, semi-certification or other practices (International Labor Office, 2001).
The ILO Guidelines on occupational safety and health management
systems (International Labour Office, 2001) refer to both the
establishment of an appropriate and adequate national framework and
the different fundamental elements that should be considered in an
appropriate way in an occupational health and safety management
system of an organisation.
The ILO Guidelines differ from those already discussed in that they
include the role of government in the process and are not just restricted
to the organisational elements discussed to date. The national
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framework for occupational health and safety management systems
should comprise the following:
• the nomination of a national competent authority, and the formulation, implementation and periodical review of a coherent national policy regarding OSH management;
• the elaboration of general national guidelines or framework documents, in line with the ILO Guidelines and other internationally available information and in accordance with national law and practice;
• the adaptation, by recognized institutions, of the national guidelines to tailored OSH management systems which meet the specific requirements and needs of individual organizations, groups of organizations, branches, etc. and correspond to their specialities, in particular, with regard to their size, nature of activities and other special conditions (International Labor Office, 2001).
2.4.5 Occupational health and safety management systems research
2.4.5.1 Industries and workplaces implementing occupational health and safety management systems
According to recent occupational health and safety management
system studies by researchers such as (Bottomley, 1999; Gunningham
& Johnstone, 1999; Winder, Gardner et al., 2001; Frick, Per Langaa et
al., 2002; Redinger, Levine et al., 2002; Gallagher, 1997) promoting
continuous improvement in occupational health and safety should be a
major task of every workplace’s activities in the 21st century.
There are little survey data to identify particular industry sectors that are
greater users of occupational health and safety management systems
than others. Similarly, there is mainly anecdotal evidence that smaller
organisations (Gallagher, 1997) are less likely to have implemented an
occupational health and safety management systems than larger
organisations. There are examples of a wide variety of industry sectors
that use occupational health and safety management systems and
some examples of smaller organisations that have developed an
occupational health and safety management system.
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These suggest that industry sector and size may not be critical
dimensions when looking at the use and role of occupational health
and safety management systems. This is not to say that these
dimensions are not important in the shape that an occupational health
and safety management system might take, but that factors like the
level of risk may be much more important (Bottomley, 1996).
2.4.5.2 Motivation
The growing interest in, and promotion of, occupational health and
safety management systems over the past decade suggests that
health and safety management systems represent a key new
prevention strategy. However, there is limited evidence about the
ability of occupational health and safety management systems to
prevent major incidents involving death, serious injury, ill health or
disease and damage to property and the environment.
Gallagher (1994) and (Brazier & Waite, 2003) find 2 major factors and
a number of subsidiary factors motivate both small manufacturing
enterprises and large organisations to initiate health and safety
improvements.
The major finding is that there are two factors that motivate both small
medium-sized enterprise and large organisations to initiate health and
safety improvement. They are fear of loss of credibility and perceived
duty to comply with health and safety regulations. Other factors
included the avoidance of costs of injury and ill health, the wish to
improve staff morale and productivity and integration of occupational
health and safety with quality systems (Brazier & Waite, 2003).
The primary rationale for ongoing development of health and safety
management systems is the achievement of safe and healthy
workplaces. The principle criterion for success is a reduction in the
incidence and severity of work-related injury and disease. Descriptive
and case study accounts attest to the success of particular firms in
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improving health and safety performance following concerted effort to
improve health and safety management (Pitblado, Williams et al., 1990;
WorkSafe, 1992; Lauriski & Guymon, 1989).
2.4.5.3 Impact on performance
Despite the attention given to occupational health and safety
management systems there has been relatively little attention given to
the measurement of occupational health and safety management
systems effectiveness. First, there has been little, if any scholarly
examination of the validity and reliability of instruments used in
assessing different occupational health and safety management
systems. Most studies rely on the impact on injury and/or accident
rates and these are widely accepted as being poor indicators of health
and safety performance because they are affected by a large range of
social and economic factors as well as the management of health and
safety in the workplace. Second no universal assessment instruments
have been developed for occupational health and safety management
systems (Quinlan 1993).
Waring (1996: 146-168) details four kinds of measure of safety
performance:
reactive and proactive measures
quantitative and qualitative measures.
He notes that accident data is a reactive measure that is not an
accurate and complete measure of safety performance (Waring, 1996:
150). This claim receives substantial support from other authors who
note that accident data is:
• a reactive instrument that measures failure rather than success;
• affected by social and economic factors outside workplace
control;
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• not a reliable measure of safety performance;
• affected by the latent nature of many occupational injuries and
diseases (Pybus, 1996; Reason, 1997; Tarrants, 1980)
However, in spite of the lack of a universal assessment instrument for
occupational health and safety management systems, evidence from
around the world suggest that occupational health and safety should be
managed in a planned and systematic manner, and that the greater the
degree of integration of occupational health and safety into the overall
management process, the greater the opportunities to bring about long-
term improvements. Michael Quinlan reports that surveys in Sweden,
Norway and Denmark have clearly indicated greater occupational
health and safety awareness with clearer lines of responsibility within
management. The study also indicated improved risk assessments,
quality management processes, occupational health and safety
documentation, and clearer defined strategic planning promoted
greater occupational health and safety awareness (Quinlan & Bohle,
1993).
There is some evidence to suggest that the application of effective
management systems in the building and construction industry can
lead to a reduced incidence of injury and disease (Lowery, Moore et al.,
1988; Davies and Tomasin 1996; Lowery, Moore et al., 1998; Synnett,
1992)
Research by Gallagher (1994) into a wide variety of Australian
industries found a positive relationship between more developed
occupational health and safety management systems and the
reduction of worker’s compensation claims
Investigation of the links between health and safety management effort
and injury performance also connects a group of studies, which
analyses health and safety program effectiveness. The studies have
explored organisational and health and safety system/program
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characteristics, sometimes referred to as the safety climate (Glennon,
1982).
The 1970s saw the first comparative studies, where firms with high and
low injury frequency rates were studied in an attempt to isolate
significant health and safety practices. Simonds and Shafai-Sahral
studied eleven pairs of firms in the manufacturing sector in Michigan,
matched for industry and size by differing in work injury frequency rates
by a ratio of 3 to 1 (Simonds & Shafai-Sahral, 1978). The study
involved structured interviews with company management, analysis of
relevant company records and a walk-through survey of work areas.
The primary factor found to be related to lower injury frequency rates
was greater senior management involvement in health and safety
activity, with particular reference to conduct of workplace
audits/inspections, formal review and analysis of safety plan outcomes
and the practice of featuring safety issues on the agenda of company
board meetings.
Cohen and Cleveland (1983) reported on a National Institute of
Occupational Safety and Health project involving the study of five
companies with exemplary health and safety performance. While each
of the companies had distinctive health and safety programs, some
common factors were found:
firstly, they accorded real priority to health and safety in
corporate policy and action,
secondly, they were found to include health and safety as an
integral, not an isolated, part of the organisational decision-
making process; and
thirdly, they shared general characteristics of successful health
and safety programs. That is, they set goals, assigned
responsibilities, provided adequate resources, identified and
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dealt with hazards, motivated and involved employees, and
evaluated health and safety performance.
The Victorian Institute of Occupational Safety and Health attempted to
find the factors contributing to high levels of health and safety
performance. The study investigated 16 good performers within poorly
performing industries, identified from accident compensation data.
Based on structured interviews with managers, supervisors, health and
safety representatives and employees at each location, the study
examined the interaction of health and safety program efforts with
broader organisational characteristics and health and safety
performance outcomes (Viner, Robinson, Jarman Pty. Ltd. and
Victorian Institute of Occupational Safety and Health, 1989). Six key
characteristics of an effective health and safety program were
identified:
health and safety management emerged as a key outcome, with a focus on responsibilities and accountability of management at all levels. Other key findings were:
frank and open communication practices,
employee consultation,
health and safety knowledge and equipment,
prevention effort, as indicated by attention to hazard control hierarchies, and
planned identification, control and, monitoring processes (Viner, Robinson, Jarman Pty. Ltd. and Victorian Institute of Occupational Safety and Health, 1989).
Another study performed by (Gallagher, 1992) found the health and
safety management system characteristics in better and poorer
performing enterprises, as measured by the compensation claims
incidence rates. The study findings suggested the better performers
were more likely to have health and safety management systems in
place. A very different picture emerged in relation to the poorer
performers, where there were few links between system elements, and
an absence of correlations involving key system features such as
senior management involvement and system integration. And
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Gallagher postulates further that the linkages between consultative
arrangements and broader health and safety system elements in the
better performing enterprise indicated health and safety consultative
arrangements might contribute to an effective health and safety
management system.
There are few studies providing compelling evidence that a
management system with a strong employee participation emphasis
will yield positive results. One study that does reach this conclusion is
the Canadian case study of Painter and Smith (1986) that followed the
development and operation of a participatory safety and hazard
management program over a period of four years in six camps of a
logging company. All aspects of the program revolved around
employee involvement. From 1982 to 1985, the company experienced
a 75 percent decrease in accident frequency and a 62 percent
decrease in compensation claims costs. Nevertheless, the authors
acknowledge the difficulty in measuring the degree of impact of the
program on the results observed. They maintain that the belief of
company managers and employees that a cause-effect relationship
exists is, in itself, an important feature of the program’s acceptance and
success (Painter & Smith, 1986).
An Australian study by Bottomley (1996) of around 100 significant
incidents and a 10 percent sample of prohibition notices found that
organisational factors were more likely to explain these failures, or
potential failures, than individual factors or design/engineering factors.
The study highlighted the role of an effective occupational health and
safety management system in improving performance and the need for
very specific risk controls to be applied within the system.
In summary, there are a series of studies which have shown an
association between improved injury performance and the presence of
an occupational health and safety management system. Some studies
have identified particular characteristics of occupational health and
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safety management systems which have been related to these
outcomes. However, there have not been any studies which have
compared different systems and all of the studies have equated health
and safety performance with injury data despite the recognised
unreliability of this data in most text books on occupational health and
safety.
Organisations devote considerable resources to protecting worker
safety and ensuring healthy workplaces. For both business and
financial reasons, many go beyond the minimum requirements set by
occupational health and safety laws. Organisations develop
occupational health and safety management systems within the
context of:
• The general growth of concern from all interested parties about OHS matters.
• Changes to legislation.
• Other measures to foster sustained OHS improvement.
An Occupational Health and Safety Management System provides a framework for managing OHS responsibilities so they become more efficient and more integrated into overall business operations. Also they are based on standards, which specify a process of achieving continuously improved OHS performance and complying with legislation.
There are many reasons why organizations implement an OHSMS including legal imperatives, ethical concerns, industrial relations considerations and to improve financial performance. Implementation of an effective OHSMS should, however, primarily lead to a reduction of workplace illness and injury, minimizing the costs associated with workplace accidents. OHSMS are also used by some organizations to demonstrate, internally and in some cases externally (via self-declaration or certification/registration as appropriate), that they are systematically controlling the risks to all persons affected by the organization’s activities, products or services (Standards Australia/Standards New Zealand, 2001b:iv).
To achieve the desired long term benefits of reduced injury an illness
rates, effective management of occupational health and safety must
become an organisational objective that is clearly demonstrated across
the organisation itself.
To better understand occupational health and safety management
systems Chapter 6 identifies and analyses what occupational health
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and safety management systems are actually implemented and their
impact on occupational health and safety performance.
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Mercury exposure in fluorescent lamp manufacturing companies in Korea
3.1 Introduction
There are 6 fluorescent lamp-manufacturing companies (8 workplaces)
in Korea. According to the Industrial Safety and Health Act 1996
(Korea) and the Enforcement Regulations for Industrial Safety and
Health Act 1997 (Korea), employers in organisations in which mercury
is used should provide employees with special mercury exposure
health surveillance once a year19 including mercury in urine test and air
monitoring. As a result of this requirement and the data collected,
mercury concentrations in air of the 6 companies and mercury in urine
of total 4,140 individual cases were collected and measured in the
period 1994 to 1999.
The specific aim of this chapter is to identify and describe work-related
mercury exposures that occurred at fluorescent lamp manufacturing
companies in Korea during the period of 1994 to 199920 by using
epidemiological health surveillance data with low and moderate
mercury exposure in lamp manufacturing workers. It will assess the
usefulness and robustness of the monitoring system itself, as this is an
essential component of the occupational health management process
in Korea. The data were obtained from the Department of Preventative
Medicine and Institute for Environmental Health, Korea University that
had been assigned by the Korean Government to make special
epidemiological investigations following an outbreak of occupational
19 In exceptional circumstances (see section 2.3.1.1.2) surveillance may take place twice a year. 20 The time frame 1994-1999 was dictated by the availability of data at the commencement of the study. The author was involved, as a research assistant, in the collection of some of this data.
3
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mercury poisoning in a fluorescent lamp manufacturing company in
1989. Using this data, an assessment will be made of the protection
offered by the Korean Legislation to the health and safety of the
workforce in these companies. An analysis of the data will also allow
some conclusions to be drawn with respect of the performance of the
Regulatory regimen.
The retrospective study examined 4,140 individual cases of biological
monitoring. The results presented in this chapter mainly describe the
extent of mercury exposure levels and the follow-up management of
mercury exposures to workers.
The results of this chapter may assist in quantifying the impacts of
mercury exposure on worker’s health and information that may be
useful in helping to prevent mercury exposure in fluorescent lamp
manufacturing companies. An understanding of the health of workers
exposed to mercury in fluorescent lamp manufacturing companies in
Korea will provide an insight into the effectiveness of the legislation
regulating health and safety in these companies and the occupational
health and safety management systems in place.
3.2 The process of epidemiological data collection
3.2.1 Study subjects
For the Korean study, epidemiological data including air monitoring and
4,140 individual cases health surveillance data for mercury exposure
over 6 years (1994-1999) has been obtained from 6 fluorescent lamp
manufacturing companies in 8 workplaces in Korea. The health
surveillance data was collected to identify the extent of mercury vapour
exposure and the health outcomes of workers. The health surveillance
system for mercury and other substances has been outlined in the
literature review. As noted above, the data were obtained from the
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Department of Preventative Medicine and Institute for Environmental
Health, Korea University.
3.2.2 Air Monitoring Methods
There are two broad groupings of monitoring methods. They differ in
their objectives and in the techniques used for monitoring.
Personal monitoring aims to reveal the concentration levels to
which a worker is exposed during a full-shift or during a task. This
method focuses on worker exposure and uses sampling equipment
that at times may interfere with normal work procedures
Area monitoring is used to determine the general, background
concentration level experienced by most workers in the area. This
method focuses on plant conditions and uses portable methods.
In the air monitoring conducted by the same Institute that carried out
health surveillance. Air concentrations were monitored over full shifts to
estimate time weighted average (TWA) exposures. Shorter monitoring
periods were also used when health-effects indicated a need to
estimate the potential contribution of particular tasks to a worker's total
exposure profile.
The full-shift sampling, while relatively simple, has the disadvantage
that peak exposure information is usually lost. There is no way to
identify which tasks led to peaks. A proper mix of full-shift and short-
term task sampling is usually the best technique for evaluating
personnel exposures (Hawkins, Norwood et al., 1991).
For personal air sampling a Gillian, instruCorp (Indoor air sample
pump: Flow Rate; 750-5000 cc/min) U.S.A was used for air monitoring
in each production line in the 6 companies. Samples were collected
from the workers’ respiratory area for 30 min (1.5 l/min) 6 times during
a shift. In addition general, environmental air sampling was undertaken
at selected places throughout the workplace. Air monitoring was
Mercury exposure in fluorescent lamp manufacturing companies in Korea
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conducted once a year, or twice in any year immediately following a
year in which levels in excess of the Baseline Level were detected.
3.3 Background
3.3.1 Mercury Exposure
Exposure to and the toxicology of mercury was discussed extensively
in Chapter 2. The following is a revision of some of the points raised in
the literature and some additional information on mercury use in Korea.
A number of Government authorities and authors (Occupational Safety
and Health Administration, 1975); (National Institute of Occupational
Safety and Health, 1977); (Occupational Safety and Health
Administration, 1989); (Campbell, Gonzales et al., 1992) have identified
the widespread use of mercury and the large number of workers
potentially exposed to mercury vapour. The primary source of mercury
exposure in the workplace has been identified as being through the
inhalation of airborne elemental mercury vapour. A number of studies,
involving the biological monitoring of mercury workers, have identified
excessive exposures to mercury vapour in mining, thermometer and
some fluorescent lamp manufacturing industries (Gonzalez-Fernandez,
Mean et al., 1984); (Kim & Cha, 1990); (Ehrenberg, Vogt et al., 1991);
(Cha, Kim et al., 1992); (Kishi, Doi et al., 1993); (Kishi, 1994); (Yang,
Huang et al., 1994).
As world production and usage of mercury rapidly increased in the 20th
century, it became apparent that mercury was a widespread hazard
that would present itself to humans, not only in the mining and industrial
use of the metal but also in the home, in the school, and in food. Jang,
Kim et al. (Jang, Kim et al., 1989) estimated the world production of
mercury at 12, 000 tons per year. Korea uses about 0.25% of this
production (about 30, 000 Kg); all is imported from other countries, as
there is no domestic production. The amount of mercury imported
Mercury exposure in fluorescent lamp manufacturing companies in Korea
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increased year by year from 14,179kg in 1985, 17,032 kg in 1986, and
28,447kg in 1987.
Because of the extent of mercury poisoning and the adverse effects
resulting from mercury poisoning, it is important to thoroughly
investigate the workplace for sources of potential contamination. Liquid
elemental mercury can exist in this form for years in many workplaces.
The liquid can lie in cracks and crevices in floors. An area in which
elemental mercury has been used or is used should be viewed with
caution as an area of potential mercury vapour.
The biological exposure indices established for mercury in blood and
urine and Korea are repeated in Table 3.1.
Table 3.1: Korean biological exposure indices for mercury
Variables Baseline value Warning level Diagnostic Value
Hg in blood (µg/dL) < 3.5 3.5 - 20 > 20
Hg in urine (µg/L) < 100 100 - 300 > 300
3.3.2 Fluorescent Lamps
Fluorescent light bulbs (lamps) and high intensity discharge (HID)
lamps are energy–efficient lighting sources that use 75 percent less
electricity than incandescent lights for a given amount of luminescence.
Current technology requires the use of at least a small amount of
mercury for fluorescent lamps to function properly. Eliminating mercury
would lower lamp efficiency and shorten bulb life (Howley, Joseph, GE
Lighting. Letter to US EPA dated August 20, 1996).
Fluorescent lamps are used in residential, office, commercial and
institutional applications. Fluorescent lamp manufacturing is thought to
be the largest source of mercury exposure in Korea, accounting for an
estimated 1,200 tons of mercury nationwide in 1987 (Jang, Kim et al.,
1989). There is no recent data (post 1987) available on the use of
mercury in Korea.
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3.4 Method
3.4.1 Sources and components of secondary epidemiological data
Considerable epidemiological data was collected from workers in
fluorescent lamp manufacturing companies in Korea by the
Department of Preventive Medicine & Institute for Environmental
Health College of Medicine, Korea University over the six years from
1994 to 1999. This data includes air levels of mercury, biological levels
and general health assessments obtained by Korea University and
made available to the author for secondary analysis.
The information made available includes:
Demographic data (Name of company, date of birth, sex, date of
starting employment, job title, previous employment);
Occupational history;
Medical history;
Physical examination with an emphasis on neurological,
gastrointestinal, renal and cutaneous systems;
Biological monitoring, mercury in urine and, where appropriate,
mercury in blood;
Air monitoring data, airborne mercury concentrations in the
workplace.
The sampling, analysis and storage of biological samples is strictly
controlled in Korea and the approved agencies undergo regular
auditing to ensure that they maintain strict quality control procedures.
The methods used for sampling, analysis and storage of biological
samples of urine and blood collected as part of the compulsory medical
examinations to ascertain the extent of mercury exposure are in
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accordance with the procedure established by Clarkson, Friberg, et al
(1988b) and recommended by the World Health Organisation (1976).
The analysis is by atomic absorption of cold vapour (CVAA) as
recommended by the World Health Organisation (1976). Correction of
concentration by reference to urine specific gravity (SG 1.014) is
undertaken.
Data for this study were obtained as a result of the compulsory regime
of medical examinations required by Korean Legislation. In the 6 lamp-
manufacturing companies located in Korea, workers who may have
been exposed to mercury vapour during their job are required to be
monitored for mercury exposure. Over the 6-year time period from
1994 to 1999 4,140 first round urine samples were collected. Of these
1350 (32.6%) samples were taken from female workers, and 2790
(67.4%) from male workers. It has not been possible to determine the
exact number of workers monitored as individual case identities were
not recorded. (Note: In this Chapter, when data on gender is
presented, it refers to the samples taken from males and females and
not to the absolute number of males and females from whom the
samples were taken unless specifically noted.)
3.5 Analysis
Data was entered in SPSS (Version 10.1.0) for Windows for advanced
data analysis.
As is common with much occupational health surveillance data, most of
the biological monitoring data was strongly positively skewed. See for
example Figure 3.1 and Figure 3.2 representing the levels of mercury
in urine and blood respectively for the sample population.
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Mercury concentration in urine - initial test
2600.0
2400.0
2200.0
2000.0
1800.0
1600.0
1400.0
1200.0
1000.0
800.0600.0
400.0200.0
0.0
4000
3000
2000
1000
0
Std. Dev = 100.00 Mean = 44.4
N = 4140.00
Figure 3.1: Histogram of mercury levels in urine
Mercury concentration in blood - initial test
80.075.0
70.065.0
60.055.0
50.045.0
40.035.0
30.025.0
20.015.0
10.05.00.0
1600
1400
1200
1000
800
600
400
200
0
Std. Dev = 2.78 Mean = 1.1
N = 1846.00
Figure 3.2: Histogram of mercury levels in blood
The data also contains a number of outliers which strongly affect the
results. For example the mean and 5% trimmed mean for each of the
above variables were quite different. The original means for mercury
levels in urine and mercury levels in blood for the sample population
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-111-
were 44.4µg/L and 1.1µg/dL respectively. The 5% trimmed means21
were 30.2 µg/L and 0.7 µg/dL respectively.
Although a small improvement was obtained with square root
transformed data, (See Figure 3.3 and Figure 3. 4) the results were still
not considered to be normally distributed and were still strongly
affected by outliers.
Square root data: Mercury concentrations in urine - initial test
10.009.00
8.007.00
6.005.00
4.003.00
2.001.00
0.00
3000
2000
1000
0
Std. Dev = .78 Mean = .33
N = 4123.00
Figure 3.3: Histogram of square root transformed data for mercury levels in urine
21 The top and bottom 5% of cases are trimmed and the mean recalculated. This demonstrates the effect of outliers on the mean. A large difference demonstrates that the outliers have a strong influence on the mean.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-112-
Square root data: Mercury concentrations in blood - initial test
18.017.0
16.015.0
14.013.0
12.011.0
10.09.0
8.07.0
6.05.0
4.03.0
2.01.0
0.0
1200
1000
800
600
400
200
0
Std. Dev = 1.24 Mean = 1.5
N = 1650.00
Figure 3.4: Histogram of square root transformed data of mercury levels in blood
In this instance, the original mean for mercury levels in urine and blood
(square root transformed were 0.3 µg/L and 1.5 µg/dL respectively and
the 5% trimmed means were 0.2 µg/L and 1.3 µg/dL. In both instances
the trimmed mean was below the lower 95% confidence level of the
original mean.
A decision, discussed later in this chapter, was taken not to exclude the
outliers. For these reasons median, minimum and maximum levels are
used to describe data distribution and non-parametric equivalents
(Mann-Whitney Test for unpaired t-test, Wilcoxon Signed Ranks Test
for paired t-test, Kruskal-Wallis Test for one-way between groups
ANOVA) have been used when analysing this data. These tests also
have the impact of reducing the effects of outliers. Descriptive statistics
are based on counts and percentages.
Where continuous data was found to meet the requirements of
normality, standard univariate statistics were used to determine
variable associations.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
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Significance was set at a two-tail ρ value of 0.05.
3.6 Results
3.6.1 Demographics of study group
Mercury levels in air, urine, and blood were studied for mercury-
exposed workers employed in the 8 workplaces of the 6 fluorescent
lamp manufacturing companies in Korea over the 6-year period 1994
to 1999. Over the 6 year period 4140 special health check-ups (1350
of women, 2790 of men) were conducted in the 8 workplaces.
It should be noted that the data has been collected over a period of 6
years and there are multiple data points for each individual. As the
data does not allow the identification of individuals, the exact number of
males and females in the total study period can not be obtained, only
the number of male and female collections can be stated.
Data were obtained from 8 workplaces. Ages of the persons from who
samples were collected ranged from 17 to 67 years. The mean age
over the six year served was 32 years.
The breakdown by workplace of the number of persons undergoing
special check-ups, including their mean age, gender and the results of
tests for mercury levels in urine and in blood are shown in Table 3.1.
3.6.2 Initial tests
Table 3.2 illustrates that in total, some 4140 urine samples were
collected over the 6-year period and tested for mercury levels in urine
(median 19.1 µg/L, min <0.1 µg/L, max 2576.2 µg/L) as part of the
required biannual special health check-ups. One thousand eight
hundred and forty six (1846) were tested at the same time for mercury
levels in their blood (median 0.6 µg/dL, min <0.1 µg/dL, max 80.9
µg/dL). Of the workers who were tested for mercury in their blood, 9
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-114-
did not have results for mercury concentrations in their urine. Thus
4149 workers were tested.
Table 3.2: General demographic characteristics of workplaces (1994-1999)
Workplace A B C D E F G H Total
Mean Age (±SD) 41 (±13)
32 (±6) 28 (±3) 31 (±8) 31 (±7) 34 (±8) 28 (±4) 31 (±8) 32 (±9)
M 235 270 64 555 998 137 326 225 2811 Sex
F 422 4 0 252 433 30 89 134 1364
No of samples collected
652 272 63 355 800 163 1420 415 4140 Hg in Urine level Median
(µg/L) (Min~Max)
58.8 (<0.1~2576.1)
27.9 (<0.1-379.6)
14.0 (1.1-307.5)
15.2 (<0.1-164.8)
25.6 (<0.1-868.3)
34.8 (2.6-430.5)
10.1 (<0.1-583.3)
25.0 (<0.1-312.5)
19.1 (<0.1-2576.1)
Samples collected
299 111 39 84 198 51 993 71 1846 Hg in Blood level Median
(µg/dL) (Min~Max)
1.3 (<0.1-80.8)
0.7 (<0.1-0.8)
0.5 (<0.1-0.7)
0.5 (<0.1-12.5)
0.8 (<0.1-13.8)
1.0 (<0.1-6.1)
0.4 (<0.1-42.1)
0.9 (<0.1-6.6)
0.6 (<0.1-80.6)
Workplaces C, E and F, H are divisions of the same companies.
Investigation of the data by scatterplot revealed that any correlation
between mercury concentrations in the urine and blood of workforce
was not linear. Correlation analysis of the data was therefore not
possible.
3.6.2.1 Relationship to Baseline Levels
Of these 4149 who provided samples, 434 (10.5%) returned samples
in which the concentration of mercury in urine and/or blood exceeded
the Baseline Level (<100 µg/L for urine and <3.5 µg/dL for blood). The
median concentration of mercury in urine for this group was 146.3 µg/L
(min 0.3 µg/L, max 2576.2 µg/L). The median concentration of
mercury in blood was 2.8 µg/dL (min <0.1 µg/dL, max 80.9 µg/dL).
Of this 434, 387 had mercury concentrations in their urine (median
159.5 µg/L, min 100 µg/L, max 2576.2 µg/L) in excess of the Baseline
Level and 84 had mercury concentrations in their blood (median 6.5
µg/dL, min 3.5 µg/dL, max 80.9 µg/dL) in excess of the Baseline Level.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-115-
In 37 instances the concentration of mercury in both the urine and
blood was in excess of the Baseline Level. (Figure 3. 5).
Investigation of the data by scatterplot revealed that any correlation
between mercury concentrations in the urine and blood of workforce
was not linear. Correlation analysis of the data was therefore not
possible.
9.3
90.7
4.6
95.4
10.5
89.5
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Perc
enta
ge o
f sam
ples
ana
lyse
d
Urine Samples Blood Samples Total
Above Baseline Below Baseline
n=4140 n=1846 n=4149
Figure 3.5: Per cent of samples above and below Baseline Levels
3.6.2.2 Relationship to Diagnostic Levels
In addition to the Baseline Levels of <100 µg/L and <3.5 µg/dL for
mercury in urine and blood respectively, the Regulations also stipulate
mercury levels of 300 µg/L and 20 µg/dL in urine and blood
respectively as Diagnostic Levels at which a person is used as an
indicator of mercury poisoning.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-116-
Over the period 1994 to 1999, 81 persons recorded levels in their urine
and/or blood at Diagnostic Levels. Of these cases 4 were identified as
a result of their blood test alone. Eighteen (18) of the cases had levels
of mercury in their blood less than the Diagnostic Level but mercury in
urine levels at the Diagnostic Level.
Over the six year period (1994-1999) the overall median level of
mercury in urine at the first test (n=81) was 426.6µg/L (min 21.2 µg/L,
max 2576.2 µg/L) for persons with Diagnostic Levels of mercury in
urine and/or blood. The corresponding median value for mercury in
blood was 4.8 µg/dL (min 0.8 µg/dL, max 80.9 µg/dL).
Investigation of the data by scatterplot revealed that any correlation
between mercury concentrations in the urine and blood of workforce
was not linear. Correlation analysis of the data was therefore not
possible.
3.6.2.3 Mercury level in urine and blood by year
Mercury exposure was observed by measuring mercury concentrations
in urine and, where appropriate, blood over the period 1994-1999. The
results are summarised for urine and blood in Table 3.3. and for urine
in Figure 3.6 and blood in Figure 3.7.
Table 3.3: Results of Hg levels in urine and blood by year
1994 (No. of tests) median (min - max)
1995 (No. of tests) median (min - max)
1996 (No. of tests) median (min - max)
1997 (No. of tests) median (min - max)
1998 (No. of tests) median (min - max)
1999 (No. of tests) median (min - max)
Total (No. of tests) median (min - max)
Hg/ Urine µg/L
(722) 28.4 (<0.1-1773.5)
(655) 16.3 (0.1-1139.4)
(478) 24.7 (0.3-2067.0)
(835) 15.4 (<0.1-819.8)
(783) 18.0 (0-2576.1)
(667) 17.0 (0.1-378.4)
(4140) 19.1 (0-2576.1)
Hg/ Blood µg/dL
(1) <0.1
(4) 1.1 (0.3-6.1)
No tests done
(427) 0.2 (<0.1-80.8)
(753) 0.6 (<0.1-20.0)
(661) 0.6 (<0.1-21.2)
(1846) 0.6 (<0.1-80.6)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
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All of the median levels of mercury in urine and blood were within the
Baseline Levels (urine: <100(µg/L), blood: < 3.5(µg/dL).
1994 1995 1996 1997 1998 1999
Year
0.00
50.00
100.00
150.00
Mer
cury
con
cent
ratio
n in
urin
e - (
µg/
L ) Outliers and extreme values are hidden
28
1625
15 18 17
Figure 3.6: Boxplots of Mercury Levels in Urine by Year
Mercury in urine levels over the 6 yeas show a decreasing trend
(Figure 3.6). A statistically significant difference was found in the levels
of mercury recorded in cases’ urine by year (Kruskal-Wallis Test,
c2[5]=131.2, ρ<0.0005). The results were ranked in the order shown in
Figure 3.6.
Because relatively few blood samples were collected in the years 1994
to 1996, no analysis has been undertaken on this data. It may be
noted that number of mercury in blood tests at the time of the first urine
test, although not required by Korean Legislation, increased
dramatically in 1997 (51%) and became the norm 1998 (96% in 1998
and 99% in 1999) (Figure 3.7).
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-118-
0 1 0
51
96 99
0
10
20
30
40
50
60
70
80
90
100
Perc
enta
ge
1994 1995 1996 1997 1998 1999
Figure 3.7: Blood samples analysed by year (Expressed as a percentage of urine samples analysed in the same year)
The reasons for low numbers of mercury in blood levels being recorded
in 1994 and 1995 and no levels being recorded in 1996 are unknown.
A statistically significant difference was found in the levels of mercury
recorded in cases’ blood by year for the years 1997-1999 (Kruskal-
Wallis Test, c2[2]=102.9, df=2, ρ<0.0005). The mean ranks for each
year are shown in Table 3.3.
Table 3.4: Mean ranks of mercury in blood analysis (1997-1999)
Year N Mean Rank
1997 427 698.9
1998 753 1019.7
Mercury concentration in blood – initial test
1999 661 952.0
These data show that the mercury levels in the blood of cases was
higher in 1998 than in 1999 and 1997 respectively. The trend here is
similar to that shown in Figure 3.6 where the mercury levels in urine
were also higher in the order of 1998, 1999 and 1997 from highest to
lowest.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-119-
3.6.2.4 Gender comparisons
The median level of mercury in the urine of male workers (n=2790)
tested over the six year period was 20.2 µg/L (minimum <0.1µg/L,
maximum 2576.2µg/L) and this was significantly higher (Mann-Whitney
U Z=-5.5536, ρ<0.0005) than that in the urine of tested female workers
(n=1350, median 16.9µg/L, minimum <0.1µg/L, maximum 538.0µg/L)
(Figure 3.8).
Male Female
Gender
0.00
20.00
40.00
60.00
80.00
100.00
Mer
cury
con
cent
ratio
n in
urin
e - (
µg/
L)
Outliers and extremevalues are hidden
20.2 16.9
Figure 3.8: Boxplots of Hg levels in urine by gender (1994-1999)
There is also a significant difference (Chi-Squared Test, c2[1]=20.4, p <
0.001) between the proportion of male and female workers with
mercury levels in their urine above the Baseline Level. For urine
mercury levels, 94% of female workers were classified as having levels
below the Baseline Level, but only 89% of male workers are classified
in the same range (Figure 3. 9).
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-120-
89 94
11 6
0102030405060708090
100
Perc
enta
ge
Less than 100µg/L Equal to or greater than100µg/L
Male Female
Figure 3.9: Comparison of Hg in urine by gender (1994-1999)
3.6.2.5 Workplace comparisons
The median level of mercury in the urine of workers in the eight
workplaces monitored over the period 1994 to 1999 also varied
considerably. This relationship is shown in Table 3.5.
Table 3.5: Median level of Hg in urine by Workplace (1994-1999)
Workplace Number of cases Median level of Hg in urine µg/L
Minimum level of Hg in urine µg/L
Maximum level of Hg in urine µg/L
A 652 58.9 <0.1 2576.2
B 272 27.9 <0.1 393.6
C 63 14.0 1.2 307.5
D 355 15.2 <0.1 164.8
E 800 25.6 <0.1 868.3
F 163 34.8 2.7 430.5
G 1420 10.1 <0.1 583.3
H 415 25.1 <0.1 312.5
Total number 4140
Mean of Median levels 19.1
Mean of Minimum levels <0.1
Mean of Maximum levels 2576.2
For greater clarity, this relationship is presented graphically in Figure
3.10. There was a statistically significant difference in the levels of
mercury in the urine of cases by workplace (Kruskal-Wallis
c2[7]=1176.6, ρ<0.0005). An inspection of the mean ranks suggests
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-121-
that Worklace A had the highest exposure and that Workplace G the
lowest (Table 3.7).
Workplace
0.00
100.00
200.00
300.00M
ercu
ry c
once
ntra
tion
in u
rine
- (µ
g/L)
Outliers and extreme values are hidden
59
2814 15
26 35 2510
A B C D E F G H
Figure 3.10: Boxplots of Hg levels in urine by Workplace (1994-1999)
An analysis of the relationship between workplace and the levels of
mercury in the urine of workers at the time of their first urine test each
year also showed a statistically significant relationship (Chi-Square
Analysis, c2[7]=551.7, ρ≤0.001) between the level of mercury in the
urine (with respect to the Baseline Level) and workplace (Figure 3.11).
A much higher percentage of workers at Workplace A had mercury in
urine levels above the Baseline Level than those at the other
workplaces.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-122-
68
32
92
8
97
3
97
3
90
10
88
12
100
0
92
80
102030405060708090
100
Perc
enta
ge
A B C D E F G H
Workplace
<100µg/L ≥100µg/L
Figure 3.11: Comparison of Hg levels in urine by workplace (1994-1999)
The number of cases reported each year with mercury levels in their
urine above the Diagnostic Level at the time of the first special health
check-up is shown in Table 3.6.
Table 3.6: Cases of Diagnostic Levels by workplace and year
Year 1994 1995 1996 1997 1998 1999 Total
Workplace A 12 9 14 17 8 3 63
Workplace B 0 0 1 0 0 0 1
Workplace C 0 0 0 0 0 0 1
Workplace D 0 0 0 0 0 0 0
Workplace E 6 2 0 0 2 0 10
Workplace F 0 1 0 0 1 0 2
Workplace G 1 0 0 1 1 0 3
Workplace H 0 0 0 1 0 0 1
Total 19 12 15 19 13 3 81
The majority (78%) of the cases of Diagnostic Level recorded over the
period 1994-1999 occurred in Workplace A. The fall in the number of
cases recorded in 1999 is largely a result of the fall in recorded cases
in Workplace A (Figure 3.12).
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-123-
0102030405060708090
100
Perc
enta
ge
1994 1995 1996 1997 1998 1999 Total
Workplace A Workplace B Workplace C Workplace DWorkplace E Workplace F Workplace G Workplace H
Figure 3.12: Annual cases of Diagnostic Levels by workplace (The % of cases attributable to each of the 8 workplace is given for each year from 1994 to 1999 and the total for this period is also shown)
Table 3.7 demonstrates the change in the median level of mercury in
the urine of people tested in each Workplace over the period 1994 to
1999. The data relates to the first urine sample taken in each special
health check-up only.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-124-
Table 3.7: Median Hg in Urine in Workplaces by Year
Workplace 1994 Median min – max (No.)
1995 Median min – max (No.)
1996 Median min – max (No.)
1997 Median min – max (No.)
1998 Median min – max (No.)
1999 Median min – max (No.)
Workplace A 54.6µg/L <0.1-1773.5 (111)
79.9µg/L 0.1-1139.5 (63)
77.2µg/L 0.3-2067.0 (102)
71.6µg/L 1.3-819.8 (108)
62.9µg/L 0.6-2576.2 (148)
31.6µg/L 5.3-378.4 (120)
Workplace B 48.9µg/L <0.1-172.3 (44)
16.5µg/L 0.5-98.2 (53)
43.5µg/L 1.7-379.6 (37)
31.0µg/L 0.8-263.5 (37)
25.9µg/L 2.6-172.2 (47)
28.2µg/L 4.1-101.4 (47)
Workplace C No data available
7.2µg/L 1.2-29.4 (7)
9.9µg/L 1.9-38.9 (9)
23.6µg/L 7.3-73.5 (15)
17.5µg/L 4.0-307.5 (14)
13.6µg/L 3.8-94.0 (18)
Workplace D 29.9µg/L 4.0-164.8 (100)
5.6µg/L 1.0-92.7 (65)
8.3µg/L 0.7-60.9 (56)
9.8µg/L <0.1-63.4 (81)
19.4µg/L <0.1-124.8 (53)
No data available
Workplace E 29.9µg/L <0.1-805.6 (209)
20.6µg/L 0.3-868.3 (169)
22.9µg/L 2.3-150.5 (152)
24.9µg/L <0.1-216.0 (144)
67.6µg/L 17.9-342.8 (51)
28.6µg/L 7.2-162.7 (75)
Workplace F 49.5µg/L 2.8-252.4 (38)
37.1µg/L 8.5-430.5 (32)
28.0µg/L 2.7-114.7 (45)
28.1µg/L 5.1-82.5 (16)
67.1µg/L 16.3-404.7 (18)
44.7µg/L 6.5-210.7 (14)
Workplace G 16.1µg/L <0.1-583.3 (87)
7.3µg/L 0.5-68.4 (145)
No data available
9.9µg/L <0.1-132.5 (397)
9.8µg/L 0.3-477.2 (428)
10.8µg/L 0.2-125.7 (363)
Workplace H 19.7µg/L <0.1-262.0 (133)
23.6µg/L 2.7-176.6 (121)
16.6µg/L 1.2-134.6 (70)
30.71µg/L 0.2-312.5 (31)
34.7µg/L 11.6-164.3 (24)
598.0µg/L 15.4-248.7 (30)
Figure 3.13 shows these median levels of mercury in the urine of
workers at the time of the first test plotted over the years 1994 to 1999
for each workplace. For comparison, the median levels of mercury in
the blood of workers at the time of the first test plotted over the years
1997 to 199922 for each workplace are shown in Figure 3.14.
The Krusal-Wallis Test was used to compare the mercury in urine
levels for each of the companies over the period 1994 to 1999. A
significant difference was found in the levels of mercury in the urine of
workers:
22 Because of the low number of blood samples collected in 1994-1996 only the years 1997-199 are shown.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-125-
In Workplace A over the period 1994-1999 (c2[5]=50.9,
ρ<0.0005). Figure 3.13 indicates a downward trend with the
highest ranked level in 1995 and the lowest in 1999;
In Workplace B over the period 1994-1999 (c2[5]=21.4,
ρ=0.001). Figure 3.13 indicates a downward trend with the
highest ranked level in 1996 and the lowest in 1995. The levels
in 1998 and 1999 were the second and third lowest ranked
respectively;
In Workplace C over the period 1995-1999 (c2[4]=10.4,
ρ=0.034), Figure 3.13 indicates an upward trend with the
highest ranked level in 1997 and the lowest in 1995;
In Workplace D over the period 1994-1998 (c2[4]=131.1,
ρ<0.0005). Figure 3.13 suggests a slight downward trend with
the highest ranked level in 1994 and the lowest in 1995. The
second highest ranked level was in 1998;
In Workplace E over the period 1994-1999 (c2[5]=71.9,
ρ<0.0005). Figure 3.13 suggests a slight upward trend with the
highest ranked level was 998 and the lowest in 1995. The
second highest level was in 1999;
In Workplace F over the period 1994-1999 (c2[5]=11.1,
ρ=0.048). Figure 3.13 suggests an upward trend with the
highest ranked level in 1998 and the lowest in 1996;
In Workplace G over the period 1994-1999 23 (c2[4]=44.0,
ρ<0.0005). It is not possible to determine a trend from a visual
inspection of Figure 3.13. The highest ranked level was in 1999
and the lowest in 1995; and
23 No data was available for 1996.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-126-
In Workplace H over the period 1994-1999 (c2[5]=50.2, ρ<0.0005).
Figure 3.13 suggests an upward trend with the highest ranked level in
1999 and the lowest in 1996.
0
1020
3040
5060
7080
90
1994 1995 1996 1997 1998 1999
Hg
in u
rine
µg/L
Workplace A Workplace B Workplace C Workplace DWorkplace E Workplace F Workplace G Workplace H
Figure 3.13: Plot of Median Hg levels in urine by workplace and year
The Krusal-Wallis Test was used to compare the mercury in blood
levels for each of the companies over the period 1997 to 1999 (Figure
3.14). A significant difference was found in the levels of mercury in the
blood of workers in the period 1997-1999:
In Workplace A (c2[2]=13.9, ρ=0.001). The highest ranked level
was in 1997 and the lowest in 1999;
In Workplace C (c2[2]=10.2, ρ=0.006). The highest ranked level
was in 1998 and the lowest in 1998;
In Workplace D24 (c2[2]=21.4, ρ<0.0005). The highest ranked
level was in 1998 and the lowest in 1997;
24 In Workplace D no results were recorded for 1997 so these statistics refer to the years 1998 and 1999 only.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-127-
In Workplace E (c2[2]=48.4, ρ<0.0005). The highest ranked
level was in 1999 and the lowest in 1998;
In Workplace F (c2[2]=6.6, ρ=0.036). The highest ranked level
was in 1998 and the lowest in 1997; and
In Workplace G (c2[2]=33.0, ρ<0.0005). The highest ranked
level was in 1998 and the lowest in 1997.
No significant difference was found in the mercury levels in the blood of
cases over the period 1997-1999 in Workplace B (c2[2]=4.2, ρ=0.122)
or Workplace H (c2[2]=1.6, ρ=0.456).
0
0.5
1
1.5
2
2.5
1997 1998 1999
Hg
in b
lood
µg/
dL
Workplace A Workplace B Workplace C Workplace DWorkplace E Workplace F Workplace G Workplace H
Figure 3.14: Plot of Median Hg levels in blood by workplace and year
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-128-
3.6.3 Follow-up tests for mercury levels in urine and blood
Because of the complexity of the testing and follow-up testing process,
a flow chart of the process is presented in Figure 3.15. This shows the
number of persons undergoing the special check-up (the 9 persons
who had blood tests only at this check-up have been omitted as none
went on to have further testing) and the follow-up tests they received.
The Figure also notes whether the results of the urine and blood tests
were normal or abnormal (below or above the Baseline Levels
respectively).
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-129-
Note: Figure does not show 9 cases who underwent blood testing only in the initial tests. Not all cases underwent follow-up testing as required by Regulation. Urine only: Number of workers who underwent mercury in urine test only Blood only: Number of workers who underwent mercury in blood test only Blood & urine: Number of workers who underwent both mercury in urine and blood test N: normal findings of the test (below the Baseline Level) AB: Abnormal findings of the test (above the Baseline Level) ( ): number of workers who underwent biological monitoring Figure 3.15: Biological monitoring process and results
Biological Monitoring (n=4140, 1994- 1999) Initial Tests
Follow-up tests
Urine Only (n=2303)
Blood & Urine (n=1837)
AB (255) N urine & AB blood (47)
AB urine & N blood (95)
AB blood & AB urine (37) N (2048) N urine & N
blood
Urine only (56)
Urine & Blood (63)
Blood only (9)
n= 179
Blood only (2)
Urine only (3)
Blood & Urine (130)
N (19)
N (42)
N (0) AB urine (30
AB urine
& blood (21)
AB blood
(1)
AB blood
(9)
N (1) N (1) AB (2)
AB (1)
AB blood & N urine
(6)
AB urine & N blood
(42)
AB blood & AB
urine (31)
AB (37)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-130-
3.6.4 Comparison of first and second round tests
3.6.4.1 Urine and Blood Tests
For the 387 workers who had elevated mercury in urine levels (i.e.
≥100µg/L), 231 underwent second mercury in urine tests. For this
latter group, the median level of mercury in the urine fell from median
levels of 176.2µg/L (min 100.2µg/L, max 2576.2µg/L) to 129.3µg/L
(min 4.9µg/L, max 1855.1µg/L). This was a statistically significant
difference when tested using the Wilcoxon Signed Ranks Test (z=-
4.680, ρ<0.0005) (Figure 3.16). The level at the second test was lower
than that at the first.
0
100
200
300
400
500
176.2
120.3
Outliers and extreme values are hidden
First test Second test
Figure 3.16: Boxplots of mercury levels at first and second test for those exceeding Baseline Level at first test (1994-1999)
Comparative analysis between blood tests is only possible for those
132 workers who underwent testing for mercury in blood at the time of
the first test for mercury in urine and then underwent a second series of
Hg
in u
rine
(µg/
L)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-131-
blood tests. In the six years, three of those who returned results in the
normal range of mercury for both blood and urine underwent further
blood tests. These results have been excluded from the following
analysis.
Although the median levels of mercury in the blood decreased from
2.24 µg/dL (min <0.1 µg/dL, max 80.86 µg/dL) to 2.16µg/dL (min 0.03
µg/dL, max 31.35 µg/dL) between the first and second tests, the
decrease was not significantly different when tested using the Wilcoxon
Signed Test (z=-0.289, ρ=0.772) (Figure 3.17).
0
2
4
6
8
10
12
2.24 2.16
Outliers and extreme values are hidden
First test Second test
Figure 3.17: Boxplots of mercury levels in first and second blood tests (1994-1999)
3.6.4.2 Diagnostic Levels
Of the 81 persons who were identified as having blood or urine
mercury concentrations at the Diagnostic Level at the first test, 57
(70%) underwent further testing as required by the Regulations. Forty
three (43) had both urine and blood tested; 1 had blood tested only and
13 had urine tested only.
Hg in
blo
od (µ
g/dL
)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-132-
The median level of mercury in urine fell from 426.6 µg/L in the first test
to 311.6 µg/L (min 4.9 µg/L, max 1855.1 µg/L) (Figure 3.18). This was
a statistically significant difference (Wilcoxon Signed Ranks Test Z=-
3.2, ρ=0.001). The level at the second test was lower than that at the
first.
0
200
400
600
800
1,000
1,200
426.6
311.6
Outliers and extreme values are hidden
First test Second test
Figure 3.18: Boxplots of concentrations of Hg in urine for those in the Diagnostic Level range (1994-1999)
Similarly, median mercury in blood levels fell from 5.5 µg/dL (min 0.8
µg/dL, max 80.9 µg/dL)in the first test to 4.8 µg/dL (min 1.2 µg/dL, max
31.4 µg/dL) in the second test for those 18 who underwent blood
testing on both occasions (Figure 3.19). However, the fall in mercury in
blood levels in these two tests was not significantly different (Wilcoxon
Signed Ranks Test Z=-0.501, ρ= 0.616).
Hg
in u
rine
(µg/
L)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-133-
0
5
10
15
20
5.54.8
Outliers and extreme values are hidden
First test Second test
Figure 3.19: Boxplots of concentrations of Hg in blood for those in the Diagnostic Level range (1994-1999)
Over the six-year period, of the 81 persons with mercury in urine or
blood above Diagnostic Levels at their first test, 57 underwent second,
follow-up testing as required by Regulation. Twenty-eight (28, 35%) of
these persons still had levels of mercury in their urine or blood in the
Diagnostic Level range.
3.6.5 Comparison of follow up tests by year
3.6.5.1 Diagnostic Levels
The reduction of the number of persons at Diagnostic Levels between
the first and second urine and/or blood tests has not changed greatly
over the six year period 1994 – 1999 (Figure 3.20). It is noted
however, that far fewer persons were found to have urine and/or blood
tests at the Diagnostic Level in 1999.
Hg in
blo
od (µ
g/dL
)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-134-
1918
12
7
15
8
19
10
7
10
1312
1312
3
1
3
102468
101214161820
No.
of C
ases
at D
iagn
ostic
Le
vel
1994 1995 1996 1997 1998 1999
Urine test 1 Urine test 2 Blood test 1 Blood test 2
Figure 3.20: Comparison of cases at Diagnostic Level by year
When tested using Chi-Square Analysis there was no significant
reduction in the number of cases with mercury in urine concentrations
at Diagnostic Levels between the first or second tests (c2[4]=2.57,
ρ=0.738) for the years 1994 – 1998 inclusive. Results for the year
1999 were not included in statistical testing because of the small
number of cases involved. Similarly, there was no statistically
significant difference in the number of cases with mercury in blood
concentrations at Diagnostic Levels between the first and second tests
in the years 1997 and 1998 (Chi-Square Analysis, c2[1]=0.47,
ρ=0.491).
As noted previously, the overall median concentration of mercury in the
urine of the 81 persons at Diagnostic Levels fell significantly between
the first and second tests.
The fall in mercury concentrations in mercury in urine between the first
and second tests is not uniform across years (Figure 3.21). Using the
Wilcoxon Signed Rank Test no significant difference was found in the
concentrations in 1994 (Z=-1.459, ρ=0.145), 1996 (Z=-0.980, ρ=0.327),
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-135-
1997 (Z=-0.764, ρ=0.445), 1998 (Z=-1.804, ρ=0.071) and there were
insufficient cases to statistically analyse the results for 1999. In 1995
there was a significant reduction in the concentrations of mercury in
urine between the first and second tests (Z=-2.028, ρ=0.043) (Figure
3.21).
1994 1995 1996 1997 1998 1999
year
0
300
600
900
1,200
1,500
391/328
431/120
572/404
381/398
441/397
378/19
Mercury concentration in urine - initial testResult of second urine test Outliers and extreme
values are hidden
Figure 3.21: Comparison of first and second urine analyses for those at Diagnostic Levels25
Using the Wilcoxon Signed Rank Test no significant difference was
found in the concentrations of mercury in the blood of cases in the first
and second tests in 1997 (Z=-0.405, ρ=0.686) and 1998 (Z=1.255,
ρ=0.209) for those who underwent both tests. There were an
insufficient number of cases to test for any difference in the other years
(Figure 3.22).
25 Values given in 1999 are for a single worker only.
Hg
in u
rine
(µg/
L)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-136-
1997 1998 1999
year
0.00
20.00
40.00
60.00
80.00
100.00
5.9/4.7
6.2/10.9
2.9/11.7
Mercury concentration in blood - initial testResult of second blood test
Figure 3.22: Comparison of first and second blood tests for those at Diagnostic Levels26
3.6.6 Regulatory compliance
3.6.6.1 Initial Testing
With the exception of 1996, the number of persons undergoing the first
level urine testing each year has not varied dramatically (Figure 3.23).
However, an analysis of the number of first round tests per workplace
per year presents a slightly different picture (Figure 3.24).
The number of tests in some workplaces varies substantially by year.
No data are available on the employment figures for each workplace.
26 Values given in 1999 are for a single worker only.
Hg in
blo
od (µ
g/dL
)
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-137-
722655
478
835783
667
0
100
200
300
400
500
600
700
800
900
Num
ber o
f urin
e sa
mpl
es
1994 1995 1996 1997 1998 1999
Figure 3.23: Number of first round urine samples analysed by year
0
50
100
150
200
250
300
350
400
450
No.
of t
ests
Workplac
e A
Workplac
e B
Workplac
e C
Workplac
e D
Workplac
e E
Workplac
e F
Workplac
e G
Workplac
e H
1994 1995 1996 1997 1998 1999
Figure 3.24: Urine tests per workplace per year
3.6.6.2 Follow-up Testing
The basis for referral for further testing, as outlined in the Regulation, is
having mercury in urine or blood levels in excess of the Baseline Level
(>100 µg/L for urine, > 3.5 µg/dL for blood). Over the six-year period,
434 urine and/or blood samples showed mercury levels in excess of
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-138-
the Baseline Level (Figure 3.15). The percentage of urine and/or blood
samples over the baseline level for each year from 1994 to 1999 is
shown in Figure 3.25. There was a general decline in the percentage
of persons with urine and/or blood samples over the baseline level in
the period 1994 to 1999.
14
7
13
11 11
7
0
2
4
6
8
10
12
14
Perc
ent
1994 1995 1996 1997 1998 1999
Figure 3.25: Urine and/or blood samples in excess of Baseline Level by year
Of the 434 cases with mercury levels in their urine and/or blood
samples in excess of the Baseline Level, 193 persons (44%)
underwent both further testing for mercury levels in blood and urine as
required by the Regulation. Two hundred and sixty three persons
(61%) underwent further testing, either blood or urine or both (Table
3.7). The data presented in Table 3.7 shows that the percentage of
persons who have undergone further testing as a result of having
mercury in their urine or blood samples in excess of the Baseline Level
over the years 1994-1999.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-139-
Table 3.8: Follow-up biological monitoring tests by year27
1994 No. (%)
1995 No. (%)
1996 No. (%)
1997 No. (%)
1998 No. (%)
1999 No. (%)
Total 1994-1999 No. (%)
Urine and/or samples at or in excess of Baseline Level
100 (14%)
47 (7%)
64 (13%)
89 (11%)
87 (11%)
47 (7%)
434 (10%)
Resultant number of blood samples analysed
32 (4%) [32%]
11 (2%) [23%]
9 (2%) [14%]
44 (5%) [49%]
70 (9%) [80%]
38 (6%) [81%]
204 (5%) [47%]
Resultant number of second urine samples analysed
34 (5%) [34%]
16 (2%) [34%]
34 (7%) [53%]
58 (7%) [65%]
71 (9%) [82%]
39 (6%) [83%]
252 (6%) [58%]
Number of persons referred for both blood and urine analysis
32 (4%) [32%]
11 (2%) [23%]
0 42 (5%) [47%]
70 (9%) [80%]
38 (6%) [81%]
193 (5%) [44%]
Figures in ( ) brackets represent the percentage of the total population tested in that year Figures in [ ] brackets represent the percentage persons above the Baseline Level in that year.
Although the total percentage of persons receiving both blood and
urine follow-up biological tests as required by the Regulation over the 6
years is 44%, the levels have increased from relatively low percentages
in 1994 to 1997 to around 80% in 1998 and 1999 (Table 3.7).
3.7 Discussion
3.7.1 Outliers
As previously noted in the section on Analysis in this Chapter (see 3.5
page 109) a decision was made to include outliers in the analysis of
results. This decision was based partly on personal communication (Dr
Choi 16/6/03) that the extreme results had been reanalysed in Korea
and were found to be correct with correct analytical procedures. For
example, 32 cases were recorded with mercury in urine levels at the
time of the first test at or in excess of 500µg/L. All of these cases were
required to have further testing by the Regulation. However only 20
27 Figures in ( ) brackets represent the percentage of the total population, figures in [ ] brackets represent the percentage persons above the Baseline Level.
29 Note: Because of the rounding of per cent values totals here and elsewhere in this section may not always add to 100%.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-140-
(62%) were in compliance. Of these 20, most the results of the second
sample are not considered to be so different from the first to support
the conclusion that the first sample had been tampered with (See
Appendix 3.1 for comparison of outliers). It should be noted that 12
(38%) did not provide a follow up sample as required by Law. While it
is possible for urine samples to be accidentally or deliberately
contaminated the analysis has been performed on the assumption that
the outliers reflect real exposure.
That these outliers reflect real exposure is supported by the
observation that only 7 of the levels (ranging from 1121 µg/L to 2576
µg/L) were above levels previously reported in the literature. For
example, levels of 1000 µg/L have been reported in studies of
occupational health exposures. (World Health Organisation 1991).
In addition, as noted in the Methods section of this Chapter, the
analytical techniques chosen for the analysis of this data should
minimise the effects of the outliers.
3.7.2 Data
The data analysed in this chapter represent only a small proportion of
the data routinely collected as part of the medical monitoring
undertaken to meet the requirements of Korean occupational health
and safety legislation. The data selected for analysis has concentrated
on that which provides an indication of the effectiveness of the Korean
legislative approach in minimising exposure of workers to mercury in
fluorescent lamp manufacturing companies. Some data, such as that
showing mercury in air levels in certain areas of the workplaces, while
useful for regulatory purposes, has not been analysed and presented
here. As the monitoring was undertaken at different locations in the
companies over the years, it does not necessary represent a view of air
contamination over time.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-141-
The findings did not indicate any correlation between urinary mercury
levels and blood mercury levels. This finding is supported by studies
cited in the literature review that the correlation between these
variables vary considerably and that there is a significant confounding
effect at low levels of exposure (World Health Organisation, 1991: 63).
Substantial health related data collected, as part of the medical
monitoring program, has also not been presented in this chapter. This
data has the potential to provide excellent information on the
relationship between various health effects and exposure to elemental
mercury. It may also allow other, emerging health problems to be
identified. However, as this form of investigation is outside the
objectives of this study, this data has not been analysed for
presentation here. It is important to acknowledge however that the
collection of this data could assist in the protection of the workforce
against adverse effects of exposure to mercury and other hazardous
substances by allowing health trends to be identified early and
providing evidence of the relationship between various health effects
and other variables such as mercury levels in blood and/or urine, age,
gender, general health or other personal characteristics.
However, an examination of the health and demographic data also
showed that not all of the required information is collected from all
cases on a regular basis.
3.7.3 Number of tests per annum
There are no data available on the number of mercury-exposed
workers who should undergo regular medical monitoring as required
under Korean occupational health and safety legislation. It is therefore
not possible to determine absolutely whether the 4149 workers tested
over the six year period considered by this study represents the full
population of mercury exposed workers in the six fluorescent lamp
manufacturing companies. However, an analysis of the number of
workers undergoing monitoring in each of the workplaces over the six-
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-142-
year period (Table 3.2) provides some indication of the stability of the
sample size. However, the number of urine tests undertaken per year
in each workplace (Figure 3.24) varies quite substantially.
For example, no samples were collected in Workplace C in 1994, E in
1996 and H in 1999. The total number of samples analysed each year
from 1994 to 1999 was 722, 655, 471, 829, 783 and 667 respectively.
In addition, there was a 76% increase in the total number of samples
analysed in 1997 compared with 1996. Most of this difference arises
from there being no samples analysed for Workplace E in 1996.
Although this variation may be the result of natural fluctuations in
employment levels, when considered in conjunction with the relatively
stable overall level of samples analysed per year, it is possible that the
capacity of the testing body to collect and analyse samples is more of a
deciding factor than the regulatory requirement to test all workers.
Further data on the employment levels in each workplace would be
required before the fluctuations can be explained with any certainty.
In contrast with this result it is of interest to note that an increasing
number of workers has been undergoing testing for mercury levels in
their blood at the same time as being tested for mercury levels in their
urine (Figure 3.7). In 1998 and 1999, for example, approximately 80%
of the cases were tested for both. It is noted that this testing, for
mercury levels in blood, is not required by Korean legislation but it does
aid in identifying mercury exposed workers. For example, 47 of the
434 workers found to have levels of mercury in their urine and/or blood
in excess of the Baseline Level (>100 µg/L and >3.5 µg/dL
respectively) were identified as a result of blood tests alone. These
could represent cases with recent high levels of exposure to mercury,
as blood tests are a better indicator of recent exposure whereas urine
tests provide a better indication of mercury exposure over time. The
concurrent collection of blood and urine may also negate any possible
contamination of urine specimens as very high urinary levels should be
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-143-
correlated with higher blood levels. There is much less likelihood of
accidental contamination of blood samples.
3.7.4 General trends
As noted, 10% of the workers tested over the six year period had
mercury levels in their urine, blood, or both above the Baseline Level.
This ranged from 14% in 1994 to 7.0% in 1999. This downward trend
in rates is similar to that noted in the overall trend in median levels of
mercury in urine over the same period (Figure 3.6). The finding of a
downward trend in median levels was reinforced by the finding of a
significant difference in median levels of mercury in urine over the six
year period. A 50% fall in the rate of persons with mercury in their
urine in excess of the Baseline Level is a substantial fall in occupational
health and safety terms.
The number of persons recorded as having mercury levels in their
urine in the Diagnostic Level range did not change greatly in the 6 year
period except for a large fall in 1999. It remains to be seen if this latter
trend has been able to be maintained. However on the basis of
evidence during the period of study, it is clear that a small but
unacceptable percentage of cases remain exposed to excessive levels
of mercury in their workplaces.
It should also be noted that these levels of exposure can have long
term adverse health effects.
There is also a report (Albers et al., 1988) that , as long as 20 to 35 hears after exposure, subjects who had experienced urine mercury peak levels above 600 µg per litre demonstrated significantly decreased strength, decreased coordination, increased tremor, decreased sensation, and increased prevalence of Babinski and snout reflexes when compared with control subjects (World Health Organisation, 1991: 87).
The reasons for the fall in the number of persons indicating elevated
levels of mercury in their urine with respect to either the median levels,
the Baseline Level or the Diagnostic Level in 1995 is unclear. However,
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-144-
as shown in Figure 3.13, the median level of mercury in the urine of
those tested fell in all workplaces, other than Workplaces A and G, in
1995 in comparison with 1994.
It is interesting to note that median levels of mercury in urine fell in all
workplaces, except for Workplaces C and H, between the first and last
results obtained as part of this study (Figure 3.13). Although a
preliminary review of the data presented in Table 3.4 and Figure 3.13
may suggest that much of the fall occurred as a result of the
improvement at Workplace A, a more detailed analysis shows this not
to be the case. It is known that Regulators have used the data from the
surveillance program to target specific workplaces to press for the
implementation of measures to reduce worker exposure to mercury.
Overall, the median level fell approx 11 µg/L from 28.4 µg/L (minimum
<0.1 µg/L, maximum 1773.5 µg/L) in 1994 to 17.0 µg/L (minimum 0.2
µg/L, maximum 378.4 µg/L) in 1999. However, if the results from
Workplace A are excluded the fall is very similar (approximately 10
µg/L ranging from 25.6 µg/L [minimum <0.1 µg/L, maximum 805.6
µg/L] in 1994 to 15.1 µg/L [minimum 0.2 µg/L, maximum 248.7 µg/L] in
1999).
However, the fall in recorded levels of cases at the Diagnostic Level in
1999 is largely due the fall in cases recorded in Workplace A (Figure
3.12).
Despite these encouraging results in the decrease in median levels of
mercury in urine obtained at the time of the compulsory health check-
up, and the decrease in the percentage of cases recording levels in
excess of the Baseline Level, the results still indicate a significant
exposure to inorganic mercury vapour at the fluorescent lamp
manufacturing companies.
As many of the biological concentrations of mercury were well in
excess of the Baseline Levels, which are designed to reflect the level of
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-145-
contaminants that are most likely to be observed in blood and/or urine
specimens from a worker who is exposed at the threshold limit value, it
must be assumed that many workers in Fluorescent Lamp
manufacturing companies in Korea are exposed to airborne mercury
levels well in excess of the Korean Regulatory standard of 0.05mg.m-3.
This line of reasoning is supported by the findings cited in the literature
review of the relationship between urine mercury levels and mercury in
the air commonly being in the ratio of 1-2.
3.7.5 Follow up testing
It is disturbing to note that only 44% of those persons with mercury in
their urine and/or blood in excess of the Baseline Level underwent
further testing for mercury levels in their urine and blood as required by
Korean legislation (Table 3.7). It is possible that not all persons
required to do so were able to provide both blood and urine samples.
However, 61% of those persons with mercury in their urine and/or
blood underwent further testing for mercury levels in urine and/or blood
(from Figure 3.15). The level of compliance with follow-testing as
required by Korean legislation is less than adequate.
However, a significant decrease in the median level of mercury in urine
was noted in those undergoing follow-up testing (Figure 3.16). This is
not as encouraging as it might first appear when it is noted that the
median level mercury in urine of those undergoing second tests still
remained above the Baseline Level. Further, the level of mercury in
the urine of 163 of the 252 who underwent second urine tests remained
above the Baseline Level. That is 65% of the cases who underwent
second urine tests as a result of having returned results in their first test
above the Baseline Level remained above the Baseline Level at the
time of their second test.
This suggests that relatively minor changes, if any, had been
implemented to reduce their exposure to mercury in the workplace.
However, levels of mercury in urine are an indicator of exposure over
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-146-
time and data was not available on the time between the first and
follow-up tests. Korean legislation requires that the employer take
steps to reduce the level of mercury exposure to any individual with an
elevated (above Baseline Level) of mercury in their urine or blood.
There is no requirement to remove workers from exposure.
The fall in median mercury levels in the blood of 132 workers who were
in excess of the Baseline Level at the first test and who had blood tests
on both occasions was not statistically significant. At the time of the
first test 51 of these workers had mercury levels in their blood in excess
of the Baseline Level and this number had decreased to 38 (69%) at
the time of the follow-up test.
In total, of the 263 persons who underwent second urine and/or blood
testing as a result of having biological samples above the Baseline
Level in the first test, the mercury levels remained above the Baseline
Level for 180 (68%). Slightly more encouraging is the fact that of this
263, the mercury in blood levels had dropped below the Baseline Level
in all but 69 (34%) of the 204 that had follow up blood tests. It is
possible that some improvements had been made to reduce the
exposure of 66% of the cases but that the time between tests had not
been sufficient to reduce the mercury levels in the urine enough to
bring them within the Baseline Level.
However event this figure is high and appears to confirm the
hypothesis that insufficient action had been taken in at least 34% of
cases to reduce mercury exposure levels of workers between tests.
This result is a slight improvement from the findings of Lee (1993) who
notes that 85% of the companies where workers were diagnosed with
occupational disease or symptoms no improvement’s were made in the
workplace to alleviate the conditions which caused the problem
Thus, while it is clear that mercury exposure has decreased in the
workplaces over the time of the study, there appears to be insufficient
action taken to reduce the level of exposure to mercury of workers who
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-147-
exhibit levels of absorption of inorganic mercury above the Baseline
Level. Thus, it is possible that factors other than the medical
monitoring required by Korean Legislation have been responsible for
the overall improvements noted above.
3.7.6 Regulatory requirement in terms of health surveillance
The relatively high incidence of cases with levels of mercury in their
urine and/or blood in excess of the Baseline Level and the failure to
reduce this incidence substantially by the time of the follow up test
would appear to be in contravention to the Industrial Safety and Health
Act 1996 in Korea that states:
the employer shall observe the standards for preventing the industrial accidents as prescribed by this Act ……….. and furnish to employees the information on safety and health of the workplace and safeguard the lives and maintain and promote the safety and health of employees by creating proper working environment through the improvement of working conditions and comply with the industrial accident preventive policy executed by the State (Article 5).
Employers are under an obligation of Industrial Safety and Health Act
1996 (Korea) to provide special health check-ups for their workers who
are working with hazardous conditions or materials. All special health
check-ups are undertaken by private occupational health and safety
agencies where the profit to be made from the check-ups is an
important consideration. Similarly, employers often do the minimum
required by the Industrial Safety and Health Act (1996) for the workers.
Occupational health and safety private agencies are sometimes
accused of providing only the minimum service required in order to
satisfy management concerns regarding costs. Under this
arrangement, it is possible that economic incentives may influence the
reporting or non- reporting of disease. This may also explain the low
follow up rate of testing of persons with levels of mercury in their urine
or blood in excess of the Baseline Level at the time of the first test.
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-148-
Mercury in blood is not required by legislation but urine and blood
samples were taken at the same time with the agreement of
management and unions (personal communication, Dr Choi, 16/6/03)
to overcome the difficulty and costs associated with follow up testing
within 30days when elevated mercury levels in urine are discovered.
The rational for this is not clear as the intention of the legislation is to
have persons with elevated mercury in urine levels undergo second
tests of both blood and urine to demonstrate whether mercury levels
have fallen.
This is because the biological half time of mercury is in the order of two
months and urinary excretion indicates elimination half time of about 40
days (the range of individual values being 35-90 days) (WHO, 1996).
After long-term exposure to mercury vapour, the decrease in blood
mercury can be described by two-half times: one of 2-4 days,
accounting for about 90% of the absorbed mercury, and another of 15-
30 days, accounting for most of the remainder (Burke, 1973).
Therefore the World Health Organisation suggested that mercury in
blood is a suitable indicator of recent exposure and mercury in urine is
suitable to look at cumulative exposure over previous 2-4 months.
It is also notes that at the same time as the rate of blood testing at the
time of the first test was increasing the number of persons undertaking
follow up tests as required by Regulation was also increasing. Initially
(1994) only 32% of those referred for further testing undertook the
additional tests whereas in 1999, 81% compliance was recorded. A
real benefit of undertaking blood sampling at the same time as the
urine sampling is that it provides some information that may help to
identify whether or not the urine samples have become contaminated.
3.8 Summary
This survey did not cover symptoms, work practices including previous
employment, hours of work, past and current job tasks and use of the
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-149-
workers’ compensation due to the lack of appropriate data to analyse.
The study focused on the trend of mercury levels in worker’s biological
samples over past 6 years. This study did not include a control, or non-
exposed, group for comparison.
Due to the focus on mercury workers and extensive efforts to build up
quantitative individual exposure measurement, this study affords a
unique opportunity to obtain a better understanding of exposure risk
among workers in the lamp manufacturing companies in Korea.
The urine mercury levels indicate substantial absorption of mercury
among mercury process workers at the fluorescent lamp manufacturing
companies. In the period 1994-1999, of the samples collected from
exposed workers at the time of their Special Medial Exam, 10%
exceeded the Baseline Level set by Regulation. In addition, there were
81 cases at the Diagnostic Level in the same period. However there
was a significant reduction in the median levels of mercury in the urine
of workers over the study period and a substantial fall in the percentage
of workers with levels of mercury in their urine or blood in excess of the
Baseline Levels.
However, the failure to adequately decrease the levels of mercury in
the blood of 34% of persons with elevated exposures at the first
screening test indicates a failure by employers to adequately protect at
risk workers from the adverse effects of mercury exposure. No
significant rate of improvement was noted over the study period.
On the other hand a substantial improvement in the biological levels of
mercury exposed workers at one workplace with very poor
performance at the beginning of the period is noted.
Thus, despite the limitations of this study, it is the first to demonstrate
an association between mercury exposure and the requirements to
undertake health surveillance of occupationally exposed persons. The
association cannot be shown to be a causal one. How the observation
Mercury exposure in fluorescent lamp manufacturing companies in Korea
-150-
that much of the improvement has come about because of
improvements in managing mercury exposure in one workplace and
the knowledge that much of this improvement came about as a result
of pressure by the Regulator based on the information from the health
surveillance programme supports the hypothesis that such a causal
relationship may exist.
It is not possible to draw any firm conclusions regarding the efficacy of
the testing regimen with respect to the number of exposed workers
undergoing special health check-ups, including biological monitoring,
except to note that the numbers fluctuate widely on an annual basis
with workers in some workplaces not receiving any biological
monitoring in some years. The follow-up monitoring required when
mercury levels exceed Baseline Levels has improved substantially over
the 6 year time period.
A further problem of the surveillance system of occupational health in
Korea is the lack of close connection between using air monitoring data
and biological data in occupational health surveillance system. There
is also a lack of assessment and follow up of the management of the
workers’ exposures and improvements in workplace conditions. The
effectiveness of the occupational health and safety services is therefore
decreased, even though they have expended a lot of effort in the
occupational health and safety area over the past 30 years.
A considerable increase in the quantity and quality of exposure data in
the work environment will be required to allow more reliable
epidemiological studies in 10 or 20 years. It seems impossible to
obtain this easily for the whole of industry because most industries in
the world cannot be expected to finance a program going far beyond
what is legally required. Therefore governments and/or international
bodies should support this long-term effort.
-151-
Mercury exposure in dental workers in Queensland
4.1 Background
Much attention is being focused upon the issue of mercury exposure
from dental amalgam restorations and the potential for adverse health
effects (Reinhardt, 1987).This controversy has grown beyond the
confines of the dental profession itself and is becoming an emotional
public issue. Dental staff are being challenged to prove the safety of
amalgams. Relatively few studies of mercury exposure in dental staff
in Australia have been conducted.
Industry as a whole, including health care, is being driven to use
alternative products and technology to reduce the manufacture and
consumption of mercury. Additionally, governments worldwide are
being lobbied by the environmental movement to tighten or introduce
legislative requirements concerning mercury and its use (Safety and
Security Service Department. Royal Brisbane Hospital and Health
Service District, 2000). As most people are aware, mercury is a
component used in dental amalgams. Mercury containing dental
amalgam is still widely preferred restorative material in the dental
industry in Australia (Safety and Security Service Department. Royal
Brisbane Hospital and Health Service District, 2000). As a
consequence of the continuing use of dental mercury, dental
practitioners and dental care workers continue to express occupational
health and safety concerns relating to work practices associated with
the use of this hazardous substances.
4
Mercury exposure in dental workers in Queensland
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This case study involved 60 dental staff selected on a voluntary basis
for an Oral Health Service in Queensland, Australia. It involved both a
unexposed and exposed group. Volunteers participated in either or
both biological monitoring for mercury and completed a self-
administered questionnaire survey investigating their knowledge of the
adverse effects of mercury exposure and the health and safety
management of mercury in the workplace. The study also involved
environmental monitoring for airborne mercury concentrations in the
workplaces of participants. Data were collected between Mar 2000
and Dec 2001.
This study investigates the extent of mercury exposure, and concerns
about, and perception of, mercury exposure among dental staff of the
oral health service. Finally brief recommendations are made for
managing mercury exposure with respect to legislative requirements
and management systems.
4.2 Introduction
The toxicology of, and exposure to, mercury was discussed extensively
in Chapter 2. The following is a summary of some of the points raised
in that Chapter.
Amalgam containing mercury is still widely used in dental procedures
and remains a hazard for dental staff. Amalgam or silver filling contains
a mixture of metals such as silver, copper and tin in addition to
mercury, which chemically binds these components into a hard, stable
and safe substance (Dental Amalgam: 150 Years of Safety and
Effectiveness, 2000).
The issues relating to mercury use in the manufacturing industry and
the debate about mercury exposure and dental workers has been long
running. Amalgam has today been questioned both as a potential
health risk factor for all individuals with amalgam restorations and as an
Mercury exposure in dental workers in Queensland
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occupational risk for dental personnel (Skare & Bergstrom, 1990).
Most dental staff are exposed daily to mercury, in particular elemental
mercury vapour (Hg0), by handling dental silver `amalgam (Schuurs,
1999) and through activities such as storing of mercury, the mixing of
amalgam, the removal and insertion of amalgam restorations and the
handling of spillage (Skare & Bergstrom, 1990). These hazards are in
addition to the others faced as part of their work including the sedentary
nature of their work, ionising radiation, inhalation of anaesthesia,
grinding dust, infectious agents and stress (McComb, 1997).
Some protection against these hazards is intended to be provided by
legislative arrangements and these have been outlined in the literature
review. In summary, according to Queensland legislative
requirements, employers have an obligation under the Workplace
Health and Safety Act 1995 (Qld) to ensure health and safety at the
workplace. This performance-based style of legislation imposes an
overarching requirement on employers that they provide a safe and
healthy workplace for their employees (Gunningham & Johnstone,
1999). It does not tell employers what to do achieve this outcome;
instead it concentrates on the outcome to be achieved.
The biological exposure indices established for mercury in Queensland
were discussed in detail in Chapter 2. (Table 4.1)
Table 4.1: Biological exposure indices for mercury
Variables Baseline level Action level Removal level Hg in Urine (µg/g creatinine)
Less than 50 Greater than 50 Greater than 100
There is some debate about the risk to dental staff and patients from
amalgam fillings.
While there is no doubt that mercury is toxic, there is no strong evidence to show that carefully prepared and placed amalgams pose any risk to dental patiens or dental personnel. However, in
Mercury exposure in dental workers in Queensland
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assessing the safety of dental personnel we need to look at all the available evidence (Eley & Cox, 1993).
There is little doubt that unless properly controlled the use of amalgam
in dental practices can expose dental workers to elevated levels of
mercury.
4.3 Methods
4.3.1 Recruitment of study subjects
The study group was drawn from a Queensland Oral Health Service,
which employs approximately 280 persons including 50 dentists 30
dental therapists, and 65 dental assistants. Staff of the Oral Health
Service were asked to participate as volunteers for this study via mail
outs, which included an information package and volunteer form (See
Appendix 4.1) to indicate their preparedness to be involved and the
extent to which they were prepared to be involved. The volunteer form
had 5 options for people prepared to participate in the study. They
were able to limit their involvement to any or all of:
1) the completion of a questionnaire surveys;
2) interview;
3) job analysis;
4) blood sampling; and/or
5) urine sampling.
The study population volunteers were informed about dental amalgam
exposures in dental work and of the study by one of the research team
members during their annual training sessions in November 2000. The
information about dental amalgam exposures in dental work is not
considered to have biased this study as the information provided is part
of the usual annual training session.
Mercury exposure in dental workers in Queensland
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Sixty two (62) persons agreed to participate in the study. Sixty (60) of
these were eligible according to the selection criteria outlined below.
All of the eligible participants agreed to participate in the questionnaire
survey and 58 of the eligible volunteers agreed to participate in
providing a urine sample for biological monitoring. A diagrammatic
representation of the selection process is shown in Figure 4.1.
The services of the Oral Health Service fall into four categories:
Category 1 Children's hospital
Provides secondary and tertiary levels of oral treatment such as, oro-
facial surgery under general anaesthesia.
Category 2 School dental program
Provides primary health care treatment including fillings and extraction
of teeth.
Presentations to 280 Oral Health Service staff at annual training session.
60 volunteers
Children’s Hospital 1q, 13b
School Dental
Program 1q, 14b
Community Oral Health
Program 19b
Dental Hospital
12b
Information package, volunteer and consent forms mailed to 280 Oral Health
Service Staff
Unexposed
b=agreed to complete questionnaire & provide urine sample q=agreed to complete questionnaire only
Figure 4.1: Recruitment process for study participants
Mercury exposure in dental workers in Queensland
-156-
Category 3 Community Oral Health Program (COHP)
Clients are generally welfare recipients treated in fixed health clinics in
a metropolitan region.
Category 4 Dental Hospital
This is a University Teaching Hospital which acts as a tertiary referral
centre where patients are seen by dental staff, undergraduate and
postgraduate students.
Workers in each of these services perform different work and have
different exposures to mercury. Category 1 has minimal or no
exposure to mercury and were therefore served as the unexposed
group. Mercury exposure was possible within the remaining
Categories and workers drawn from these establishments served as
the exposed group.
Of the 58 persons who agreed to participate in the biological monitoring
components of the study, there were 45 in the exposed group and 13 in
the unexposed group.
The following criteria were used in the final selection of unexposed and
exposed subjects:
1) The exposed workers should have been exposed to mercury for
at least 6 months and should not have been exposed to large
amount of mercury prior to the survey.
2) There should be no medical history in the unexposed or
exposed workers of neurological, psychiatric, or renal disorder.
4.3.2 Self-administered questionnaire survey
A simplified PRECEDE-PROCEED model (Green & Kreuter, 1999) is
used in this study. This model is multidimensional and founded in
social/behavioural science, epidemiology, administration and
Mercury exposure in dental workers in Queensland
-157-
education. As such, it recognizes that health and health behaviours
have multiple causations, which must be evaluated in order to assure
appropriate intervention. This model assumes three factors:
Predisposing factors, which are motivational antecedents to behaviour;
Enabling factors, which enable the motivation to be realised; and
Reinforcing factors, which provide an incentive for a continuation of the behaviour (Green & Kreuter, 1999).
At the worker level in this study,
Predisposing factors include awareness, attitudes, and knowledge, risk
perception and risk taking behaviour;
Enabling factors include training, the availability of control measures
such as personal protective equipment (PPE) and the role of safety
committees in empowering workers; and
Reinforcing factors include management's attitudes and enforcement of
safety conditions, management's support for safe work practice and
equipment.
The survey sought information on the following;
3) Demographics and health data.
4) Health and safety attitude and knowledge of supervisors and
employees.
5) Knowledge of any occupational health and safety system in
place to manage mercury exposure.
The questionnaire was designed and piloted among 8 dental staff from
a separate Oral Health Service. The questionnaire was designed to
establish occupational health and safety knowledge, attitudes, and
identify any management system in place. This pilot study was
Mercury exposure in dental workers in Queensland
-158-
evaluated by looking at the items in the survey in terms of item quantity
and overall validity and reliability.
The results of this pilot study and comments received from these
participants were used to amend the questionnaire that was
administered to the Oral Health Service staff who agreed to participate
in the study. A copy of the questionnaire is included in Appendix 4.3.
The result of this study is used, in part, to identify mercury exposure
level in subjects’ urine samples from long-term, low-dose mercury
(amalgam) exposure. The questionnaire was designed to allow
collection of some data that could be used for the comparison with
Korean Fluorescent lamp manufacturing workers.
4.3.3 Air monitoring
4.3.3.1 Monitoring Methods
At present, Australia has no guidelines available on the number of
samples that should be collected for occupational hygiene monitoring.
One rule of thumb that some occupational hygienists use is that an
occupational hygienist can deal with 5 or 10 sampling trains at once.
It follows that a group of 5-10 samples collected would be appropriate.
However, this does not consider different workforce sizes. The U.S.
National Institute of Occupational Safety and Health (NIOSH) has
suggested a method that can be used to select the number of workers
to be monitored, given a certain level of confidence. NIOSH
recommends that sufficient samples should be taken, to be reasonably
confident (e.g. 90% confident) that at least one person in the top group
of all exposures in the cohort has been sampled (Lee, 1987; Brazier &
Waite, 2003; Tranter, 1999).
In order to obtain a reliable estimate of airborne mercury
concentrations in the workplaces a Jerome 431-X mercury vapour
analyser was used.
Mercury exposure in dental workers in Queensland
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The Jerome 431-X mercury vapour analyser uses a patented gold film sensor for accurate detection and measurement of toxic mercury vapour in the air. This portable hand-held unit can easily be carried to locations with mercury concerns for applications such as industrial hygiene monitoring, mercury spill clean up and mercury exclusion testing. Simple, push-button operation allows users to measure mercury levels from 0.003 to 0.999 mg/m3 in just seconds (Arizona Instrument Corporation, c1992).
This method of monitoring overcomes many of the limitations relating to
sample numbers discussed above as the monitoring is, in effect, a
continual process. Samples were taken in areas considered to be high
risk for mercury contamination. The rationale for the selection of these
areas is discussed below.
4.3.3.2 Air monitoring locations
The methodology utilised during this survey was to monitor the level of
mercury vapour in typical areas that were likely to or had the potential
to produce elevated readings according to a previous Oral Health
Service air monitoring report in May 2000.
The same monitoring rationale and locations were chosen for this
study. Details of specific locations that were tested and the rational for
choosing these locations, as noted in the above report, are as follows;
1. Around the base of dental chairs
There is significant manual handling and application of dental amalgam in the vicinity of the dental chair, the potential for spillages is significant. In some locations dental chairs may have been in operation for a long period of time, therefore the likelihood of split mercury accumulation can be increased.
During the monitoring process the mercury vapour analyser was continually manoeuvred around the chair base paying particular attention to where it meets the floor and the mechanical components under the chair including crevasses and voids that could trap foreign matter.
2. Amalgam preparation area
The amalgam preparation area contains several areas and processes that have potential to promote or contribute to mercury vapour levels within the dental care workplace. These include;
• The amalgam capsule storage area
• The amalgam-oscillating mixer
• Equipment draws containing amalgam application equipment
Mercury exposure in dental workers in Queensland
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• Preparation bench tops
The mercury vapour analyser was continually moved around the above locations to identify any potential sources.
3. Spittoons
During and after amalgam procedures patients perform routine mouth rinses and discharge into the spittoon. Within the spittoons’ plumbing pipe work is a waste trap, which prevents products such as waste amalgam entering the drainage system. Depending on the frequency this waste trap is cleaned or replaced, amalgam can accumulate in the trap and be a potential vapour source.
4. Waste amalgam store areas
Waste amalgam that is not used in a dental procedure and/or amalgam excess to procedural requirements is stored in a variety of different receptacles. These receptacles contain either water or affixer as an encapsulating medium. Due to the variety of receptacles used for this purpose, i.e. Glass and plastic of varying qualities, there is potential breakages and subsequent spillages. The majority of these receptacles are stored in under bench cupboards where there are other products stored. The process used for testing these locations was to open the store area and take a sample from the atmosphere above and around the location of the waste amalgam container.
5. Miscellaneous tests
Various other locations such as pedestrian access routes, dental equipment, general work environments and cleaning equipment storage area and waste box were also monitored [(Safety and Security Service Department. Royal Brisbane Hospital and Health Service District, 2000).
In addition, the previous study had shown low levels of mercury
throughout the working environment and it was therefore decided that a
more rigorous monitoring regime, designed to identify worst case
exposures was necessary. If high levels of mercury contamination was
found in these locations representative monitoring could then be
undertaken to estimate exposure levels.
The concentrations of mercury vapour in the dental surgeries were
measured with a Jerome 431-X gold film mercury vapour analyser.
Any other locations identified as being potential sources of mercury
exposure during the survey were also monitored. All air monitoring
was conducted as close as possible to areas of possible mercury
contamination. The aim was to detect areas of poor housekeeping
which could result in mercury exposure to workers in the workplaces.
Mercury exposure in dental workers in Queensland
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Following the criteria established above, environmental monitoring for
airborne mercury concentrations was undertaken in 14 randomly
selected workplaces: 11 school and community based dental health
clinics and 3 mobile dental vans. In total, measurements were taken in
179 separate locations. Twenty nine (29) of the measurements were
taken in the workplace occupied by the unexposed group (Children’s
Dental Hospital). At each location the highest concentration monitored
has been recorded. These results are presented in full in Appendix 4.2
4.3.4 Biological monitoring
For biological monitoring of mercury exposure, mercury concentration
in whole blood and urine are the most important parameters (Foa,
1986; Clarkson, Friberg et al., 1988; Lauwerys & Hoet, 1993). Many
previous studies have reported that data on urinary mercury are the
best predictors of exposure to mercury and are reasonable predictors
of exposure to mercury in the dental services area (Symanski, Sallsten
et al., 2000; Berlin, 1986).
Mercury in urine tends to reflect cumulative exposure over the previous
2-4 months, while mercury in blood indicates recent exposure (Foa,
1986; Clarkson, Friberg et al., 1988; Lauwerys & Hoet, 1993).
Subjects were asked to provide a sample of urine in the morning at the
end of a working week and store it in a freezer immediately after taken
until the day of collection (up to 1 week after the urine sample container
was provided). The morning urine samples were collected at home by
each subject in 250ml acid-washed polyethylene bottles. Samples
were taken by the researcher for analysis to the National Research
Centre for Environmental Toxicology in Queensland. Analysis was
conducted by cold vapour atomic absorption spectroscopy (CV-AAS).
The creatinine levels of any samples with results above the detectable
level of 0.01µg/ml of urine were determined and results expressed in
relation to creatinine content to take into account the concentration of a
person’s urine.
Mercury exposure in dental workers in Queensland
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This method for the determination of total mercury in biological tissues
is the most widely used method and is based on a technique
elaborated in detail by Hatch and Ott (1968). In this method, (divalent)
ionic mercury is reduced to its metallic form (Hgo) in acidic solution
using a powerful reducing agent. Subsequently, the elemental mercury
is volatilized (purged) by a carrier gas and transported into an
absorption cell, where the 253.65 nm wavelength absorbance of
mercury atoms is measured.
The method used for the sampling, storage and analysis of urine for
mercury concentration in urine is a standard method recommended by
the World Health Organisation (1976).
As noted in the following section of this paper, there was no significant
level found in the urine samples. Therefore, blood samples were not
collected for analysis. Similarly, sufficient information was obtained
from the questionnaire survey, interviews, and job analyses with
participants were not considered necessary.
4.3.5 Data analysis
Data was entered in SPSS (Version 10.1.0) for Windows for advanced
data analysis. Continuous data obtained from the questionnaire survey
was analysed for normality to ensure its suitability for analysis using
standard univariate analysis. Standard univariate statistics have been
used to determine variable associations between the unexposed and
exposed group.
Unless otherwise noted, significance was set at a two-tail ρ value of
0.05.
Categorical data obtained from the questionnaire survey was explored
with respect to adequate representation within each category and,
where necessary, categories were combined. Associations between
the unexposed and exposed group were analysed using Chi-Squared
Mercury exposure in dental workers in Queensland
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Analysis and where the sample size in 2x2 tables resulted in expected
values of <5 the Fischer’s Exact Test was used. These instances are
noted in the text.
Descriptive statistics were used to describe work practices when
working with mercury amalgam. In this instance the work practices of
the exposed group only were analysed as the unexposed group did not
work with mercury. Knowledge of, and general occupational health
and safety working practices are reported using descriptive statistics for
the participants as a whole. However any associations between the
exposed and unexposed group with respect to these issues were
examined as described above.
Mercury exposure data obtained from urine analysis was analysed in a
similar manner to that described for the data from the questionnaire
survey above. Associations between mercury exposure and relevant
variables such as the number of amalgam fillings, non-occupational
exposures, hours of work, and various hygiene factors were examined
using bivariate correlation analysis and, where appropriate, Chi-
Squared analysis.
4.4 Results
4.4.1 Demographic characteristics
4.4.1.1 Questionnaire survey
A copy of the full data set is contained in Appendix 4.4.
4.4.1.1.1 Volunteers vs. Participants
Forty-five (45) of the eligible volunteers completed and returned the
questionnaire. Most completed all of the questions. Completed
questionnaires were not received from 15 of those who initially agreed
to participate in the survey. Table 4.2 indicates the workplace and
Mercury exposure in dental workers in Queensland
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gender of the participants against those who initially volunteered to
participate.
Table 4.2: Workplaces of volunteers and participants in questionnaire survey29
Workplace Children’s Hospital %(n)30
School Dental Program %(n)
Community Oral Health %(n)
Dental Hospital. %(n)
Volunteers (n=60) 23%(14) 25%(15) 32%(19) 20%(12) Participants (n=45) 18%(8) 27%(12) 38%(17) 18%(8)
A breakdown of the gender of volunteers and participants in the
exposed and unexposed groups is provided in Table 4.3.
Table 4.3: Gender of volunteers and participants in questionnaire survey
Exposed Group %(n) Unexposed Group %(n) Gender Males Females Males Females Volunteers (n=60) 23%(14) 53%(32) 10%(6) 13%(8) Participants (n=45) 27%(12) 55%(25) 9%(4) 9%(4)
Chi-Square analysis was used to investigate the relationship between
the volunteers and the actual participants in the questionnaire survey.
Of the volunteers for the questionnaire survey, 23% were from the
unexposed group, and 77% were from the exposed group. Of the
participants 18% were from the unexposed group and 82% were from
the exposed group. No statistically significant difference was found in
the proportion the volunteers who were in the unexposed or exposed
group and the proportion of participants from these two groups
(c2[1]=0.5, ρ=0.479).
Similarly, no statistically significant difference (Chi-Square Test,
c2[3]=0.8, ρ=0.861) was found in the proportion of volunteers and
participants in the questionnaire survey from each of the workplaces.
Nor was any statistically significant difference (Chi-Square Test,
30 The participants from the Children’s Hospital formed the control group.
Mercury exposure in dental workers in Queensland
-165-
c2[1]=0.1, ρ=0.812) found in the gender relationship between
volunteers and participants.
4.4.1.1.2 Exposed Group vs. Unexposed Group
The respondents included 37 from the exposed group and 8 from the
unexposed group and included 16 dentists, 10 dental assistants, 6
dental technician and 13 dental therapists. Most of the participants are
non-smokers and have less than 10 amalgam fillings in their mouth.
A breakdown of the demographic characteristics of the exposed and
unexposed groups is presented in Table 4.4.
Mercury exposure in dental workers in Queensland
-166-
Table 4.4: Demographics of subjects completing questionnaire
Variables Unexposed group (N=8) No. (%)
Exposed group (N=37) No. (%)
Gender Female (n=29) 4 (50.0) 25 (67.6) Male (n=16) 4 (50.0) 12 (32.4) Age <30 (n=4) 1 (12.5) 3 (8.1) 30-<40 (n=15) 4 (50.0) 11 (29.7) 40-<50 (n=18) 3 (37.5) 15 (40.5) ≥50 (n=8) 0 (0.0) 8 (21.6)
Mean Age (±SD) 36.4±8.2 42.9±9.7 Total years of working in the Oral Health Service ≤4 yrs (n=10) 2 (25.0) 8 (21.6) >4-8 yrs (n=10) 3 (37.5) 7 (18.9) >8-12 yrs (n=10) 3 (37.5) 7 (18.9) >12-24 yrs (n=11) 0 (0.0) 11 (29.7) >24 yrs (n=4) 0 (0.0) 4 (10.8)
Mean years of service (±SD) 7.0±3.2 16.0±21.7 Education achievement TAFE (n=25) 5 (62.5) 20 (54.1) Undergraduate- (n=20) 3 (37.5) 17 (45.9) Smoking status Non-smoker (n=34) 6 (75.0) 28 (75.7) Ex-smoker (n=8) 1 (12.5) 7 (18.9) Current smoker (n=3) 1 (12.5) 2 (5.4) Working habits No. of average days work per month (±SD) 18.50±0.92 18.43±5.33
No. of average hours per month (±SD) 151.0±2.82 142.6±35.6 Occupation Dentist (n=16) 3 (37.5) 13 (35.1) Dental Assistant (n=10) 3 (37.5) 7 (18.9) Dental Technician (n=6) 2 (25.0) 4 (10.8) Dental Therapist (n=13) 0 (0.0) 13 (35.1)
The average age for the male and female participants was 45.5 years
and 40 years respectively, and ranged from 28 to 69 years for males
and 25 to 58 years for females. An independent-samples t-test was
conducted to compare ages of the exposed and unexposed groups.
There was no statistically significant difference in the age of the
exposed group (mean=42.9, SD=9.7), and the unexposed group
(mean=36.4, SD=8.2; t[43]=1.8, ρ=0.086). It is noted that the age
distributions are different (Table 4.4), however the small numbers in the
unexposed group prevented any statistical analysis of this difference.
Mercury exposure in dental workers in Queensland
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No statistically significant difference was found in the Years of Service
of the exposed group (mean=16.0, SD=21.7), and the unexposed
group (mean=7.0, SD=3.2; t[43]=1.2, ρ=0.252) or of the days or hours
worked per month by the exposed group (mean=18.4, SD=5.3 and
mean=142.6, SD=35.6 respectively) and the unexposed group
(mean=18.5, SD=0.93; t[43]=-0.0, ρ=0.972 and mean=151.0, SD=2.8;
t[37.97]=-1.4, ρ=0.168 respectively) when tested using an independent
samples t-test.
No statistically significant difference was found in the proportion of
males and females in the exposed and unexposed groups using the
Fisher’s Exact Test (c2[1]=0.9, ρ [2-sided]=0.427, ρ [1-sided]=0.291).
An independent-samples t-test was used to compare the number of
amalgam fillings in the mouths of subjects in the unexposed group and
the exposed group. No statistically significant difference was found in
the number of amalgam fillings in the mouths of subjects in the
unexposed group (mean=8.0, SD=4.8) and those in the mouths of
subjects in the exposed group (mean=6.8, SD=5.2; t[39]=-0.5,
ρ=0.602).
Of the participants 45% (n=20) were university graduated, and 4%
(n=2) had a high school degree or less. Approximately half of
participants (51%, n=23) had some TAFE or college training. Most of
participants (96%, n=43) had TAFE or tertiary education. No
statistically significant difference was found in the proportion of subjects
with TAFE education or less and tertiary education in the exposed or
unexposed groups using the Fisher’s Exact Test (c2[1]=0.2, ρ [2-
sided]=0.716 and ρ [1-sided]=0.487).
4.4.1.1.3 Gender characteristics
As already noted, there was no statistically significant difference in the
proportion of males and females in the exposed and unexposed
Mercury exposure in dental workers in Queensland
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groups, however a number of differences were noted between the
gender groups.
An independent-samples t-test was conducted to compare ages of
males and females. There was no statistically significant difference in
the age of males (mean=45.6, SD=12.1), and females (mean=39.6,
SD=7.5; t[21.6]=1.8, ρ=0.086). There was however a statistically
significant difference in the hours worked per month of males
(mean=155.6, SD=6.9), and females (mean=137.8, SD=38.8;
t[31.2]=2.4, ρ=0.023).
The number of males and females by occupation group is shown in
Table 4.5.
Table 4.5: Occupation groups of survey participants by gender
Occupation Dentists %(n) Dental Assistants %(n)
Dental Technicians %(n)
Dental Therapists %(n)
Male (n=16) 69%(11) 0%(0) 19%(3) 12%(2) Female (n=29) 17%(5) 34%(10) 10%(3) 38%(11)
The data on occupation was regrouped into two groups, dental
assistants and dental therapists in one group and dentists and dental
technicians in the other for analysis. Gender was strongly correlated
with the occupation groups dentists or dental technicians, and dental
assistants or dental therapists (Chi-Squared Test, c2[1]=17.1,
ρ=<0.0005). Males formed 63% (n=14) of dentists and dental
technicians and females formed 91% (n=21) of dental assistants and
dental therapists.
Gender was also strongly correlated with education (Chi-Squared Test,
c2[1]=13.6, ρ=<0.0005). A university education was reported by 81%
(n=13) of males 24% (n=7) of females. A TAFE education or less was
reported by the remainder.
Mercury exposure in dental workers in Queensland
-169-
4.4.1.2 Mercury management in the workplace
The Fisher’s Exact Test was used to analyse participants' knowledge
with respect to the way in which mercury can enter the body. In this
case study there was a significant association (c2[1]=10.2, ρ [1-
sided]=0.003, ρ [2-sided]=0.003) between membership of the
unexposed or exposed group and knowledge of the way in which they
could be exposed to mercury amalgam. The exposed group were
more likely to be aware that mercury vapour could enter the respiratory
system than the unexposed group (Figure 4.2).
73
13
01020304050607080
Perc
enta
ge
Yes"Mercury amalgam can be vaporised and
enter the respiratory system"
Experimental Control
Figure 4.2: Knowledge of mercury exposure across groups
Similarly, there was a strong trend but not a statistically significant
difference (Fishers Exact Test c2[1]=4.5, ρ [1-sided]=0.049, ρ [2-
sided]=0.085) in the proportion of the unexposed and exposed group
who had considered that working with amalgam could influence their
health. The exposed group were more likely than the unexposed
group to have considered this possibility (Figure 4.3).
Mercury exposure in dental workers in Queensland
-170-
76
38
01020304050607080
Perc
enta
ge
Yes"Considered that exposure to amalgam could
endanger my health"
unexposed exposed
Figure 4.3: Amalgam and health across groups
Of the exposed group, 51% (n=19) of the respondents indicated that a
risk assessment for mercury had been completed in their workplace;
16% (n=6) reported that no risk assessment had been conducted and
32% (n=12) were unsure31.
Thirty five per cent (35%, n=13) of the exposed group reported that
they had received a copy of the risk assessment report. The majority
(95%, n=35) of the exposed group reported that they wore personal
protective equipment when working with mercury.
The three questions regarding the participants’ knowledge of the way in
which mercury amalgam enters the body, participants’ consideration of
possible health implications of working with mercury amalgam, and the
wearing of personal protective equipment were also analysed with
respect to gender and occupation for the exposed group only. Further
analysis of the unexposed group’s response was not considered
relevant as they do not work with mercury.
Small sample size prevented statistical analysis of many of these
relationships but a trend was noted in the proportion of various 31 This latter group includes 1 of the exposed group who did not answer this question.
Mercury exposure in dental workers in Queensland
-171-
occupation groups which were aware of the way in which mercury
amalgam could enter the body. Dentists and dental therapists (86%,
n=14 and 85%, n=11 respectively) were more likely to be aware that
mercury amalgam could be vaporised and enter the respiratory system
than were dental assistants and dental technicians (57%, n=6 and
25%, n=2 respectively) (Table 4.6).
Table 4.6: Awareness of mercury absorption by occupation group
Do you believe that mercury amalgam can be vaporised and enter the respiratory system? Occupation No Yes Don’t know
Dentist (n=13) 15% 85% 0% Dental assistant (n=7) 14% 57% 29% Dental technician (n=4) 25% 25% 50% Dental therapist (n=13) 8% 85% 8%32
As noted earlier, the percentage of the exposed group who reported
wearing personal protective equipment when working with amalgam
was high (95%, n=35). It is noted that the two persons who reported
not wearing personal protective equipment were both dental
technicians.
Table 4.7: Wearing of personal protective equipment by occupation
Do you regularly were personal protective equipment while you are working amalgam or mercury? Occupation No Yes Dentist (n=13) 0 100% Dental assistant (n=7) 0 100% Dental technician (n=4) 50% 50% Dental therapist (n=13) 0 100%
Within the exposed group, information on the safe use of amalgam at
work was more likely to have been received by dentists (85%, n=11)
and dental therapists (92%, n=12) than by dental assistants (57%, n=4)
or dental technicians (50%, n=2) (Table 4.8).
32 Note: In this and other instances where results have been rounded to the nearest per cent, totals may add to slightly more or less than 100%.
Mercury exposure in dental workers in Queensland
-172-
Table 4.8: Receipt of information on the safe use of amalgam at work across occupation groups
Have you ever received information on the safe use of amalgam at work? Occupation group Yes %(n) No %(n) Don’t know %(n) Dentist (n=13) 85%(11) 15%(2) 0 Dental assistant (n=7) 57%(4) 29%(2) 14%(1) Dental technician (n=4) 50%(2) 50%(2) 0 Dental therapist (n=13) 92%(12) 8%(1) 0
This data was regrouped to allow analysis of those who received
information with those who answered “no” or “don’t know” and to allow
comparison of dentists and dental therapists as a group with the
grouping of dental assistants and dental technicians. When analysed
using Fisher’s Exact Test, there was a significant correlation (c2[1]=5.3,
ρ [2-sided]=0.035, ρ [1-sided]=0.035) between the receipt of
information and being a member of one of the groups comprising
dentists and dental therapists, or dental assistants and dental
technicians (Figure 4.4).
90
38
0102030405060708090
Perc
enta
ge
Yes
"Have you ever received information on the safe use of amalgam at work?"
Dentists and Dental Therapists
Dental Assistants and DentalTechnicians
Figure 4.4: Receipt of information across occupation groups
It is also noted that, within the exposed group, while 100% (n=16) of
males reported having received information on the safe use of
Mercury exposure in dental workers in Queensland
-173-
amalgam at work, only 68% (n=18) of females reported having
received this information. When analysed using Fisher’s Exact Test,
there was a significant correlation between gender and those who
reported having received this information (c2[1]=4.9, ρ [2-sided]=0.036,
ρ [1-sided]=0.028) (Figure 4.5).
100
68
0102030405060708090
100
Perc
enta
ge
Yes"Have you ever received information on
the safe use of amalgam at work?"
MalesFemales
Figure 4.5: Receipt of information across gender groups
Of the exposed group, 43% (n=16) indicated that they thought that the
management of mercury in the workplace effectively prevented
exposure. 24% (n=9) indicated the workplace exposure was not
adequately prevented. The proportion of persons who indicated that
exposure was adequately prevented did not differ significantly for age
group, workplace, gender, or occupation when analysed using
correlation analysis or, where appropriate, Chi-Square Analysis.
There was a significant correlation between having a position
description which clearly described workplace health and safety
responsibilities and views on the management of mercury effectively
preventing exposure (Chi-Squared Test, c2[1]=6.3, ρ=0.012) (Figure
4.6).
Mercury exposure in dental workers in Queensland
-174-
70
35
0
10
20
30
40
50
60
70
Per
cent
age
Mercury exposure is controlled
OHS responsibilitiesclearly definedOHS Responsibilities notdefined/Don't know
Figure 4.6: Relationship between position description and control of mercury exposure
There was also a significant positive association between having a
formal feedback system in place and opinions the management of
mercury effectively prevented exposure (Chi-Squared Test, c2[1]=8.4,
ρ=0.004) (Figure 4.7).
67
12
0
10
20
30
40
50
60
70
Perc
enta
ge
Mercury exposure is controlled
Formal feedback system inplaceNo formal feedbacksystem/Don't know
Figure 4.7: Relationship between feedback system and control of mercury exposure
Mercury exposure in dental workers in Queensland
-175-
4.4.1.3 Occupational health & safety management in the workplace
In general there was a high awareness of occupational health and
safety management issues in the workplace. For example:
Eighty nine per cent (89%, n=40) of respondents (n=45) were
aware of occupational health and safety programs in their
workplace;
Eighty eight per cent (88%, n=39) of respondents (n=44)
indicated that there was a Workplace Health and Safety Officer
or Representative in their work area;
Eighty per cent (80%, n=36) of respondents (n=45) were aware
of the existence of health and safety legislation to protect them
from health and safety hazards while at work;
Eighty nine percent (89%, n=38) of respondents (n=43)
indicated that they were aware of their obligations under the
Workplace Health and Safety Act; and
Ninety one per cent (91%, n=41) of respondents (n=45) were
aware of formal procedures to report health and safety hazards,
etc. to management.
The following results concentrate on those instances where responses
were less homogeneous.
4.4.1.3.1 Training
A number of questions in the survey explored occupational health and
safety training. Responses to these questions are presented in Table
4.9.
Mercury exposure in dental workers in Queensland
-176-
Table 4.9: Workplace health and safety training
Question Yes %(n)
No %(n)
Don’t know %(n)
Do you know who is responsible for conducting health & safety training in your workplace? (n=45)
53%(24) 47%(21)33
Have you undertaken occupational health and safety training? (n=43)
26%(11) 74%(32)
Are all site employees, including managers and supervisors, provided with health and safety training? (n=44)
52%(23) 18%(8) 30%(13)
When tested using Chi-Squared Analysis and, where appropriate
correlation analysis, no significant association was found between
relevant variables and the training related questions outlined above. It
is noted however, that 50% (n=8) of respondents in the community oral
health program have undertaken occupational health and safety
training whereas 13% (n=2), 0%, and 17% (n=2) of respondents in the
dental hospital, children’s hospital and school dental program
respectively had undertaken training (Figure 4.8).
88
13
50 50
100
83
17
0102030405060708090
100
Perc
enta
ge
DentalHospital
CommunityOral Health
Program
Children'sHospital
SchoolDental
Program
No OHS training Have undertaken OHS training
Figure 4.8: Subjects receiving OHS training by workplace
The data was analysed using Fisher’s Exact Test by regrouping the
data with the Community Oral Health Program in one group and all
33 The “no” and “don’t know” responses to this question have been combined.
Mercury exposure in dental workers in Queensland
-177-
other workplaces in another group. A significantly higher proportion of
respondents (c2[1]=8.6, ρ [2-sided]=0.010, ρ [1-sided]=0.007) in the
Community Oral Health Program (50%) received occupational health
and safety training than the proportion of respondents in other work
places (11%).
There was no statistically significant association between membership
of the unexposed or exposed group and whether or not occupational
health and safety training had been received (Fisher’s Exact Test,
c2[1]=2.9, ρ [2-sided]=0.163, ρ [1-sided]=0.104).
4.4.1.3.2 Local Occupational Health & Safety Management Arrangements
As already noted above, in most instances the majority (in excess of
80%) of staff were aware of the local arrangements for the
management of occupational health and safety in the workplace or
indicated that particular arrangements (e.g. workplace health and
safety representatives) were in place.
However, only 71% (n=32) indicated that their work unit had a health
and safety committee, 47% (n=28) that there was a formal feedback
system for management to respond to employees’ workplace health
and safety concerns, and 45% (n=27) indicated that someone in their
local workplace had been assigned responsibility for coordinating
health and safety matter.
The per cent of subjects reporting that their local work unit or facility
has a workplace health and safety committee is shown in Figure 4.9.
As can be seen from the figure, the proportion of subjects reporting
“yes” and “no/don’t know” to this question appears different in the
Dental Hospital to that in the other workplaces.
Mercury exposure in dental workers in Queensland
-178-
63
38
25
75
17
83
24
77
0102030405060708090
Perc
enta
ge
DentalHospital
Children'sHospital
SchoolDental
Program
CommunityOral Health
Program
Workplace
No/Don't know Yes
Figure 4.9: Subjects reporting workplace health and safety committees in their facility
The data was analysed using Fisher’s Exact Test by regrouping the
data with the Dental Hospital in one group and all other workplaces in
another group. A significantly higher proportion of respondents
(c2[1]=5.4, ρ [2-sided]=0.034, ρ [1-sided]=0.034) in the Dental Hospital
(63%, n=5) reported being unaware of the existence of a workplace
health and safety committee in their local work unit or facility than the
proportion of respondents in other work places (22%, n=8).
It is also noted that the proportion of Dentists (56%, n=9) and Dental
Technicians (50%, n=3) who were aware of a workplace health and
safety committee being established was lower than that for Dental
Assistants (90%, n=9) and Dental Therapists (85%, n=11).
The data was regrouped in this manner and analysed using Chi-
Squared Analysis. There was a statistically significant difference in the
proportion of Dentists and Dental Technicians who were aware of the
existence of a workplace health and safety committee in their local
work unit or facility and Dental Assistants and Dental Therapists who
were aware of this (c2[1]=5.8, ρ=0.016) (Figure 4.10).
Mercury exposure in dental workers in Queensland
-179-
45
55
13
87
0
10
20
30
40
50
60
70
80
90
Per
cent
age
Dentists & DentalTechnicians
Dental Assistants & DentalTherapists
No/Don't know Yes
Figure 4.10: Awareness of occupational health and safety committee by occupation group
No significant relationships could be found regarding those persons
who were unaware of any formal feedback system for management to
respond to employees’ workplace health and safety concerns.
A variety of feedback methods were identified by those who reported
that formal feedback system was in place. These methods are shown
in Figure 4.11.
Mercury exposure in dental workers in Queensland
-180-
(Feedback option, number of cases)
Bulletin boards, 8
Notice to employees, 15
Organisation new sletter, 20
Committee minutes, 8
Videos, 8
Posters, 7
Other, 9
Figure 4.11: Formal feedback mechanisms identified by subjects
It was noted that the proportion of subjects in the Dental Hospital (37%,
n=3) and the Community Oral Health Program (56%, n=6) reporting
that someone had been appointed to coordinate occupational health
and safety matters was lower than that in the other two workplaces
(Children’s Hospital 87%, n=7, and School Dental Program 80%, n=10)
(Figure 4.12).
63
38
13
88
20
80
44
56
0
10
20
30
40
50
60
70
80
90
Perc
enta
ge
DentalHospital
Children'sHospital
School DentalProgram
CommunityOral Health
Program
No/Don't know Yes
Figure 4.12: OHS coordination responsibility allocated across workplaces
Mercury exposure in dental workers in Queensland
-181-
The data was analysed by regrouping subjects from the Dental
Hospital and Community Oral Health Program into one group and
subjects from the other workplaces in the other group. A statistically
significant difference was found in the proportion of subjects in the
Dental Hospital and Community Oral Health Program reporting that
someone had been assigned responsibilities for coordinating health
and safety matters, and the proportion of those in the Children’s
Hospital and School Dental Program who reported that someone had
been appointed (Chi-Squared Test, c2[1]=4.9, ρ=0.026).
4.4.1.3.3 Risk Assessment Processes
The risk assessment process has already been mentioned above with
respect to mercury management in the workplace.
Only 22% (n=10) of respondents (n=45) reported that their personal
protective equipment had been appropriately evaluated. The majority
(64%, n=29) of respondents did not know whether the equipment had
been evaluated. Similarly, only 20% (n=9) of respondents indicated
that Job Hazard Analyses had been done on all work processes,
machinery and work tasks in their workplace. The majority (69%,
n=31) did not know if this process had taken place. No significant
associations could be found between these and other relevant
variables.
4.4.1.3.4 Resources
A number of questions in the questionnaire survey examined the
resources available for occupational health and safety activities in the
workplace. In part they were asked if they were allowed to attend
health and safety related meetings, training and participate in accident
investigations. Responses to these questions are detailed in Table
4.10.
Mercury exposure in dental workers in Queensland
-182-
Table 4.10: Participation in health and safety related activities
Are employees allowed to : Yes %(n) No %(n) Attend health and safety related meetings (n=41) 32%(13) 68%(28) Attend health and safety related training (n=43) 12%(5) 88%(38) Participate in accident investigations (n=40) 68%(27) 33%(13)
Seventy nine per cent (79%, n=10) of those who indicated that they
were permitted to attend health and safety related meetings also
indicated that they had sufficient opportunity as an individual to actively
work to improve workplace health and safety in their area. In contrast,
42%, n=12) of who were not permitted to attend health and safety
related meetings indicated that they had sufficient opportunity as an
individual to actively work to improve workplace health and safety in
their area (Figure 4.13).
79
21
42
58
0
10
20
30
40
50
60
70
80
Per
cent
age
Able to attend health &safety related meetings
Unable to attend health &safety related meetings
Sufficient opportunity to improve health & safetyInsufficientpportunity to improve health & safety
Figure 4.13: Relationship between ability to attend safety related meetings and ability to improve OHS performance
A significant, positive association was found between being permitted
to attend safety related meetings and the opportunity to improve health
and safety performance (Fisher’s Exact Test, c2[1]=5.2, ρ [1-
sided]=0.029, ρ [2-sided]=0.032)
Mercury exposure in dental workers in Queensland
-183-
No significant associations could be found between the other two
questions outlined in Table 4.10 and other relevant variables.
Participants were also asked if occupational health and safety
committee members/representatives had sufficient time to devote the
health and safety matters. Of the respondents (n=44), 27% (n=12) felt
that there was sufficient time available, 34% (15) that the time was
insufficient, and 39% (17) did not know. No significant associations
could be found between these responses and other relevant variables.
A significant correlation was found between gender and the opportunity
to improve workplace health and safety in their specific area (Chi-
Squared Test, c2[1]=4.4, ρ=0.037) (Figure 4.14).
45
55
13
87
0
10
20
30
40
50
60
70
80
90
Perc
enta
ge
Female Male
Insufficient Sufficient
Figure 4.14: Opportunity to improve health and safety performance by gender
A significant relationship was found between the opportunity people
had to improve health and safety in their work area and those who
believed that there was sufficient information on health and safety
issues in their workplace (Figure 4.14). More detail on this relationship
is presented later in this Chapter.
Mercury exposure in dental workers in Queensland
-184-
Another aspect of the resources available to implement effective
occupational health and safety programs in the workplace is the
knowledge available. Participants were asked if they felt that
occupational health and safety committee members/representatives
had sufficient knowledge of health and safety matters to function
effectively. Fifty one per cent (51%, n=22) of respondents (n=43)
indicated that they did, 14% (n=6) that they did not, and 35% (15) did
not know. No significant association was found between this and other
relevant variables.
When asked if sufficient information was available in the workplace on
workplace health and safety issues, 67% (n=29) of respondents (n=43)
indicated that there was and 33% (n=14) indicated that there was not.
Those who knew the identity of the risk assessor were significantly
more likely to indicate that there is sufficient information available on
health and safety issues in their workplace (Fisher’s Exact Test,
c2[1]=5.5, ρ [2-sided]=0.020, ρ [1-sided]=0.018) (Figure 4.15).
Mercury exposure in dental workers in Queensland
-185-
100
0
59
41
0
10
20
3040
50
60
70
80
90100
Perc
enta
ge
Know identity of riskassessor
Do not know identity of riskassessor
Sufficient information available
Sufficient information notavailable
Figure 4.15: Relationship between knowledge of risk assessor’s identity and information available on occupational health and safety
Similarly, a significant, positive association was found between those
who indicated that they had sufficient opportunity to work actively to
improve health and safety performance in their workplace and those
who believed that there was adequate information available on health
and safety issues in their workplace (Fisher’s Exact Test, c2[1]=4.5, ρ
[2-sided]=0.046, ρ [1-sided]=0.038) (Figure 4.16).
Mercury exposure in dental workers in Queensland
-186-
79
21
4753
0
10
20
30
40
50
60
70
80
Per
cent
Sufficient opportunity Insufficient opportunityOpportunity to improve health and safety
Sufficient information availableInsufficient information available
Figure 4.16: Relationship between availability of information and opportunity to improve health and safety
A difference in the proportion of older and younger workers who
indicated that adequate information was or was not available was also
noted. Age was highly correlated with the respondents (n=43) views on
whether or not sufficient information on health and safety issues was
available at the workplace (Chi-Squared Test, c2[1]=6.5, ρ=0.011)
(Figure 4.17). Eighty nine per cent (89%, n=17) of younger workers
(<40 years) indicated that sufficient information on occupational health
and safety was available in the workplace compared with 52% (n=14)
of older workers.
Mercury exposure in dental workers in Queensland
-187-
89
11
52 48
0
102030405060
708090
Perc
enta
ge
<40 >=40Age (years) of participant
Sufficient information available
Sufficient information not available
Figure 4.17: Sufficiency of health and safety information available by age group
4.4.1.3.5 Work Related Illness and Injuries
The five most commonly reported symptoms reported by participants34
were Fatigue (mean=1.58, SD=1.16), Headache (mean=1.56,
SD=0.94), Sleep disturbance (mean=1.33, SD=1.22), Irritability
(mean=1.20, SD=0.98), and Anxiety (mean=1.11, SD=1.03) (Figure
4.18).
34 The ranking is based on the sum of the scores obtained from each respondent’s indication of the frequency of experiencing the symptoms from never=0, rarely=1, sometimes=2, most of time=3, always=4. This is similar to the ranking obtained by using the mean of the values from this scale.
Mercury exposure in dental workers in Queensland
-188-
0
10
20
30
40
50
60
70
Scor
e
Headache Fatigue Sleepdisturbance
Irritability Anxiety
Symptom
Always (4) Most of time (3) Sometimes (2) Rarely (1)
Figure 4.18: Five highest ranked symptoms
Seventy three per cent (73%, n=33) of respondents (n=45) reported
that they had been involved in a work related accident or had suffered
a work related illness. In total, the respondents reported 51 separate
injury or illness causing incidents. The most common form of injury
was a needle stick injury (27%. n=9). Back injuries (18%, n=6) were
the next most common followed by mental stress (14%, n=5) and
injuries resulting from slips, trips and falls (8%, n=3). Other injuries
included overuse injuries, cuts, eye injuries, and muscle strain. Two
incidents (4%) of illness resulting from chemical exposure (pesticides
and cleaning agents respectively) were reported.
Respondents were asked to rank the 5 most important causes of work
related accidents in their workplace. Rankings were evaluated by
scoring the highest ranked cause as “5” through to the lowest ranked
as “1”35. The sum of the scores where then calculated and the highest
scoring cause has been categorised as the highest ranking overall
through to the lowest scoring as the lowest scoring overall.
35 Note: Participants ranked the causes from “1” as most important to “5” as least important in the survey. The scoring here is therefore the reverse to that provided by the participants.
Mercury exposure in dental workers in Queensland
-189-
The five highest scoring perceived causes of accidents are shown in
Figure 4.19. The legend depicts the make-up of the overall score
calculated as described above. The next five highest perceived causes
and their scores are: Poor implementation of safety systems, 55; Lack
of experience, 46; Lack of safety knowledge, 43; Unsafe behaviour, 40;
and Careless handling of harmful substances, 27.
0
20
40
60
80
100
120
140
Scor
e
High w orkload
Insuff icientstaff numbers
Poor w orkingenvironment
Inadequatew ork
procedures
Lack oftraining
1 Least Important2345 Most important
Figure 4.19: Perceived major causes of accidents
By way of contrast, the number of respondents who identified particular
factors as being the major cause of accidents is shown in Table 4.11.
Mercury exposure in dental workers in Queensland
-190-
Table 4.11: Subjects who identify particular perceived causes of accidents
No. Perceived cause of accidents Number of subjects identifying issue (n=45)
1 High work load 33 2 Insufficient staff numbers 24 3 Poor working environment (lighting, ventilation, noise, overcrowded etc) 22 4 Lack of training 16 5 Lack of experience 15 6 Inadequate work procedure 15 7 Lack of safety knowledge 14 8 Careless handling of harmful substance 14 9 Unsafe behaviour 13 10 Misunderstanding of safety rule/s 12 11 Poor implementation of safety systems 12 12 Insufficient supervision and communication 7 13 Failure to rectify unsafe condition(s) 6 14 Poor quality supervision 5 15 Inadequate installation or poor machinery 4 16 Inadequate maintenance 4 17 Inadequate/ unsuitable personal protective equipment 4 18 Misuse machinery 4 19 Unsafe speed control 3 21 Inadequate machinery guiding 2 21 Defect of boundary indication and installation 2 22 Poorly restricted access to hazardous areas 2 23 Interference with protective devices 2 24 Failure to isolate equipment during maintenance 2
Respondents were also asked to rank the five most important activities
that would improve health and safety performance in their workplace.
These responses were scored as described above. The five highest
scoring perceived most important activities to improve health and
safety performance are shown in Figure 4.20. The legend depicts the
make-up of the overall score as described above.
Mercury exposure in dental workers in Queensland
-191-
0
20
40
60
80
100
120
140
Scor
e
Education andtraining
Employeecommitment
Employercommitment
Raisingawareness of
OHS
Workplace riskassessments
1 Least important2345 Most important
Figure 4.20: Activities needed to improve health and safety performance
The next five highest scoring activities and their scores are:
Management commitment, 64; Workplace hazard identification, 54;
Workplace health promotion program, 39; Practical guidelines for
occupational health and safety, 38; and Pre-placement and periodic
medical examinations, 27. Health surveillance was ranked 13th with a
score of 16.
By way of contrast, the numbers of subjects identifying particular
activities which are necessary to improve health and safety
performance are shown in Table 4.12.
Mercury exposure in dental workers in Queensland
-192-
Table 4.12: Subjects who identify particular activities to improve OHS performance
No. Activity identified Number of subjects identifying activity (n=45)
1 Education and training 34 2 Employee commitment 30 3 Employer commitment 22 4 Workplace risk assessments 19 5 Management commitment 19 6 Raising of awareness of occupational health and safety 17 7 Workplace hazard identification 17 8 Practical guidelines for occupational health and safety 13 9 Workplace health promotion program 11 10 Incidence surveillance 10 11 Independent auditing 9 12 Health surveillance 9 13 Pre-placement and periodic medical examinations 7 14 Occupational health and safety research 2
By both ranking methods, health surveillance and pre-placement and
periodic medical examinations were well down in the list of priorities for
improving health and safety performance in the workplace.
4.4.2 Air monitoring
4.4.2.1 Exposure Estimates
Full results of the airborne monitoring for mercury are presented in
Appendix 4.2.
In general the results obtained form this survey indicated that there is
virtually little to no mercury vapour being produced throughout the
majority of dental practices within the Oral Health Service studied. All
179 results were under the occupational exposure standard of
0.05mg/m3. The reading of mercury in air ranged from <0.003 mg/m3,
(the level of detection on the Jerome 431-X mercury vapour analyser)
to 0.021 mg/m3 of air.
An independent-samples t-test was conducted to compare the airborne
mercury contamination levels for the workplaces occupied by the
Mercury exposure in dental workers in Queensland
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exposed group and those occupied by the unexposed group. There
was no statistically significant difference in the airborne mercury
contamination levels for the exposed group’s workplaces (mean=0.003,
SD=0.0019), and the unexposed group’s workplaces (mean=<0.003,
SD=0.0000: t[177]=0.8, ρ=0.418).
A summary of the readings obtained are presented in Table 4.13.
Table 4.13: Air monitoring summary of results
Workplace (Work group)
No. of readings taken
Number of readings above level of detection36
Details of measurements above detectable level
Dental Clinic 1 (COHP) 16 2 • 0.021mg/m3: Lead amalgam waste box was opened and reading taken at mouth of opening.
• 0.007 mg/m3: Reading in same location 30 seconds after lid was opened.
School Dental Clinic 1 (SDP)
7 3 • 0.005mg/m3:Reading taken at the opening of the amalgam waste bin when opened
• 0.003mg/m3: Reading taken at rear of cupboard in which waste bin is stored.
• 0.004mg/m3: Floor of cupboard when waste removed.
Dental Van 1 (COHP) 8 0 School Dental Clinic 2 (SDP)
8 0
Dental Clinic 2 (COHP)
6 0
Dental Clinic 3 (COHP)
9 0
Dental Van 2 (COHP)
8 0
School Dental Clinic 3 (SDP)
4 0
Dental Van 3 (COHP) 8 0 Dental Clinic 4 (COHP) 7 0 Dental Clinic 5 ( COHP) 12 0 Dental Clinic 6 (COHP) 4 0 Dental Hospital (DH) 53 0 Children’s Dental Hospital (CH)
29 0
COHP=Community Oral Health Program; SDP=School Dental Program; DH=Dental Hospital; CH=Childrens Hospital
36 The level of detection is 0.003mg/m3.
Mercury exposure in dental workers in Queensland
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4.4.3 Biological monitoring
4.4.3.1 Demographics
Urine samples were collected from 39 (8 unexposed, 31 exposed) of
the 58 volunteers (13 unexposed, 45 exposed) who initially agreed to
participate in the biological monitoring component of the study.
Thirteen (13) of the initial volunteers either declined to participate, were
on holidays, or were otherwise unable to be contacted when asked to
provide urine samples. No statistically significant difference was found
in the proportion of the unexposed and exposed groups among both
the volunteers and participants (Chi-Squared Test, c2[1]=0.1, ρ=0.824).
No statistically significant difference (Chi-Squared Test, c2[3]=0.6,
ρ=0.889) was found in the proportion of volunteers and participants
from each of the workplaces.
A demographic breakdown of the exposed and unexposed groups
participating in biological monitoring is presented in Table 4.14.
Mercury exposure in dental workers in Queensland
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Table 4.14: Demographics of subjects providing urine samples
Variables Unexposed group (N=8) Num. (%)
Exposed group (N=31) Num. (%)
Gender Female (n=26) 4 (50%) 22 (71%) Male (n=13) 4 (50%) 9 (29%) Age <30 (n=4) 0 (0%) 1 (3%) 30-<40 (n=15) 4 (50%) 8 (26%) 40-<50 (n=18) 1 (13%) 10 (32%) ≥50 (n=8) 0 (0%) 8 (26%)
Mean Age (±SD) 35±6 (n=5) 45±10 (n=27) Total years of working in the Oral Health Service ≤4 yrs (n=4) 0 (0%) 4 (13%) >4-8 yrs (n=7) 2 (25%) 5 (16.% >8-12 yrs (n=7) 3 (38%) 4 (13%) >12-24 yrs (n=11) 0 (0%) 11 (36%) >24 yrs (n=3) 0 (0%) 3 (10%)
Mean years of service (±SD) 9±2 (n=5) 16±18 (n=27) Education achievement Up to and including TAFE (n=18) 3 (38%) 15 (48%) Undergraduate or above- (n=14) 2 (25%) 12 (39%) Smoking status Non-smoker (n=34) 4 (50%) 20 (67%) Ex-smoker (n=8) 1 (13%) 5 (16%) Current smoker (n=3) 0 (0%) 2 (6%) No. of amalgam fillings in mouth ≤10 (20) 3 (38%) 17 (55%) >10 (n=8) 1 (13%) 7 (23%) Mean number of amalgam fillings in mouth 9±6 (n=4) 8±5 (n=24) Working habits No. of average days work per month (±SD) 18±0 (n=5) 19±6 (n=27)
No. of average hours per month (±SD) 153±0 (n=5) 147±29 (n=27) Occupation Dentist (n=16) 2 (25%) 9 (29%) Dental Assistant (n=10) 1 (13%) 4 (13%) Dental Technician (n=6) 2 (25%) 4 (13%) Dental Therapist (n=13) 0 (0%) 10 (32%)
An independent-samples t-test was conducted to compare the ages for
the exposed and unexposed groups who provided urine samples for
analysis and for whom data was available (see Table 4.1437). There
was a statistically significant difference in the ages of the exposed
37 The following statistics which compare the exposed with the unexposed group include only those subjects who also completed the survey questionnaire. Numbers involved are set out Table 4.14.
Mercury exposure in dental workers in Queensland
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(mean=44.7, SD=9.9), and unexposed groups (mean=35.0, SD=6.2;
t[30]=2.1, ρ=0.045).
No statistically significant difference was found in the Years of Service
of the exposed group (mean=16.4, SD=18.4), and the unexposed
group (mean=8.9, SD=1.8; t[30]=0.9, ρ=0.380) or of the days or hours
worked per month by the exposed group (mean=18.6, SD=5.6 and
mean=146.9, SD=29.2 respectively) and the unexposed group
(mean=18.0, SD=0.00; t[30]=0.2, ρ=0.809 and mean=152.0, SD=0.00;
t[30]=-0.4, ρ=0.702 respectively) when tested using an independent-
samples t-test.
No statistically significant difference was found in the proportion of
males and females in the exposed and unexposed groups using the
Fisher’s Exact Test (c2[1]=1.3, ρ [2-sided]=0.402, ρ [1-sided]=0.238).
An independent-samples t-test was conducted to compare the number
of amalgam fillings in the mouths of the exposed and unexposed
groups. There was no statistically significant difference in the number
of fillings in the mouths of the exposed group (mean=7.6, SD=5.1), and
the unexposed group (mean=8.5, SD=6.2; t[26]=-0.3, ρ=0.748).
No statistically significant difference was found in the proportion of
those without or with a tertiary education in the exposed group and the
unexposed group (Fisher’s Exact Test, c2[1]=0.0 ρ [2-sided]=1.000, ρ
[1-sided]=0.624).
It was not possible to test for any difference between the unexposed
and exposed groups regarding smoking habits because of the small
sample size. However, it is noted that only 2 of the subjects for whom
data is available were current smokers.
4.4.3.2 Mercury levels in urine
Mercury levels in urine in excess of 0.01µmol/L in 6 of the 39 urine
samples received for analysis. For each of these samples the level of
Mercury exposure in dental workers in Queensland
-197-
creatinine was determined and results expressed in relation to
creatinine content to take into account the concentration of a person’s
urine. The 6 samples referred to above all came from members of the
exposed group.
An independent-samples t-test was conducted to compare mercury
concentrations in creatinine (µg of mercury/g of creatinine) of the
exposed and unexposed group. There was a statistically significant
difference in the mercury concentrations of the exposed group
(mean=0.66, SD=1.51), and the unexposed group (mean=0.01 38 ,
SD=0.00; t[30]=2.4, ρ=0.022).
Summary measures for the observed, creatinine adjusted
concentrations of mercury in urine for these 6 subjects are presented in
Table 4.15. The information on gender, age, position, workplace, and
work experience was obtained from the questionnaire survey
completed by participants. One (1) participant from the group (case 6
in Table 4.15 below) elected not to complete the questionnaire survey
so only limited information on this participant.
Table 4.15: Dental staff with detectable mercury levels in urine test
No Sex Age Current Job Position Workplace
Work experience (months)
Hg (µg/gram creatinine)
1 Male 40 Dental technician Dental Clinic 2 36 5.22
2 Male 52 Senior dental technician Dental Hospital 72 5.02
3 Female 39 Dental technician Dental Hospital 174 3.38 4 Male 53 Dentist Dental Hospital 180 3.52 5 Female 32 Dental therapist School van39 120 1.99
6 Female No information Dental Clinic 4 No information 1.25
Subjects 2, 4 & 5 in Table 4.15 were non-smokers, case 3 was an ex-
smoker and case 1 was a current smoker. No information on smoking
habits was available for case 6. 38 The level of detection was 0.01 microgram mercury/gram creatinine and this value was used for statistical purposes where no mercury was detected. 39 It was not possible to identify individual dental vans from the questionnaire survey.
Mercury exposure in dental workers in Queensland
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The full results of the biological monitoring for mercury in urine are
presented in Appendix 4.5.
4.4.3.2.1 Relationship of Mercury Exposure to Other Variables
The total mercury level in urine was ranged from non-detectable
amounts (<0.01 microgram/gram creatinine) to a maximum value of
5.22 microgram/gram creatinine. Correlation analysis or, where
appropriate, Chi-Squared analysis was undertaken to test for any
relationship between biological levels of mercury and the variables
collected in the questionnaire survey. No significant relationship
(ρ=0.05) was found between urinary mercury concentrations and the
variables including age, job task group, self-reported symptoms, fish
consumption or number of amalgam fillings in the teeth.
In an attempt to establish a “worst-case” scenario, the highest recorded
airborne concentration of mercury in each of the workplaces was
correlated with the levels of mercury detected in participants’ urine.
The relationship was investigated using Spearman’s rho correlation
coefficient. No significant correlation was found between airborne
levels of mercury contamination in the workplaces of participants and
the levels of mercury detected in their urine (r=0.17, n=36, ρ=0.319).
4.5 Discussion
The main intent of this study was to focus on the potential hazard of
dental amalgam, and its management. However there are equally
important concerns about management systems, which should not be
disregarded. The risk of mercury exposure to dental staff can be
greatly reduced with good OHS management systems in place. These
factors and the exposure of staff in the Oral Health Service are
discussed below.
When reviewing these results the limitations imposed by the small
numbers should be taken into consideration. In particular, the ability to
Mercury exposure in dental workers in Queensland
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undertake some of the statistical analyses was limited because of the
very small number of participants in the unexposed group (8 persons).
The extent of the falloff in participation in this group from the initial
volunteers was greater than expected. This problem is further
compounded by the small numbers of participants with detectable
levels of mercury in their urine and the low level of mercury
contamination in the working environment. Although positive findings
with respect to occupational health risk, these latter findings have
impacted on the statistical strength of this component of the study.
4.5.1 Demographics
4.5.1.1 Volunteers vs. Participants
Initially, 60 persons, approximately 21% of the workplace population,
volunteered to participate in the questionnaire survey. Only 45,
approximately 16% of the workplace population returned completed
questionnaires. However the group of participants showed no
statistically significant difference from the volunteers with respect to the
proportion of exposed and unexposed subjects, workplace
representation, or gender. It is therefore assumed that the participants
do not differ in any significant way from the initial volunteers.
4.5.1.2 Unexposed Group vs. Exposed Group
An unexposed group of persons not exposed to mercury formed part of
the survey group to enable comparisons to be made with respect to
mercury exposure and knowledge. No statistically significant difference
was found between the unexposed group and exposed group with
respect to age, years of service, working hours or days, number of
amalgam fillings, or gender. In addition, no statistically significant
difference was found between the two groups with respect to education
level. Because of the relatively small sample size available it was not
possible to test statistically for differences in smoking habits or
occupational group. However, it is noted that only three persons
Mercury exposure in dental workers in Queensland
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among the participants are smokers and that the percentage of non-
smokers and ex-smokers in the two groups appear similar.
There does not appear to be any statistically significant difference
between the demographics of the unexposed and exposed groups of
participants.
4.5.2 Mercury Management in the Workplace
The study also involved a self-administered questionnaire survey to
assess workers knowledge of and attitudes to various aspects
associated with health and safety management in the workplace and
the hazards and management of mercury exposure in particular. The
results of this survey provide some insight into the management of
mercury exposure in the dental workplaces. The analysis of opinions
regarding mercury management in the workplace was mostly limited to
those of the exposed group as the unexposed group is not exposed to
mercury and many of the questions seeking information on this aspect
of management are, therefore, not relevant to this group.
Two of the questions which were analysed for both groups examined
their knowledge of the ability of mercury to vaporise and enter the body
via the respiratory system and whether or not they had considered that
working with amalgam could affect their health.
The results to these questions need to be viewed in the context that all
dental staff, including the unexposed group, had attended a one hour
presentation about the effects of mercury exposure approximately 3
months prior to completing this questionnaire. This information was
specifically addressed in the presentation. It should be noted that
presentations such as this are a normal part of the awareness sessions
conducted in the workplace and were therefore not considered to have
biased the results of the study.
Mercury exposure in dental workers in Queensland
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The proportion of the exposed group (73%) who answered correctly
that mercury could be vaporised and enter the respiratory system was
significantly higher than that for the unexposed group (12%). As both
groups received the same information in the months prior to the survey
this result reinforces the widely held view that information relevant to
the workgroup is more likely to be retained by them. This is further
reinforced by the statistically significant difference noted between the
two groups with respect to whether or not they had considered that
working with amalgam could influence their health. A significantly
higher proportion of the exposed group (78%) of the exposed group
had considered this compared with the unexposed group (37%).
While compliance with the requirement to wear personal protective
equipment when working with amalgam was high among the exposed
group (95%), only 22% indicated that they believed that the equipment
had been evaluated. While the author has no particular knowledge on
whether or not the equipment had been evaluated in accordance with
the requirements of the Workplace Health and Safety Act 1995 (Qld),
the high percentage (65%) who answered “Don’t know” to this question
points to the possible need for greater feedback to staff on health and
safety issues.
This is reinforced by the finding that only 51% of the exposed group
could recall that a risk assessment on mercury exposure had been
conducted in their workplace as required by the Workplace Health and
Safety Act 1995 (Qld). Assuming that these procedures required by
the Act are being undertaken, the relatively low proportion of staff
aware of the actions might be thought to explain the finding that only
43% of the exposed group thought that the management of mercury in
the workplace effectively prevented exposure. However, no significant
association was found between subjects view of the adequacy of
measures to control mercury exposure and their knowledge of risk
assessments, the assessment of personal protective equipment, or
receipt of information on safe working procedures.
Mercury exposure in dental workers in Queensland
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Some information is being circulated to staff. For example, 78% of the
exposed group reported having received information on the safe use of
amalgam at work. It is of interest to note however that not all groups
were equally as likely to have received this information. Males were
significantly more likely to be able to recall having received the
information, than females. Only 68% of females could recall receiving
it. Dentists (85%) and dental therapists (95%) were also significantly
more likely to recall having received the information than dental
assistants (57%) and dental technicians (50%). No reason for this
discrepancy is immediately obvious. While it is possible that the
information channels used in the dental service could favour particular
occupations, it is noted that 85% of dental therapists are female.
4.5.3 Mercury Exposure
The toxic effects of mercury at the concentrations found in the
workplace have been well researched (Berlin, 1986). However, there
is no persuasive evidence that serious adverse health effects can be
attributed to the much lower levels of mercury released from dental
amalgam. If such symptoms are present, they may be so vague and
non-specific that they are extremely difficult to detect by conventional
means (U.S. Department of Health and Human Services; Public Health
Service). In the absence of such clear evidence, it is impossible to
conclude whether health hazards exist at low level of mercury
exposure.
In this study no relationship was found between the level of mercury in
the urine of, or symptoms reported by, participants and amalgam
fillings in their mouths.
However, dentists and dental personnel may be exposed to the vapour
of metallic mercury through the use of amalgam in tooth-filling
operations. Mercury spillage and direct handling of the amalgam are
the prime sources of exposure as revealed by the findings of several
investigations in various countries (Richards & Warren, 1985; Skare &
Mercury exposure in dental workers in Queensland
-203-
Bergstrom, 1990; Martin, Naleway et al., 1995). In continuing to use
amalgam, dentists should observe strict mercury and amalgam
hygiene procedures in amalgam preparation, placement, removal and
polishing to minimise the mercury exposure of staff and patients alike
(Eley & Cox, 1993).
The results of this study indicated that the level of mercury in the
exposed and unexposed groups was statistically significantly different
with the exposed group having a higher mean level of mercury in their
urine. However, of 39 dental staff tested, only 6 people (all members of
the exposed group) had detectable findings of mercury in their urine
and these were below the base line of 50 µg inorganic mercury per
gram of creatinine. The highest level detected was 5.22 µg/g
creatinine. In addition, no detectable levels of inorganic mercury were
found in the breathing zone of workers. Of the 179 airborne samples
collected in 14 different workplaces only 5 detectable levels of mercury
in the atmosphere, all well below the workplace exposure standard of
0.05 mg/m3, were recorded. Each of these measurements was taken
in locations where exposure by individuals would be difficult and, in
practice, it would be impossible for individuals to be exposed for longer
than a few minutes. Given these results, it is reasonable to conclude
that the levels of exposure to mercury are not hazardous.
The relationship between airborne mercury levels and urine mercury
concentration levels is complicated and depends on many factors,
including other sources of mercury exposure and individual differences.
Several studies indicate that an airborne exposure of 0.025 mg/m3
(TWA/8hrs) mercury compares with approximately 37 µg of
mercury/gram of creatinine in the urine. Urine mercury levels in adults
without occupational exposure are typically less than 3 µg per gram of
creatinine (Canadian Centre for Occupational Health and Safety, n.d.).
In the current study, 4 participants returned urine with mercury levels in
excess of 3 µg per gram of creatinine but careful analysis of the data
Mercury exposure in dental workers in Queensland
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provided no indication of an association between this and any
environmental, workplace or individual characteristic.
However, recordable levels of mercury in the atmosphere do indicate
that work practices can be improved at locations where results in
excess of the detectable were obtained. Similar methods of waste
disposal were not noted at the other locations where monitoring was
undertaken and the improvements made at these workplaces could be
implemented throughout the Oral Health Service.
In addition, the study examined use of personal protective equipment
(PPE) including gloves, masks, and goggles and found that over 90%
of dental staff reported wearing of PPE. There was no statistically
significant difference in mercury levels between people who used PPE
and those who did not which confirms that mercury levels in the
workplace are maintained at levels below which those which would
increase long term mercury levels in the urine of exposed workers.
No relationship was found between working hours and biological levels
of mercury. Results presented here are consistent with the findings of
(Rojas, Guevara et al., 2000) in that there was no correlation between
the quantity of amalgam prepared and working hours with levels of
mercury in urine.
This study also examined confounding factors such as the number of
amalgam fillings in the mouth of subjects. The study found no
relationship between the number of fillings and the concentration of
mercury in urine. This is comparable to results reported elsewhere
(Bratel, Haraldson et al., 1997; Harakeh, Sabra et al., 2002).
The effect of life style on mercury concentration was assessed by
studying the frequency of fish consumption, smoking, and the impact of
annual recreation leave. No significant associations were found
between these variables and the mercury concentration in their urine.
Mercury exposure in dental workers in Queensland
-205-
No relationship was found between the symptoms reported by
participants and the mercury concentrations measured in their urine.
Some studies claim that exposure is particularly risky for women of
childbearing age because a foetus is highly susceptible to adverse
effects (Vahter, Akesson et al., 2000; Takahashi, Tsuruta et al., 2001;
Lindow, Knight et al., 2003; Schober, Sinks et al., 2003). In laboratory
mice, rats, and hamsters, chronic exposure to inorganic mercury
compounds disrupts the oestrous cycle (Kajiwara & Inouye, 1992),
impedes follicular developments, and impairs embryo implantation
(Kajiwara & Inouye, 1992). Even though little is known about the
reproductive toxicity of mercury vapour in humans a few studies have
reported abnormalities in the menstrual patterns including bleeding
patterns and menstrual cycle duration among workers exposed to
mercury (DeRosis & Selvaggi, 1985; Sikorski & Juszkiewicz, 1987).
For these reasons, the effects of mercury exposure with respect to
gender differences were examined. No significant association was
found between gender and mercury levels in the urine of subjects in
this study.
4.5.3.1 Summary
The studies reported by (Richards & Warren, 1985; Skare &
Bergstrom, 1990; Martin, Naleway et al., 1995) show that dental work
involving the use of mercury can be hazardous if the processes are not
correctly controlled. The results obtained here and the lack of findings
of any significant environmental contamination or personal exposure to
mercury should therefore be interpreted as the result of a relatively well
controlled process rather than that work with mercury based amalgam
does not pose any risks to the workforce.
4.5.4 Occupational Health and Safety Management
An effective management system that emphasises involvement,
consultation, and participation at all levels in an organisation can
Mercury exposure in dental workers in Queensland
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present major change in organisational culture (Frost & Oakland, 1992;
Mallinger, 1993). The questions in this section of the survey examined
employee’s views and knowledge of the management of occupational
health and safety in the Oral Health Service. In most instances the
unexposed group and the subjects in the exposed group have been
treated as a single group as the questions are of equal relevance and
preliminary analysis revealed no statistically significant differences in
the responses of the two groups.
4.5.4.1 Training
While the provision of a safe place of work and safety working
conditions are the cornerstones of safe and healthy workplace, training
also plays an important role. The Workplace Health and Safety Act
1995 (Qld) requires that all employees be trained in aspects such as
safe working procedures, the use of personal protective equipment and
the hazards associated with their work. It is therefore surprising that a
relatively small percentage of the participants (26%) reported having
undergone health and safety training. This result stands in some
contrast with the finding that 52% of respondents reported that health
and safety training was available to all employees and that 84%
reported that they were allowed to attend health and safety related
training.
It seems likely that, although health and safety training is available for
all staff the high workloads and low staff numbers (reported by many
staff as being a significant contributor to accidents in the workplace) is
a barrier to attendance at theses courses. Other issues not
investigated by this survey may also be an issue.
It should also be noted that 77% of respondents reported that they met
their obligations under the Queensland Workplace Health and Safety
Legislation. It is difficult to understand how they would be aware of this
had they not received some health and safety training. It is possible
that training on health and safety issues forms an integral part of the
Mercury exposure in dental workers in Queensland
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work processes in place at the Oral Health Service. This conclusion is
supported by the finding that 77% of respondents reported that there
was sufficient information available on general health and safety issues
at their workplace. It is also noted that when many respondents
identified the type of training they had undertaken, they referred to
more intensive courses such as that required for becoming a
Workplace Health and Safety Officer or Representative. It is possible
that respondents interpreted this question as being a reference to
intensive training programs in occupational health and safety.
A significantly higher proportion (50%) of participants employed in the
Community Oral Health Program reported undergoing health and
safety training than employees in the other areas of the Oral Health
Service. This suggests that the use of formal training sessions on
health and safety is more widely used in some sectors of the Oral
Health Service than others.
In summary, while it is apparent that very few respondents have
undergone intensive occupational health and safety training programs,
it is also clear that the Community Oral Health Program makes more
use of formal training programs than other sections of the Oral Health
Service. The high awareness of health and safety issues among
respondents suggests that health and safety training forms an integral
part of the work process at the Oral Health Service.
4.5.4.2 Local Occupational Health and Safety Management Arrangements
The Workplace Health and Safety Act 1995 (Qld) charges employers
with the major responsibility of ensuring that workers are safe and free
from risks to their health at work. Most respondents appeared aware of
this obligation with 87% responding that the manager was responsible
for their health and safety while at work.
Mercury exposure in dental workers in Queensland
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In general, staff in the Oral Health Service have a good knowledge on
the OHS policy and management systems in place. The following
responses from respondents support this hypothesis:
Eighty nine percent (89%) stated that occupational health and
safety programs were in place,
Ninety Eight per cent (98%) stated that the work unit or facility
had a Workplace Health and Safety Officer or Representative;
Seventy one percent (71%) indicated that the work unit or
facility had a Workplace Health and Safety committee;
Eighty nine percent (89%) indicated that the Oral Health Service
had an occupational health and safety policy; and
Ninety one percent (91%) indicated that there were formal
procedures to report health and safety issues, etc. to
management.
However, not all responses were as encouraging as these:
Seventy seven percent (77%) of respondents were not aware of
who was responsible for undertaking risk assessments in their
workplace;
Only 53% were aware of who was responsible for conducting
health and safety training in their workplace;
Only 62% were aware of a formal feedback system for
managers to respond to employees’ health and safety concerns;
Only 64% were aware of anyone in their workplace responsible
for coordinating health and safety matters; and
Only 47% indicated that their position description clearly
outlined their workplace health and safety responsibilities.
Mercury exposure in dental workers in Queensland
-209-
Although 71% of respondents stated that there was a workplace health
and safety committee in their workplace, a significantly lower
proportion, only 37%, of respondents from the Dental Hospital were
aware of the existence of the committee. Assuming that these
respondents are correct and such a committee does exist, it is clear
that its activities are not widely advertised and that staff are not aware
of who are their representatives on the committee. It was also noted
that dentists and dental technicians were significantly less likely to be
aware of the existence of any workplace health and safety committee.
However, this is to be expected as, the respondents among employees
at the Dental Hospital only represented dentists and dental technicians.
The major contributing factor here is therefore the workplace at which
respondents are employed.
The workplace at which persons work was also a significant factor
regarding those participants who knew who if anyone in their workplace
had been assigned responsibility for coordinating health and safety
issues. Only 37% of respondents from the Dental Hospital and 56% of
respondents from the Community Oral Health Program indicated that
someone had been allocated this responsibility.
No significant factors could be found to suggest reasons for the lower
awareness among respondents of a formal feedback system from
management to employees, or the identity of the person responsible for
health and safety training in the workplace. However, although not
statistically significant, it is noted that the proportion of respondents
answering positively to these questions from the Dental Hospital (50%
and 25% respectively) was lower than that from all other workplaces
(65% and 60% respectively).
It was also noted that, among the exposed group, respondents who
were aware of a formal feedback system and those whose position
description clearly outlined their workplace health and safety
responsibilities were significantly more likely to indicate that the
Mercury exposure in dental workers in Queensland
-210-
management of mercury in their workplace adequately prevented
exposure to mercury. It is plausible that the feedback provided and the
concern shown in clearly outlining responsibilities could be factors in
increasing employee confidence in the health and safety measures
taken by management.
Sixty six per cent (66%) of respondents indicated that they had
sufficient opportunity to work actively to improve health and safety
performance in their area. This opportunity was significantly more likely
to be realised if they had permission to attend health and safety related
meetings, and if they were male. While the association between the
first two of these variables is reasonably obvious, that between gender
and opportunity to improve health and safety performance is less
obvious. It is possible that males in the workforce at the Oral Health
Service occupy more senior positions and therefore have greater
opportunity to influence change but insufficient data was collected in
this survey to offer this hypothesis with any conviction.
Similarly, 67% of respondents felt that there was sufficient information
available in the workplace on health and safety issues. Those less
likely to feel that sufficient information was available were those who:
did not know the identity of the person charged with
responsibility of undertaking risk assessments in their area;
If the respondent knew the identity of the person with the responsibility
of undertaking risk assessments, they presumably had access to a
person with a great deal of knowledge on occupational health and
safety issues.
had insufficient opportunity to influence health and safety
performance in their area.
People with sufficient opportunity to influence health and safety
performance presumably also have the time to seek out information
Mercury exposure in dental workers in Queensland
-211-
that is required. However, it could also be the case that having this
information available, makes it easier to realise the opportunity to
influence health and safety performance.
were older.
The reason for this is unclear as age is not a factor which has
influenced other variables in this study.
4.5.4.2.1 Summary
Staff at the Oral Health Service were largely aware of the management
systems in place to manage workplace health and safety. However,
there was less awareness of some of these measures in the Dental
Hospital where communication methods with staff could be improved.
A significant association was found between having clear statements of
occupational health and safety responsibility in position statements and
confidence that the systems in place were achieving their goals, in
particular with respect to preventing exposure to mercury, suggesting
that greater emphasis should be placed on the content of these
statements.
Similarly, those who had adequate opportunity to improve health and
safety in their work area were more likely to have permission to attend
health and safety related meetings suggesting that this could be a
major way in which they could realise this opportunity. Having
sufficient information on health and safety at the workplace was also
associated with this variable and feeling that sufficient information on
health and safety was available was, in turn, strongly associated with
knowing, and presumably having access to, the person responsible for
conducting health and safety risk assessments.
4.5.4.3 Accidents and Accident Prevention
Seventy three per cent (73%) of respondents had been involved in an
accident at work. Of the 51 incidents reported in this survey 27% were
Mercury exposure in dental workers in Queensland
-212-
needle stick injuries, 18% back injuries, 18% mental stress, and 8%
resulted from slips, trips and falls. These incidents, and the others
reported, relate relatively to the five most common causes of accidents
as perceived by the respondents. These were;
High workload;
Insufficient staff numbers;
Poor working environment;
Inadequate work procedures, and
Lack of training40.
These priorities fit well as possible control measures for the five highest
ranked symptoms suffered by participants: Headache, Fatigue, Sleep
Disturbance, Irritability, and Anxiety. All of these symptoms are
indicators of mental stress which was one of the main injuries/illnesses
reported by participants.
The resources most often identified in the literature as lacking but
necessary for a good management system are money, time, and
skilled personnel (Fisher, 1993; Juran & Gryna, 1993). In this study
respondents listed the 5 most important activities needed to improve
health and safety performance as:
Education and training,
Employee commitment,
Employer commitment,
Raising awareness of occupational health and safety, and
40 This list is based on the ranking scores as outlined in the Results section of this chapter. If ranked in order of times mentioned by the participants the list would be: 1. High workload, 2. Insufficient staff numbers, 3. Poor working environment, 4. Lack of training, and 5. Lack of experience. There is little difference in the outcome of the two possible methods of ranking these variables.
Mercury exposure in dental workers in Queensland
-213-
Workplace risk assessments.41
While these priorities differ from those discussed in the literature, their
implementation may expose the same factors.
In addition, the methods identified place a low priority on initiatives such
as medical surveillance and pre-placement and periodic medical
checks.
4.6 Summary
Dental workers and other oral health professional are at risk for
mercury exposure if amalgam is not properly handled (Food and Drug
Institute, 1992). The dental staff of this Oral Health Service had a low
average exposure to mercury, as reflected by the few persons with
detectable levels of mercury in their urine, the low levels detected, and
low level of air concentration levels. In addition, participants in this
study were generally aware of the health and safety management
systems in place. Based on this evidence, it is reasonable to assume
that the systems in place at the Oral Health Service effectively prevent
exposure of staff to mercury from the use of mercury amalgam.
This view was not however shared by a majority of the participants
concerned. The study identified a number of areas where
communication of health and safety issues could be improved and the
findings suggest that improvements in these areas could improve the
overall involvement in, and subjects’ impression of, the performance of,
occupational health and safety in the workplace.
The study revealed that high workloads and associated factors were of
concern with respect to the number of accidents in the workplace,
adverse health symptoms reported by participants, and of their ability to
participate in health and safety related activities in the workplace. It is 41 Using the alternate ranking as discussed above this list would have been: 1. Education and training, 2. Employee commitment, 3. Employer commitment, 4. Workplace risk assessments, and 5. Management commitment.
Mercury exposure in dental workers in Queensland
-214-
suggested that a reduction of workloads could result in an overall
improvement in health and safety performance in the Oral Health
Service.
Major improvements in health and safety performance were seen to be
associated with improvement in management system factors such as
employer and employee commitment, rather than a reliance on medical
surveillance.
-215-
Lead exposure management in Queensland
5.1 Background
The health effects of lead have been previously extensively reviewed
by United States Federal public health agencies: Agency for Toxic
Substances and Disease Registry (ATSDR), Centres for Disease
Control and Prevention (CDC), and National Institute for Occupational
Safety and Health (NIOSH) (National Institute of Occupational Safety
and Health, 1978; Agency for Toxic Substance and Disease Registry,
1990; U.S. Department of Health and Human Services; Public Health
Service; Centres for Disease Control). There are thousands of
scientific articles on the adverse health effects of lead in either children
or adults.
Lead is a ubiquitous and versatile metal, which has been used by
mankind for over 6000 years, and is today one of the most widely
distributed toxins in the environment (Schirnding, 2001). Lead is
associated with a continuum of health effects at both high levels of
exposure (resulting in damage to virtually all organs and organ
systems, culminating ultimately in death at excessive levels of
exposure) to effects at low levels, including effects on haeme synthesis
and other biochemical process, impairment of psychological and
neurobehavioral functions, and a range of other effects (Schirnding,
2001). Lead poisoning has been referred to as the “silent epidemic”
because at lower levels of lead exposure, there are no or few
observable symptoms, and some groups believe that this also probably
the most undiagnosed condition affecting children and adults
(Parkinson, c 2000).
5
Lead exposure management in Queensland
-216- -
Many studies have been conducted to examine the effects on workers
exposed to lead. The focus of many studies has been on relatively low
levels of lead exposure in the general population. Although levels of
exposure in many industries have declined over the last few decades,
blood lead levels in persons with occupational exposure remain above
those in the general population and are of continuing concern (U.S.
Department of Health and Human Services; Public Health Service;
Centres for Disease Control). In the U.S., more than 95% of elevated
blood lead levels in adults result from workplace exposure (Rabin,
Davis et al., 1992)
Workers with lower level, chronic or recurrent exposure to lead may
remain asymptomatic or develop vague, non-specific symptoms (e.g.,
myalgias, fatigue, irritability, headache) reflecting more subtle organ
system damage and impairment than is seen in acute intoxications.
Such individuals often continue to work and come to clinical attention
only as the result of blood lead screening or monitoring programs
(Levin & Goldberg, 2000).
5.1.1 Legislative Controls
The Queensland legislative requirements for the control of lead in the
workplace and the role of designated doctors in health surveillance
have been discussed extensively in the Literature Review (Chapter 2).
In summary, the identification of workers at risk of lead exposure
depends primarily on the risk assessment prepared by the employer.
Where an employer determines that a job may be a lead-risk job, the
employer has a number of obligations, including the arrangement of
health surveillance of any workers involved. Health surveillance,
including biological monitoring, must be undertaken by designated
doctors.
Lead exposure management in Queensland
-217- -
Many of the legislative requirements in Queensland centre around the definition of a lead risk job, defined as:
a job in which— (a) a person may be exposed to lead; and (b) a person’s blood lead level does, or may reasonably be expected to, equal or exceed— (i) for a female who is pregnant or breast feeding—0.72 µmol/L (15 µg/dL); and (ii) for a female with a reproductive capacity—0.97 µmol/L (20 µg/dL); and (iii) for anyone else—1.45 µmol/L (30 µg/dL) (Workplace Health and Safety Regulation [Qld] Schedule 9).
Designated doctors play a critical role under Queensland legislation
with respect to lead through health surveillance and the advice they
provide employers regarding the management of lead exposure in the
workplace.
The aim of this survey42 was to establish the level of compliance with
the guidelines provided to designated doctors for the surveillance of
lead in lead workers.
5.2 Methods
5.2.1 Recruitment of Participants
Participants were recruited from the 67 medical practitioners in
Queensland who are designated doctors under the QLD Workplace
Health and Safety Act (1995). Eligible participants had to be currently
registered with the Division of Workplace Health and Safety in QLD as
a lead designated doctor.
This study was conducted in collaboration with the Division of
Workplace Health and Safety in QLD and the survey of doctors was
conducted under the auspices of the Division of Workplace Health and
Safety. The decision to conduct the survey under the auspices of the
42 It should be noted that the Qld Workplace Health and Safety Act (1995) does not cover the Mining Industry. Therefore the designated doctor program discussed in this Chapter does not include this industry.
Lead exposure management in Queensland
-218- -
Division of Workplace Health and Safety was taken to improve the
response rate to the survey. In its letter of appointment of a designated
doctor, the Division of Workplace Health and Safety states that it will
seek response from doctors from time to time to evaluate the
effectiveness of the lead legislation in reducing workers’ blood lead
levels.
The Division of Workplace Health and Safety and The Human
Research of Ethics Committee at QUT approved the project protocol
including procedures for informing participants of the study process and
data collection instruments.
5.2.2 Questionnaire survey of lead designated doctors in Queensland
5.2.2.1 Occupational health service performance criteria
To evaluate lead risk management system, it is necessary to be aware
of the health services model, which subdivides data about health care
delivery into three dimensions: “structure,” “process”, and “outcomes.”
The characteristics of care in each of these dimensions can be
analysed separately according to specific measures.
The combination of these types of data provides a total picture of the
quality of care within a health care system. (Donabedian, 1985)
defined each of these dimensions as follows:
Structure refers to the material and social instrumentalities used to provide care. Structural attributes of health care delivery include: the organization and setting of care; financial, regulatory and administrative system; available resources; and the composition of the provider network.
Processes of care are those activities involving the delivery of health services, including the actual procedures involved in providing care, patient-provider relationships, diagnostic and treatment choices, and the relationships, diagnostic and treatment choices, and the availability and appropriateness of care.
Outcomes of treatment are defined as the changes in health or functional status that are directly attributable to the structure and/or processes of care. (Donabedian, 1985).
Lead exposure management in Queensland
-219- -
Donabedian (1985) emphasised that, although structure and process
must be measured, as no medical care should be provided without
them, the ultimate assessment of quality is the outcome of treatment.
Table 5.1 summarises quality measures for occupational health and
safety.
Table 5.1: Summary of quality measures that are often cited as most relevant to OHS. (After: (Pransky & Himmelstein, 1996)
Potential Quality and Performance measures
Types of data on health service
Clinical performance Access Patient experience
Structure Certification in Occupational Health Training in work fitness evaluation Comprehensive services Multidisciplinary treatment teams
Availability of specialists Availability of ancillary care professionals On-site work evaluation, health services Geographic convenience Flexible hours Low administrative barriers
Process Report of injury at 1st visit Timeliness/accuracy of communication Appropriate examination, diagnostic, treatment procedure Diagnostic accuracy Effective recognition and treatment of psychosocial issues Adherence to diagnostic/ treatment guidelines Coordination of care Continuity of care
Time to first appointment Waiting time Timely referrals Continuity of care with same provider
Patient satisfaction with provider skill Patient satisfaction with provider communication Courtesy of facility staff
Outcomes Number of adverse events Duration of disability Time of return to work Residual symptoms Symptom resolution/amelioration Generic function status Condition-specific functional status Work-specific functional status Reinjury rates Employment stability Case closure Lump sum awards
Treatment program drop-out rates due to inconvenient access
Overall patient satisfaction Treatment program drop out rate due to discomfort with providers, treatment setting, treatment plan
Lead exposure management in Queensland
-220- -
The listed performance measures are not specific to any condition, type
of job or provider setting, or system of clinical performance evaluation.
Most of the listed measures address not only patient ability to function
at work, but also in the workplace community (Pransky & Himmelstein,
1996).
The focus of this study is the structure of the health service system for
lead in Queensland and did not extend as widely as the criteria
discussed above. The 3 categories of data used to obtain information
about the management of lead health surveillance in Queensland
were:
Administrative data from the government
Self-reported survey data from lead designated doctors in
Queensland
Written policies and procedures
Through these sources, many of the criteria listed in Table 5.1 and by
Donabedian (1985) are able to be used to evaluate the service
provided.
5.2.2.2 Questionnaire design and distribution
An important aspect of this study was mail out survey to 67 medical
practitioners in QLD who are designated doctors for lead surveillance
under the Workplace Health and Safety Act 1995 (Qld).
A questionnaire was mailed to the address of each of the lead
designated doctor’s clinics in Queensland. Addresses of lead
designated doctors clinics were provided by Division of Workplace
Health and Safety in Queensland. Demographic information requested
Lead exposure management in Queensland
-221- -
included current qualifications and length of service as a designated
doctor.
In addition the questionnaire included questions in the following major
areas;
How the lead surveillance data has been collected;
How workers have been chosen for the purpose of monitoring;
How medical surveillance systems are used to comply with the
law;
The usefulness of the law in driving medical surveillance; and
How medical practitioners feel about the medical surveillance
systems.
A copy of the questionnaire and the covering letter is included in
Appendix 5.1.
Reply envelopes were provided with each mailing and a data collection
period of 3 months was allowed after mailing for return of completed
questionnaires. Due to lack of response to the first survey, participants
were given 3 more months to reply the questionnaire. After data had
been collated, telephone enquiries were made to participants who did
not respond to the questionnaire regarding their reason for not
responding.
Although the designated doctor’s name and other personal details were
not collected as part of the survey, non-responders were able to be
identified as cases were asked to mail a postcard to the Division of
Workplace Health and Safety indicating that they had completed the
questionnaire at the same time as they sent the completed
questionnaire to the researcher. This allowed respondents to be
Lead exposure management in Queensland
-222- -
identified but did not allow the names to be connected to particular
questionnaires.
This survey was conducted during Mar 2001 to Jan 2002. The follow
up of non-respondents was conducted in March 2003. During the
course of this survey two follow-up letters were sent to lead designated
doctors to seek a higher response rate. Telephone follow-up was also
used. A copy of the follow-up letter seeking information on why some
lead designated doctors had not returned the survey is included in
Appendix 5.2.
5.2.2.3 Other data sources
The other component of data collection was unstructured interviews
with OHS professionals (Lead designated doctor, OHS senior inspector
and OHS hygienist) conducted in the Occupational Health Unit of the
Division of Workplace Health and Safety during the course of the
survey. The information from these interviews was used to develop the
questionnaire and to inform the discussion in this Chapter where it is
acknowledged as appropriate.
5.3 Analysis
Data were entered in SPSS (Version 10.1.0) for Windows for advanced
data analysis. Continuous data obtained from the questionnaire survey
was analysed for normality to ensure its suitability for analysis using
standard univariate analysis. Standard univariate statistics have been
used to determine variable associations between length of service as a
designated doctor and other variables.
Unless otherwise noted, significance was set at a two-tail ρ value of
0.05.
Where data was found not to meet the requirements for normality
median, minimum and maximum levels are used to describe data
Lead exposure management in Queensland
-223- -
distribution and non-parametric equivalents (Mann-Whitney Test for
unpaired t-test, Wilcoxon Signed Ranks Test for paired t-test, Kruskal-
Wallis Test for one-way between groups ANOVA) have been used
when analysing this data. Descriptive statistics are based on counts,
percentages and odds ratios with associated 95% confidence intervals.
Categorical data obtained from the questionnaire survey was explored
with respect to adequate representation within each category and,
where necessary, categories were combined. Where associations
between groups were analysed using Chi-Squared Analysis and where
the sample size in 2x2 tables resulted in expected values of <5 the
Fischer’s Exact Test was used.
5.4 Results
The data set obtained from the questionnaire survey is included in
Appendix 5.3.
5.4.1 Response rate
Only 36 (54%) of the 67 doctors registered as designated doctors for
the purpose of lead health surveillance in Queensland returned their
completed questionnaire. Three (3) of these responses are not
considered in the following report because the questionnaire had not
been completed or was only partially completed.
Of the 31 non-respondents:
10 doctors were no longer in practice,
7 doctors were not working in the field of lead surveillance, and
5 doctors responded they had no time and were tired of
receiving questionnaires
Lead exposure management in Queensland
-224- -
as their reason for not replying. One (1) person did not receive the
questionnaire because they had moved practice. In addition, 8 doctors
were not contactable either because their telephone had been
disconnected or because they had no listed telephone number.
If it is assumed that the 8 doctors who were not contactable were
retired or no longer working, 25 of the 67 registered designated doctors
for lead surveillance in Queensland were no longer involved in the field
of lead surveillance. The response rate to the survey of practicing
designated doctors would then be 86%.
The following analysis is based on the 33 eligible responses to the
survey of lead designated doctors in Queensland.
5.4.2 General
5.4.2.1 Qualifications
Of the 33 designated doctors who responded to the survey, only 7
(21%) were registered as Fellows of the Faculty of Occupational
Medicine. Two (2) designated doctors reported having postgraduate
qualifications in occupational medicine or occupational health and
safety. Thus 27% of the respondents could be said to have formal
qualifications in occupational medicine or occupational health and
safety.
5.4.2.2 Time and role as a lead designated doctor
The mean length of service as a lead designated doctor was 3.8 years
(SD=3.2) with a maximum length of service of 15 years. The majority
of respondents (n=30) indicated that they conducted the health
surveillance program themselves (Figure 5.1).
Lead exposure management in Queensland
-225- -
77
8
17
0
10
20
30
40
50
60
70
80
Perc
enta
ge
Conducthealth
surveillance
Superviseothers
Both
Figure 5.1: Role of designated doctors
5.4.2.3 Coverage
The 33 respondents reported that they were currently undertaking lead
health surveillance in a total of 100 workplaces.
One (1) of the respondents had responsibility for 38 of these
workplaces and 1 for 19 workplaces. That is, 57% of the workplaces
where health surveillance was undertaken were supervised by two lead
designated doctors (Figure 5.2).
Of the 33 respondents, information from 24 indicated that they were
conducting health surveillance on a total of 997 workers.
Lead exposure management in Queensland
-226- -
0
5
10
15
20
25
30
35
40
Per
cent
age
of w
orkp
lace
s
1 1 2 4 5 16
Number of designated doctors
(5)
(38)
(19)
(3)(2)
(1)
Figures in brakets represent number of workplaces for which
the doctor has responsibility
Figure 5.2: Number of workplace for which designated doctors have responsibility
5.4.2.4 Recent activities
Of the 33 respondents, 30 were currently active in their role as a lead
designated doctor. Active lead designated doctors were selected on
the basis that they either; had responsibility for undertaking health
surveillance in workplaces, or of workers, or had conducted health
surveillance of workers in the past 12 months.
In the past 12 months, the respondents (n=28) indicated that they had
undertaken health surveillance on approximately 549 workers.
Respondents (n=23) indicated that they had recommended that 11
(2%) of the 549 workers monitored in the past 12 months be removed
from the lead-risk job. The respondents who did not indicate the
number of persons on whom they conducted health surveillance in the
past 12 months indicated that they recommended a further 4 workers
be removed from a lead risk job. In total, the respondents
recommended that 15 workers be removed from lead risk jobs. All of
Lead exposure management in Queensland
-227- -
these recommendations were made on the basis of elevated blood
lead levels.
5.4.2.5 General Activities
The following statistics relate to those 30 lead designated doctors who
indicated that they were active in their role.
Many (40%) of the active lead designated doctors reported that they
visited the workplaces for which they are the designated doctor
annually (Figure 5.3).
23
40
710
20
0
5
10
15
20
25
30
35
40
Per
cent
age
Never Annually Monthly Weekly Other
Figure 5.3: Frequency at which designated doctors visit workplaces Those who responded “other” (n=5) indicated the workplace
When requested or required (n=2);
Once every 5 years (n=1);
Occasionally (n=1);
Weekly to yearly depending on the workplace (n=1).
Lead exposure management in Queensland
-228- -
The activities shown in Figure 5.4 were undertaken by active lead
designated doctors when they visited workplaces for which they had
health surveillance responsibilities.
9287 87
92 92
50556065707580859095
100
Perc
enta
ge w
ho o
bser
ve
each
act
ivity
Work ac
tivitie
s
Substa
nces
used
Hygien
e con
dition
s
Contro
l mea
sures
Eating
/Ablu
tion f
aciliti
es
Figure 5.4: Activities observed at workplaces by designated doctors Most of the active lead designated doctors also provide information on
lead to employers and workers (Figure 5.5).
Lead exposure management in Queensland
-229- -
73
27
80
20
0
10
20
30
40
50
60
70
80
Perc
enta
ge p
rovi
ding
in
form
atio
n on
lead
To Employers To workers
Yes No
Figure 5.5: Provision of information to employers and workers The active lead designated doctors provide a range of types of
information on lead to both employers and workers (Figure 5.6).
3742
9296
2517
2929
0102030405060708090
100
Perc
enta
ge
Brochu
res
Advice
Training
course
s
Person
alise
d lett
ers
To employersTo workers
Figure 5.6: Information provided to employers and workers by designated doctors
No other information was indicated as being provided to either
employers or workers at the workplaces.
Lead exposure management in Queensland
-230- -
5.4.2.6 Other
To maintain or improve their knowledge of occupational health issues
the respondents (n=33) indicated that they undertook a number of
activities (Figure 5.7).
6
42
80
4236
01020304050607080
Perc
enta
ge
unde
rtak
ing
activ
ity
Nil
Attend
confe
rence
s
Read j
ourna
ls
Profes
siona
l mee
tings
Furthe
r edu
catio
n
Figure 5.7: Activities to maintain/improve knowledge The majority (76%) of respondents indicated that they had received
sufficient information from the Division of Workplace Health and Safety
to enable them to fulfil their role. Most (90%) indicated that they felt
that the system was working effectively. A minority of respondents
(31%) indicated that changes were necessary to improve the health
surveillance system while 90% believed the system was working
effectively (Figure 5. 8).
Lead exposure management in Queensland
-231- -
76
90
31
0102030405060708090
100
Per
cent
age
SufficientInformation
(n=33)
Systemworking
effectively(n=31)
Changesrequired(n=32)
Figure 5.8: Respondents views of current system The additional information some respondents indicated was necessary
to fulfil or improve their performance as lead designated doctors
included43:
A seminar, conference, or meeting to provide updates on the
current state of knowledge and how to handle difficult cases
(n=4),
Updates on recent research, legislative changes, and case
studies (n=6).
Those who indicated that program changes were necessary to improve
the lead health surveillance program suggested the following changes:
Only doctors qualified in occupational medicine should
undertake surveillance (n=1),
Better enforcement of workplace requirements (e.g. ventilation)
(n=6) and paperwork (n=1),
43 These have been summarised along similar themes.
Lead exposure management in Queensland
-232- -
Evidence based review of Workplace Exposure Standards and
Biological Exposure Indices (n=1),
Should be mandatory for results of individual monitoring to be
copied to responsible management, for management to
maintain a database (protecting individual confidentiality) for
periodic audit for designated doctor and/or Division of
Workplace Health and Safety (n=1).
5.4.3 Comparative analysis
5.4.3.1 Qualifications of designated doctors
As noted previously, 2 designated doctors supervise the lead health
surveillance in 57% of the workplaces. Both of these designated
doctors have qualifications in occupational medicine or occupational
health and safety. Lead designated doctors are responsible for
overseeing the health surveillance of workers in 66% of the workplaces
reported in this study. However, no association was found between the
number of workplaces and whether or not the designated doctor had
qualifications in occupational medicine or occupational health and
safety (Mann-Whitney U Test, Z=-0.07, ρ=0.946).
Designated doctors with qualifications in occupational medicine or
occupational health and safety had responsibility for the lead health
surveillance for 50% of workers. No association was found between
the size of the workforce group provided with health surveillance and
whether or not the designated doctor had qualifications in occupational
medicine or occupational heath and safety (Mann-Whitney U Test, Z=-
1.91, ρ=0.057).
In the past 12 months, designated doctors with qualifications in
occupational medicine or occupational health and safety had seen 57%
of the workers on whom health surveillance had been conducted.
There was no association found between the number of workers
Lead exposure management in Queensland
-233- -
having health surveillance in the past 12 months and the qualifications
of the designated doctor (Mann-Whitney U Test, Z=-1.61, ρ=0.107)
(Figure 5.9).
57
43
0
10
20
30
40
50
60
Perc
enta
ge o
f hea
lth
surv
eilla
nce
in p
astt
yea
r
Yes No
Qualif ications in occupational medicine and/or occupational health and safety
Figure 5.9: Health surveillance in past year by qualifications Attendance at conferences to maintain or improve knowledge of
occupational health and safety issues was correlated with qualifications
in occupational medicine or occupational health and safety (Fisher’s
Exact Test, c2[1]=7.81, ρ [2-sided]=0.011, ρ [1-sided]= 0.008,) (Figure
5.10) Ninety per cent (90%) of designated doctors with qualifications in
occupational medicine or occupational health and safety indicated that
they attended conferences for this purpose compared with 30% of
designated doctors without these qualifications.
Lead exposure management in Queensland
-234- -
88
13
30
70
0102030405060708090
Perc
enta
ge
Yes NoQualifications in occupational medicine and/or occupational health and safety
Attends conferencesDoes not attend conferences
Figure 5.10: Attendance at conferences by qualification44 There was no association between qualifications and those who read
journals to maintain or improve their knowledge of occupational health
and safety issues (Fisher’s Exact Test, c2[1]=2.07, ρ [2-sided]=0.291, ρ
[1-sided]=0.198).
Attendance at professional body meetings to maintain or improve
knowledge of occupational health and safety issues was also
correlated with qualifications in occupational medicine or occupational
health and safety (Fisher’s Exact Test, c2[1]=7.81, ρ (2-sided)=0.011, ρ
(1-sided)= 0.008). Eighty eight per cent (88%) of designated doctors
with qualifications in occupational medicine or occupational health and
safety indicated that they attended professional body meetings for this
purpose compared with 30% of designated doctors without these
qualifications. This result was identical to that for attendance at
conferences reported above.
Designated doctors with qualifications in occupational medicine or
occupational health used more methods to maintain or improve their 44 The rounding of percentages in this and other instances means that not all totals will equal exactly 100%.
Lead exposure management in Queensland
-235- -
occupational health and safety knowledge (mean = 3, SD = 1.3) than
designated doctors without these qualifications (mean = 2, SD = 1.3)
(Figure 5. 11). The difference between the number of methods used
by the two groups was statistically significant (Independent-samples t-
test, t(30)=-2.78, ρ=0.009).
923N =
Qualif ication in occupational medicine or occupational health and safety
YesNo
Num
ber o
f met
hods
use
d to
mai
ntai
n kn
owle
dge
5
4
3
2
1
0
-1
3026
Figure 5.11: Number of methods used to maintain/improve knowledge by qualification (The box represents the interquartile range which contains 50% of values. The bars extend to the highest and lowest values, including outliers. The heavy line across the box indicates the median.)
Those designated doctors who did not have qualifications in
occupational medicine or occupational health and safety were
significantly less likely to supervise others than those who had these
qualifications ((Fisher’s Exact Test, ρ (2-sided)=0.014, ρ (1-sided)=
0.014) (Figure 5.12)
Lead exposure management in Queensland
-236- -
56
10
0
10
20
30
40
50
60
Per
cent
age
supe
rvis
ing
othe
rs
Yes No Qualifications in occupational medicine and/or occupational heath and safety
Figure 5.12: Supervision of others by qualification No association was found between the qualifications of designated
doctors and whether or not they indicated that they:
Had received sufficient information from the Division of
Workplace Health and Safety to fulfil their role (Fisher’s Exact
Test, c2[1]=0.03, ρ [2-sided]=1.000, ρ [1-sided]=0.626);
Feel that the lead health surveillance system is working
effectively (Fisher’s Exact Test, , c2[1]=2.28, ρ [2-sided]=0.195,
ρ [1-sided]=0.195); or
Believe that any changes are necessary to improve the lead
health surveillance program (Fisher’s Exact Test, , c2[1]=1.75, ρ
[2-sided]=1.000, ρ [1-sided]=0.958).
5.4.3.2 Other
No association was found between years of service as a lead
designated doctor and other relevant variables including whether they
indicated that they:
Lead exposure management in Queensland
-237- -
Had received sufficient information from the Division of
Workplace Health and Safety to fulfil their role (Mann-Whitney U
Test, Z=-0.09, ρ=0.933);
Feel that the lead health surveillance system is working
effectively (Mann-Whitney U Test, Z=-1.35, ρ=0.179); or
Believe that any changes are necessary to improve the lead
health surveillance program (Mann-Whitney U Test, Z=-0.14,
ρ=0.886).
5.5 Discussion
5.5.1 Appointment process
The only requirements for a doctor to become a lead designated doctor
in Queensland are to complete an application form providing proof of
medical qualifications and contact details and to inform the Division of
Workplace Health and Safety that you wish to be a lead designated
doctor (Smith, D. 2001, pers. comm., March45).
The Division of Workplace Health and Safety then forwards a letter of
appointment and an information package containing:
A summary of the health surveillance requirements for lead,
Guidelines for health surveillance for inorganic lead: Information
for designated doctors (this information is based on Draft
Guideline for Health Surveillance for Inorganic Lead developed
by the National Occupational Health and Safety Commission in
1998),
45 The information cited as personal communication (pers. comm) in this section was obtained during the unstructured interviews discussed in the Method section of this Chapter.
Lead exposure management in Queensland
-238- -
Lead toxicology (including summary information on lead
toxicology developed by the Division of Workplace Health and
Safety),
Respiratory protection for lead workers (including a summary of
respirator classes and their performance characteristics),
Lead workplace forms (a set of forms which the employer in a
lead workplace is required to complete),
Some articles on lead exposure to children from scientific
journals, and
Part 14 – Lead from the Workplace Health and Safety
Regulation 1997 (Qld) (Lead designated doctor 46 , 2000
pers.comm. March).
5.5.2 Maintenance of designated doctor s database
The low response rate (54%) to this survey indicates poor maintenance
of the database and/or poor compliance with the request provided to
lead designated doctors in the information package forwarded to them
by the Division of Workplace Health and Safety seeking their
assistance “in maintaining a list of coded blood lead results for each
lead workplace for which health surveillance is provided” (Division of
Workplace Health and Safety n.d.). The material makes it clear that
“The information will be sought from time to time and will be used as a
gauge of the overall effectiveness of the lead legislation in reducing
workers’ blood lead levels.”
The information sought in the questionnaire included information from
this list and was sought by the Division of Workplace Health and Safety
under their letterhead.
46 The name of the designated doctor has been omitted to ensure confidentiality. The information was obtained during an unstructured interview that formed part of this study.
Lead exposure management in Queensland
-239- -
The follow-up with non-responders revealed that a large number of
them were no longer in the field of lead health surveillance. If the group
of lead designated doctors who were not contactable are included in
this group, the response rate from practicing lead designated doctors
would be 86%.
Although this is relatively high, in these circumstances, where the lead
designated doctor is appointed by the Division of Workplace Health
and Safety which requested the information sought in the survey, a
100% response rate could be expected. This confirms the information
provided by the designated doctor in the unstructured interview (2000
pers. comm. March) that “there is no strong obligation to report DWHS
about lead surveillance in this agreement47”.
The number of non-practicing lead designated doctors on the
database and the number of incorrect contact details suggests that the
database of lead designated doctors is inadequately maintained by the
Division of Workplace Health and Safety. Although not strictly
equivalent, this suggests that the regulatory framework is not able to
meet fully the criteria set out in Table 5.1 that there should be an
availability of specialists.
5.5.3 Qualifications
As noted above, minimal qualifications are necessary to become a lead
designated doctor in Queensland. The criteria set out in Table 5.1
stipulate that the clinician should have certification in occupational
health. Only 27% of the respondents had qualifications in occupational
medicine or occupational health and safety.
Some possibly important differences were noted between those with
and without these qualifications from the responses received. For
example, those with qualifications in occupational medicine or
47 The “agreement” refers to the information package forwarded to lead designated doctors.
Lead exposure management in Queensland
-240- -
occupational health and safety were significantly more likely to make
use of more sources of information to maintain or improve their
knowledge of occupational health and safety. It is notable that lead
designated doctors had responsibility for conducting lead health
surveillance 66% of the workplaces. However, there was no
statistically significant difference in the overall number of workers who
underwent health surveillance by either group overall or in the last 12
months.
While it may appear that lead designated doctors with qualifications in
occupational medicine or occupational health and safety are
responsible for a larger number of workers each, it was also noted that
those without these qualifications were significantly less likely to
supervise others.
Although not canvassed specifically in the questionnaire, no differences
could be found which suggested that the lead designated doctors
without qualifications in occupational medicine or occupational health
and safety were providing an inferior service to other lead designated
doctors. A more detailed study of the service provided by these two
groups would be required before any conclusions on the quality of
service could be drawn. However, it should be noted that doctors
without qualifications in occupational medicine or occupational health
and safety are preforming a number of activities in the workplace for
which these qualifications would usually be considered essential
(Figures 5.4, 5.5 and 5.6).
In summary, it is possible that lead designated doctors with
qualifications in occupational medicine or occupational health and
safety maintain a better awareness of occupational health and safety
issues through the greater range of sources that they use to remain
informed. In addition, although these lead designated doctors are
individually responsible for a greater number of workplaces and
Lead exposure management in Queensland
-241- -
workers, it is likely that some of this responsibility is delegated to others
through their greater likelihood to supervise others.
5.5.4 Regulatory compliance
The decision on what constitutes a lead risk job is made by the
employer at the workplace. If the process is assessed to include a lead
risk job the employer must notify the chief executive of the Division of
Workplace Health and Safety within 28 days (Workplace Health and
Safety Regulation 1997 [Qld] S129[7]). However, there is little, if any,
checking of the quality of the risk assessments (designated doctor,
2000, pers. comm. March) and, if the employer decides that a process
does not include a lead risk job, the employer is under no obligation to
inform the chief executive.
Although 90% of respondents indicated that the system was working
effectively, 31% indicated that the system could be improved. Six (6) of
those who made comments on suggested changes argued for better
enforcement in the workplace.
5.5.4.1 Rate of surveillance
There are no records of the number of workers in lead risk jobs in
Queensland. Despite the requirement that employers “give the chief
executive notice, in the approved form, of the results of the health
surveillance within 6 months of receiving the report (Workplace Health
and Safety Regulation 1997 [Qld] s 133[4][d]), the “Division has
accepted that collected blood lead results (coded data for
epidemiological purposes) are now unavailable through employers
(Division of Workplace Health and Safety n.d.).
It is therefore not possible to comment on whether or not workers in
lead risk jobs are undergoing health surveillance at the rate, minimum
of once each 6 months, recommended by the Division of Workplace
Lead exposure management in Queensland
-242- -
Health and Safety in its Information Package to lead designated
doctors.
An indication of the rate of health surveillance is given thorough the
results of the survey in that the respondents indicated that they were
undertaking surveillance on approximately 997 workers. In the past 12
months they had undertaken health surveillance on 55% of these. This
would seem to indicate under-compliance with the recommendations
outlined above. However, there are a number of factors which could
confound this result:
The number of workers for whom respondents indicated that
they were undertaking health surveillance may not all be in lead
risk jobs as defined by the Regulation;
Not all respondents provided information on the number of
health surveillances in the past year (In four instances when
respondents indicated that they had removed workers from the
job because of high blood lead levels in the past 12 months,
they did not report undertaking any lead surveillance in the
same period.);
The requirement to undertake health surveillance at a minimum
of every 6 months is a recommendation in the Information
Package provided to lead designated doctors and is not a
requirement of the Regulation once the initial testing at the time
of commencement of employment has been completed.
Most lead designated doctors reported that they were making regular
visits to workplaces and a high per cent were providing advice to
employers and workers (92% and 96% respectively) as required by the
Regulation.
In summary, although the respondents reported that the system of lead
health surveillance was working well, increased regulatory compliance
Lead exposure management in Queensland
-243- -
inspections appear warranted. In addition, the current system provides
no indicators of the success or otherwise of its ability to protect workers
from the adverse effects of exposure to lead. The system depends
heavily on the quality of the risk assessment undertaken by the
employer who may have no expertise in such matters and is not
required to seek expert advice unless, as a result of the risk
assessment, the employer decides that someone is at risk.
5.5.5 Improvements
A number of possible improvements to the system were identified by
respondents and these are presented in the Results section of this
Chapter. It is notable however that although 76% of respondents
indicated that they had received sufficient information from the Division
of Workplace Health and Safety to enable them to fulfil their role as a
lead designated doctor, approximately 30% indicated a desire to be
better informed on issues related to their role.
5.6 Summary
The lead health surveillance program in Queensland provides no
indicators of the overall impact that the legislation is having on reducing
workers’ exposure to lead and its adverse health effects. The system,
as it has been designed, appears to be working relatively effectively but
improvements to enforcement and record keeping are necessary. In
particular, the records of lead designated doctors maintained by the
Division of Workplace Health and Safety need regular updating. This
could be done in conjunction with occasional (possibly once every two
years) update sessions to provide lead designated doctors with
information on recent additions to knowledge regarding lead and its
control.
In addition, the current system of appointing lead designated doctors
does not require that they are able to demonstrate any competency for
Lead exposure management in Queensland
-244- -
the role to which they are being appointed and no assessment of their
performance is undertaken by the appointing body.
-245-
Occupational health and safety management systems in Australia and Korea
6.1 Background
In attempting to establish the way that strategies that result in long-term
illness and injury reduction and are able to be formally evaluated, it is
clear that occupational health and safety management presents
challenges for all concerned. The causes of illness and injury are
always complex, are often multidimensional and potentially impact on
not only the organisation but also society in general (Quinlan & Bohle,
1993). It is therefore vital that any intervention strategy addresses
causation factors at a number of levels within the organisation, and
includes factors such as the physical environment of the workplace, the
way the work is organised and the individuals involved (Emmett &
Hickling, 1995). It is also clear that the overall effectiveness of the
strategies must be able to be evaluated in terms of improvement
brought about in the management of occupational health and safety.
Probably the most common strategy being examined around the world is the introduction of formalised occupational health and safety management systems. The implementation of management systems presents difficulties for organisations. It also presents difficulties for regulators who struggle to effectively promote and market the benefits of an occupational health and safety management system and also appear to have difficulty in enforcing such systems. It is widely acknowledged that if successful, a safety management system may achieve far more than previous strategies through co-operation and changing the norms of the business community and through the development of a safety culture within the organisations (Gunningham, Johnstone et al., 1996).
There is little survey data to identify particular industry sectors that are
greater users of occupational health and safety management systems
than others. Similarly, there is mainly anecdotal evidence that smaller
organisations are less likely to have implemented an occupational
6
Occupational health and safety management systems in Australia and Korea
-246-
health and safety management system than larger organisations.
There are examples of a wide variety of sectors that use occupational
health and safety management systems and some examples of
smaller organisations that have developed an occupational health and
safety management system. (Bottomley, 1999).
In Australia, in 1994, 44.5% of the workforce works in businesses with
<20 employees in 1,140,000 separate business premises as shown in
the following extract from the National Occupational Health and Safety
Commission (2004b):
make up 31.7% of all employees.
In South Korea, in 1988, small manufacturing enterprises (<20
employees) comprised 56.9% of all manufacturing establishments and
employed 11.1% of the workforce as shown in the following extract:
Occupational health and safety management systems in Australia and Korea
-247-
Extracted from: Kim & Nugent, 1994.
This Chapter will examine the level of occupational health and safety
management system implementation in the workplace. The need for
research on health and safety management systems arises from the
intensive promotion of and an apparent increasing interest at enterprise
level in health and safety management systems. The few research
studies seeking to draw out the connection between health and safety
management systems and work related injury or disease outcome data
give an indication of defining characteristics of better performing
enterprises, but they also reflect the methodological constraints relating
to the measurement of health and safety performance (Gallagher,
1997). Evidence on the performance of alternative systems is scant.
6.2 Introduction
In the preceding chapters three distinct types of workplaces have been
investigated in terms of exposure to heavy metals. In two of these the
actual workplaces and exposure of workers have been examined while
in the third setting the role of designated doctors in the protection of
workers has been evaluated.
This part of the study aimed to identify the existing occupational health
and safety management systems in an Oral Health Service and lead
Occupational health and safety management systems in Australia and Korea
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industry companies in Queensland, and fluorescent lamp
manufacturing companies in Korea, and to ascertain whether or not
any of the system elements could predict health and safety
performance.
For this aim there are two questions which need to be addressed:-:
Are workers’ exposures to hazardous substances being controlled
at the levels required by OHS standards?
Does legislation impact on the way in which occupational heath and
safety is managed in the workplace?
The investigation was conducted using self-assessment questionnaire
survey modified from the Guidelines on occupational safety and health
management systems (International Labour Office, 2001). The
evaluation instrument (the questionnaire) was developed by a panel of
5 occupational health and safety experts and evaluated by a panel of 9
senior members from the Safety Institute of Australia.
This discussion is in two parts. The first, discussing a number of the
key elements of occupational health and safety management systems,
and identifying the implications of these for the development of an
International Labour Office type of occupational health and safety
management systems document in the mercury and lead industry in
Korea and Australia.
6.3 Methods
6.3.1 Development of the self-assessment occupational health and safety management system questionnaire
The nominal group technique (Delbecq, Van de Ven et al., 1986) was
used to develop the questionnaire designed to evaluate the
occupational health and safety performance of an organisation based
Occupational health and safety management systems in Australia and Korea
-249-
on the Guidelines on occupational safety and health management
systems (International Labour Office, 2001). The group involved five
occupational health and safety professionals with expertise in
workplace assessment and auditing in Australia. Each member of the
group had been involved in occupational health and safety practice at a
senior level for at least 10 years. The panel’s 5 members represented
academia, industry, government and professional associations. These
individuals are some of the most senior individuals in each of their
respective fields. Two (2) had been involved in the writing of AS/NZS
4801 and AS/NZS 4804 (Standards Australia/Standards New Zealand,
2001b; Standards Australia/Standards New Zealand, 2001a).
The Guidelines on occupational safety and health management
systems (International Labour Office, 2001) were chosen as the
standard upon which the evaluation instrument would be based
following a review of 6 publicly available systems. These were:
Trisafe (Queensland, Australia);
Safety Map (Victoria, Australia);
Korean regulatory system;
OHASH 18001 (British standard);
American Industrial Hygiene Association (USA);
Guidelines on occupational safety and health management
systems (International Labour Office, 2001).
Five general criteria were established to guide the review process;
the instrument needs to be widely applicable, universally;
the measurement of effectiveness determinations need to be
both valid and reliable;
Occupational health and safety management systems in Australia and Korea
-250-
key occupational health and safety performance variables
needed to be identified;
it must be easy to administer; and
outcome determinations must be easy to interpret (Redinger &
Levine, 1998).
Although it was not considered that it met all of these criteria, the
Guidelines on occupational safety and health management systems
(International Labour Office, 2001) was chosen as the appropriate
instrument upon which to base the questionnaire. The document is
widely accepted as an appropriate international standard, it identifies
key occupational health and safety management system variables, it is
designed to be applicable in a wide variety of industries, and it is easy
to interpret. Unlike SafetyMap and Trisafe, it did not have a developed
assessment guideline, but this was the role of the expert panel.
It was recognised that the questionnaire would be too long if all of the
variables in the Guidelines on occupational safety and health
management systems (International Labour Office, 2001) were
investigated. The expert group was therefore given the task of
identifying key performance variables, including both basic (essential)
and more advanced (desirable) elements.
The expert panel was also asked to adhere, as far as possible, to the
principles of criteria validity and reliability based on their experience in
using a wide range of audit tools. This request was made in the
context of there being no research which has attempted to validate the
use of audit tools as a measure of occupational health and safety
performance or of the validity of any particular audit tool.
Based on the Guidelines on occupational safety and health
management systems (International Labour Office, 2001) the
Occupational health and safety management systems in Australia and Korea
-251-
questionnaire contains 54 questions which are grouped into 4
categories:
policy,
organising,
planning and implementation, and
evaluation.
This construct is significant in that it reflects the open systems nature of
occupational health and safety management systems and their need to
interact with the organisation as a whole, as well as with the external
environment. Once the questionnaire was developed it was circulated
among 9 leading members of the Safety Institute of Australia
(Queensland Division) chosen by the Queensland State Executive of
the Safety Institute of Australia. This review panel was asked to review
the questionnaire for its validity as a tool for measuring occupational
health and safety performance given the limitations imposed by it being
in a self-administered questionnaire format and to make suggestions
for improvement.
Once the recommendations of the review panel were incorporated the
questionnaire was translated into Korean. This involved some slight
changes in the wording of some of the questionnaires to avoid any
confusion over terminology.
Copies of the English and Korean versions of the questionnaire are
presented in Appendix 6.1.
6.3.2 Selection of cases
The questionnaire was distributed to the senior manager of the Oral
Health Service that formed the focus of the study described in Chapter
4. To the fluorescent lamp manufacturing companies that were the
focus of the study described in Chapter 3 and to all companies with
Occupational health and safety management systems in Australia and Korea
-252-
lead risk jobs on the Queensland Division of Workplace Health and
Safety’s database. These latter companies include those companies
serviced by designated doctors who were the focus of Chapter 5.
The study was conducted from January 2001 to March 2003. All
participants provided written informed letter of consent. The study
protocol was approved by the Division of Workplace Health and Safety
in QLD and the Human Research Ethics Committee, QUT (Ref
No.2468H).
The questionnaire to lead risk companies was mailed to total a 198
lead risk registered companies (68-Brisbane, 33-South West
Queensland, 16-Gold Coast, 25-North Queensland, 38-Wide Bay -
Sunshine Coast, 18 Central Queensland). Twenty questionnaires were
undelivered to the lead risk companies due either to a change of
address or the company ceasing to trade. Two follow-up letters were
sent to the lead risk companies during the course of the study.
Forty (40) lead-risk companies (22%) completed and returned the
questionnaire.
The Korean translated questionnaire was mailed to the Department of
Preventive Medicine & Institute for Environmental Health College of
Medicine in the Korea University where the agency for health
surveillance, air monitoring, and health and safety education for
mercury industries in Korea is situated. The Director of the Department
visited five fluorescent manufacturing companies to administer the
questionnaire survey. The other company declined the offer to
participate in the study.
6.4 Analysis
Data were entered in SPSS (Version 10.1.0) for Windows for advanced
data analysis. Continuous data obtained from the questionnaire survey
was analysed for normality to ensure its suitability for analysis using
Occupational health and safety management systems in Australia and Korea
-253-
standard univariate analysis. Standard univariate statistics have been
used to determine variable associations between number of employees
and type of firm.
Unless otherwise noted, significance was set at a two-tail ρ value of
0.05.
Categorical data obtained from the questionnaire survey was explored
with respect to adequate representation within each category and,
where necessary, categories were combined. Where associations
between groups were analysed using Chi-Squared Analysis and where
the sample size in 2x2 tables resulted in expected values of <5 the
Fischer’s Exact Test was used.
When analysed for the degree of implementation of occupational health
and safety management system components, the data has been
regrouped as shown below (Table 6.1):
Table 6.1: OHSMS components scale used for data collection and analysis
Data as collected in questionnaire Data regrouped for analysis No system in place Yes, but system not implemented
System not implemented
Part of the system implemented Part of the system implemented and full implementation planned
System partially implemented
The system is fully implemented System fully implemented
If it was still not possible to analyse the data because of small cell sizes,
it was regrouped to compare those organisations that had fully
operational systems with those who had a system partially
implemented or did not have a system as follows (Table 6.2):
Occupational health and safety management systems in Australia and Korea
-254-
Table 6.2: Second OHSMS components scale used for data collection and analysis
Data as collected in questionnaire Data regrouped for analysis No system in place Yes, but system not implemented Part of the system implemented Part of the system implemented and full implementation planned
System partially implemented or no system
The system is fully implemented System fully implemented
Similarly, when analysed for whether particular elements of the
occupational health and safety program are in place, the data collected
have been regrouped and presented as follows (in most instances only
the “yes” responses have been presented in graphs) (Table 6.3):
Table 6.3: Scale for OHSMS elements in place for data collection and analysis
Data as collected in questionnaire Data regrouped for analysis Yes Yes No Not sure
Other
Results from the questionnaire study have been presented firstly
looking at the overall results from all organisations. The results are
then presented for the Australian firms only, including the 40
respondents from the lead risk firms and the Oral Health Service and
then for the Korean firms. A summary of responses for the Oral Health
Service is presented at the end of the Results section.
When presenting the results from Australian firms, the companies have
been compared on the basis of the number of employees (≥30
employees) or (<30 employees). The figure of 30 employees is has
been chosen because of its importance under Queensland legislation
where the study was conducted. Workplaces that normally employ 30
or more persons must appoint and train a Workplace Health and Safety
Officer whose duties include advising the employer on health and
safety related matters (Workplace Health and Safety Act 1995 [Qld]
Occupational health and safety management systems in Australia and Korea
-255-
Part 8). It should be noted that one Australian respondent did not
provide details on the number of employees at the workplace. Most
comparisons based on size of workplace therefore contain one less
than the total number of respondents who answered the relevant
question in the survey.
During preliminary analysis of the Korean data it was noted that
differences arose in the responses of organisations with fewer or
greater than 200 employees. This figure has therefore been used as a
distinction between smaller and larger organisations when presenting
the Korean data.
6.5 Results
The data set obtained from the Australian and Korean surveys is
included in Appendix 6.2.
6.5.1 Demographics (All respondents)
Responses were received from:
Oral Health Service (a senior manager charged with
responsibility for overseeing the operation of the Service;
40 organisations registered as lead risk workplaces with the
Division of Workplace Health and Safety in Queensland (17
radiator repair workshops and 23 other workplaces); and
5 fluorescent lamp manufacturing companies in Korea.
The other industries represented in the response from lead risk
companies in Queensland include; analytical laboratories, detergent
manufacturers, electricity generators, lead lighting firms, farm
machinery manufacturers, mining exploration assayers, painting
companies, powder coating companies, pvc & polyethylene pipe
Occupational health and safety management systems in Australia and Korea
-256-
manufacturers, road construction companies, sand blasters, and valve
manufacturers.
6.5.1.1 Demographics (Australia)
The 4048 (39 lead-risk companies, 1 oral health service) Australian
respondents employed a total of 2109 workers. Radiator repair
companies comprised 43% (n=17) of the companies but only employed
3% (n=63) of the workforce (Figure 6.1). When tested using an
independent-samples t-test, there was a statistically significant
difference in the number of persons employed by radiator repair
companies (mean=3.5, SD=2.2) and other companies (mean=89.1,
SD=123; t(22)=-3.3, ρ=0.003).
43
58
3
97
57
43
0
100
0%10%20%30%40%50%60%70%80%90%
100%
Perc
enta
ge
% w
orkp
lace
s
% e
mpl
oyee
s
% w
orkp
lace
s<3
0 em
ploy
ees
% w
orkp
lace
s≥3
0 em
ploy
ees
Other
RadiatorRepair
Figure 6.1: Employment characteristics by type of company (Australia) The type of workplace was also statically associated with employment
size below or in excess of 30 (Fisher’s Exact Test, c2(1)=9.9, ρ 2-
sided=0.002, ρ 1-sided=0.001). All of the radiator repair enterprises for
which data was obtained (n=16) employed <30 employees (Figure
6.1).
48 One respondent did not provide any details on the number of employees at the workplace.
Occupational health and safety management systems in Australia and Korea
-257-
6.5.1.2 Demographics (Korea)
The 5 Korean fluorescent lamp manufacturing companies employed a
total of 835 employees (mean=167, SD=83) (Figure 6.2).
911
20
27
32
0%10%20%30%40%50%60%70%80%90%
100%
Per
cent
age
Employees
Company TCompany SCompany RCompany QCompany P
Figure 6.2: Employment rate by company (Korea) Two of the companies (S & T) employed over 200 employees each. In
the Korean survey, the name of the company was not collected by the
questionnaire administrator.
6.5.2 Organising
6.5.2.1 Policy (All respondents)
Fifty per cent (50%, n=23) of the respondents (n=46) stated that their
company had an occupational health and safety policy. Of those that
had policies, the majority:
Were dated (82%, n=18),
Were signed (91%, n=21),
Were accessible (96%, n=22),
Occupational health and safety management systems in Australia and Korea
-258-
Stated the need to ensure the health and safety of all persons in
the workplace by managing the risk of work-related injury and
illness (96%, n=22), and
Advocated worker consultation and participation in all elements
of the occupational health and safety management system
(78%, n=18) (Figure 6.3).
8391
96 96
78
0102030405060708090
100
Per
cent
age
Dated
Signed
Acces
sible
Risk m
gt. ap
proac
h
Seeks
partic
ipatio
n
Figure 6.3: Occupational health and safety policy elements (All respondents)
6.5.2.2 Policy (Australia)
Table 6.4 breaks down the responses from the Australian
companies/organisations surveyed.
Occupational health and safety management systems in Australia and Korea
-259-
Table 6.4: Australia - Policy
% (n) of companies with an affirmative answer
Element (n=number of respondents )
<30 employees
≥30 employees
Total
Have an occupational health and safety policy (n=40) 33% (10) 100% (10) 50% (20) Dated (n=21) 60% (6) 100% (10) 81% (16) Signed by senior management (n=21) 80% (8) 100% (10) 91% (18) Accessible to all persons at the workplace (n=21) 90% (9) 100% (10) 95% (19) Ensure health and safety by managing the risk of injury and illness (n=21)
90% (9) 100% (10) 95% (19)
Ensure consultation and participation with workers (n=21) 80% (8) 90% (10) 86% (18)
There was a significant association between the size of the company
and the existence of an occupational health and safety policy
(c2[1]=13.3, ρ<0.0005) (Figure 6.4). All of the companies with ≥30
employees indicated that they had an occupational health and safety
policy.
33
100
0102030405060708090
100
Per
cent
age
Have policy in place
<30 employees
≥30 employees
Figure 6.4: Occupational health and safety policy by size of workforce (Australia)
6.5.2.3 Policy (Korea)
The results from the Korean respondents were essentially the same as
those overall results presented above except that the two Korean
Occupational health and safety management systems in Australia and Korea
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companies that employed >200 persons had occupational health and
safety policies and neither policy advocated employee consultation and
participation in the occupational health and safety management system
(Table 6.5).
Table 6.5: Korea - Policy
No. of companies with an affirmative answer
Element
<200 employees ≥200 employees Have an occupational health and safety policy (n=5) 0 2 Dated (n=2) 0 2 Signed by senior management (n=2) 0 2 Accessible to all persons at the workplace (n=2) 0 2 Ensure health and safety by managing the risk of injury and illness (n=2)
0 2
Ensure consultation and participation with workers (n=2) 0 0
6.5.2.4 Responsibility and accountability (All respondents)
The response to whether or not the employer had a formal system for
allocating responsibility, accountability and authority for the
development, implementation and performance of occupational health
and safety was varied across respondents (n=45). Forty two per cent
(42%. n=19)49 of the companies either had no system or had planned
but not implemented such a system (Figure 6.5).
49 Note: Because of the rounding of percentages here and elsewhere in this Chapter, not all will total to 100%.
Occupational health and safety management systems in Australia and Korea
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36
7
20
13
24
0
5
10
15
20
25
30
35
40
Perc
enta
ge o
f com
pani
es
System of responsibility & accountability
NoYes, but not implementedPartially implementedOn w ay to full implementationFully implemented
Figure 6.5: System of responsibility & accountability by degree of implementation (All respondents)
Various elements of a system of responsibility and accountability had
been implemented in workplaces. Those who indicated that the
system was fully or partially implemented indicated that the following
components of the system were in place:
A formal system that ensures that occupational health and
safety is a line management responsibility (81%, n=21). In 18%
(n=5) of the companies that indicated implementation of a full
policy, further scrutiny of the questionnaire established that a
policy had not been implemented. Hence the actual percentage
of companies with a formal system is 63% (n=28);
A formal system the ensures that all the requirements of all
relevant workplace health and safety legislation are met (70%,
n=18);
Effective arrangements are in place to identify hazards and
manage risks (63%, n=16);
Occupational health and safety management systems in Australia and Korea
-262-
An effective arrangement that provides those with occupational
health and safety responsibilities with the appropriate resources
necessary to perform their functions properly (77%, n=20); and
Senior management receives regular reports of the
performance of the occupational health and safety management
system (87%, n=23). (Further scrutiny of the questionnaire failed
to support this assumption in 1 of the cases.)
The degree of implementation of a range of elements across all
workplaces as reported in the questionnaire is presented in Figure 6.6.
(This includes responses from some of the respondents who answered
that a system of responsibility and accountability had not been
implemented even in part but indicated that some of the elements of
such a system had, in fact, been implemented.)
59
67
83
67
52
0
10
20
30
40
50
60
70
80
90
Perc
enta
ge o
f com
pani
es w
ith
elem
ents
impl
emen
ted
System of responsibility & accountability elements
Line management responsibilityLegislative requirements metRisks identif ied and managedResourcesReports to management
Figure 6.6: Progress towards implementation of a system of responsibility & accountability (All respondents)
6.5.2.5 Responsibility and Accountability (Australia)
Results from the Australian participants are summarised in Table 6.6.
Occupational health and safety management systems in Australia and Korea
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Table 6.6: Australia - Responsibility and accountability
% (n)of companies with an affirmative answer
Element (n=number of responses)
<30 employees
≥30 employees
Total
Fully implemented a system of responsibility and accountability (n=40)
20% (6) 50% (5) 28% (11)
OHS is a line management responsibility (n=40) 40% (12) 90% (9) 53% (21) System ensures legislative requirements are met (n=40) 60% (18) 80% (8) 65% (26) Arrangements in place to identify hazards and manage risks (n=40)
93% (28) 90% (9) 93% (37)
Adequate resources to those with OHS responsibilities (n=39)
72%(19) 90% (9) 77% (28)
Regular reports to senior management (n=38) 43% (12) 80% (8) 53% (20)
A difference was noted in the proportion of workplaces which had
implemented a system of responsibility and accountability depending
on the size of the workplace. Although this relationship was not able to
be tested statistically because of the small sample size, it is noted that
67% (n=20) of workplaces with <30 employees indicated that had not
begun to implement such a system whereas 50% (n=5) of larger
workplaces indicated that the system was fully implemented.
6.5.2.6 Responsibility and Accountability (Korea)
Two (2) of the Korean respondents indicated that the implementation of
a formal system for allocating responsibility, accountability and
authority for the development, implementation and performance of
occupational health and safety had commenced. The other 3
workplaces indicated that there were no plans to implement such a
system (Table 6.7).
Table 6.7: Korea – Responsibility and accountability
No. of companies with an affirmative answer
Element (n=5)
<200 employees ≥200 employees Partially implemented a system of responsibility and accountability
1 1
Occupational health and safety management systems in Australia and Korea
-264-
Respondents (n=5) indicated that some elements of the system had
been implemented (Figure 6.7).
100 100
0 0
60
0
10
20
30
40
50
60
70
80
90
100P
erce
ntag
e
System of responsibility & accountability elements
Line management responsibilityLegislative requirements metRisks identified and managedResourcesReports to management
Figure 6.7: Progress towards implementation of a system of responsibility & accountability (Korea)
6.5.2.7 Competence and training (All respondents)
The existence of various elements of a system to ensure the
competency of, and provide appropriate training to, staff was
questioned. Most respondents (n=46) indicated that a rudimentary
health and safety training program had been established in their
organisation (Figure 6.8):
Health and safety training needs had been established in 72%
(n=33) of organisations; and
All staff had received appropriate workplace health and safety
training necessary for them to perform their job in 78% (n=36) of
workplaces.
Fewer respondents indicated that the following elements of a health
and safety training program had been established:
Occupational health and safety management systems in Australia and Korea
-265-
Participants are evaluated for their comprehension and retention
of training (33%, n=15);
The training program is reviewed on a regular basis (44%,
n=20); and
There is a training record signed by the trainer and all
participants (44%, n=20).
7278
33
44 44
0
10
20
30
40
50
60
70
80
Perc
enta
ge
Elements of a training program
OHS training needs identif iedAppropriate OHS training receivedComprehension & retention evaluatedTraining review ed regularlySigned record maintained
Figure 6.8: Progress towards implementation of a training program (All respondents)
6.5.2.8 Competence and Training (Australia)
Results from the Australian participants are summarised in Table 6.8.
Table 6.8: Australia - Competence and training
%(n) of companies with an affirmative answer
Element (n=40)
<30 employees
≥30 employees
Total
OHS training needs of all staff have been identified 73% (22) 70% (7) 73% (29) All staff have received appropriate OHS training 77% (23) 90% (9) 80% (32) Participants are evaluated for their comprehension and retention of training
33% (10) 50% (5) 38% (15)
Training program is reviewed on a regular basis 33% (10) 80% (8) 45% (18) Training record is signed by trainer and participants 23% (7) 80% (8) 38% (15)
Occupational health and safety management systems in Australia and Korea
-266-
An association was found between the size of the organisation and
whether or not training was reviewed on a regular basis (Fisher’s Exact
Test, c2[1]=6.6, ρ [2-sided]=0.025, ρ [1-sided]=0.013) (Figure 6.9).
33
80
0
10
20
30
40
50
60
70
80
Perc
enta
ge
Training is reviewed on a regular basis
<30 employees≥30 employees
Figure 6.9: Training review by size of organisation (Australia) Eighty per cent (80%, n=8) of larger organisations (≥30 employees) in
Queensland had a system in place to review their training program on
a regular basis.
A relationship was also found between the size of the organisation and
whether or not a training record signed by both the trainer and
participants was maintained (Fisher’s Exact Test, c2[1]=10.3, ρ [2-
sided]=0.002, ρ [1-sided]=0.002). Eighty per cent (80%, n=8) of larger
organisations (≥30 employees) maintained such a record compared
with 23% (n=7) of smaller organisations (< 30 employees) (Figure
6.10).
Occupational health and safety management systems in Australia and Korea
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23
80
01020304050607080
Perc
enta
ge
A training record is maintained and signed bythe trainer and participants
<30 employees≥30 employees
Figure 6.10: Maintenance of signed training record by size of organisation (Australia)
6.5.2.9 Competence and Training (Korea)
None of the Korean respondents indicated that the comprehension and
retention of training by participants was reviewed, but all of the
respondents indicated that a training record signed by the trainer and
participants was maintained. Four (4) of the respondents had identified
the occupational health and safety training needs of their staff and
provided appropriate training to their staff, One (1) respondent
indicated that the training program was reviewed in their organisation
on a regular basis (Table 6.9).
Table 6.9: Korea - Competence and training
No. of companies with an affirmative answer Element (n=5) <200 employees ≥200 employees Total
OHS training needs of all staff have been identified 2 2 4 All staff have received appropriate OHS training 2 2 4 Participants are evaluated for their comprehension and retention of training
0 0 0
Training program is reviewed on a regular basis 0 1 1 Training record is signed by trainer and participants 3 2 5
Occupational health and safety management systems in Australia and Korea
-268-
6.5.2.10 System documentation and communication (All respondents)
Some elements of system documentation are reviewed within the
context of the other questions presented in this section. Fifty one per
cent (51%, n=23) of respondents (n=45) indicated that they had a fully
implemented system of recording work injuries, work caused illnesses
or dangerous events. No such system was in place in 29% (n=13) of
respondent’s workplaces. The remainder had a partially implemented
system (Figure 6.11).
Eighty per cent (80%, n=36) of respondents indicated that a record of
workers who are exposed to hazardous substances is fully operational.
The system did not exist or was yet to be implemented in 20% (n=9) of
workplaces (Figure 6.11).
29
20
51
80
20
35
20
46
0%10%20%30%40%50%60%70%80%90%
100%
Per
cent
age
Record ofinjuries/illnesses,
etc. (n=45)
Record of w orkersexposed tohazardous
substances (n=45)
Communicationprocedures (n=46)
Fully implemented Partially implemented No system in place
Figure 6.11: Progress towards implementation of record and communication system (All respondents)
Respondents indicated that arrangements and procedures established
for receiving, documenting and responding appropriately to internal and
external occupational health and safety communications were fully
implemented in 35% (n=16) of workplaces and did not exist or were yet
to be implemented in 46% (n=21) of workplaces (Figure 6.11).
Occupational health and safety management systems in Australia and Korea
-269-
6.5.2.11 System documentation and Communication (Australia)
Results from the Australian participants are summarised in Table 6.10.
Table 6.10: Australia - System documentation and communication
% (n)of companies with an affirmative answer
Element (n=39)
<30 employees
≥30 employees
Total
A fully implemented system is in place to keep a record of work injuries, work caused illnesses or dangerous events
45% (14) 70% (6) 51% (20)
There is a record of workers exposed to hazardous substances
73% (22) 89% (8) 77% (30)
A fully implemented system of arrangements and procedures have been established for receiving, documenting and responding appropriately to internal and external OHS communications
30% (9) 70% (6) 40% (15)
Larger organisations (≥30 employees) were significantly more likely to
have a system fully in place for recording work injuries, work caused
illnesses or dangerous events (Fisher’s Exact Test, c2[1]=5.0, ρ [2-
sided]=0.059, ρ [1-sided]=0.032) (Figure 6.12).
30
70
0
10
20
30
40
50
60
70
Per
cent
age
Fully operational system for recording work injuries,work caused illnesses or dangerous events
<30 employees≥30 employees
Figure 6.12: Implementation of injury record system by size of organisation (Australia)
Occupational health and safety management systems in Australia and Korea
-270-
No association was found between the size of the organisation and
whether or not:
There was a record of workers who are exposed to hazardous
substances (Fisher’s Exact Test, c2[1]=0.9, ρ [2-sided]=0.654, ρ
[1-sided]=0.316); or
Arrangements and procedures had been fully established for
receiving, documenting and responding appropriately to internal
and external occupational health and safety communications
(Sample size too small to test).
6.5.2.12 System documentation and Communication (Korea)
All Korean respondents indicated that their system of record keeping
for work injuries, work caused illnesses or dangerous events was either
fully (2 workplaces) or partially (3 workplaces) operational. In contrast
none had fully established arrangements and procedures for receiving,
documenting and responding appropriately to internal and external
health and safety communications. All Korean respondents indicated
that their organisation maintained a record of workers exposed to
hazardous substances.
Table 6.11: Korea - System documentation and communication
No of companies with an affirmative answer
Element (n=5)
<200 employees ≥200 employees A fully implemented system is in place to keep a record of work injuries, work caused illnesses or dangerous events
2
There is a record of workers exposed to hazardous substances
3 2
A partially implemented system of arrangements and procedures have been established for receiving, documenting and responding appropriately to internal and external OHS communications
1
Occupational health and safety management systems in Australia and Korea
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6.5.3 Planning and implementation
6.5.3.1 System planning and objectives (All respondents)
Fifty six per cent (56%, n=26) of the respondents (n=46) indicated that
their organisation had, or was in the process of developing, a formal
occupational health and safety management system (Figure 6.13).
44
4
139
30
0
5
10
15
20
25
30
35
40
45
Per
cent
age
Is a formal Occupational Health and Safety ManagementSystem in place?
NoYes, but not implementedPartially implementedOn w ay to full implementationFully implemented
Figure 6.13: Progress towards the development of a formalised OHSMS (All respondents)
All but one of the respondents who indicated that the system was fully
implemented at their workplace (n=13) also indicated that the
objectives were communicated to all persons in the organisation, and
that they were periodically evaluated and, if necessary, updated. One
respondent was unsure of the status of the system with respect to its
contents. This same respondent was also unsure whether or not the
system established measurable objectives against which it could be
reviewed, and one respondent indicated that that their system did not.
Those respondents (n=8) who indicated that the system was still being
implemented indicated that the following elements were in place:
Occupational health and safety management systems in Australia and Korea
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Established objectives against which it may be measured (50%,
n=4);
Objectives are communicated to all persons in the organisation
(50%, n=4); and
Objectives are periodically evaluated and, if necessary, updated
(38%, n=3).
Figure 6.14 shows the elements of the occupational health and safety
management system that respondents indicated had been
implemented in their organisation.
33
54 54
0
10
20
30
40
50
60
Per
cent
age
Elements of an Occupational Health and SafetyManagement System
Measureable objectivesObjectives communicatedObjectives evaluated
Figure 6.14: Elements of OHSMS fully implemented across all organisations (All respondents)
6.5.3.2 System planning and objectives (Australia)
Results from the Australian participants are summarised in Table 6.12
Occupational health and safety management systems in Australia and Korea
-273-
Table 6.12: Australia - Planning and implementation
% (n) of companies with an affirmative answer
Element (n= number of responses)
<30 employees
≥30 employees
Total
A formal occupational health and safety management system is fully operational (n=40)
23% (7) 60% (6) 33% (13)
For organisations with fully or partially implemented systems (n=18) The system establishes measurable objectives against which it may be reviewed.
66% 9) 100% (6) 83% (15)
The objectives are communicated to all persons in the organisation.
78% (10) 89% (5) 83% (15)
The objectives are evaluated and, if necessary, updated. 78% (10) 78% (4) 78% (14)
No association (at the statistically significant value of ρ [2-sided]=0.05)
could be found between the size of the organisation and whether or not
it had a formalised occupational health and safety management system
in place (Fishers Exact Test, c2[1]=4.6, ρ [2-sided]=0.052, ρ [1-
sided]=0.042) (Figure 6.15).
23
60
0
10
20
30
40
50
60
Perc
enta
ge
Occupational Health and Safety ManagementSystem fully operational
<30 employees≥30 employees
Figure 6.15: Implementation of OHSMS by size of organisation (Australia) Similarly no association could be found between the size of the
organisation and whether or not the objectives were:
Occupational health and safety management systems in Australia and Korea
-274-
Communicated to all persons in the organisation (Fishers Exact
Test, c2[1]=0.4, ρ [2-sided]=0.603, ρ [1-sided]=0.500); or
Periodically evaluated and, if necessary, updated (Fishers Exact
Test, c2[1]=0.0, ρ [2-sided]=1.000, ρ [1-sided]=0.712)
6.5.3.3 System planning and objectives (Korea)
One of the Korean respondents indicated that the organisation had a
formal occupational health and safety management system in place.
However, none of the respondents indicated that the system had:
Measurable objectives against which it could be reviewed; or
Objectives which were communicated to all persons in the
organisation.
The respondent who indicated that the organisation had a system in
place also indicated that the objectives were periodically evaluated
and, if necessary, updated (Table 6.13).
Table 6.13: Korea - Planning and implementation
No. of companies with an affirmative answer
Element (n=5)
<200 employees ≥200 employees A formal occupational health and safety management system is fully or partially operational
3 2
The system establishes measurable objectives against which it may be reviewed.
0 0
The objectives are communicated to all persons in the organisation.
0 0
The objectives are evaluated and, if necessary, updated. 0 1
6.5.3.4 Hazard prevention (All respondents)
Respondents (n=46) indicated that organisations used a variety of
hazard identification systems but tended to rely on workplace
inspections as the main tool (Figure 6.16).
Occupational health and safety management systems in Australia and Korea
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78
54
2428
44
22
0
10
20
30
40
50
60
70
80
Per
cent
age
Hazard identification methods
Workplace inspectionsWork discussionsIndependent auditsHazard reportingJob analysis/observarionOther
Figure 6.16: Rate of use of different hazard identification methods (All respondents)
However, when those 78% (n=36) of respondents who indicated that
workplace inspections were used to identify hazards in their workplace
were later asked whether there was a system of regular inspection of
work systems, premises, plant and equipment at their workplace 92%
(n=33) responded that there was. Conversely, 80% (n=7) of
respondents who did not indicate that workplace inspections were used
in their workplace to identify hazards indicated later that there was a
regular system of inspections.
Ninety one per cent (91%, n=42) of respondents indicated that once
identified, risks in their workplace are assessed and prioritised for
corrective action.
Other hazard identification systems participants reported using
included: diligent employees (1); air monitoring (5); blood testing (1);
and risk assessment (3).
6.5.3.5 Hazard Prevention (Australia)
Results from the Australian participants are summarised in Table 6.14.
Occupational health and safety management systems in Australia and Korea
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Table 6.14: Australia - Hazard prevention
% of companies with an affirmative answer Element (n=40) <30 employees
≥30 employees
Total
Workplace inspections 80% (24) 100% (10) 85% (34) Formal/informal work discussions 53% (16) 80% (8) 60% (24) Independent audits 20% (6) 40% (4) 25% (10) Hazard reporting systems 13% (4) 80% (8) 30% (12)
Job analysis/observation 40% (12) 50% (5) 43% (17) Once identified risks are analysed and prioritised for corrective action
100% (30) 90% (9) 97.5% (39)
An association was found between the size of the organisation and
whether or not they used hazard reporting systems as a method of
identifying hazards (Fisher’s Exact Test, c2[1]=15.9, ρ [2-
sided]<0.0005, ρ [1-sided]<0.0005). Five (5) of the larger organisations
(≥30 employees) used a hazard reporting system as a method of
identifying hazards (Figure 6.17).
No association was found between the size of an organisation and
most of the hazard identification system used:
workplace inspections (Fisher’s Exact Test, c2[1]=2.3, ρ [2-
sided]=0.307, ρ [1-sided]=0.155);
formal/informal work discussions (Fisher’s Exact Test,
c2[1]=2.2, ρ [2-sided]=0.263, ρ [1-sided]=0.131), independent
audits (Fisher’s Exact Test, c2[1]=1.6, ρ [2-sided]=1.000, ρ [1-
sided]=0.950); or
job analysis/observation (Fisher’s Exact Test, c2[1]=0.3, ρ [2-
sided]=1.000, ρ [1-sided]=0.822).
Occupational health and safety management systems in Australia and Korea
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13
80
0
10
20
30
40
50
60
70
80
Per
cent
age
A hazard reporting system is used to identifyhazards in the workplace
<30 employees≥30 employees
Figure 6.17: Use of hazard reporting system by size of workplace (Australia) No association was found between company size and whether or not
risks in the workplace were assessed and prioritised for action (Fisher’s
Exact Test, c2[1]=3.1, ρ [2-sided]=0.250, ρ [1-sided]=0.250).
6.5.3.6 Hazard Prevention (Korea)
The respondents indicated that their Korean organisations made very
little use of hazard identification systems. Workplace inspections and
independent audits were used in one workplace to identify hazards,
and job analysis/observation was used in two workplaces. All Korean
respondents indicated that their workplace used air monitoring as a
method of hazard identification and all Korean respondents indicated
that a hazard reporting system existed.
The 2 larger Korean organisations (≥ 200 employees) indicated that,
once identified, risks were prioritised for action.
Occupational health and safety management systems in Australia and Korea
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Table 6.15: Korea - Hazard prevention
No. of companies with an affirmative answer
Element (n=5)
<200 employees ≥200 employees Workplace inspections 0 1 Formal/informal work discussions 0 1 Independent audits 0 1 Hazard reporting systems 3 2 Job analysis/observation 1 1 Once identified risks are analysed and prioritised for corrective action
0 2
6.5.4 Emergency prevention and management (All respondents)
In response to the question seeking information on whether or not
organisations had emergency prevention, preparedness and response
arrangements documented and maintained, 55% of respondents
(n=46) indicated that they did not or that the system was not
implemented (Figure 6.18).
48
72
11
33
0
510
15
2025
3035
40
4550
Per
cent
age
Documentation and maintenance of emergencymanagement system
NoYes, but not implementedPartially implementedOn w ay to full implementationFully implemented
Figure 6.18: Progress towards implementation of emergency management system (All respondents)
Of those who indicated that they had the system either partially or fully
implemented (n=24):
Occupational health and safety management systems in Australia and Korea
-279-
91% (n=22) indicated that the system allocated responsibility of
contacting relevant authorities (fire, ambulance, etc.); and
55% (n=13) indicated that the system was tested and evaluated
on a regular basis.
In addition, 2 respondents, who indicated that the emergency
prevention, preparedness and response arrangements in their
organisation were not document and maintained, indicated that
responsibility was allocated for contacting relevant authorities. Overall,
50% (n=23) of respondents indicated that their organisation had
allocated responsibility for contacting relevant authorities.
6.5.4.1 Emergency Prevention and Management (Australia)
Results from the Australian participants are summarised in Table 6.16.
Table 6.16: Australia - Emergency prevention management
% (n) of companies with an affirmative answer
Element (n= number of responses)
<30 employees
≥30 employees
Total
Emergency prevention, preparedness and response arrangements fully documented and maintained (n=40)
27% (8) 70% (7) 38% (15)
For organisations with system in place (n=15) Responsibility for contacting relevant authorities allocated 100% (8) 100% (7) 100% (15) System is tested and evaluated on a regular basis 63% (5) 86% (6) 73% (11)
An association was found between the size of an organisation and
whether or not it had documented and maintained emergency
prevention, preparedness and response arrangements (Fisher’s Exact
Test, c2[1]=6.0, ρ [2-sided]= 0.024, ρ [1-sided]= 0.020). Seventy per
cent (70%, n=7) of larger organisations (>30 employees) had fully
documented and maintained systems (Figure 6.19).
Occupational health and safety management systems in Australia and Korea
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27
70
0
10
20
30
40
50
60
70
Per
cent
age
Fully operational emergency management system
<30 employees≥30 employees
Figure 6.19: Documentation and maintenance of emergency management system by size of organisation (Australia)
6.5.4.2 Emergency Prevention and Management (Korea)
None of the respondents from Korean organisations indicated that their
organisations had a documented and maintained emergency
management system. The respondents (n=2) from the larger
organisations (>200 employees) indicated that they had partially
implemented such a system. However, 4 of the Korean respondents
indicated that their organisation had allocated responsibility for
contacting relevant authorities (1 did not respond). The same
respondents also indicated that the emergency response system was
not tested and evaluated on a regular basis (Table 6.17).
Table 6.17: Korea - Emergency prevention management
No. of companies with an affirmative answer
Element (n=4)
<200 employees ≥200 employees Emergency prevention, preparedness and response arrangements fully documented and maintained
0 2
Responsibility for contacting relevant authorities allocated 2 2 System is tested and evaluated on a regular basis 0 0
Occupational health and safety management systems in Australia and Korea
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6.5.4.3 Procurement and contracting (All respondents)
A range of questions explored organisations’ systems for managing
health and safety with respect to purchases. Respondents (n=40)
indicated that compliance with health and safety requirements was part
of the purchasing or leasing specifications of 37% (n=15) of
respondents’ companies. A number of respondents (19) from smaller
companies noted on their questionnaire that this question was not
applicable to their organisation; however as all organisations purchase
products this response has been interpreted as these purchasing
controls not being in place.
Contractor management was an issue for 57% (n=23) of the
companies. Of these companies, 73% (n=29) required contractors to
meet the health and safety standards set by the company and 62%
(n=25) regularly monitor the workplace health and safety of contractor
activities on site.
6.5.4.4 Procurement and Contracting (Australia)
Results from the Australian participants are summarised in Table 6.18.
Table 6.18: Australia - Procurement and contracting
% (n) of companies with an affirmative answer
Element (n=40)
<30 employees
≥30 employees
Total
Health and safety requirements are incorporated into purchasing or leasing specifications
23% (7) 80% (8) 38% (15)
Contractors are required to meet occupational health and safety requirements
30% (11) 80% (6) 43% (17)
Contractor activity on site is regularly monitored 23% (7) 60% (6) 33% (13)
With the inclusion of those respondents who indicated that the question
on purchasing controls was not relevant to their organisation as
indicated above, an association was found between the size of the
company and whether or not it had established procedures to ensure
compliance with health and safety requirements were incorporated into
Occupational health and safety management systems in Australia and Korea
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purchasing or leasing requirements (Fisher’s Exact Test, c2[1]=10.28,
ρ [2-sided]=0.002, ρ [1-sided]=0.002). Larger organisations (≥30
employees) were more likely to have these procedures in place than
smaller organisations (<30 employees; 80%, n=8 and 23%, n=7
respectively).
No association was found between the size of the organisation and
whether or not contractors were:
Required to meet the health and safety standard set by the
company (Fisher’s Exact Test, c2[1]=0.19, ρ [2-sided]=1.000, ρ
[1-sided]=0.579); or
Regularly monitored on site for their workplace health and
safety activities (Fisher’s Exact Test, c2[1]=0.02, ρ [1-
sided]=0.002, ρ [2-sided]=0.630).
6.5.4.5 Procurement and Contracting (Korea)
Respondents from the 2 larger Korean organisations (>200
employees) indicated that their organisations had established
procedures to ensure compliance with health and safety requirements
are incorporated into purchasing or leasing requirements. One of
these respondents also indicated that contractors in the company were
required to meet health and safety standards set by the company. No
other respondent indicated that their company had implemented this
requirement and none of the companies regularly monitored the
workplace health and safety performance of contractor activities on
site.
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Table 6.19: Korea - Procurement and contracting
No. of companies with an affirmative answer
Element (n=5)
<200 employees ≥200 employees Health and safety requirements are incorporated into purchasing or leasing specifications
0 2
Contractors are required to meet occupational health and safety requirements
0 1
Contractor activity on site is regularly monitored 0 0
6.5.5 Evaluation
6.5.5.1 Performance monitoring and measurement (All respondents)
Both proactive and reactive forms of evaluation of workplace health
and safety evaluation were investigated.
Respondents (n=46) indicated that companies used a variety of
methods to monitor occupational health and safety performance in their
workplaces. The most popular methods were reactive measures:
Work-related injuries, 69% (n=32);
Work-related illnesses, 58% (n=27);
Workers’ compensation records 56% (n=26), and
To a lessor extent, property losses, 16% (n=7).
The most popular of the proactive measures used to monitor health
and safety performance was prevention and control measures (38%,
n=17) (Figure 6.20). Other proactive measures used to measure
health and safety performance were:
Work-related incidents that could have caused injury or damage
under slightly different circumstances (near misses), 33%
(n=15);
Hazard identification activities, 42% (n=19); and
Occupational health and safety management systems in Australia and Korea
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Individual’s occupational health and safety performance criteria,
13% (n=6).
No performance measures were used by 11% (n=5) of the
respondents.
The measures used by companies were grouped into reactive and
proactive measures and a count given to the number of respective
measures used by each company. Organisations were significantly
more likely to use reactive measures of performance than proactive
measures when tested using the Wilcoxon signed ranks test (Z=-2.762
ρ=0.006).
Wor
k-re
late
d in
jurie
s, 6
9%
Wor
k-re
late
d illn
esse
s, 5
8%
Wor
k C
omp
, 56%
Haz
ard
ID, 4
2%
P&C
act
ivitie
s, 3
8%
Nea
r mis
ses,
33%
Prop
erty
loss
es, 1
6%
Indi
vidu
als'
Per
form
ance
, 13
%
0
10
20
30
40
50
60
70
Per
cent
age
of o
rgan
isat
ions
us
ing
the
mea
sure
Proactive and reactive measures used to evaluateperformance
Proactive measures
Reactive measures
Figure 6.20: Use of proactive and reactive measures to evaluate performance (All respondents)
6.5.5.2 Performance monitoring and measurement (Australia)
Results from the Australian participants are summarised in Table 6.20.
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Table 6.20: Australia – Performance monitoring and measurement
% (n) of companies with an affirmative answer
Element (n=39)
<30 employees ≥30 employees Total Work related injuries 55% (16) 90% (9) 64% (25) Work-related illnesses 45% (13) 70% (7) 51% (20) Workers compensation records 38% (11) 90% (9) 51% (20) Hazard identification activities 38% (11) 60% (6) 44% (17) Prevention & control activities 35% (10) 30% (3) 33% (13) Work-related incidents that could have caused injury or damage under slightly different circumstances (near misses)
28% (8) 60% (6) 36% (14)
Property losses 7% (2) 40% (4) 15% (6) Individuals’ OHS performance criteria 10% (3) 30% (3) 15% (6)
Company size was however found to be associated with the use of:
workers’ compensation records (Fisher’s Exact Test, c2[1]=8.1,
ρ [2-sided]=0.008, ρ [1-sided]=0.005); and
property losses (Fisher’s Exact Test, c2[1]=6.3, ρ [2-
sided]=0.028, ρ [1-sided]=0.028).
Larger organisations were more likely to use these measures than
smaller organisations (Table 6.20).
No statistically significant association was found using Fisher’s Exact
Test between the size of the organisation and the use of the following
tools to evaluate occupational health and safety performance:
Work-related injuries (c2[1]=3.9, ρ [2-sided]=0.064, ρ [1-
sided]=0.050);
Work-related illnesses (c2[1]=1.9, ρ [2-sided]=0.273, ρ [1-
sided]=0.157);
Prevention and control activities (c2[1]=1.5, ρ [2-sided]=0.282, ρ
[1-sided]=0.199);
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Work-related incidents that could have caused injury or damage
under slightly different circumstances (near misses) (c2[1]=3.4,
ρ [2-sided]=0.124, ρ [1-sided]=0.074); or
Individuals’ occupational health and safety performance criteria
(c2[1]=2.2, ρ [2-sided]=0.163, ρ [1-sided]=0.163).
Of the Australian organisations, 48% (n=19) used a mixture of both
proactive and reactive measures, 15% (n=6) used proactive measures
only, 25% (n=10) used reactive measures only, and 13% (n=5) did not
use any performance measures.
6.5.5.3 Performance monitoring and measurement (Korea)
All of the Korean companies made use of work-related injuries and
illnesses, and workers’ compensation records as occupational health
and safety performance measures. None of the Korean companies
made use of near misses, property losses, or individuals’ performance
criteria as performance measures. One of the larger companies (>200
employees) made use of hazard identification activities as a
performance measure and three of the companies used prevention and
control activities as a performance measure (Table 6.21).
Table 6.21: Korea – Performance monitoring and measurement
No. of companies with an affirmative answer
Element (n=5)
<200 employees ≥200 employees Work related injuries 3 2 Work-related illnesses 3 2 Workers compensation records 3 2 Hazard identification activities 0 1 Prevention & control activities 2 1 Work-related incidents that could have caused injury or damage under slightly different circumstances (near misses)
0 0
Property losses 0 0 Individuals’ OHS performance criteria 0 0
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6.5.5.4 Other active and reactive measures (All respondents)
A number of active and reactive performance measures were
examined in more detail. (Some of these measures e.g. workplace
inspections) have already been presented in this section.)
Respondents (n=46) indicated that 93% (n=43) of the companies used
active (a regular program of environmental and personal monitoring)
and/or reactive (monitoring in response to complaints only) monitoring
of workers exposure to hazardous substances (Figure 6.21). Seven
per cent (7%, n=3) of respondents indicated that no monitoring was
necessary as there was no exposure.
67
9
17
0
20
40
60
80
100
Per
cent
age
Use of active and reactive monitoringactivities for hazardous substance exposure
BothReactiveProactive
93%
Figure 6.21: Monitoring methods used to identify workers' exposure to hazardous substances (All respondents)
Another active monitoring system is health surveillance. Of the 46
respondents 83% (n=38) indicated that their workplace had a health
surveillance program for workers who were exposed to mercury or
were in lead-risk jobs, as appropriate. However the frequency of
testing for the level of contaminants in the blood of exposed workers
among those who indicated that they undertook health surveillance
(n=39) varied considerably (Figure 6.22).
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54
26
83 3
8
0
10
20
30
40
50
60
Per
cent
age
6 monthlyAnnually
2 years3 years
When symptoms reported
As required by designated doctor
Figure 6.22: Frequency of blood tests (All respondents)
6.5.5.5 Other active and reactive measures (Australia and Korea)
The frequency of health surveillance and air monitoring for
contaminants in the Australian workplaces is shown in Table 6.22.
Table 6.22: Australia - Health surveillance and air monitoring
%(n) of companies with an affirmative answer
Element (n=40)
<30 employees
≥30 employees
Total
A health surveillance program is in place 80% (24) 80% (8) 80% (32) Workers exposure to hazardous substances are measured by: A regular program of environmental and personal (proactive) monitoring
70% (21) 50% (5) 65% (26)
Monitoring in response to complaints only (reactive) 10% (3) 10% (1) 10% (4) Both proactive and reactive monitoring 13% (4) 30% (3) 18% (7)
In the past 12 months respondents from Australian lead-risk firms
indicated that health surveillance had been arranged for 232 workers.
Korean respondents did not provide any details of the number of
workers tested in the last 12 months and the Oral Health Service did
not arrange any health surveillance for mercury exposed workers in the
past 12 months.
Occupational health and safety management systems in Australia and Korea
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A reactive measure of occupational health and safety performance is
the number of adverse outcomes from the monitoring. Respondents
indicated that 2 (1%) of the 232 workers for whom health surveillance
had been arranged had presented with signs and symptoms consistent
with lead poisoning in the past 12 months.
Workers in 4 of the Korean workplaces had presented with signs and
symptoms consistent with mercury poisoning in the past 12 months
(0.5% of Korean workforce in the companies which responded).
In addition, respondents indicated that 3 male workers from the
Australian lead-risk workplaces (1% of workers undergoing health
surveillance) were removed from the job because of an elevated blood
lead level in the past 12 months. In the 4 Korean workplaces from
which respondents provided information 11 male workers (2% of the
workforce from these workplaces) were removed from the workplace
because of an elevated blood mercury level in the 12 months prior to
the completion of the survey.
6.5.5.6 Investigation of accidents (All respondents)
The investigation of work–related injuries, ill health, diseases and
incidents can be used to identify failures in occupational health and
safety management systems. Eighty per cent 80% (n=37) of
respondents (n=46) indicated that all accidents are investigated at their
workplace and 56% (n=27) of respondents indicated that the results of
accident investigations are documented.
In workplaces (n=37) where all accidents are investigated, 65% (n=24)
of respondents indicated that the results are documented.
The reasons respondents50 (n=44) indicated for the investigation of
accidents at workplaces varied:
50 Note: The number of respondents to these questions exceeds the 37 who responded that “all” accidents were investigated as this group includes cases where “some” accidents are investigated.
Occupational health and safety management systems in Australia and Korea
-290-
Identify the immediate causes of the accident, 71% (n=31);
Identify those at fault51, 27% (n=12);
Identify any failures in the occupational health and safety
management system, 50% (n=22);
Prevent similar occurrences in the future, 84% (n=37).
6.5.5.7 Investigation of accidents (Australia)
Results from the Australian participants are summarised in Table 6.23.
Table 6.23: Australia - Investigation of accidents
% (n) of companies with an affirmative answer Element (n= number of responses) <30 employees ≥30
employees Total
All accidents are investigated (n=40) 83% (25) 90% (9) 85% (34) Accidents are investigated to (n=38): Determine immediate causes 64% (18) 100% (10) 74% (28) Identify those at fault 39% (11) 10% (1) 32% (12) Identify any failures in the OHS management system 43% (12) 90% (9) 55% (21) Prevent similar occurrences in the future 89% (25) 100% (10) 92% (35)
Using Fisher’s Exact Test, a statistically significant difference was
found in the proportion of smaller and larger organisations which
investigated accidents to:
Determine the immediate causes (c2[1]=4.8, ρ [2-sided]=0.038,
ρ [1-sided]=0.028); and
Identify any failures in the occupational health and safety
management system (c2[1]=6.6, ρ [2-sided]=0.012, ρ [1-
sided]=0.011).
51 Modern occupational health and safety practice opposes the apportioning of blame (fault) in preference for preventing a recurrence. This question therefore tests a negative outcome.
Occupational health and safety management systems in Australia and Korea
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6.5.5.8 Investigation of accidents (Korea)
Of the Korean respondents 2 indicated that all accidents were
investigated and 3 that the results were documented. Two (2) of the
organisations indicated that the reason accidents were investigated
was to identify the immediate cause. One (1) respondent, from one of
the smaller organisations (<200 employees), indicated that a further
reason was to identify any failures in the health and safety
management system and 3 indicated that a further reason was to
prevent similar occurrence in the future (Table 6.24).
Table 6.24: Korea - Investigation of accidents
No. of companies with an affirmative answer Element (n=5) <200 employees ≥200 employees
All accidents are investigated 1 1 Accidents are investigated to: Determine immediate causes 1 1 Identify those at fault 0 0 Identify any failures in the OHS management system 1 0 Prevent similar occurrences in the future 2 1
6.5.5.9 Audit (All respondents)
Audits to evaluate the performance of the occupational health and
safety management system were a regular occurrence in 58% (n=14)
of those workplaces (n=24) that indicated that they had an occupational
health and safety management system partially or fully implemented.
Three (3) respondents who indicated that their organisation had no
occupational health and safety management system also indicated that
regular audits were conducted to evaluate the system. These three
responses have been deleted from the following data.
The frequency of audits varied across these workplaces (Figure 6.23).
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10
43
29
19
0
5
10
15
20
25
30
35
40
45
Perc
enta
ge
6 monthly Annually 2 yearly Other
Figure 6.23: Frequency of audits (All respondents) Those who indicated “Other” indicated that audits were held 3 monthly
or as required.
Thirty one per cent 31% (n=4) of the audits were audits by internal
personnel, 13% (n=2) by external personnel, and 57% (8) were a
combination of internal and external audits.
The audits frameworks used as the benchmark against which the
company’s performance was evaluated included:
a company standard, 57% (n=8);
AS/NZS 4801 (Standards Australia/Standards New Zealand:
2001), 21% (n=3);
some other standard, 21% (n=3).
6.5.5.10 Audits (Australia)
Results from the Australian participants, with respect to those who had
an occupational health and safety management system only, are
summarised in Table 6.25
Occupational health and safety management systems in Australia and Korea
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Table 6.25: Australia - Audit program
% of companies with an affirmative answer Element (n= number of responses) <30 employees
≥30 employees
Total
There is a regular system of audits to evaluate the performance of the OHS management system (n=17)
57% (4) 89% (8) 72% (12)
Audits are conducted (n=15) Never 0% 0% 0% 6 monthly 0% 25% (2) 13% (2) Annually 86% (6) 38% (3) 60% (9) Every 2 years 0% 25% (2) 13% (2) Other 14% (1) 13% (1) 13% (2) Audits are conducted by (n=14) internal personnel 0% 38% (3) 21% (3) external personnel 17% (1) 13% (1) 14% (2) both internal and external personnel 83% (5) 50% (4) 64% (9) Audits are conducted to (n=13) To OHSMS 4801 standard 17% (1) 29% (2) 23% (3) To the Company standard 83% (5) 43% (3) 62% (8) Other standard 0% 29% (2) 15% (2)
No significant association was found between the size of the company
and whether or not it had a regular system of audits to evaluate the
performance of its occupational health and safety management
system.
6.5.5.11 Audits (Korea)
One (1) of the Korean companies indicated that it used a regular
system of audits to evaluate the performance of its occupational health
and safety management system. The audits were conducted by
internal personnel but the respondent was unsure of the frequency of
the audits or of the standard used to evaluate performance. Other
organisations, although they indicated that they did not use a regular
system of audits, did respond to the questions on the frequency of
audits and the other related questions. None of the respondents
indicated the standard to which audits were conducted. All responses
to the other questions are shown in Table 6.26.
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Table 6.26: Korea - Audit program
No. of companies with an affirmative answer
Element (n= 5)
<200 employees ≥200 employees There is a regular system of audits to evaluate the performance of the OHS management system
0 1
Audits are conducted: Every 2 years 3 1 Audits are conducted by: internal personnel 1 1
6.5.5.12 Management review (All respondents)
For those companies that reported either having or developing an
occupational health and safety management system (n=24), the period
between management reviews varied considerably (Figure 6.24).
9
1
48
9
17
4
05
101520253035404550
Perc
enta
ge
Never 6 monthly Annually 2 yearly Whenw ork-related
symptomsare
reported
Other
Figure 6.24: Frequency of management review of OHSMS (All respondents) Of the Korean companies, 4 reported that their system was reviewed
by management when work-related symptoms are reported and 1
responded that the system was never reviewed.
Occupational health and safety management systems in Australia and Korea
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6.5.6 Oral Health Service
As the exposure study to mercury among Oral Health workers was
conducted within a single organisation, the results of the survey of OHS
management systems in this organisation are presented below (Table
6.27):
Occupational health and safety management systems in Australia and Korea
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Table 6.27: Summary of Oral Health Service responses
Policy A written occupational health and safety policy that is dated, signed by senior management and readily accessible to all persons in the workplace. A policy that states the need to ensure the health and safety or all persons at the workplace by managing the risk of injury and work caused illness and the need for workers and their representatives to be consulted and encouraged to actively participate in all elements of the occupational health and safety management system. Organising Fully implemented a system for allocating responsibility and authority for the development, implementation and performance of occupational health and safety that ensure that occupational health and safety is a line management responsibility. A formal system established that ensures that the requirements of all workplace health and safety legislation are met. Effective arrangements in place to ensure that persons with occupational health and safety responsibilities have the appropriate resources to perform their functions effectively. Effective arrangements in place to identify hazards and manage risks Identified the occupational health and safety training needs of all staff and provided them with the appropriate health and safety training necessary to perform their job. A training program that is reviewed on a regular basis and maintains a training record signed by the trainer and participants. Fully implemented arrangements and procedures for receiving, documenting and responding appropriately to internal and external occupational health and safety communications Planning and implementation A fully documented occupational health and safety management system that established measurable objectives against which it may be reviewed. Communicated the objectives to all persons in the organisation and periodically evaluates and, if necessary, updates the objectives. Uses workplace inspections, formal internal work discussions, hazard reposting systems, and job analysis/observation to identify hazards. A process whereby once identified, risks in the workplace are assessed and prioritised for corrective action. Fully documented and maintains emergency prevention, preparedness and response arrangements that allocates responsibility for contacting relevant authorities and is tested and evaluated on a regular basis. Procedures established to ensure compliance with health and safety requirements are incorporated into purchasing and leasing specifications. Requires that contractors meet health and safety standards set by the company and regularly monitors the workplace health and safety performance of contractor activities on site. Hazard prevention A system of proactive and reactive monitoring of workers’ exposures to hazardous substances. A system of regular inspections of work systems, premises, plant and equipment. A health surveillance program for workers in mercury-risk jobs. Evaluation Monitors and reports on work-related injuries and illnesses, near misses property losses, workers’ compensation records, and hazard identification activities as indicators of health and safety performance in the workplace. All accidents investigated to identify the immediate cause of the accident, those at fault, any failures in the occupational health and safety management system and to prevent similar occurrences in the future. A process for the documentation of the results of accident investigations. A system of regular audits to evaluate the performance of the occupational health and safety management system conducted 6 monthly by internal personnel.
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6.6 Discussion
6.6.1 Occupational health and safety management system
Neither Australian nor Korean workplaces are required by legislation to
have occupational health and safety management systems. However,
the series of obligations set out in Australian legislation and the risk
management approach required by the legislation should be easier to
administer in the workplace if an occupational health and safety
management system is in place. The Korean legislative system on the
other hand places an emphasis on regulating particular activities within
the workplace but does contain a number of requirements, such as the
appointment of Safety and Health Officers, and Inspection Officers, and
monitoring and health surveillance activities, which presumably would
be easier to manage with an occupational health and safety
management system in place.
Overall 58% of organisations indicated that they had either
commenced to implement a formalised occupational health and safety
management system or had already fully implemented one. Among
Australian firms 33%, including 23% of smaller organisations (<30
employees) had a fully implemented system. The rate of
implementation among smaller organisations is approximately 40% of
that of larger organisations (≥30 employees). This finding supports the
anecdotal evidence by (Gallagher, 1997) that smaller organisations are
less likely to have occupational health and safety management
systems but is also an indication that smaller organisations need not be
excluded from this process.
One (1) of the 5 Korean organisations had a formal occupational health
and safety management system in place. The other organisations
indicated that they had part of the system implemented. However, in
response to further questions it is apparent that the development of the
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system is following along different lines to that of the Australian firms
surveyed (Table 6.28).
Table 6.28: Australia vs. Korea - Implementation of OHS management system
Element Australia Korea The system establishes measurable objectives against which it may be evaluated
83% 0%
The objectives are communicated to all persons in the organisation 83% 0% The objectives are evaluated and, if necessary, updated 78% 25%
From this data it would appear that, based on the requirements of the
Guidelines on occupational safety and health management systems
(International Labour Office, 2001), which places a lot of importance on
having measurable objectives, the Australian companies surveyed
have a more advanced approach to the development of occupational
health and safety management systems when compared with the
Korean companies surveyed.
The differences could also be explained by a difference in interpretation
of what comprises an occupational health and safety management
system. Chapter II of the Korean Industrial Safety and Health Act
(1996) is headed Safety and Health Management System. This
section of the legislation sets out some occupational health and safety
responsibilities for personnel in Korean organisations. These
responsibilities are extremely limited in comparison with the Guidelines
on occupational safety and health management systems (International
Labour Office, 2001). If the Korean respondents were referring to
whether or not they had implemented the requirements of this section
of the legislation, the low positive response rate to related questions is
explained.
6.6.1.1 Responsibility and accountability
The Guidelines on occupational safety and health management
systems recognises the importance of having a formal system for
allocating responsibility and authority for the development,
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implementation and performance of occupational health and safety
(International Labour Office, 2001): 7-8). This is a factor that has been
found to be characteristic of companies with exemplary health and
safety performance (Cohen & Cleveland, 1983) (Viner & VIOHS,
1989). Forty seven per cent (47%) of respondents had partially or fully
implemented a system of responsibility and accountability. However, it
was noted that 18% of those that indicated that they had fully
implemented such a system also indicated that the system did not
ensure that health and safety is a line management responsibility.
A difference between the approaches to this is evident in the response
of the Australian and Korean organisations surveyed (Table 6.29).
Table 6.29: Australia vs. Korea - Responsibility and accountability
Element Australia Korea OHS established as a line management responsibility 53% 100% System ensures legislative requirements are met 65% 100% Arrangements in place to identify hazards and manage risks 93% 0% Adequate resources to those with OHS responsibilities 77% 0% Regular reports to senior management 53% 60%
One possible reason for these differences is that Korean legislation
clearly establishes occupational health and safety as a line
management responsibility. This is reinforced by the requirements in
the Industrial Safety and Health Act 1996 (Korea) to appoint
Occupational Health and Safety Management Officers in certain
circumstances which would include all Korean organisations covered in
this survey. The Workplace Health and Safety Act 1995 (Qld) also
establishes health and safety as a line management responsibility but
the obligation may be less clear as it exists in the context of the
obligations of a large range of persons who interact with the workplace.
Workplace Health and Safety Officers must also be appointed under
this Act but only in workplaces that normally employ 30 or more
persons. It is notable that 90% of these larger workplaces recognised
Occupational health and safety management systems in Australia and Korea
-300-
health and safety as a line management responsibility compared with
20% of smaller workplaces.
Another interesting difference in the above table is with the provision of
adequate resources to those with occupational health and safety
responsibilities. This is a requirement of the Industrial Safety and
Health Act 1996 (Korea) but is not a requirement of the Workplace
Health and Safety Act 1995 (Qld). Possible reasons why Queensland
organisations appear more likely to provide these resources than the
Korean organisations surveyed include:
Although not a requirement of the Workplace Health and Safety
Act 1995 (Qld), a major requirement of this legislation is that risk
assessments be conducted of all activities. These assessments
are resource intensive and are often carried out by the
Occupational Health and Safety Officer. It is possible that the
allocation of resources is associated with this activity in
particular; and/or
The regulatory arrangements in Korea, and the resources
provided by the Korean government for health surveillance,
occupational hygiene monitoring, and other activities could lead
Korean organisations to rely on government resources and
activities rather than develop their own.
The impact of common law. Korean workers are far less likely
to sue for damages for injury under common law than Australian
workers. In Australia, the provision of adequate resources is a
factor considered in common law cases. This is also a possible
explanation for Australian workplaces being more likely to have
systems in place to identify hazards and manage risks.
6.6.1.2 Occupational health and safety policy
Although not a requirement of either the Workplace Health and Safety
Act 1995 (Qld) or the Korean Industrial Safety and Health Act 1996, the
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cornerstone upon which occupational health and safety management
systems are built is the occupational health and safety policy. The
results from Australian and Korean organisations surveyed were
essentially the same in this instance. Of the Australian companies
surveyed 50% had an occupational health and safety policy in place as
did 40% of the Korean companies surveyed. However, 100% of the
Australian companies with 30 or more employees and 100% of the
Korean companies with 200 or more employees had occupational
health and safety policies.
A number of authors point to the importance of involving workers in the
implementation of an occupational health and safety management
system and the benefits to be gained from their involvement (Cohen &
Cleveland, 1983; Painter & Smith, 1986; WorkCover, 1995). All of the
occupational health and safety management systems reviewed as part
of this study included an element advocating worker participation in the
system. The Guidelines on occupational safety and health
management systems (International Labour Office, 2001: 6) states that
“worker participation is an essential element of the OSH management
system in the organization”.
A notable difference between the policies of the Korean companies and
the Australian companies is that 88% of the latter that had occupational
health and safety policies recognised the importance of having workers
and their representatives consulted and encouraged to actively
participate in all elements of the occupational health and safety
management system. None of the Korean companies included this
element. A possible reason for this difference is that one of the critical
factors that lead to changes in Australian legislation in the 1980s was a
strong, rank and file lead health and safety movement by workers.
Requirements for consultation and participation of workers are included
in the Workplace Health and Safety Act 1996 (Qld). Although the
workers’ movement in Korea was one of the factors that influenced
Occupational health and safety management systems in Australia and Korea
-302-
change there, it was not as strong an occupational health and safety
movement as in Australia and other places.
However, Korean legislation, the Act on the Promotion of Workers
Participation and Cooperation 1997, established the requirement for
the establishment of Labor-Management Councils in which
occupational health and safety maters would be discussed52. In most
states of Australia workplaces of certain sizes are required to establish
Occupational Health and Safety Committees which review and make
recommendations to management regarding occupational health and
safety issues. Perhaps having the requirement to establish this
consultative mechanism in the Act dealing with occupational health and
safety has had greater impact on promoting worker participation in
occupational health and safety issues and makes it less likely to be
overtaken by other issues such as remuneration and general
conditions.
6.6.1.3 Competence and training
Similar percentages of both Australian and Korean organisations
surveyed had established the training needs of all staff (73% and 80%
respectively).
While similar percentages of companies in both countries had identified
the occupational health and safety training needs of their staff and
provided the appropriate training, organisations in Australia were much
more likely to evaluate and review that training.
6.6.1.4 Emergency prevention, preparedness and response
Another area of substantial difference between the organisations
surveyed in Australia and Korea related to their emergency response
plans. An emphasis on emergency management in western countries 52 In organisations of 1000 or more employees a separate Occupational Health and Safety Committee must be established (Industrial Safety and Health Act 1996 [Korea] Article 19).
Occupational health and safety management systems in Australia and Korea
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arose following the major disasters outlined in the introduction to
Chapter 2. While emphasis has been on the prevention of disasters, it
is recognised that substantial effort must also go into the minimisation
of any adverse effects that may result from workplace incidents. In
most instances, particularly with respect to adverse effects off site, this
aspect is more important for larger organisations.
It is not surprising therefore that the larger organisations surveyed in
Australia were significantly more likely to have fully documented and
maintained prevention, preparedness and response arrangements for
emergencies (70%) than smaller organisations (27%). None of the
Korean organisations surveyed had fully documented emergency
management systems.
6.6.1.5 Procurement and contracting
The Workplace Health and Safety Act 1995 (Qld) (Part 3 Division 2)
establishes clear obligations for a range of persons including
contractors, and suppliers. And, perhaps because the legislation does
not specify exactly how these obligations will be met, various
requirements have found their way into the practice of many of the
Australian organisations surveyed. Eighty per cent (80%) of larger
organisation included health and safety requirements in purchasing or
leasing specifications and require the contractors meet occupational
health and safety requirements. Korean legislation is much less
specific on the obligations of other parties (Industrial Safety and Health
Act 1996 [Korea] Article 5.2). It is notable therefore, that only the two
larger Korean organisations surveyed appeared to place any
importance on these issues. Although there are difference in the
reliance on contractors in Korea and Australia, the difference is not so
great as to be a major influence on these results.
Occupational health and safety management systems in Australia and Korea
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6.6.1.6 Evaluation
One of the characteristics of performance-based legislation such as the
Workplace Health and Safety Act 1995 (Qld) is that employers must be
able to demonstrate that they have taken the necessary precautions to
prevent workplace injury and disease. Because the legislation does
not, for the most part, specify how this is to be done, employers resort
to other methods to obtain an indication of how successful their efforts
are. Part of this involves the monitoring of outcomes, and another, the
development and auditing of occupational health and safety
management systems.
With respect to the latter of these 72% of the Australian organisations
surveyed (89% of the larger organisations) who had occupational
health and safety management systems had a regular system of audits
whereas only one (20%) of the Korean organisations had a similar
system.
In a system that relies on compliance with regulations, such as the
Korean system, it would be expected that having a system that
ensured legislative requirements were met would be more important.
As reported, 100% of the Korean organisations surveyed had this
system in place in comparison with 65% of Australian organisations
surveyed.
Other methods of evaluating performance include a system of reactive
measures such as injuries, illnesses, etc. and proactive measures
based on the actions taken to prevent injuries and illnesses such as
hazard identification and prevention and control activities. The former,
although widely criticised in the literature as being unreliable and
influenced by factors outside the workplace, have been in use for a
long period of time and are widely used. As the emphasis moves
towards prevention, it is expected that the latter measures will assume
more importance.
Occupational health and safety management systems in Australia and Korea
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This trend was evident among the Australian organisations surveyed
with the majority of measures being used being reactive but with a
substantial number of organisations using a mixture of both reactive
and proactive measures to measure performance. This trend was not
as obvious among the Korean companies surveyed.
It is interesting to note that there was a statistically significant difference
between the size of the company and the use of workers’
compensation data as a performance measure. This is to be expected
as injuries, although far too frequent on a national scale, are relatively
rare in individual workplaces. Sixty five per cent (65%) of the
Australian workplaces surveyed reported no workers’ compensation
claims in the past 12 months. This is therefore not a very useful
measure for small organisations. In fact, proactive measures may be a
more appropriate measure for smaller organisations and it is notable
that 35% of smaller organisations compared with 30% of larger
organisations used prevention and control measures as a performance
measure.
6.6.1.7 Hazard prevention and control activities
A requirement of both the Workplace Health and Safety Act 1995 (Qld)
and the Industrial Safety and Health Act 1996 (Korea) is that a record
be maintained of workers who are exposed to hazardous substances.
Seventy seven per cent (77%) of Australian respondents in contrast
with 100% of Korean respondents indicated that they kept these
records.
As all but one (1) of the Australian companies surveyed were lead-risk
workplaces and are therefore required to keep these records, it is
difficult to see why this discrepancy should exist. One possible reason
is a confusion that arises from the Workplace Health and Safety
Regulation 1997 (Qld). The Regulation (S129[7][b][i]) requires that if,
following a risk assessment, the employer assesses a job as being a
lead-risk job the chief executive of the Division of Workplace Health
Occupational health and safety management systems in Australia and Korea
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and Safety must be notified. However, one of the other requirements
(S129[7][b][ii]) is that the employer must, if possible, change the
process to one that does not include a lead-risk job. It is possible that
the workplace could remain on the list of lead-risk workplaces after the
Division was notified.
However, it is difficult to accept that this would be the situation in 23%
of the Australian cases and it must be assumed that there is not full
compliance with this requirement.
The Workplace Health and Safety Act 1995 (Qld) also requires that
employers maintain a record of work injuries and work caused illnesses
and dangerous events. Only 51% of Australian companies surveyed
had a system in place to do this. A further 17% had a system partially
implemented or planned but not implemented. Therefore, 32% of the
workplaces had no system in place. All of these latter organisations
would be in contravention of the requirements of the legislation.
In contrast 40% of the Korean organisations surveyed had a system of
record keeping for work injuries, work caused illnesses and dangerous
events in place and 40% had the system partially implemented as
required by the Enforcement Regulations for Industrial Safety and
Health Act 1997 (Korea) (Article 4).
Both the Workplace Health and Safety Act 1995 (Qld) and the
Industrial Safety and Health Act 1996 (Korea) require that, for workers
in lead-risk jobs in Queensland and exposed to mercury in Korea,
workers exposures are monitored and that blood samples be taken and
analysed on a regular basis.
A health surveillance program was in place in 82% of lead-risk
workplaces surveyed in Australia and an air monitoring program for
hazardous substances was in place in 93% of workplaces. In
comparison, 100% of the Korean workplaces surveyed had both health
surveillance and monitoring programs in place.
Occupational health and safety management systems in Australia and Korea
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It is notable that, based on data provided by the companies on the
incidence of removal of persons from the workplace because of
excessive exposure to mercury or lead, there is not a great difference
in health and safety management with respect to heavy metals in the
Korean or Australian companies surveyed. It is acknowledged that, in
the Australian case, this information may be unreliable as not all
companies were undertaking health surveillance.
Systems will not themselves eliminate OHS injury and illness nor do
they ensure compliance with legislative requirements. However, the
creation of a system within organisations certainly places them in a
much better position to control risks (Gallagher, 1992; Quinlan, 1999;
Winder, Gardner et al., 2001; Frick, Per Langaa, et al., 2002)
6.6.2 Oral Health Service
The results of the survey from the Oral Health Service show that it has
a very highly developed occupational health and safety management
system. It appears, from the information provided, to meet most of the
legislative requirements of the Workplace Health and Safety Act 1995
(Qld) and extends the management of health and safety well beyond
the confines of this legislation.
However, although the respondent indicated that a health surveillance
system for mercury exposure was in place, no health surveillance had
been conducted in the year prior to completion of the survey. Further,
although a fully implemented health and safety communication was
reported as being in place, the results of Chapter 5 indicated that this
was an area for improvement in the Oral Health Service.
6.7 Summary
The survey indicated that health and safety management system
elements had been introduced in companies in both Australia and
Korea. In general, the progress towards implementation of health and
Occupational health and safety management systems in Australia and Korea
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safety management systems in accordance with the requirements of
the Guidelines on safety and health management systems
(International Labour Office, 2001) was more advanced in Australia
than in Korea. Also, in Australia, the progress was more advanced in
companies with 30 or more employees but was not exclusive to these
companies.
Organisations in Korea with 200 or more employees were more likely
to have implemented elements of an occupational health and safety
management system than smaller companies.
The Korean companies surveyed demonstrated a greater compliance
with specific legislative requirements than did the Australian companies
surveyed. However, the Australian companies were more likely to
have implemented a broader range of hazard identification and
prevention activities beyond the narrow requirements of the legislation
than were the Korean companies. It is apparent that the performance-
based legislative approach adopted in such Australian States as
Queensland encourages a more proactive approach towards the
prevention of work-related injuries and illness than does the
prescriptive legislation of Korea. However, the Korean legislation does
demonstrate the value of a prescriptive approach in obtaining
compliance in particular high risk situations such as with exposure to
hazardous substances.
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General discussion
7.1 Aims and objectives of the study
The overall aim of this study was to develop a comprehensive
understanding of the management of exposure to heavy metals in
selected industries in Korea and Australia. Determining the prevalence
of heavy metal poisoning or their indicators will assist in evaluating the
effectiveness of occupational health and safety legislation in preventing
work-related illness and by implication work-related injuries.
The specific objectives of this study were to determine:
The effectiveness of heavy metal exposure management in
the fluorescent lamp manufacturing industry in Korea, and an
Oral Health Service, and lead-risk workplaces in Queensland,
Australia;
The management of the legislative arrangements for health
surveillance in Korea and Queensland, Australia;
The characteristics of the occupational health and safety
management systems that are in use in the heavy metal
industries in Korea and Australia; and
The effectiveness of prescriptive and performance based
legislative systems in protecting the health and safety of workers
in heavy metal based industries.
7
General discussion
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7.2 Limitations of the study
7.2.1 General
A consideration that arises in this type of study arises from the “survivor
bias” effect. This assumes that some people will have left the industry
with the health effect under study. It was beyond the scope of this
study to determine the extent to which people had left the industries
because of adverse effects from mercury or lead exposure.
7.2.2 Korean epidemiological data
The epidemiological data obtained from Korea did not have any data
that allowed individual subjects to be identified. This meant that it was
not possible to trace individual subjects over the 6 year period or to
ascertain if individual subjects had been tested, other than follow–up
tests, more than once a year. In addition, although this researcher
observed the collection and analysis process and found them to be in
accordance with the standards noted here, she had no control over the
quality of the collection of the samples or of their analysis.
Thus assurances had to be sought regarding the validity of results such
as those appearing as outliers. Lack of control over the sampling and
analytical processes therefore leave some room for doubt.
This survey did not cover symptoms, work practices including previous
employment, hours of work, past and current job tasks and use of the
workers’ compensation due to the lack of appropriate data to analyse.
7.2.3 Oral Health Service Study
The cases in the oral health service study were not randomly selected
but were volunteers.
The small size of the control group in the Oral Health Service Study
also prevented a number of statistical comparisons being made with
General discussion
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the experimental group. For example, although a significant difference
was found in the mean level of mercury in the urine of the control and
experimental groups, this finding is not considered representative
because of the small size of the control group.
7.2.4 Lead risk management in Queensland
The low initial response rate from lead designated doctors in this study
had a number of impacts, some of which have already been discussed.
The follow-up phone calls to the non responders revealed that the
majority of them were no longer working as lead designated doctors.
However, a small proportion was not contactable and there is no way
of confirming whether or not these persons are no longer working in the
industry.
7.2.5 Occupational health and safety management systems
The occupational health and safety management survey was
conducted in 2002 but the epidemiological data provided for the
Korean fluorescent lamp manufacturing companies ceased in 1999.
There is a likelihood that the occupational health and safety
management systems used in the Korean workplaces would have
changed over that period of time. This problem was compounded by
the inability to match the companies who responded to the
management systems survey with the epidemiological data. This was
done to preserve anonymity and encourage participation. However,
these limitations prevented any relationships between individual
company performance and the health and safety management
systems in place from being identified.
In addition, the small number of Korean fluorescent lamp
manufacturers resulted in a sample size in the occupational health and
safety management system survey and prevented any statistical
analysis of the data to explore relationships such as the impact of size
General discussion
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of workforce as was done in the Australian section of the study. This
limitation was recognised in the design stage of the study but it was
decided that such statistical comparisons may be invalid because of
differences in the two countries that it would not be possible to control.
The study therefore looked at the impact of legislation within the
countries on the industries concerned.
7.3 The effectiveness of heavy metal exposure management
7.3.1 Mercury in fluorescent lamp manufacturing companies in Korea
The study of mercury exposure in fluorescent lamp manufacturing
companies in Korea showed that mercury exposure levels as
measured in the blood and urine of workers was unacceptably high but
was improving with time while the surveillance program stayed in place.
Interestingly, the data collected as part of the occupational health and
safety management survey of some of the same firms in 2002 showed
that the number of workers needed to be removed from their job
because of excessive levels of mercury in their blood or urine had
dropped substantially from 7% of the workforce sampled in 1999 to
0.5% of the workforce of the companies surveyed in 2001/2002.
Although this latter figure is obtained from self-reported data and is not
immediately comparable because not all workplaces are included, it is
supported by the general trend of downward exposures noted in the
mercury exposure study. It should be noted that the results from the
survey could not be related to the workplaces in the study reported in
Chapter 2.
A number of disturbing trends were however also noted in the study.
Firstly, the levels of mercury measured in the urine of some workers
were well in excess of that previously reported in the literature (Jang,
Kim et al., 1989; Kim & Cha, 1990; Cha, Kim et al., 1992) with respect
General discussion
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to Korea. A previous study by Cha, Kim et al. (1992) had found that, in
one company 1.9% of workers had mercury concentrations in their
urine in excess of the diagnostic standard of 300 µg/L and 51.9% in
excess of the warning level of 100 µg/L. In this study these
percentages of cases in excess of the diagnostic standard was also
1.9% overall in the period 1994-1999. However, cases in excess of the
warning level ranged from 32% to 1% in individual companies for the
workers monitored in over the period 1994 - 1999.
It is notable that the higher levels found in this study should have
resulted in demonstrable toxic effects. Other information available in
the recorded data should provide additional information on the
symptoms experienced by the subjects but this was outside the scope
of this study. The finding is however important as it is an indicator of
possible extreme mercury poisoning of some of the subjects.
In addition, it was of concern that little action appeared to have been
taken between the first and follow-up tests to reduce the exposure of
individuals to mercury when excess levels were detected at the first
test. This finding was similar to that by Lee, Kim, et al. (1993).
7.3.2 Mercury in an Oral Health Service in Queensland, Australia
While it is acknowledged that the mercury exposure risk in dental
surgeries is not as great as that in fluorescent lamp manufacturing
companies, it is noted that a number of studies (Jokstad, 1990; Nilsson,
Gerhadsson et al., 1990; Skare, 1990; Akesson, Schutz et al., 1991;
Visser, Piper et al., 1991; Pelva, 1994; Steinberg, Grauer et al., 1995;
Echeverria, 1998; Lygre, Gronningsaeter et al., 1998; Soleo, Pesola et
al., 1998; Galic, Prpic-Mehicic et al., 1999; Schuurs, 1999; Ritchie,
Gilmour et al., 2002) have reported mercury vapour exposure from
dental amalgam production. Other studies (Lehto, Alanen et al., 1989;
Steinberg, Grauer et al., 1995; Langworth, 1997) have found mercury
in urine concentrations in dentists and other dental professionals who
General discussion
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used mercury amalgam in their work were statistically significantly
highly elevated.
In the study of workers in an Oral Health Service in Queensland the
urinary concentrations of mercury in exposed dental workers was not
found to be above generally accepted background levels. Those cases
where any mercury was recorded in the urine were followed up and no
occupational or environmental factors to explain the levels were found.
Airborne concentrations of mercury well below the workplace exposure
standard were found in some workplaces but the nature of the
monitoring and the location from which the samples were taken have
lead to the conclusion that these levels would not have contributed to
worker exposure to mercury although they are an indication of areas in
which current work practices can be improved.
A study by Ritchie, Gilmour et al. (2002) identified a number of adverse
health effects among dentists that could be associated with mercury
exposure. In this study, the symptoms reported by workers exposed to
mercury were found to be no different from those reported by the
control group and most of the symptoms reported appeared to be
related to other working conditions. It was found that mercury
exposure in the Oral Health Service was well controlled and that the
impression by some workers that it was not was more a factor related
to communication in the workplace than to current work practices.
7.3.3 Lead in lead-risk workplaces in Queensland, Australia
Two studies explored the management of lead exposure in lead-risk
workplaces in Queensland. The first reviewed the management of the
lead designated doctor system in Queensland and the second the
occupational health and safety management systems in place in lead
risk workplaces in Queensland.
General discussion
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In the past 12 months, the lead designated doctors recommended that
2% of the population monitored be removed from lead-risk jobs. This
compares with 0.5% of cases reported in the survey of fluorescent
lamp manufacturing companies in Korea that had to be removed
because of excess mercury urine results and the 1% reported in the
survey of lead-risk workplaces in Queensland.
One of the disturbing factors of the Queensland system is that it is
impossible to obtain a clear picture of the rate of exposure of workers to
lead in the workplace. Neither employers nor lead designated doctors
provide regular reports to the government. Another weakness is that
the process of having a workplace designated as a lead-risk workplace
relies on the findings of a risk assessment that the employer has the
responsibility for having undertaken. There is no specification in the
Queensland legislation for the standard to which this assessment must
be performed or any requirement for the person undertaking the risk
assessment to have any qualifications in occupational health and
safety or expertise in undertaking risk assessments.
7.4 The management of the legislative arrangements for health surveillance in Korea and Queensland, Australia
7.4.1 Fluorescent lamp manufacturing companies in Korea
Health surveillance is compulsory in fluorescent lamp manufacturing
companies in Korea. The study of the health surveillance data from
these companies shows that the degree of compliance with the
requirement to undertake health surveillance of workers appears to
have improved consistently over the period 1994-1999. However, a
weakness in the system appears to be a lack of follow-up of workers
who are found to have exposure to mercury at the time of their first
screening test in any period.
General discussion
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The study showed that 34% of workers with mercury levels in their
urine and/or blood in excess of the Baseline Standard at the first test
and underwent a later blood test still had mercury levels in their blood
in excess of the Baseline Standard. As the mercury blood levels are an
indication of recent exposure to mercury, it must be assumed that little
was done to reduce their mercury exposure in the intervening period.
This is supported by the findings of Lee, Kim, et al. (1993) that little is
done to make improvements in the workplace to alleviate the
conditions which caused the problem. In this case it would appear that
the workers have not even been removed from the exposure as
required by Korean legislation.
In 1999, 81% of cases with mercury in their blood and/or urine in
excess of the Baseline Standard underwent a later blood test in
comparison with 47% overall in the period 1994-1999. However, the
level of mercury in their blood at the time of the later test remained in
excess of the Baseline Standard in 18% of cases. This is an
improvement in the overall compliance of the legislation but still shows
that greater effort is required.
Overall, the data indicates a dramatic improvement in compliance with
the legislative requirements for the control of mercury exposure in the
period 1994-1999. It is apparent from the data that problem
workplaces have been identified and that effort has been made to
improve compliance in these. However, while there has been an
improvement in the management of mercury exposure to workers
found to have excess biological levels of mercury and the overall
exposure to mercury in the workforce has decreased, further
improvement is still necessary.
7.4.2 Health surveillance in the Oral Health Service in Queensland, Australia
On the basis of its risk assessment, the management of the Oral
Health Service had determined that no health surveillance for mercury
General discussion
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was required in their workplaces. This determination was supported by
the findings of this study.
7.4.3 Health surveillance in lead-risk workplaces in Queensland, Australia
The survey of lead-risk doctors revealed that the government received
very little feedback regarding the success or otherwise of the health
surveillance program in lead-risk workplaces and that its own database
of lead designated doctors was out of date and inadequately
maintained. Only a small percentage (27%) of lead designated doctors
had qualifications in occupational medicine or occupational health and
safety yet all were expected to advise employers on ways of controlling
exposure to lead in the workplace.
The system relies on the results of a risk assessment undertaken by
the employer who may have no expertise in this area. The employer is
not required to seek professional assistance unless the risk
assessment shows that there is a lead-risk job in the workplace. The
major professional body representing occupational health and safety
professionals in Queensland, the Safety Institute of Australia, has
expressed its concern with the lack of expertise of the persons
undertaking risk assessments on a number of occasions (Hitchings, G.,
pers. comm., 23rd July 2002).
Hitchings53 noted that while the intent of the legislation to place the
major responsibility for ensuring the health and safety of workers in the
workplace squarely with the employer was commendable, the
guidance provided to employers on undertaking risk assessments was
minimal. He concluded that it was very likely that there was an
underestimation of the risks in many industries because of the lack of
expertise of persons undertaking risk assessments and that this was
likely to be even worse in small businesses.
53 At the time of making these comments, Mr. Hitchings was President of the Queensland Division of the Safety Institute of Australia.
General discussion
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Thus, while lead designated doctors reported that the system was
working well in the workplaces that they were monitoring:
the possibility that high risk lead workplaces may not have
been identified as such in the risk assessments undertaken by
employers;
the lack of any centralised database on the extent of lead
exposure to the workforce in Queensland;
the lack of any standardised methods of health surveillance
of workers exposed to lead; and
the lack of qualifications in occupational medicine or
occupational health and safety by a large percentage of doctors
providing advice to employers on the control of lead in the
workplace,
leads to the conclusion that the legislative arrangements for the
oversight and control of lead exposure in the workplace is not working
effectively in Queensland.
A system which requires employers in particular industries, designated
high risk because of exposure to hazardous substances, to seek
professional assistance in undertaking their risk assessment would
improve the reliability of these assessments. Further, if the process of
designating doctors required them to be qualified in occupational
medicine or occupational health and safety and to report to government
on the results of their health surveillance in order to maintain their
designated doctor status this would:
Give employers access to qualified advice including the
actions necessary to reduce exposure;
Assist in maintaining the currency of the government’s
database of designated doctors; and
General discussion
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Provide government with data to assess the impact of the
health exposure program on reducing exposure to hazardous
substances in the workplace.
7.5 The characteristics of the occupational health and safety management systems that are in use in the heavy metal industries in Korea and Australia
The study of occupational health and safety management systems in
Korea showed a gradual introduction of these systems across
countries and workplaces of different sizes. Differences were noted in
the likelihood of organisations to have or be in the process of
developing fully documented health and safety management systems.
However, the implementation of a health and safety management
system was not the province of large companies alone. For
Queensland companies, while larger companies were more likely to
have commenced or completed implementing such systems, no
statistically significant difference was found in the size of the
organisation and whether or not it had a formalised occupational health
and safety management system in place.
In Queensland, for the purpose of this study the division used for the
distinction between “large” and “small” was 30 employees. This was
based on requirements of the Workplace Health and Safety Act 1995
(Qld). In Korea the distinction was 200 employees based on
observations of the data collected.
Larger organisations in Queensland were more likely to have
developed advanced elements of the occupational health and safety
management system than smaller organisations and than the Korean
organisations. For example a statistically significant difference was
found in the proportion of companies that had a written health and
safety policy, had a system in place to review their training program,
General discussion
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whether or not they used a hazard reporting system as a method of
identifying hazards, and whether or not they had a documented and
maintained emergency management system.
Because of the small sample size it was not possible to test statistically
for differences between Korean and Australian organisations. However
in most instances it was noted that the development of health and
safety management system elements lagged behind that of the
Australian organisations surveyed and the larger organisations in
particular.
However, this was not always the case. In areas where legislation
required particular activities to be carried out, the Korean companies
surveyed generally performed much better than their Australian
counterparts. For example, Korean workplaces reported 100%
compliance with both health surveillance and air monitoring
requirements in comparison with 80% (health surveillance compliance)
and 65% (air monitoring compliance) for Australian workplaces. All
Korean organisations surveyed reported having signed training records
in comparison with 38% of Australian organisations surveyed.
In other areas such as encouraging worker participation and
consultation in workplace health and safety activities Australian
workplaces were more likely to comply with the legislative requirements
– 85% of Australian companies surveyed compared with none of the
Korean companies surveyed. This perhaps arises because of the
higher involvement of workers in achieving occupational health and
safety legislative reform in Australia compared with Korea. On the
other hand the Korean organisations surveyed were much more likely
to see occupational health and safety as a line management
responsibility (100%) than the Australian companies (53%).
Overall, the picture that emerges is that larger Korean companies are
beginning to implement occupational health and safety management
systems but that the development is slower or behind that of Australian
General discussion
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companies. The initial focus in Korea is on areas where legislation
stipulates that particular actions must be taken. In contrast, the
emphasis in Australia is on broader risk management issues. In
excess of 90% of the Australian respondents indicated that they had
hazard identification and risk assessment processes in place.
Whereas organisations in the process of the development of
occupational health and safety management systems in Australia
generally also exhibit good compliance with legislative requirements
this was not up to the Korean standard in critical areas.
It is noted that Korea is a much younger industrial nation than is
Australia and that industry in Korea therefore has much less
experience in developing and maintaining hazard identification and
control measures than its Australian counterparts. In such
circumstances it was no doubt correct for Korea to introduce
prescriptive legislation to control workplace hazards in the first
instance. However, based on the results from this study, and the
progress of some companies in introducing occupational health and
safety management systems, it is possible that the time has come for
Korea to review its approach to occupational health and safety
legislation and move towards a system that is more likely to allow
flexibility in the way in which risks are managed and also address a
wider range of workplace hazards.
7.6 The effectiveness of prescriptive and performance based legislative systems in protecting the health and safety of workers in heavy metal based industries.
The data collected in this study clearly demonstrates that the
prescriptive legislative regime in Korea has lead to the development of
health and safety management systems with different emphasis to
those which have developed under the performance based legislative
arrangements in Australia. The health and safety management
General discussion
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systems developed in the Korean fluorescent lamp manufacturing
companies are more focused on meeting the regulatory requirements
of that country particularly in areas where reporting to government is
required. In Australia, the occupational health and safety management
systems are focused on a broader risk management approach. This
approach is evident even in smaller companies that do not have formal
occupational health and safety management systems in place.
While the latter approach might, on first glance, appear better because
of the probability that a wider range of risks will be identified and
therefore controlled, severe limitations in this approach were also
noted. The lack of expertise and independence of those undertaking
risk assessments in high risk areas raises the possibility that some
workers are being unknowingly exposed to hazardous substances.
This problem is compounded by the legislative arrangements in
Queensland.
These arrangements mean that the government receives little data on
the extent of exposure of workers to hazardous substances such as
lead or mercury and has no reliable data on the extent of ill health
resulting from such exposures. In addition, even where lead risk
workplaces have been identified, many of those required by legislation
to advise employers on appropriate methods of controlling exposure
have no qualifications in occupational health and safety.
In addition, while the Korean systems have limitations in that the
government has accepted responsibility for the control of exposure to a
number of hazardous substances, such as mercury, in the workplace
by dictating the procedures that employers must follow, this approach
was possibly the correct one given the relative youth of the Korean
manufacturing industry. This supposition is confirmed by the rate of
reduction in mercury exposure and indicators of mercury poisoning
noted in this study. A more serious side effect of the approach taken
General discussion
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by Korean legislators is that it has resulted in a system that focuses on
the limited areas of legislative prescription.
A number of recommendations for improvement to lead exposure
management have already been suggested. In general, the
Queensland legislative arrangements are limited in their ability to
provide government with data on the performance of companies with
respect to hazardous substances management. The system could be
improved if risk assessments in specified hazardous industries or
processes were undertaken and advice provided by persons with
formal qualifications in occupational health and safety and health
surveillance was undertaken by doctors qualified in occupational
medicine.
The influence of legislation on health and safety management systems
noted in this study suggests that this approach should result in an
improved compliance with legislative requirements in high risk areas
without diminishing the broad risk management approach taken by
much of industry. The approach would also assist small businesses
that possibly do not have the resources to develop formalised health
and safety management systems to deal with acknowledged high risk
activities.
The Korean data suggests that further improvement is still required in
the management of mercury in the workplace. This, and evidence from
the Australian experience, suggests that it is possibly too early to move
away from the highly prescriptive requirements for the management of
hazardous substances in the workplace in Korea. However, the move
by some larger companies to implement broader health and safety
management systems suggests that amendments to the legislation
which encourage this advance should be made. As shown in the
discussion relating to Queensland companies above, there is no
reason why these approaches cannot exist side by side.
General discussion
-324-
-325-
Conclusion
This study has shown that the legislative controls in place in Korea and
Australia for the protection of workers against exposure to heavy
metals have both been relatively successful in improving conditions in
the workplace and providing some protection to workers. However
both the prescriptive approach adopted by the Korean Legislators and
the performance-based approach adopted in Australia and exemplified
by the example of Queensland used in this study have weaknesses.
In the Korean instance the response of companies to the prescriptive
approach is largely a reactive one. The Korean companies surveyed
have systems in place to ensure that they meet the requirements for
health surveillance and environmental monitoring required by
legislation. However, they appear to rely on the results of biological
monitoring to alert them to problems rather than adopt more wide
ranging risk management techniques to identify and assess risks
wherever they may arise in the workplace and then manage these risks
appropriately. They also appear to react slowly to cases of
overexposure and do little to reduce exposure to individuals.
On the other hand the performance-based approach adopted in
Queensland has resulted in workplaces that are less focused on
individual legislative requirements but more likely to introduce systems
to manage a wide range of work-related risks. This is particularly the
case where workplaces are of a size where the development of formal
occupational health and safety management systems is practical. The
weakness of the system lies in the emphasis it places on the risk
assessments undertaken by unqualified persons to establish the
8
Conclusion
-326-
degree of risk to which workers are exposed. The problem is
exacerbated by the lack of information collected by government on the
performance of its legislative arrangements to limit exposure to
hazardous substances.
As Korean workplaces have now had some experiences of working
within a prescriptive system where the government has accepted
responsibility for the way exposure to hazardous substances is
controlled in the workplace, it is likely that organisations are now
sufficiently educated to move towards a system that requires them to
take more responsibility for the control of this and other work-related
risks. There are signs of this occurring independently of government
legislation as there is early evidence of companies starting to develop
and implement occupational health and safety management systems.
In the Australian context there is a need for governments to revisit the
need for workplaces to report on their performance where exposure to
particular hazardous substances is concerned. There is also a need to
ensure that risk assessments are undertaken with the input of expert
advice in instances where exposure to these hazardous substances is
involved. The problem of how to resource small businesses that may
not have the resources to develop sophisticated occupational health
and safety management systems also needs addressing.
The study has demonstrated that strict adherence to either a
performance-based or a standards-based occupational health and
safety legislative approach has weaknesses. The recommendations
that have arisen as a result of this study suggest that elements of both
systems are necessary in order to achieve a healthy and safe working
environment.
Further research is needed to confirm the wider impact of occupational
health and safety management systems in adequately identifying and
managing a range of work-related risks. Similarly, the broader
workplace health and safety performance of Korean organisations
Conclusion
-327-
needs to be assessed before the recommendations regarding a
possible change in the emphasis of Korean occupational health and
safety legislation are implemented.
Building on the results of this study, further research is also necessary
to identify the influence of social, political and economic factors on
workplace health and safety management and the mixture of
performance-based and standards-based legislative arrangements that
will achieve the best outcomes in a range of different circumstances.
Conclusion
-328-
-329-
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