The ABCs of Medical Surveillance

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The ABCs of Medical Surveillance

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The Role of Surveillance in Occupational Health Systematic monitoring of health events and exposures in

working populations to prevent and control occupational hazards and their associated diseases and injuries

Essential Functions To gather information on cases of occupational diseases/injuries

and on workplace exposures To distill and analyze data To intervene on the basis of data to alter the factors that

produced health events and hazards To disseminate organized data to necessary parties: workers,

unions, employers, government agencies, the public

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Role of Medical Surveillance in Occupational Health Public Health Surveillance:

Population-based Undertaken by government agencies

Medical Surveillance: Ongoing application of medical tests and procedures to individual

workers who may be at risk for occupational morbidity to determine whether a disorder may be present

Can detect patterns of occupational illness in program participants Medical screening: If an individual/population is exposed to a

toxin with known effects and the tests and procedures are highly targeted to detect the likely presence of one or more effects in these persons

Hazard Surveillance: monitoring of exposure to chemical agents, physical hazards or radiation in the workplace

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The Occupational and Environmental History and Physical Examination Examinations:

Preplacement Periodic medical surveillance/medical screening Return to work assessments Exit examinations Evaluation for specific occupational exposures

Occupational History: List all jobs held and approximate dates of employment Significant changes in job duties; second jobs “Have you ever worked with or been exposed to any of the

following…?” Environmental history: home environs, water source, heating

source, indoor combustion sources, pets, hobbies, work of family members

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Preplacement Examinations Evolved from a “preemployment:” or exclusionary exam to

Preplacement/Postoffer Targeted examination, job focus, business necessity Americans with Disability Act 1990

“Otherwise qualified” individuals with disabilities cannot be excluded from employment if they can perform the essential functions of the job, with or without reasonable accommodations.

“Physical disability”: an impairment that substantially limits a major life activity “Disability” is defined after mitigating factors are addressed, i.e. medications,

prosthetics “Essential Job Functions”:

Fundamental – not performed as needed , or occasional; employer decision Job description – physical tasks as determined by a job analysis specialist If leaving out a certain function changes the job in a significant manner, than it

is an essential function. “Reasonable accommodations:

If a candidate is unable to perform the essential functions of the job Employers responsibility to determine undue hardship

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Preplacement Examinations Fitness for duty evaluation:

Determines whether a previously hired employee who was able to perform the essential functions of the job is still able to safety perform these essential functions.

Evaluation post clearance from PCP for non-occup issue

Examining physician should have access to the employees pertinent medical and personnel records in order to conduct evaluation If employee will not sign for release of records, may proceed with examination

If disabled or unfit for duty, document the restrictions/limitations

Employer decides if accommodation exists

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The Medical Surveillance Examination >30% of the US workforce receives periodic occupational

health examinations Screening: 2o prevention which focuses on the individual

for the early diagnosis and treatment Surveillance: 1o prevention focusing on identification and

elimination of the causes of disease; aggregates info from individuals to examine patterns within a population.

In accordance with OSHA standard Many employers conduct programs for hazards without

standards. The potential toxicity of ~80% of the chemicals used in the

workplace has not been evaluated in humans or in vivo or in vitro test systems.

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OSHA Medical Surveillance Requirements Acrylonitrile 29 CFR 1910.1045 Arsenic (inorganic) 29 CFR 1918 Asbestos 29 CFR 1910.1001 Benzene 29 CFR 1910.10288 Beryllium Federal Register 64:253:68853-68914 Bloodborne Pathogens 29 CFR 1910.1030 1,3 Butadiene 29 CFR 1910.1051 Cadmium 29 CFR 1910.1027 Cotton Dust 29 CFR 1910.1027 Diesel Exhaust 30 CFR 72 EEOC/ADA Ethylene oxide 29 CFR 1910.1047 Formaldehyde 29 CFR 1910.1048 Lead 29 CFR 1910.1025 Methylene Chloride 29 CFR 1910.1052 Noise 29 CFR 1910.95 Record Keeping 29 CFR 1904 Respirator Protection 29 CFR 1910.134 Vinyl Chloride 29 CFR 1910.1017

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Other Chemicals and Substances Acetic Acid Acrolein Asphalt/Asphalt Fume Carbon Disulfide Carbon Monoxide Ceramic Fibers Chlorine Cholinesterase-Inhibiting Substances

(Pesticides) Cyanides Cytotoxic Drugs Fluoride Gasoline Glutaraldehyde Hydrogen Fluoride Hydrogen Chloride Hydrogen Peroxide Isocyanates Malathion Manganese/Manganese Fumes

Mercury (inorganic) Metal working fluids Nickel Nitrogen dioxide Ozone Peracetic acid Phenol and phenolic compounds Proteolytic enzymes Psyllium Silica (Crystalline) Silver Sodium Hydroxide Soldering Solvents Sulfur dioxide Toluene/Xylene Triethylamine Trimellitic anhydride Zinc Oxide Fumes (Metal Fume Fever)

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Respirator Protection Standard Components of the program

All employees required to wear respirators must take part in the company’s training program prior to use, annually and with changes in workplace or type or respirator

Program administrator: Oversees hazard assessment, respirator selection, respirator care

and maintenance, medical evaluation, fit testing, employee training, respirator use, program assessment, record keeping

Nine components: Respirator selection, medical evaluation, fit testing, emergency

activities, maintenance procedures and schedules, adequacy of air quality, quantity/flow for respirators, training regarding respiratory hazards, and limitation of respirator fit/use/maintenance, evaluation of effectiveness of the program

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Respirator Protection Standard Prior to respiratory selection, employer reviews worker exposures,

job demands and potential adverse effects of interactions; focus on engineering and administrative controls

Qualitative vs quantitative testing: Qualitative: negative pressure air-purifying respirators (fit factor of 100 or

less) and all positive pressure respirators Quantitative: used for all respirators Isoamyl acetate (banana oil), saccharin or Bitrex solution, irritant smoke

( not recommended by NIOSH)

Procedures for IDLH (Immediately Dangerous to Life and Health) environment: standby personnel must be equipped with respirators and rescue equipment consider all oxygen deficient atmospheres as IDLH SCBA required for interior structural firefighting

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Respirator Protection Standard: Medical Evaluation

Recommend inclusion of questionnaire, single view chest x-ray and PFT.

Periodic examinations: usually annual questionnaire +/- PFT CXR: every 5 years or as medically indicated For workers with lesser exposures: OSHA questionnaire only and

examinations every 2 years The employer must ensure that a follow-up medical examination

is provided for an employee who gives a positive response to any question contained in Part A, Section 2, questions 1-8 Tobacco, seizures, diabetes, allergic reactions, claustrophobia,

trouble smelling odors, lung disease, CAD, Medications, Problems with respirator use. (eye irritation, skin allergies/rashes, anxiety, weakness/fatigue)

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The American National Standards Institute (ANSI), The National Institute for Occupational Safety and Health (NIOSH) and ACOEM suggest medical evaluations at time-based intervals based on worker age and the type of respirator used.

The American Thoracic Society (ATS) recommends that workers with respiratory symptoms, workers > 45 years wearing SCBA and workers > 55 years old have PFTs.

Exercise stress testing (EST): > 10 METS without EKG changes unlikely to have clinically

significant CAD American College of Sports Medicine: Prior to vigorous exercise,

EST for healthy men >40, healthy women >50, persons with 2 or more cardiac risk factors, or persons with known disease

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American Academy of Family Practice recommend exercise ECGs for jobs linked to police safety and require high cardiovascular performance.

DOT, NRC, FAA recommend screening certain classes of

workers for asymptomatic heart disease.

ANSI recommends those who use SCBA or a re-breather respiratory in strenuous work conditions for EST

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Age-based Recommended Medical Evaluation Frequency

AGE Light to Moderate Work

Strenuous work with SCBA

<35 Every 5 years Every 3 years

35-45 Every 2 years Every 18 months

>45 Every year Every year

McClellan, Schusler: Guide to the Medical Evaluation for Respirator Use. Table 3-4, p 59, 2000.

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Spirometry Interpretation –Obstructive Lung Disease Is FEV1/FVC%pred> LLN (lower limit of normal)?

YESnot obstructed; IF NO

Is FEV1%pred> LLN? YESborderline obstruction; IF NO

Is FEV1 (60%pred - <LLN)? YESMild obstruction; IF NO

Is FEV1%(41-59%pred)? YESModerate obstruction; IF NO

Is FEV1< 40%pred? YES Severe obstruction

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Spirometry Interpretation – Restrictive Lung Disease

If FEV1/FVC%pred WNL, with FVC < LLN mixed obstructive/restrictive pattern

Is FVC%pred> LLN? YES Not restricted; IF NO

Is FVC (60%pred- <LLN)? YESMild restriction; IF NO

Is FVC (51-59% pred)? YESModerate restriction: IF NO

Is FVC < 50% pred? YES Severe restriction

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Lower Limit of Normal for Spirometric Percent Predicted Values from Knudson Prediction Equation

AGE FVC FEV1 FEV1/FVC% FEF25-75

25-39 76.9% 70.3% 85.9% 55.3%

40-69 75.2% 77.9% 85.9% 59.2%

FEMALE

AGE FVC FEV1 FEV1/FVC% FEF25-75

25-39 81.1% 79.1% 86.9% 55.3%

40-69 73.4% 77.2% 86.9% 40.3%

MALE

McClellan, Schusler: Guide to the Medical Evaluation for Respirator Use. Table 3-6, p 63, 2000.

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Respirator Protection Standard:Medical Decision Making Seizures:

PCPs written opinion May be approved for respirator use if seizure free for 6-12 months

without impairment or symptoms, no med side effects May approve: History of early childhood seizure due to fever, isolated

seizure > 5years ago or multiple seizures > 10years ago without recurrence off medication

Controlled seizure activity (no seizure on/of med in the last year) PCP opinion, non IDLH environment, exam for SCBA, med eval for IDLH

Poorly controlled (changing meds, Workplace exposure to triggers, side effects from meds Medical eval, neurologist letter, accommodations or denial

DOT, NFPA 1582: epileptic conditions are disqualifying unless identifiable precipitant, normal EEG, normal neuro exam, seizure free 1 year off meds, neurologist’s statement

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Respirator Protection Standard:Medical Decision Making

Diabetes Episodic, unpredictable impairment of psychomotor abilities due

to hypoglycemia presents the greatest endocrinologic concern for respirator use

Majority of people with Type 1experience between 1-2 hypoglycemic episodes

Minimum of 17% of people receiving conventional insulin treatment have a least one severe hypoglycemia episode per year

Issues: shift work, irregular meals, erratic exercise and difficulty maintaining a regular medication schedule

Driving simulators: driving performance deteriorates significantly when blood glucose drops below 65mg/ml Impairs judgment about physical capabilities At least 50% of drivers with low BS decide to drive at least 50% of the

time

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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide Acrylonitrile

Manufacture of acrylic fibers, rubber-like materials, pesticides OSHA PEL 2ppm, 10ppm ceiling (15minutes) Health Effects

Route of exposure: inhalation and skin Potent mucous membrane irritant; skin blistering Metabolized to cyanide: cyanide/thiocyanate in

blood/urineweakness,asphyxia, death Suspected human colon/lung carcinogen

Medical Surveillance: at least annually skin, respiratory tract, GI, neurolook for nausea vomiting, dizziness,

weakness, CNS signs that may indicate exposure CXR, Occult blood for workers>40yrs Respirator program

Biological monitoring: thiocyanate levels Mean postshift urine levels of 11.4mg/l8 hr avg exposure of 4.2ppm Chronic human toxicity: 16-100ppm for 20-45 min nasal irritation, H/A ,

nausea, fatigue

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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide

1,3 Butadiene Exposure occurs primarily through inhalation during monomer/polymer production OSHA PEL 1ppm (TWA), 15 minute STEL of 5ppm, action level 0.5ppm Health Effects:

Liquidskin burns, frost bite; Gas mucous membrane irritant, blurred vision, cough, drowsiness

Anesthetic at high concentrations Human/animal carcinogens: leukemia and lymphosarcoma; male/female

reproductive toxicity and embryo toxicity in animals; infertility, miscarriage, anemia

Medical Surveillance: > PEL on 10 or > days/yr > PEL on > 30days/yr for 10 or more years > the action level on 60 or more days/yr for 10 or more years Above 10ppm on 30 or more days in any past year Any employee exposed in an emergency situation

Medical screening no later than 48 hours after the exposure CBC within 48 hours of the exposure, repeated monthly for 3 months

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1,3 Butadiene (cont)

Medical Surveillance: Health questionnaire yearly, emphasis on blood disorders Exam focused on lymphatic system, liver, spleen, skin Respirator standard CBC with diff and platelet count

Before employees assuming duties in a job with BD exposure, Every 3 years after the initial physical exam or at the discretion of

health professionals At time of reassignment to an area where exposure is below the

action level At termination of employment if 12 months have elapsed since last

physical examination

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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide

Vinyl Chloride Primary use is production of Polyvinyl Chloride OSHA PEL 1ppm (8 hr TWA); STEL 5ppm (15 minutes) Health Effects:

Historically – narcosis, acroosteolysis (resorption of the terminal phalanges) 1970s epidemiological studies showed link to hepatocellular injury and

angiosarcoma of the liver Pneumoconiosis: high dust exposure >10mg/m3

Medical Surveillance: History: alcohol use, hepatitis, exposure to hepatotoxic drugs/materials, blood

transfusions Exam: liver, spleen, kidneys, skin, connective tissues and respiratory Examine annually; if working with VC/PVC manufacturing for 10 years or

longer, must be examined every 6 months Lab findings:

Elevated liver enzymes/alkaline phosphatase, Fasting levels of serum bile acids/urinary coproporphyrins – indicators of

early chemical industry Alpha glutamyl transpeptidase level ~vinyl chloride exposure, greater

specificity Liver US – periportal fibrosis among highly exposed workers. Biomarkers: p63 and DNA adducts under investigation

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Plastics, Rubbers and Resins:Acrylonitrile, 1,3 Butadiene, Vinyl Chloride, Carbon Disulfide Carbon Disulfide (not federally mandated)

Intermediate for other chemical (I.e. carbon tetrachloride) and products (cellophane, rayon viscose fibers, adhesives, herbicides); manufacture of optical glass

OSHA PEL 20ppm (8 hr TWA); STEL 30ppm; 30minutes maximum allowable exposure 100ppm; IDLH (immediately dangerous to life and health) 500ppm

Health effects: Foul odor desensitizes olfactory system Skin and Inhalation: skin irritation, mucous membranes (esp eyes), CN deficits, peripheral

neuropathy, paresthesias, unsteady gait and dysphagia; Nerve damage does not resolve with end of exposure

Extreme intoxication – parkinsonism-like syndrome, psychosis and suicide May accelerate the development or worsen heart disease – risk decreased with removal Eyes: microaneuryms Ears: high frequency hearing loss/ vestibular symptoms of vertigo and nystagmus Effects libido; women at <10ppm menstrual abnormalities, spontaneous AB, premature

births No carcinogenicity

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Carbon Disulfide (continued)

Medical Surveillance: History/exam: eyes, skin, central and peripheral nervous systems,

CAD, liver, kidneys History and physical exam every 3-5 years

Biological monitoring: Preshift urines for 2-thiothiazolidine-4-carboxylic acid (TTCA) Spot urine of 0.95 mmol per mole of Cr proposed as a reliable

indicator of recent exposure 5mg corresponds to an 8 hr TWA

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Healthcare: Formaldehyde and Ethylene Oxide Formaldehyde

Backbone of chemical industry Tissue preservative and disinfectant; construction and insulation

materials, cosmetics, fertilizer, textiles, foundries, pesticides/fumicides, ink, photography and others

OSHA PEL 0.75ppm 8-hr TWA; STEL 2ppm (15min); Action level 0.5ppm; IDLH (Immediately dangerous to life and health) 100ppm

Health Effects: 1ppm – potent irritant of eyes, skin, mucous membranes and

respiratory tract Dermatitis, sensitization Lungs: rapid absorption and excreted as formic acid; bronchitis,

allergic/asthmatic reactions, pulmonary edema Sensitization: occupational asthma associated with formaldehyde

resin dust Probable human carcinogen – lung, nasopharyngeal, malignant

melanoma, pancreatic cancer in embalmers Neuropsychologic issues; spontaneous abortion (cosmetologists/lab

workers with use of disinfectants and formalin); delayed conception in woodworkers

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Formaldehyde (continued)

Medical surveillance Focus on respiratory, skin, eyes and mucous membranes and to

allergens/allergic reactions General medical questionnaire; exam focused on eyes, skin,

mucous membranes and upper respiratory tract Baseline PFT and annually Respirator Standard

Biological Monitoring Urinary formate: useful with ambient concentration of >1ppm Low level exposure during embalming associated with

cytogenetic changes in epithelial cells of the mouth and in blood lymphocytes; may be useful biologic monitoring

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Healthcare: Formaldehyde and Ethylene Oxide

Ethylene Oxide (ETO) Manufacture of ethylene glycol (antifreeze, polyester, film, bottle),

detergents, textile chemicals, pesticide, hospital sterilant, medical products Mostly used in closed operations (<1ppm) Potential exposure: maintenance, repair, product sampling,

loading/unloading transport tanks ~0.02% of production used for sterilization in hospitals; NIOSH

estimates that 75,000 health care workers have potential exposure to ETO.

Field surveys of hospital gas sterilizers have generally found 8 hr TWA exposures <1ppm; opening sterilizer, transfer of sterilized instruments to central supply, tank changes

OSHA PEL 1ppm TWA, 5ppm excursion limit (15min)

NIOSH: REL <0.1ppm TWA; 5ppm ceiling (10min/d)

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Ethylene Oxide (continued)

Health Effects: Ether-like odor, but odor threshold 700ppm Absorbed through skin, respiratory tract Binds to DNA; may cause cellular mutation Irritating to eyes, respiratory tract, skin, respiratory depression at

high concentrations URI irritation between 200-400ppm >1000ppm may cause H/A, nausea, dypsnea, vomiting, drowsiness,

weakness, incoordination Splashes can cause burns

Reproductive toxicity men and women: increase spontaneous AB and preterm birth

Human carcinogen-lymphatic/ hematopoietic, stomach Neuropsychiatric, neuropathy Occupational asthma

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Ethylene Oxide (continued)

Medical Surveillance Exposed at or above action level for at least 30 days during the

past year; upon termination of employment, reassigned to a work area with ETO exposure below the action level; emergency exposure of signs and symptoms

Pulmonary, hematologic, neurologic, reproductive systems Initial white blood cell count and periodically if exposure >0.5ppm

8-hr TWA or of intermittent exposures exceed 5ppm Consistent changes in CBC have not been demonstrated Can see elevated numbers of eosinophils, RBC, HCT

Biological monitoring Increased chomosomal aberrations

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Solvents/Paints Benzene

Core of aromatic hydrocarbons; Aromatics include benzene, toluene (methyl benzene), xylene

(dimethyl benzene), ethyl benzene, cumene (isopropyl benzene) styrene ( vinyl benzene)

Half of benzene used to synthesize ethyl benzene for production of styrene.

Toluene/Xylene principally used in paints adhesives and pesticides.

OSHA PEL 1ppm 8-hr TWASTEL 5ppm over 15 minute period

Action level 0.5ppm

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Benzene (continued)

Health Effects Acute anesthetic, respiratory tract irritation, dermatitis,

neurobehavioral dysfunction Benzene: bone marrow, aplastic anemialeukemia (acute neuro

behavior No evidence that substituted benzenes have any of the myelotoxic

effects. Toluene: renal tubular acidosis, cerebellar ataxia Toluene/xylene: raise auditory thresholds in animal at low level Benzene: human carcinogenicity

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Benzene

Medical Surveillance: All employees who are or may be exposed to benzene at or

above the action level for 30 days or more per year and employees engaged in certain manufacturing must have surveillance

Past exposure to benzene and other heme toxins, blood dyscrasias (hematologic neoplasms, genetic heme abnormalities), renal or liver dysfunction, medicines, previous exposure to ionizing radiation and marrow toxins.

Annual physical examination for signs related to blood disorders; CBC, WBC with differential, quantitative thrombocyte count, indices

(MCV, MCH, MCHC) Emergency exposure: provide end of shift urinary phenol within

72 hours; urine specific gravity is to be corrected to 1.024. If urinary phenol = to or > than 75mg/l, CBC, RBC count, WBC with

diff and thrombocyte count monthly for 3 months.

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Solvents/Paints Methylene chloride:

Paint remover, manufacture of urethrane film OSHA 8-hr TWA PEL of 25 ppm and STEL of 125 ppm Health effects – Inhalation hazard

CNS depression: coordination/alertness Cardiac toxicity: Metabolized to CO – susceptible individuals include

persons with heart disease and those with risk factors for hear disease

Liver toxicity Medical surveillance

At or above the action level (1/2 PEL) on 30 or more days per year or above the 8-hr TWA PEL or the STEL 10 or more days per week.

Neuro, skin, hematologic, liver disease, heart disease, risk factors for cardiac disease.

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Methylene Chloride (continued) Medical surveillance (continued)

Annual updates of the medical/work histories for each affected employee Physical examinations, including lab surveillance

45 yrs or older within 12 months of initial surveillance or any subsequent surveillance

<45 years within 36 months of initial surveillance or subsequent surveillance

If employee leaves the employers workplace to is reassigned to an area where exposure to MC is consistently at or below the action level and STEL, medical surveillance must be made available at that time if 6 months or more have elapsed since the last medical surveillance.

Must provide opinion concerning whether exposure to MC may contribute to or aggravate the employees existing cardiac, hepatic, neurology, dermal disease and whether employee has any other medical condition that would place him at increased risk of material impairment from exposure to MC

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Metals – Arsenic, Beryllium, Cadmium, Lead, Mercury (inorganic)

Arsenic Elemental, trivalent, pentavalent – most common inorganic forms Most reports of acute/chronic toxicity – arsenic trioxide

Pentavalent trivalent Arsine gas- extremely potent/acute poison; used in microelectronics and in

the manufacture of gallium arsenide substrates Arsenic trioxide/pentoxide used in pesticides Metallic arsenic – alloy for hardening lead in battery grids, bearing, and

cable sheaths Exposure: maintenance, manufacture, flu dust (smelting) Environment: average daily intake: 10-50ug/d; drinking water standard

10ppb, organic arsenic compounds present in seafood – not metabolized, excreted unchanged

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Arsenic (continued) Ingestion and inhalation; limited skin absorption Taken up by RBCliver, kidney, muscle, bone, skin, hair As: OSHA PEL and ACGIH TLV 0.01mg/m3 TWA Arsine: OSHA PEL and ACGIH TLV 0.05ppm Health Effects:

Irritation to skin, eyes, mucous membranes GI (fluid loss, bleeding) Nervous system: Neuropathies, weakness, paralysis Cardiomyopathy, peripheral vascular disease Lung Cancer, leukemia, lymphoma, angiosarcoma of the liver

Medical Surveillance: Absorbed trivalent arsenic is metabolized to dimethlarsinic acid

(DMA) and monomethylarsonic (MMA) and excreted in the urine with a half-life of 10 hrs

Organic arsenic cpds excreted unchanged in the urine

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Arsenic (continued) Medical Surveillance

Preplacement surveillance For workers exposed to inorganic arsenic for at least 30 days per year Focus on history of smoking history and evidence of respiratory disease CXR – PA view Nasal and skin exams Respiratory standard: exposed above action level (5ug/m3)

Periodic surveillance For covered employees <45 years old with < 10 years employment in areas

exceeding the action level; annual interim history For other covered employees, interim history, physical exam and lab studies

every 6 months Lab studies:

Measure DMA, MMA eliminate confusion over dietary sources or organic arsenic compounds

Nonexposed workers<10ug/g Cr Workers exposed to 0.01mg/m will have level of 50ug/g Cr

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Beryllium Production of hard, corrosion-resistant alloys for use in the

aerospace industry; nuclear reactors, ceramics, semiconductors Mining of beryllium ore is not associated with adverse health

effects; use of beryllium compounds, especiallly beryllium oxide carries substantial risk of disease

Exposure to minute ultrafine particles, rather than total mass/dose is key factor in sensitization

OSHA PEL 2.0ug/m3;NIOSH REL not to exceed 0.5ug/m3; ACGIH TLV 0.2ug/m3

Poorly absorbed after inhalation, ingestion or skin Retained in lung, deposited in bone, liver and

spleenNoncaseating granulomas Slow renal excretion; confirms exposure, levels usually

undetectable in nonexposed individuals.

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Beryllium (continued) Health effects:

Acute exposure: irritant effects on eyes, mucous membranes, respiratory tract; tracheobronchitis, chemical pneumonitis, pulmonary edema; after skin contact irritant/allergic dermatitis, granuloma

Chronic exposure: exertional dypsnea, fatigue, wt loss, rales, lymphadenopathy, clubbing, pulmonary HTN

Lung cancer in humans; lung cancer, osteogenic sarcoma in animals Medical Surveillance

Preplacement: Medical/occupational histories: previous or anticipated exposure Respiratory standard as appropriate Physical exam: skin, eyes, respiratory tract CXR – B reader, PFT Be-induced lymphocyte proliferation (Be-LPT): confirms sensitization

Periodic: Annually for beryllium workers, every 3 years for beryllium associated workers Hx, PE, Respiratory Questionnaire Be-LPT CXR every 5 years

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Cadmium Metal plating, solder, smelting (cadmium oxide), battery alloys, pigments,

printing, semiconductors Present in the diet (liver, shellfish, meat by-products, vegetables),

environmental exposure – exposure to cigarette smoke @ 2ug/day Absorbed primarily through ingestion; inhalation 10-40%; GI 5% Renal excretion with t1/2 of 8-30yrs cadmium nephrotoxicity OSHA PEL – 5ug/m3 at 8 hr TWA; Action level – 2.5ug/m3

Health effects: Acute inhalation: sore throat, H/A/, myalgia, nausia, fever, metallic taste

SOB, chemical pneumonitis, respiratory failure; hepatic/renal injuty Chronic exposure: proteinuria with excretion of LMW proteins (B1, B2

microglobulins) renal stones, bone pain, pulmonary fibrosis, emphysema, central/peripheral nervous system, human carcinogen (lung, GU,Prostate), reproductive effects (testicular)

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Cadmium (continued) Medical Surveillance

Preplacement:: Medical/Occupational hx: cardiovascular, respiratory,

renal,reproductive, musculoskeletal, hematopoietic Physical exam: including prostate exam for male >40 CXR/PFT – pulmonary toxicity/respirator use Kidney, liver, Hb Annual exam for employees with exposure > 30 days

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Cadmium (continued)

Actions Biological Monitoring Result

Annual biological monitoring

Medical exam every 2 year

Urine Cad < 3ug/g Cr

B2-Microglobulin < 300ug/g Cr

Cadmium in blood < 5 ug/L whole blood

Semiannual biological monitoring

Medical exam annually

Exposure assessment

Exposure control

Urine Cad 3-7 ug/g Cr

B2 Microglobulin 300-750 ug/g Cr

Cadmium in blood 5-10 ug/L whole blood

Mandatory removal

Biological monitoring every 3 months

Medical examination every 6 months

Exposure assessment

Urine cadmium >7ug/g Cr

B2-Microglobulin >750ug/g Cr

Cadmium in blood >10ug/L whole blood

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Metals – Arsenic, Beryllium, Cadmium, Lead, Mercury (inorganic) Productions of electrical equipment, instruments, medicinal/skin

care products, lubrication oils Exposure via inhalation of mercury vapor, ingestion, skin contact

with liquids or salts ACGIH TLV 0.025mg/m3

Health effects: CNS, blood, kidneys, liver, respiratory Mercury vapors: Micromercurialism – weakness, fatigue, weight loss,

mercurial “facies” (tremors), “Mad as a hatter”. Medical Surveillance

Focus medical/occupational hx: CNS, respiratory, kidneys, skin Urine Hg history of exposure Workplace monitoring – urine is first choice Normal concentrations: nonexposed <0.01mg/L whole blood; <10ug/g Cr

urine; substantial seafood consumption – high blood levels with low urine levels

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Mercury (inorganic)Medical Surveillance

Air Exposure Urine HG Level Action

>50ug/m3 >100ug/g creatinine Remove from exposure until <50

Medical exam if over 150 or if (2) consecutive levels exceed 100

Repeat measurement weekly

50ug/m3 75-100ug/g Cr Monitor weekly

Perform hygiene assessment to limit exposure

25-50ug/m3 50-75 ug/g Cr Monitor monthly 25 mg/m3 35-50ug/gCr Monitor quarterly

<25ug/m3 <35ug/g Cr Monitor semiannually

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Lead: Storage batteries, alloys, pipes, cable sheathing solder, paints/plastics,

cosmetics, munitions, glassware, jewelry Occupational exposure is a result of a combination of inhalation and ingestion Environmental exposure: auto exhaust, near lead smelters, moonshine, acidic

foods/beverages in ceramics, herbal remedies Approximately 40% of inhaled lead oxide fume absorbed through the respiratory

tract; GI absorption 5% Greater GI absorption in infants/children Iron, Ca deficiencies and high fat diets increase GI absorption

Metabolism: Bound to RBC’s free fraction in plasma distributed to brain, kidney, liver, skin,

muscle Crosses the placenta (fetal level ~maternal levels), pregnancy mobilizes lead Bone is major site of deposition of absorbed lead Binds to sulfhydryl groups (found in hair and nails) Excreted primarily via kidney; t1/2 5-10 years

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Lead Water soluble alkyl lead compounds are readily absorbed

through skin contact, inhalation or ingestion Tetraethyl/methyl lead tri alkyl metabolites toxicity Accumulates in CNS – fat soluble Ultimately converted to inorganic lead and excreted in urine

Health Effects Acute: GI (abdominal pain, constipation, N/V tarry stools);

Neurologic manifestations of lead encephalopathy (H/A, confusion, stupor, coma, seizures); Renal failure/oliguria

Chronic: Early: Fatigue, irritability, vague GI symptoms, arthralgia/ myalgias Later: confusion, memory, distal motor neuropathy (wrist/.foot drop);

encephalopathy/seizures/coma; infertility (spermatogenesis, spontaneous AB); HTN, cardiac conduction, gouty arthritis, nephropathy

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Lead Medical Surveillance

Focus on lead exposure history, hygiene, GI, heme, renal, repro, neuro, pulmonary status (respiratory use), BP

Labs: BLL (blood lead level), ZPP, HB/HCT, Cr/UA

BLL – recent exposure (days/weeks); nonexposed: 1-5ug/dl; subtle effect on central/peripheral nervous system 30-50ug/dl

ZPP – alters heme synthesis increase ZPP Recent studies: at BLL of 17ug/dl see increase ZPP Abnormal for @120 days Represents average lead exposure for past 3 months Limited usefulness since health effects occur at much lower

levels (CDC recommends <10ug/dl for children) Chronic exposure:

K-band xray fluorescence of bone is best EDTA lead mobilization test (>350ug/L) confirms past exposure,

but not lead toxicity

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Lead Medical surveillance (continued)

Medical examinations: Yearly for BLL > 40ug/dl Prior to assignment Signs/symptoms of toxicity

Medical surveillance: Required for exposure to air level > 30ug/m3 for at least one day in 12

months BLL every 6 months if <40ug/dl BLL every 2 months if > 40ug/dl until (2) consecutive determinations

are < 40 ug/dl Monthly during medical removal

For >60ug/dl Average levels >50ug/dl Risk of health impairment May return if (2) consecutive BLL <40ug/dl

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Welding Application of heat/pressure to join metal Primarily manual arc welding used, but automation increasing Health hazards: metal fumes, particulates, gases, radiation

(infrared, UV), noise, electricity, ergonomic stress Main exposure is to iron oxidebenign pneumoconioisis Exposure to manganese, fluoride films Chromium/Nickel/manganese present in stainless steel alloys Stainless steel surface reflects UV radiation nitrogen oxide,

ozone Low hydrogen welding of stainless steel generates high

concentration of fluoride fumes, aluminum oxide formation Cadmium containing silver solder generates cadmium

oxideacute lung injury, death Soldering: low temp, generally not associated with significant

metal fumes; exposure to lead dust; Rosin- skin sensitizers, allergic dermatitis

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Welding (continued) Acute Exposure:

Photokeratitis: UVB radiation exposure for several seconds- pain, burning, grit-like feeling; conjunctival injection; punctate depressions over cornea; self-limited, resolving in several hours

Metal fume fever: i.e. Zn – benign, self limited with delayed onset of 8-12 hours; fever, chills, cough, myalgias, metallic taste

Pulmonary Upper respiratory irritation: dusts, ozone, aluminum oxide, nitrogen oxides,

cadmium oxide Asthma: chromium, nickel Acute lung injury and pulmonary edema: nitrogen oxide, cadmium oxide

Musculoskeletal trauma Chronic exposure:

Siderosis – accumulation of nonfibrogenic iron oxide particles in the lung Small increases in lung cancer – chromium and nickel in welding of

stainless steel

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Mineral Fibers: Asbestos and Man-Made Mineral Fibers (MMMF)

Asbestos Thermal and electrical insulation for fireproofing, in cement products such as pipes

and panels Significant exposure due to demolition of asbestos containing buildings Generally believed that all forms (serpentine and amphiboles) of asbestos have

these effects: Serpentine (chrysotile)

90% of asbestos found in the US On per fiber basis, highest risk of lung cancer – very long thin fibers

Amphiboles ( amosite, crocidolite, anthophyllite, tremolite) Most common are chrysotile, amosite, crocidolite

Health effects Inhalation of fibers: asbestosis, pleural inflammation, mesothelioma and other

lung cancers No acute symptoms; chronic effect can take up to 40 years to manifest Non-smoker: 5X increased risk of lung Cancer; Smoker: up to 100x risk

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Asbestos (continued) OSHA standard: 0.1 fiber/cm3 of air as an 8hr TWA for fibers longer

that 5 um and having a length to diameter ratio of at least 3:1 or excursion limit of 1 fiber/cm3 for 30 minutes

Medical Surveillance For all workers exposed to asbestos fibers at or above the TWA

or excursion limit Preplacement surveillance

Focus on respiratory system, cardiovascular, GI, PFT’s CXR Asbestos questionnaire Respirator standard

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Asbestos (continued)

Periodic surveillance Abbreviated OSHA asbestos questionnaire/CXR according to

schedule below

Yrs since first exposure

Age 15-35 yrs

Age 35+ to 45

Age 45+

0-10 Every 5 years Every 5 years Every 5 years

10+ Every 5 years Every 2 years Every 1 year

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Mineral Fibers: Asbestos and Ceramic Fibers/Man-Made Mineral Fibers (MMMF)

Ceramic Fibers One of a group of insulating materials known as MMMF Produced from aluminum oxide, silicon oxide and other metal

oxides PEL for respirable dust is 5mg/m3; Exposure limit of 1fiber/cc as

a TWA for ceramic fibers Surveillance

Medical/occupational histories with emphasis on the skin and respiratory tract

Physical exam Chemistries, blood count, PFT, CXR

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Hydrofluoric Acid Intermediate in production of fluorocarbons, aluminum fluoride,

cryolite; in production of uranium hexafluoride; metal cleaning, glass etching, polishing applications; occupational exposure can occur both by direct skin contact and by inhalation of fumes

Corrosive: causes calcium precipitation, stimulate nerve endings; binds body calcium causing life threatening systemic hypocalcemia after skin exposure or osteosclerotic bone changes after chronic exposure to HF ions; treat skin exposure with calcium gluconate

Workers with evidence of renal disease, impaired pulmonary function, scarring of the skin or cornea or osteosclerosis should be evaluated by a physician and if appropriate, informed of possibility of increased health risk from HF exposure.

Nonemergent exposures: UA, skin, cornea exams, hip xray (for males) should be offered Respiratory irritation: CXR, PFT Eye complaints: visual acuity/ophthalmological examination

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Hydrofluoric Acid Biological monitoring

ACGIH TLV – 3.0ppm 8-hr TWA and STEL 6ppm Preshift spot urinalysis

Collect at start of work shift at least 48 hrs after the last occupational exposure

Post shift urinalysis Evaluates accumulation of fluoride Collect at end of workshift after (4) consecutive days of exposure

If post shift urinary fluoride level exceeds 7.0mg/L, preshift spot urine samples for analysis should be collected within 2 weeks and a repeat post shift urinalysis If second sample is > the preshift limit of 4.0mg/L or post shift limit of

7.0mg/L, evaluated dietary sources, personal hygiene, basic work practices and environmental control

Job classification: evaluate all workers urinary fluoride levels on a group basis – if median post shift urinary fluoride levels >7.0mg/L, proceed with IH survey

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Cyanide Available as gas and technical liquid (3) most common cyanide salts: sodium, potassium, calcium Cyanide inhibits transfer of oxygen to cells OSHA PEL for cyanide salts is 4.7ppm; for potassium cyanide – 10ppm Acute exposure:

Lesser exposure: irritation of eyes, nose, throat, weakness, H/A, confusion, respiratory abnormalities, coma, convulsion

Minor symptoms after several minutes at breathing levels of 10-30ppm Death within an hour at level of 100ppm

Chronic exposure: Symptoms may persist for several months following cessation of exposure

Surveillance: Medical and occupational histories to evaluated any chronic effects: H/A,

nausea, dizziness; emphasis on skin, cardiovascular, pulmonary edema Periodic surveillance on basis of workers exposure potential to cyanides and

judgement of the physician Treatment: amyl nitrate by inhalation, followed by sodium nitrate

intravenously, then sodium thiosulfate IV

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Biological Monitoring Measurement of a chemical, its metabolite, or a nonadverse

biochemical effect in a biological specimen for the purpose of assessing exposure

Blood, urine, exhaled air Measures total exposure ( quantity of chemical absorbed regardless

of route of administration) vs workplace exposure (environmental monitoring)

Assesses the extent of exposure, therefore only an indirect measurement of risk of health effects as a result of exposure

Necessary conditions to consider biological monitoring Determinant must be present in blood, urine, exhaled air; suitable for

sampling; acceptable sampling method Method of analysis should be practical, produce valid reproducible

results over the range of concentrations Strategy of sample collection produces representative samples Results can be interpreted Action required for aberrant result established prior to monitoring

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Biological Monitoring

Methodology: Timing of Collection is critical

For chemicals with a short t1/2, the difference between sampling 15 minutes vs 1 hour after the end of exposure may alter the result by as much as a factor of 10.

Collection methods: proper containers, contamination with unwashed hands or clothing

Body site sampled Blood: most accurate

Volatile substances with short t1/2, have a variation in blood level Urine: easier to sample

24 hour urine most accurate Spot urine most practical; have to adjust for urine specific gravity or

Creatinine; Highly concentrated (SpG>1.030 or Cr>3g/L) or highly dilute (Spg<1.010 or CrM0.3-0.5g/L) usually not suitable for monitoring and a new specimen should be collected

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Biological Monitoring Methodology (continued)

Exhaled air Measurements of chemicals in exhaled air are with mid – exhaled or

end-exhaled Selecting a Lab

Only national certification in US if for blood lead California – only state with state certified labs for state mandated

cholinesterase testing for pesticide handlers WHO has conducted international quality assurance program for

blood lead and urine cadmium determinations Terminology

No Adverse Health Effect Level: level at which almost all workers will be free of symptoms, signs and adverse clinical lab test results Repro and Ca effects are not considered when calculating this level.

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Biological Monitoring

Terminology (continued) BEI (Biological exposure indices): level that corresponds to the level

measured in a worker exposed to a substance at the TLV-TWA; reference biological monitoring levels established by the ACGIH

Clinical Effect Level: level associated with signs, symptoms, abnormal lab tests

Timing of collection: most important for determination of the No Adverse Health Effect Level If t1/2 (rate of elimination of an agent) is short (min-hours), timing of critical; if

long (days to weeks) timing not critical Relative to standard work day and work week

PNS – Prior to next shift = 16 hrs after last shift EOS – End of shift = 15-30 minutes after the last exposure DS – during shift EWW – end of work week L2H – last 2 hrs of shift L4H – last 4 hrs of shift

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Who Needs the DOT Medical Card? Federal Motor Carrier Safety Regulations

(FMCSRs): Commercial Motor Vehicle

16 or more passengers including driver Transports hazardous materials Vehicle weight

10,001-26,000 lbs Medical card

26,001 or greater Medical card Drug and alcohol testing CDL license

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Automatic Disqualifications

Epilepsy Hearing loss not correctable by hearing aid Current diagnosis of alcoholism Vision deficit

Must have 20/40 both eyes, peripheral vision > 70 degrees

Methadone use

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Potential Disqualifications Monocular vision Hypertension Loss of limb Musculoskeletal disorder Heart condition Respiratory condition Psychiatric illness Controlled substance use

Narcotics, benzodiazepines

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Insulin Dependent Diabetes Update September 3, 2003

Type I diabetes no longer automatic disqualifier Significant documentation and specialist visits

required to complete application for exemption on part of driver

Must have annual exam by endocrinologist AND DOT recertification

Must comply with rules for diabetic control as set forth by FMCSA

http://a257.g.akamaitech.net/7/257/2422/14mar20010800/edocket.access. gpo.gov/2003/03-22409.htm

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New Guidelines for Cardiovascular Conditions

Oct. 2002 Conference on Cardiac Disorders and CMV drivers Shorter time for recertification post-MI Test of cardiac ejection fraction for many

conditions Implantable defibrillator disqualification

http://www.fmcsa.dot.gov/rulesregs/cardio.htm

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Blood Pressure Guidelines Part 391 Federal Register-Qualifications of

Drivers In effect as of 9/30/04 Diagnosis of hypertension on medication requires

more frequent certification BP should be measured on 3 separate occasions

while sitting to make determination of high BP If driver has no history of hypertension and has a

BP of 140/90, he can be certified for up to 2 years on initial examination.

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New Blood Pressure Guidelines for Drivers with Diagnosis of Hypertension Stage 1: 140/90-159/99

Certify one year Stage 2: 160/100-179/109

3-month certificate, treat, re-evaluate If BP at 3 months <140/90 recertify annually

Stage 3: 180/110 No certification until BP 140/90 Then recertify every 6 months

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Periodic Evaluation of Hypertensive Drivers Periodic screening and evaluation for “target

organ” damage Heart failure Stroke Retinopathy Kidney damage Coronary artery disease

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Heart Conditions: Ischemia

Focus: strength of the heart and risk of irregular heart beat (arrhythmia)

Risk factors: HTN, tobacco, Chol, LDL, DM, obesity, inactivity,

family history, >60yrs old, male, postmenopausal women

Truck drivers may have increased number of risk factors – sedentary job, irregular hours, dietary habits

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Heart Conditions: Myocardial Infarction (MI) New definition

Joint European Society/American College of Cardiology Committee in 2000

More people meet criteria for an MI due to increased accuracy in diagnoses Elevated troponin levels but no elevation of CPK-MB

2 month wait period after MI rather than 3 months ETT 4-6 weeks post MI, repeat every 2 years Ejection fraction must be > 40% No medication side effects

Recertification annually

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Heart Conditions: Angina

Annual recertification

ETT at least every 2 years

No angina at rest

Stable blood pressure

No medication side effects

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Heart Conditions: Percutaneous Coronary Interventions RTW 1-week post-procedure for stable

angina, unstable same as MI protocol ( 3 months)

ETT 3-6 months post-procedure and at least every 3 years

Stable blood pressure No medication side effects

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Coronary Artery Bypass Surgery 3 month waiting period

Must be stable on medication for at least 1 month

ETT annually

Resting EKG

Ejection fraction > 40%

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Heart Conditions: Arrhythmias Atrial fibrillation and Ventricular Tachycardia

Stable 1 month on medication Annual certification Blood thinners not necessarily disqualifying

WPW and Long QT syndrome: automatic disqualification

Pacemakers If underlying disease is not disqualifying certify

after 3 months Annual recertification

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Valvular Heart Disease

Cardiology evaluation EKG, chest x-ray, ETT, Echocardiogram

Types: Mitral stenosis, Mitral regurgitation Aortic stenosis, Aortic regurgitation

If no disqualifying factors (valve area and symptoms) than annual recertification

Repeat testing may be needed from every 6-12 months to every 5 years

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Vascular Disease

Abdominal aneurysms >5cm disqualifying 4-5cm disqualifying if symptomatic or pending

surgery <4cm – recertify annually if asymptomatic and no

surgery planned; annual Ultrasound to monitor size

3 month wait after surgery

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Peripheral Vascular Disease Generally not disqualifying unless resting

pain in lower extremities

3 month waiting period after vascular surgery


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Deep Vein Thrombosis

Disqualifying unless adequately treated

On medication at least one month such as Coumadin with monthly blood testing


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Heart Transplantation

Can consider certification after 1 year waiting period

Recertification every 6 months

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Respiratory Dysfunction Qualified to drive a commercial motor vehicle if

“…no medical history or clinical diagnosis of a respiratory dysfunction likely to interfere with ability to control and drive a CMV.” Sec.391.41(b)(5)

Impairment in respiratory function under emergency conditions (when greater oxygen supply is necessary for performance) may be detrimental to safe driving

If the medical examiner detects a respiratory dysfunction that in any way is likely to interfere with the drivers ability to drive, the driver must be referred to a specialist for evaluation and treatment

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Respiratory Dysfunction: Sleep Apnea Included in the advisory criteria as a respiratory condition that “may result in incapacitation”

Resulting daytime somnolence/decreased alertness is potential cause of MVA 2-4 fold increase in MVA in untreated sleep apnea

New medical exam form addresses sleep disorders

100,000 – 150,000 commercial drivers have sleep apnea

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Respiratory Dysfunction: Sleep Apnea Affects 2-3% of adult males

Obese, middle-aged males 3 key risk factor

BMI>28 Hypertension Neck size >17” ( increased neck circumference)

Other risk factors Alcohol History of snoring

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Respiratory Dysfunction: Sleep Apnea If any suspicion – refer for evaluation Medically unqualified until successfully treated

Surgery CPAP-waiting period of at least 30 days prior to

certification Weight loss

Annual Multiple Sleep-Latency Testing (Polysomnograph)

Follow-up in 1-2 months to assess effectiveness of treatment

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Other Worker Groups

The Biotech Industry Infectious agents, chemicals, carcinogens, radioisotopes, product

hazards, animal handling, reproductive hazards Healthcare workers

Latex allergy, anesthetic gases, chemical hazards, cytotoxic drugs, ergonomics, bloodborne pathogens

Municipal workers Sewage workers: biological hazards, bacteria, confined spaces,

chemicals, cancer risk Police and corrections: stress, ischemic heart disease, BBP, shift work,

chemical hazards, cancer risk Firefighters: chemical exposure, respiratory issues, physical

requirements, stress, biological exposure Bridge and Tunnel workers: Vehicular exhaust,/respiratory and cardiac

disease, ergonomics, temperature, noise, shift work, chemicals, microwave radiation

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References A Practical Approach to Occupational and Environmental

Medicine, 3rd Ed. McCunney RJ, Rountree PP, eds. Lippincott Williams and Wilkins, 2003

Current Occupational and Environmental Medicine, 3rd Ed. LaDou J, McGraw-Hill/Appleton & Lange, 2004

Fundamentals of Industrial Hygiene, 3rd Ed. Plog BA, Quinlan PJ, eds National Safety Council, 1988

Guide to the Medical Evaluation for Respirator Use. McLellan R, Schusler K, OEM Press, 2000

Instant Medical Surveillance, Mitchell FL, OEM Press, 2002

A DOT Medical Examination: A Guide to Commercial Drivers’ Medical Certification, 3rd Ed. Hartenbaum NP, OEM Press, 2003

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Be Safe!

Tony Soares, Safety Director

Compensation Solutions, Inc.

[email protected]: 1-888-201-5680 Ext. 192

Documents

The ABCs of Medical Surveillance