BYSSINOSISBYSSINOSISHealth Hazards from Cotton DustHealth Hazards from Cotton Dust

Dr. Shobha MisraDr. Shobha MisraAssociate Prof.Associate Prof.

Dept. of P & S.M.Dept. of P & S.M.

Medical College BarodaMedical College Baroda

BYSSINOSISBYSSINOSISHealth Hazards from Cotton DustHealth Hazards from Cotton Dust

Dr. Shobha MisraDr. Shobha MisraAssociate Prof.Associate Prof.

Dept. of P & S.M.Dept. of P & S.M.

Medical College BarodaMedical College Baroda

Cotton Dust Cotton dust is defined as dust

generated into the atmosphere as a result of processing of cotton fibres combined with any naturally occurring materials such as stems, leaves bracts and inorganic matter which may have accumulated on the cotton fibres during the growing of harvesting period.

Health Hazards from Cotton Dust

What is Byssinosis? Byssinosis caused by inhalation of vegetable dust

(Cotton, Flax, Soft hemp) is a continuing problem and occurs worldwide.

Who gets Byssinosis?

Symptoms of Byssinosis

Three stages

- The stage of irritation- The stage of temporary disablement

or incapacity- The stage of total disablement or

incapacity

Prevalence of Byssinosis

compared to dust exposure Total dust Prevalence No. of people Exposure (all grades of examinedMg/cu.m. Byssinosis) 0-0.5 1.5% 2120.5-1.0 2.8% 1081.0-2.0 9.9% 1,2592.0-3.0 8.5% 12263.0-4.0 34.0% 4654.0-5.0 55.0% 2455.0-(34.0) 27.5% 92 Total

3607From British occupation hygiene society committee on Hygiene

standards(1972)

Cotton dust: Size and deposition site Ayer (1971)

Constituent Aerodynamic Remarksdiameter(um)

Lint and fuzz fibres > 20 Essentially no deposition in respiratory tract

Vegetable trash >15 Essentially no deposition in respiratory tract

Vegetable trash 8-15 Mainly eronasal and tracheal deposition

Vegetable trash < 8 Some deposition in pulmonary spaces,preposition increasing as size decreases

Mineral matter <8 Some deposition in pulmonary spaces,preposition increasing as size decreases

Air pollution < 8 Some deposition in pulmonary spaces,preposition increasing as size decreases

Grading of Byssinosis according to schilling’s description WHO

1983

GRADE SYMPTOMS0 No symptoms½ Occasional chest tightness or cough on the first day of

the working week

I Chest tightness and/or shortness of breath on every first day of the working week

II Chest tightness and/or shortness of breath on the first day and other days of the working week

III Grade-II symptoms accompanied by evidence of permanent loss of lung functions.

In new classification proposed by WHO grade ½ bysinosis has been omitted.

Effects of Byssinosis

Acute

Chronic

DefinitionAcute changes in lung functions (FEV1/PEFR)Change Category DefinitionA. Acute No effect A consistent decline in FEV1 upto

5% OR an increase in FEV1 during the work shift.

Mild effect A consistent decline in FEV1upto10% during the work shift

Moderate effect A consistent decline in FEV1between 11% -20% during the

work shiftSevere effect A decline in FEV1 of more

than 20% during the work shift.

Chronic changes

Category Definition

No effect(Normal) FEV1 80% of predicted value

Mild to moderate FEV179% to 60% ofpredicted value

Severe effect FEV1 <60% of predictedvalue

This classification is based on the recommendations of health based occupational exposure limits of selected vegetable dust WHO 1983

Pathogenesis

Diagnosis and treatment

Classification of work area by total dust concentration Roach and Schilling (1960)Grade of dustiness Concentration

(total dust))A. Safe with medical < 1 mg/mm. Supervision of work areaB. Dust control desirable 1-2.5 mg/mm. and medical control essentialC. Dust control and >2.5mg/mm. medical supervision essential

Can Byssinosis be prevented?

A Engineering methods:a)Environmental dust control

a)Humidification

a)Oiling in cotton

a)Proper use of exhaust systems and production machinery

B Medical measures :

a) Need for periodical medical examination

b) Use of respirators and face masksc) Informing employees of hazards from cotton dust d) Specific work habitse) General house keepingC Statutory Methods :• Workmen’s compensation and

social security benefits.

RESPIRATORY MORBIDITY IN THE WORKERS OF A TEXTILE INDUSTRY OF BARODA CITY

Misra Shobha V. Kotecha P.V.

Joshi G.D.

Dept. of Preventive and Social Medicine,

Medical College, Baroda, Gujarat

Sections in a Textile mill

Three important sections:• Spinning• Weaving• Processing

Spinning has 4 sub-sections:• Blow• Card• Frame• Ring-frame

Objectives • To measure acute and chronic changes

in pulmonary functions due to exposure to cotton dust.

• To find out the prevalence of byssinosis in textile workers.

Methodology• A cross-sectional study • carried out in different departments of a

textile mill of Baroda city and • healthy controls for assessment of acute and

chronic changes in ventilatory functions and prevalence of Byssinosis due to exposure of cotton dust

• A standard questionnaire was administered • Pre and post shift lung function tests were

measured for each worker

Environmental Assessment

• The dust sampling was done using a vertical elutriator specifically designed to collect cotton dust.

• The design required a flowrate of 7.4 lpm and particles less then 15u in size were sampled.

• 2 hour samples were taken from two sections. – One near the Willow machine (blow room) and – other from spinning section.

• Dust sampling was done by Industrial Hygiene Laboratory (IHC), Ahmedabad on 1st May 1994.

Results

Exposed Workmen In Different Departments Of Textile Industry

Prevalence of Different Grades Of Byssinosis*

*Schilling’s Classification of Byssinosis WHO 1993

Chronic Changes in FEV1 in the Subjects

Departmentwise

PFT Values In Byssinotics And Non-Byssinotics

*Indicate Significant Values (P< 0.01)

Chronic Changes*In FEV1 And PEFR In

Byssinotics & Non-Byssinotics

PFT Values In Byssinotics & Non-Byssinotics Pre And Post-Shift (Acute-

Change)

Acute Changes* In FEV1 And PEFR In Non-Byssinotics And

Byssinotics

Dust Concentration In Different Sections Of The Cotton Textile

Mill

RECOMMENDATIONS

• Medical measures: Pre-employment examination, retesting of newly employed workers for ventilatory capacity within 6 weeks on first day of work (after 40 hours absence from exposure) pre-shift and post- shift should be carried out.

• Those having predicted value of FEV1 < 80 per cent and acute change >5 per cent should be re-evaluated after 6 months and those having FEV1 <60 per cent and acute change >10 per cent should be excluded from exposure. All workers should be offered medical examination and PFT yearly thereafter.

RECOMMENDATIONS, contd…

• Engineering methods: There is a need to prevent dust of respirable size by good house-keeping and adequate use of appropriate exhaust system. Evaluation of workplace conditions every 6 months and environmental monitoring with regard to dust standards of ACGIH18 is advisable.

• Statutory methods: Standards set by governmental agencies for acceptable levels of dust concentration and enforcement of the same. Notification of disease of earlier stages also.

• Further Research: Including a nation-wide survey of textile mills with special reference to disease in non-smokers is suggested. The need for an effective control programme is suggested to see that byssinosis suspects are properly examined and given proper treatment.

References

• WHO Report Recommended health-based occupational exposure limits for selected vegetable dust. Report of WHO study group 1983; TRS 684.

• Schilling RSF. World wide byssinosis, British Med. J. 1962; II: 781.

• Bouhuys A, et al. Byssinosis in cotton textile workers. Respiratory survey of a mill with rapid labour turnover. Annual International Medicine 1968; Vol 71: (No 2) : 257-269.

Thank You