57 Occupational Diseases: Definition and Recognition, Common Diseases (Silicosis, Asbestosis, Byssinosis, Pneumoconiosis, Lead/Mercury Poisoning, Noise-Induced Hearing Loss, Repetitive Strain Injury), Third Schedule Factories Act, Schedule III Employees’ Compensation Act, ESI Disablement Benefit and the Code on Social Security 2020
57.1 When Work Itself Becomes Illness
An occupational disease is an illness caused or substantially contributed to by exposure to risk factors at work. Unlike an injury, it usually has a long latent period — silicosis may appear ten or twenty years after exposure ceases. The Indian framework identifies notifiable diseases in the Third Schedule of the Factories Act 1948 (post-1976) and the Schedule III of the Employees’ Compensation Act 1923; ESI Act 1948 pays disablement benefit; the OSH&WC Code 2020 carries forward the regime.
57.2 1 · Definition
TipDefinitions
| Source | Substance |
|---|---|
| ILO | Any disease contracted as a result of an exposure to risk factors arising from work activity |
| WHO | Disease arising out of and in the course of employment |
| Indian law | “Notifiable occupational disease” listed in Third Schedule of Factories Act and Schedule III of Employees’ Compensation Act |
57.3 2 · Distinction from Industrial Accident
TipDisease vs Injury
| Aspect | Industrial Disease | Industrial Accident |
|---|---|---|
| Onset | Gradual / latent | Sudden |
| Cause | Long-term exposure | Identifiable event |
| Proof of causation | Often difficult | Usually clear |
| Examples | Silicosis, asbestosis | Fall, burn, crush injury |
57.4 3 · Common Occupational Diseases
57.4.1 A · Pneumoconioses (Dust Lung Diseases)
TipMajor Pneumoconioses
| Disease | Cause | Affected Workers |
|---|---|---|
| Silicosis | Inhalation of crystalline silica | Mining, foundry, stone-crushing, sand-blasting, agate, slate-pencil |
| Asbestosis | Asbestos fibres | Asbestos mining, manufacturing of brake-lining, roofing |
| Coal Workers’ Pneumoconiosis (Anthracosis / Black Lung) | Coal dust | Coal mining |
| Byssinosis (Brown Lung) | Cotton, flax, hemp dust | Textile, jute, cotton ginning |
| Bagassosis | Bagasse (sugar-cane fibre) | Sugar mills |
| Siderosis | Iron oxide | Iron and steel industry |
| Stannosis | Tin oxide | Tin mining |
| Berylliosis | Beryllium | Electronics, aerospace |
57.4.2 B · Metal Poisoning
TipMetal Poisoning
| Metal | Disease / Effect | Workers |
|---|---|---|
| Lead | Plumbism — anaemia, abdominal colic, neuropathy, fertility | Battery, paint, printing, smelting |
| Mercury | Hydrargyrism — tremor, gingivitis, “mad hatter’s disease” | Thermometer, dental, mining |
| Manganese | Manganism — Parkinson-like symptoms | Manganese mining, ferro-alloy |
| Cadmium | Itai-itai disease (bones), lung | Battery, plating |
| Chromium | Chrome ulcer of skin and nasal septum | Tanning, plating |
| Arsenic | Skin lesions, peripheral neuropathy | Smelting, pesticide |
57.4.3 C · Solvent and Chemical Disorders
- Benzene — leukaemia, aplastic anaemia.
- Toluene — neurotoxicity.
- Trichloroethylene — liver damage.
- Vinyl chloride — angiosarcoma of liver.
- Pesticides — cholinesterase inhibition (acute) and chronic neurotoxicity.
57.4.4 D · Physical-Agent Diseases
- Noise-Induced Hearing Loss (NIHL) — prolonged exposure >85 dB(A); irreversible.
- Hand-Arm Vibration Syndrome (HAVS) — pneumatic drills.
- Heat-related illnesses — heat stroke, heat exhaustion, heat cramps.
- Radiation injuries — acute, cancer.
- Decompression sickness — divers, caisson workers.
57.4.5 E · Biological
- Anthrax — tannery, wool sorter.
- Brucellosis — veterinary, dairy.
- Leptospirosis — sewer, agriculture.
- Tuberculosis — healthcare.
57.4.6 F · Ergonomic / Musculoskeletal
- Repetitive Strain Injury (RSI) — typists, assembly-line.
- Carpal Tunnel Syndrome.
- Low Back Pain — manual handling.
- Cervical and lumbar spondylosis.
57.5 4 · Indian Notifiable Occupational Diseases
57.5.1 Third Schedule, Factories Act 1948
The Third Schedule (added 1976, expanded periodically) lists notifiable occupational diseases. Some include:
- Lead poisoning.
- Phosphorus poisoning.
- Mercury poisoning.
- Manganese poisoning.
- Arsenic poisoning.
- Carbon disulphide.
- Benzene.
- Chrome ulceration.
- Silicosis.
- Asbestosis.
- Pathological manifestations due to radioactive substances and X-rays.
- Pneumoconiosis.
- Byssinosis.
- Anthrax.
- Occupational cancer (skin, lung from arsenic, chromium, asbestos).
57.5.2 Schedule III, Employees’ Compensation Act 1923
Schedule III lists occupational diseases (Part A, B, C) for compensation:
- Part A — minimum 6 months’ service in scheduled employment.
- Part B — diseases for which substantial proof needed.
- Part C — diseases with longer minimum exposure.
57.5.3 Section 89, Factories Act — Notification
Medical practitioners must notify the Chief Inspector of Factories of any case of an occupational disease specified in the Third Schedule.
NotePYQ trap — Section 89 / Third Schedule
Notification of occupational disease is mandatory under Section 89 read with the Third Schedule of the Factories Act 1948.
57.6 5 · Compensation Framework
57.6.1 Employees’ Compensation Act 1923
- Section 3(2) — occupational diseases treated as injuries by accident.
- Schedule III — list of occupational diseases.
- Compensation as per Schedule IV:
- Death — 50 % of monthly wage × relevant factor (age-based), minimum Rs 1.2 lakh.
- Permanent total disablement — 60 % × relevant factor, minimum Rs 1.4 lakh.
57.6.2 ESI Act 1948
For workers covered under ESI:
- Disablement benefit — 90 % of wages during temporary disablement; periodical payment for permanent.
- Dependants’ benefit — on death.
- Medical benefit — full treatment.
57.7 6 · Prevention Framework
TipPrevention of Occupational Diseases
| Stage | Measure |
|---|---|
| Primary | Substitute hazardous substances; engineering controls (LEV, dust suppression); PPE; pre-employment screening |
| Secondary | Periodic medical examination; early detection (chest X-ray for silica workers, audiometry for noise) |
| Tertiary | Treatment, rehabilitation, redeployment |
57.8 7 · Recent Indian Concerns
TipIndian Hotspots
| Issue | Substance |
|---|---|
| Silicosis in Rajasthan | Stone-mining/quarrying clusters — Karauli, Jodhpur, Dhaulpur; Rajasthan launched silicosis policy 2019 (then 2023 updated) — pension of Rs 1,500/month + compensation |
| Asbestos | India is still a major importer; ban demand long-standing |
| Pesticide poisoning | Punjab, Vidarbha agricultural workers |
| Pneumoconiosis in coal | Jharia/Dhanbad |
| Itai-itai in Tamil Nadu | Cadmium discharge in Kalpakkam area (alleged) |
| Brick kiln workers | Heat illness, silicosis |
| Beedi rolling | TB, musculoskeletal disorders |
57.9 8 · International Recognition
- ILO Convention C-121 (1964) — Employment Injury Benefits (with revised schedule of occupational diseases).
- ILO list of occupational diseases (revised 2010) — covers chemical, physical, biological agents, target organs, mental & behavioural disorders, cancer.
57.10 9 · Position under the OSH&WC Code 2020
The Code:
- Carries forward the list of notifiable occupational diseases (via schedule).
- Provides for medical examination — free for workers above 45.
- Mandates reporting to authorities.
57.11 Practice Questions
Q 01SilicosisEasy
Silicosis is caused by:
View solution
Correct Option: B
Crystalline silica.
Q 02ByssinosisMedium
Byssinosis ("brown lung") is caused by inhalation of:
View solution
Correct Option: A
Cotton-dust disease.
Q 03MatchHard
Match disease with cause:
| (i) | Anthracosis | (a) | Asbestos |
| (ii) | Bagassosis | (b) | Coal dust |
| (iii) | Asbestosis | (c) | Iron oxide |
| (iv) | Siderosis | (d) | Bagasse |
View solution
Correct Option: A
Anthracosis-coal; Bagassosis-bagasse; Asbestosis-asbestos; Siderosis-iron.
Q 04Mad hatterMedium
"Mad hatter's disease" is caused by:
View solution
Correct Option: B
Mercury — hatters using mercuric nitrate for fur felting.
Q 05Itai-itaiHard
Itai-itai disease is caused by:
View solution
Correct Option: A
Cadmium poisoning, originating in Japan.
Q 06BenzeneHard
Benzene exposure is most strongly associated with:
View solution
Correct Option: A
Haematological cancers.
Q 07AnthraxMedium
Anthrax in occupational settings is most associated with:
View solution
Correct Option: A
"Woolsorter's disease".
Q 08Section 89Medium
Notification of occupational disease under the Factories Act 1948 is mandatory under:
View solution
Correct Option: D
Section 89 — notification of disease.
Q 09Third ScheduleMedium
Notifiable occupational diseases are listed in:
View solution
Correct Option: C
Third Schedule.
Q 10Schedule III ECAMedium
Under the Employees' Compensation Act, occupational diseases are listed in:
View solution
Correct Option: C
Schedule III in three parts.
Q 11NIHLMedium
Noise-Induced Hearing Loss generally occurs after sustained exposure to:
View solution
Correct Option: C
>85 dB(A) over time.
Q 12ILO C-121Hard
ILO Convention 121 (1964) deals with:
View solution
Correct Option: A
C-121 Employment Injury Benefits.
Q 13PneumoconiosisMedium
Pneumoconioses are diseases of:
View solution
Correct Option: B
Dust-induced lung diseases.
Q 14ChromeHard
Chrome ulcer is a notifiable occupational disease in workers handling:
View solution
Correct Option: A
Chromium exposure.
Q 15PlumbismMedium
Plumbism is poisoning by:
View solution
Correct Option: A
Lead poisoning.
Q 16RajasthanHard
Rajasthan's silicosis policy (2019) provides:
View solution
Correct Option: A
Pension + lump sum + dependents' compensation.
Q 17Vinyl chlorideHard
Vinyl chloride exposure causes:
View solution
Correct Option: A
Hepatic angiosarcoma.
Q 18OrderHard
Arrange in order — prevention stages for occupational disease (most to least preferred):
View solution
Correct Option: A
Hierarchy of controls.
Q 19BrucellosisHard
Brucellosis is an occupational risk in:
View solution
Correct Option: A
Veterinary, dairy, abattoir.
Q 20Code 2020Easy
Occupational disease provisions are now consolidated in:
View solution
Correct Option: B
OSH&WC Code 2020 (and Code on Social Security for compensation).
57.12 Quick Recall
ImportantQuick recall
- Occupational disease — caused by exposure to risk factors at work; long latent period.
- Pneumoconioses: Silicosis (silica), Asbestosis (asbestos), Anthracosis (coal), Byssinosis (cotton), Bagassosis (bagasse), Siderosis (iron), Stannosis (tin), Berylliosis (beryllium).
- Metal poisoning: Lead (Plumbism), Mercury (Mad-hatter), Cadmium (Itai-itai), Manganese (Parkinson-like), Chromium (ulcer), Arsenic (skin lesions).
- Solvent/Chemical: Benzene → leukaemia; Vinyl chloride → liver angiosarcoma; Pesticides → cholinesterase inhibition.
- Physical: NIHL >85 dB(A); HAVS; Heat illness; Radiation; Decompression sickness.
- Biological: Anthrax (woolsorter’s), Brucellosis (dairy/vet), Leptospirosis (sewer), TB (healthcare).
- Ergonomic: RSI, Carpal tunnel, Low back pain, Cervical/lumbar spondylosis.
-
Indian framework:
- Third Schedule, Factories Act — notifiable diseases.
- Section 89 Factories Act — notification.
- Schedule III, Employees’ Compensation Act 1923 — three Parts (A/B/C).
- ESI Act 1948 — disablement benefit at 90 % of wages.
- ILO C-121 (1964) — Employment Injury Benefits; ILO list of occupational diseases revised 2010.
- Rajasthan silicosis policy 2019 — pension + lump-sum benefits.
- OSH&WC Code 2020 — consolidates occupational disease regime.