OD Intro & ILO - Work Woes 101
- Occupational Disease (OD): Illness caused by workplace exposure.
- Causal Relationship: Direct link between work hazard & disease.
- ILO List: International Labour Organization maintains a list of ODs.
- Key Indian Acts: (📌 FEW Acts)
- Factories Act, 1948
- ESI Act, 1948
- Workmen's Compensation Act (now Employee's), 1923
⭐ ILO defines occupational disease as a disease contracted as a result of an exposure to risk factors arising from work activity.
Pneumoconioses - Dusty Lung Diaries
Occupational lung diseases caused by inhalation of mineral or organic dusts.
| Disease | Agent | Occupations | Key Features/CXR |
|---|---|---|---|
| Silicosis | Free silica ($SiO_2$) | Mining, sandblasting, pottery, quarrying | 'Snow storm' appearance, 'egg-shell' calcification of hilar nodes; Caplan’s syndrome, ↑TB risk. |
| Coal Worker's Pneumoconiosis (CWP) | Coal dust | Coal mining | Simple CWP (macules), Progressive Massive Fibrosis (PMF), melanoptysis. Caplan's syndrome. |
| Asbestosis | Asbestos fibers | Shipbuilding, insulation, construction, mining | Basal lung fibrosis, pleural plaques (parietal), ↑risk of bronchogenic carcinoma & mesothelioma, ferruginous bodies. |
| Byssinosis | Cotton, flax, hemp dust | Textile industry | 'Monday fever': chest tightness, dyspnea on first day of work week. |
| Bagassosis | Mouldy sugarcane bagasse (thermophilic actinomycetes) | Sugar cane industry | Hypersensitivity pneumonitis: fever, cough, dyspnea 4-6 hours post-exposure. |
| Farmer's Lung | Mouldy hay/grain (e.g., Micropolyspora faeni) | Farming | Hypersensitivity pneumonitis: acute (fever, chills, cough) or chronic (fibrosis). |
⭐ Egg-shell calcification of hilar lymph nodes is characteristic of silicosis.
📌 Mnemonic for Asbestos complications: LAMP (Lung cancer, Asbestosis, Mesothelioma, Pleural plaques).
Chemical Poisonings - Toxic Takeover
| Toxin | Occupations | Key Clinical Features | Dx Marker / Treatment |
|---|---|---|---|
| Lead (Pb) | Battery, paints, smelting | Burton's line, wrist/foot drop, encephalopathy, anemia. 📌 LEAD: Lead lines, Encephalopathy, Anemia, Drop. | ↑ALA (urine), Basophilic stippling. Chelation: EDTA, DMSA. |
| Mercury (Hg) | Thermometers, dental, fungicides | Minamata, erethism (mad hatter), tremors, acrodynia. | ↑Urine Hg. Chelation: DMPS, DMSA. |
| Arsenic (As) | Pesticides, smelting, groundwater | Mees' lines, hyperkeratosis (palms/soles), cancers (skin, lung). | ↑Urine As. Chelation: BAL, DMSA. |
| Cadmium (Cd) | Electroplating, batteries | Itai-itai disease, nephrotoxicity, osteomalacia. | ↑Urine Cd, ↑β2-microglobulin. Supportive. |
| Benzene | Petrochemicals, solvents | Bone marrow suppression, aplastic anemia, leukemia risk. | CBC (pancytopenia). Remove exposure. |
| Carbon Monoxide (CO) | Incomplete combustion (fires, exhaust) | Headache, confusion, cherry-red skin, coma. | ↑COHb. 100% O2, hyperbaric O2. |
⭐ Basophilic stippling of RBCs is a characteristic feature of lead poisoning.
Cancers & Other Hazards - Beyond the Fumes
Occupational Cancers:
| Agent | Target Organ | Common Occupations |
|---|---|---|
| Asbestos, Silica, Arsenic, Radon | Lung | Mining, Construction |
| Aromatic amines/dyes | Bladder | Dye, Rubber industry |
| UV, Tar, Soot | Skin | Outdoor workers, Chimney sweeps |
| Benzene, Radiation | Leukemia | Chemical, Nuclear industry |
| Asbestos | Mesothelioma | Shipbuilding, Insulation |
- Noise Induced Hearing Loss (NIHL): Sensorineural, **4kHz** dip.

> ⭐ Acoustic dip at **4000 Hz** is characteristic of Noise-Induced Hearing Loss.
- Vibration Syndrome: HAVS (Hand-Arm), Raynaud's phenomenon.
- Radiation: Ionizing/non-ionizing effects.
- Biological Hazards: (Briefly) Anthrax - woolsorter's; Brucellosis - farmers, vets; Leptospirosis - sewer workers, farmers.
Prevention & Control - Safety Shield Strategies
- Hierarchy of Controls: Prioritizes hazard removal. 📌 Every Student Excels At P.E. (Elimination, Substitution, Engineering, Admin, PPE).
> ⭐ Elimination is the most effective measure in the hierarchy of controls for occupational hazards.
- Medical Measures:
- Pre-placement & Periodical medical examinations
- Health education for workers
- Monitoring sickness absenteeism trends
- Notification: Certain occupational diseases must be notified (e.g., under Factories Act, 1948).
High‑Yield Points - ⚡ Biggest Takeaways
- Pneumoconioses: Lung diseases from inhaled inorganic dusts (silica, coal, asbestos).
- Silicosis: Mining, sandblasting; egg-shell calcification, ↑ TB risk.
- Asbestosis: Insulation, shipbuilding; pleural plaques, bronchogenic Ca (commonest), mesothelioma. Ferruginous bodies.
- Byssinosis: Cotton/flax/hemp dust ("Monday Fever"); reversible bronchoconstriction.
- Lead Poisoning: Paints, batteries; Burton's line, wrist drop, basophilic stippling. Chelation: EDTA/DMSA.
- Farmer's Lung: Hypersensitivity pneumonitis from moldy hay (thermophilic actinomycetes).
- Benzene: Occupational exposure linked to aplastic anemia and AML.
Continue reading on Oncourse
Sign up for free to access the full lesson, plus unlimited questions, flashcards, AI-powered notes, and more.
CONTINUE READING — FREEor get the app