Occupational Environmental Hazards

On this page

Occupational Hazards Intro - Workplace Perils Primer

  • Hazard Types:
    • Physical (noise, radiation)
    • Chemical (solvents, dusts)
    • Biological (bacteria, viruses)
    • Ergonomic (poor posture, repetitive tasks)
    • Psychosocial (stress, violence)
  • Routes of Entry: Inhalation (main), Ingestion, Skin absorption.
  • Core Concept: Dose-response relationship (↑dose = ↑effect).
  • Hierarchy of Controls (📌 ESEAP: Every Student Enjoys A Pizza): Ranked system for hazard control.
![Hierarchy of Controls for Occupational Hazards](https://ylbwdadhbcjolwylidja.supabase.co/storage/v1/object/public/notes/L1/Internal_Medicine_Environmental_Medicine_Occupational_Environmental_Hazards/df6a1443-6c9c-499d-b5ec-95b9101d57fe.jpeg)
> ⭐ The most effective level in the hierarchy of controls is **Elimination** of the hazard.

Pneumoconioses - Dust Devastation

Prolonged inhalation of specific occupational dusts leads to a group of irreversible, fibrotic lung diseases termed pneumoconioses. Key examples include:

DiseaseExposure SourceKey X-ray/Pathology FindingsComplications/Associations
SilicosisSand, quartz (mining, stone cutting)'Egg-shell' calcification (hilar nodes), Progressive Massive Fibrosis (PMF), upper lobe predominance↑TB risk
CWPCoal dustSimple: coal macules/nodules (upper lobes). Complicated: Progressive Massive Fibrosis (PMF).Caplan's syndrome (RA + pneumoconiotic nodules)
AsbestosisShipbuilding, insulation, constructionFerruginous bodies, pleural plaques (lower lobes, parietal), bibasilar fine end-inspiratory crackles. Fiber: $L >\textbf{5µm}$, $D <\textbf{3µm}$, $AR >\textbf{3:1}$↑Lung cancer (esp. smokers), Mesothelioma
BerylliosisAerospace, electronicsAcute chemical pneumonitis or chronic non-caseating granulomas (sarcoid-like, hilar lymphadenopathy)Chronic Beryllium Disease (CBD)
Formation of ferruginous bodies in asbestosis

Asbestos exposure is the single most important risk factor for malignant mesothelioma.

Toxic Agents - Metals & Cancer Culprits

Heavy Metals

MetalSourcesClinical FeaturesDiagnosticsChelators
LeadBattery, paint, smeltingBurton's line (gums), wrist/foot drop, abdominal colic, microcytic anemia (basophilic stippling), encephalopathy. 📌 LEAD: Lead lines, Encephalopathy, Anemia/Abdominal colic, Drop (wrist/foot). BLL >5 µg/dL (child), >10 µg/dL (adult)Blood Lead LevelCaNa2EDTA, DMSA, BAL
MercuryThermometers, batteries, dental amalgamTremor, erethism, gingivostomatitis, nephrotic syndrome. Minamata disease (organic Hg)Urine/blood mercuryDMSA, BAL
ArsenicPesticides, semiconductors, wood preservativeGarlic breath, Mees' lines, skin hyperkeratosis/pigmentation, peripheral neuropathy, cancers (lung, skin, bladder)Urine arsenic, Mees' lines on nailsBAL, DMSA

Occupational Cancers

  • Lung: Asbestos, Radon, Arsenic, Chromium, Nickel, Polycyclic Aromatic Hydrocarbons (PAHs).
  • Bladder: Aromatic amines (e.g., Benzidine, 2-Naphthylamine - dye/rubber industry).
  • Leukemia (AML): Benzene.

    Benzene exposure is a well-established cause of Acute Myeloid Leukemia (AML).

  • Angiosarcoma (liver): Vinyl chloride (plastics industry).
  • Skin: PAHs, Arsenic, UV radiation.

Other Hazards - Asthma to ZZZ-Be-Gone (Noise)

  • OA: Most common. Sensitizer (latency, prior exposure) vs. Irritant (no latency, high exposure).

    • Agents: Isocyanates, flour, wood dust, dander.
    • Dx: PFTs, IgE, PEFR (work/home).
  • Dermatitis: ICD vs. ACD.

    • Agents: Solvents, nickel, wet work.
    • Dx: Patch test (ACD).
  • NIHL: Sensorineural, bilateral. Notch: 4000 Hz.

    ⭐ The hallmark of Noise-Induced Hearing Loss on an audiogram is a characteristic notch (dip in hearing threshold) at 4000 Hz.

    • OSHA: 85 dBA TWA. Prevention key.
    • Audiogram showing 4kHz notch in NIHL
  • Pesticide Poisoning:

    • Organophosphates (OPs): Cholinesterase inhibitors. 📌 SLUDGE/DUMBELS mnemonic for muscarinic effects: Salivation, Lacrimation, Urination, Defecation, GI upset, Emesis / Diarrhea, Urination, Miosis, Bronchospasm, Emesis, Lacrimation, Salivation. Rx: Atropine + Pralidoxime.
    • Carbamates: Like OPs, reversible. Pralidoxime not usually needed.
    • Organochlorines (DDT): CNS stimulation.

High‑Yield Points - ⚡ Biggest Takeaways

  • Silicosis: Eggshell calcification, ↑ TB risk. Asbestosis: Lower lobes, pleural plaques, mesothelioma.
  • Lead poisoning: Basophilic stippling, wrist drop. Arsenic: Aldrich-Mees lines, skin cancer.
  • BenzeneLeukemia. Vinyl chlorideHepatic angiosarcoma. Aromatic aminesBladder cancer.
  • Byssinosis: "Monday fever" in cotton workers.
  • Noise-Induced Hearing Loss: Notch at 4000 Hz.
  • Bagassosis: Hypersensitivity pneumonitis from moldy sugarcane.
  • Irritant contact dermatitis: Most common occupational dermatitis.

Practice Questions: Occupational Environmental Hazards

Test your understanding with these related questions

A 3 yrs old child is brought to the emergency room by his parents after they found him having a generalized seizure at home. The child's breath smells of garlic, and he has bloody diarrhea, vomiting, and muscle twitching. Which poison is it likely that this child has encountered?

1 of 5

Flashcards: Occupational Environmental Hazards

1/8

_____ syndrome is a combination of rheumatoid arthritis and pneumoconiosis with intrapulmonary nodules

TAP TO REVEAL ANSWER

_____ syndrome is a combination of rheumatoid arthritis and pneumoconiosis with intrapulmonary nodules

Caplan

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

Start Your Free Trial