Occupational Health Risks

Why This Matters

Occupational health is where public health meets the everyday reality of work—and it's a cornerstone of the field. You're being tested on your ability to recognize how workplace environments create distinct health risks and what systems exist to prevent harm. The concepts here connect directly to broader public health principles: exposure pathways, dose-response relationships, primary prevention, and regulatory frameworks. Understanding occupational health means understanding how social determinants (like job type and industry) directly shape health outcomes.

This isn't just about memorizing a list of hazards. Exam questions will ask you to identify which type of hazard applies to a scenario, explain the mechanism of disease, or evaluate the effectiveness of interventions. Don't just know what the hazards are—know why they cause harm and how we prevent it. That's the difference between recognizing "chemical hazard" and being able to explain why a welder develops respiratory disease twenty years into their career.

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Environmental Exposure Hazards

These hazards involve direct contact with harmful agents in the physical environment. The key mechanism is dose-response: the amount and duration of exposure determine the severity of health effects.

Physical Hazards

• Noise-induced hearing loss—occurs when prolonged exposure to sounds above 85 decibels damages cochlear hair cells, making this one of the most common occupational injuries worldwide
• Ionizing radiation causes cellular DNA damage and increases cancer risk; workers in healthcare (radiology), nuclear energy, and certain manufacturing face elevated exposure
• Thermal stress ranges from heat stroke in outdoor laborers to hypothermia in cold storage workers—both disrupt the body's thermoregulation and can be fatal

Chemical Hazards

• Toxic substance exposure follows predictable pathways—inhalation, ingestion, or dermal absorption—and can cause acute poisoning or chronic conditions like occupational asthma
• Industrial fumes from welding, painting, and solvent use irritate respiratory mucosa and can lead to occupational COPD or metal fume fever
• Particulate matter (dust) deposits in lung tissue; construction and mining workers face high rates of pneumoconiosis, a preventable but irreversible lung disease

Biological Hazards

• Infectious agents spread through occupational contact—healthcare workers face bloodborne pathogens (HIV, Hepatitis B/C), while agricultural workers encounter zoonotic diseases
• Workplace allergens including mold spores, animal dander, and latex proteins trigger IgE-mediated responses ranging from rhinitis to anaphylaxis
• High-risk industries include healthcare, agriculture, veterinary medicine, and laboratory work—understanding industry-specific risks is essential for targeted prevention

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Workplace Design and Behavioral Hazards

These hazards emerge from how work is organized and performed rather than from external agents. Prevention focuses on redesigning work processes and environments.

Ergonomic Hazards

• Repetitive strain injuries like carpal tunnel syndrome and tendonitis develop when the same motions stress tendons and nerves over months or years—common in assembly line and computer work
• Postural strain from prolonged sitting, standing, or improper lifting mechanics causes chronic musculoskeletal disorders, particularly low back pain
• Ergonomic interventions—workstation redesign, job rotation, and proper lifting training—represent primary prevention by eliminating the hazard at its source

Psychosocial Hazards

• Chronic occupational stress activates sustained cortisol release, contributing to cardiovascular disease, depression, anxiety, and immunosuppression
• Workplace violence encompasses bullying, harassment, and physical assault—healthcare and social service workers face the highest rates
• Organizational factors like job insecurity, lack of autonomy, and poor management are modifiable risk factors; supportive workplace policies are a form of structural intervention

Safety Hazards

• Falls are the leading cause of workplace fatalities in construction; risk increases with height, inadequate fall protection, and surface conditions
• Machinery accidents result from inadequate guarding, improper lockout/tagout procedures, and insufficient training—most are preventable through engineering controls
• Hierarchy of controls prioritizes elimination and engineering solutions over PPE and administrative measures for maximum effectiveness

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Disease Outcomes and Long-Latency Conditions

Some occupational exposures cause diseases that appear years or decades after initial contact. Understanding latency periods is critical for connecting exposure history to diagnosis.

Occupational Lung Diseases

• Asbestosis develops from inhaled asbestos fibers that cause progressive pulmonary fibrosis; latency period is typically 10-40 years after first exposure
• Silicosis results from crystalline silica dust (sandblasting, mining, stonecutting) causing nodular lung fibrosis—it's irreversible but entirely preventable
• Mesothelioma is a fatal cancer of the pleural lining almost exclusively caused by asbestos; even brief exposures decades earlier can be responsible

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Prevention and Regulatory Frameworks

Public health approaches to occupational hazards emphasize prevention through regulation, engineering controls, and systematic monitoring. These represent the field's primary tools for protecting worker health.

Personal Protective Equipment (PPE)

• PPE categories include respiratory protection (N95s, respirators), eye/face protection, hearing protection, and dermal barriers—each matched to specific hazard types
• Hierarchy of controls places PPE as the last line of defense; it's less effective than eliminating hazards or implementing engineering controls
• Employer responsibility includes hazard assessment, PPE provision, fit testing, and training—workers cannot be charged for required safety equipment

Occupational Exposure Limits

• OELs are regulatory thresholds (measured in ppm or $mg/m^3$) representing the maximum allowable concentration of a substance over a work shift
• Permissible Exposure Limits (PELs) are legally enforceable OSHA standards, while Threshold Limit Values (TLVs) are recommended guidelines from ACGIH
• Industrial hygiene monitoring through air sampling and biological monitoring ensures compliance and identifies exposure risks before disease develops

Workplace Safety Regulations

• OSHA (Occupational Safety and Health Administration) sets and enforces federal workplace safety standards; violations carry significant penalties
• NIOSH (National Institute for Occupational Safety and Health) conducts research and makes recommendations but doesn't have enforcement authority—know the difference
• Workers' compensation systems provide no-fault insurance for occupational injuries and diseases, creating economic incentives for employer compliance

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Quick Reference Table

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Self-Check Questions

1. A construction worker develops progressive shortness of breath 25 years after working with insulation materials. Which occupational diseases should be considered, and what connects them mechanistically?

2. Compare and contrast how you would approach preventing chemical hazards versus ergonomic hazards in a manufacturing facility. Which level of the hierarchy of controls applies to each?

3. Which two types of occupational hazards are most relevant to healthcare workers, and what specific exposures within each category pose the greatest risk?

4. An FRQ asks you to evaluate a workplace intervention program. What's the difference between providing PPE to workers and installing ventilation systems, in terms of the hierarchy of controls?

5. OSHA and NIOSH both focus on occupational health. If a question asks which agency would conduct a health hazard evaluation at a workplace versus which would issue a citation for violations, how would you answer?