Environmental Health

MPH 1st Semester – WBUHS (June–July 2023) | Detailed Questions & Answers

1(a) Occupational Health Hazards of Road Builders

🏗️ Physical Hazards

Noise: Hearing loss, stress, hypertension
Heat: Heat exhaustion, stroke, dehydration
Vibration: Joint pain, hand-arm vibration syndrome

💨 Dust Hazards (Silica)

Silicosis, chronic bronchitis, asthma, TB

🧪 Chemical Hazards

Bitumen fumes, diesel exhaust → skin/eye irritation, respiratory diseases, carcinogenic risk

⚙️ Mechanical Hazards

Fractures, crush injuries, disability, death

🦺 Ergonomic Hazards

Backache, muscle strain, joint disorders

🦟 Biological Hazards

Malaria, dengue, diarrheal diseases

🛡️ Preventive Measures

Engineering: Dust suppression (water spraying), noise control, machine guarding
PPE: Helmet, gloves, ear plugs, masks, safety boots
Administrative: Health education, rotational duty, rest & hydration
Medical: Periodic check-ups, vaccination, first aid services

1(b) "E-Waste – A Public Health Priority of Today" – Justify

Definition: Discarded electrical/electronic devices (computers, phones, TVs, batteries, refrigerators).

Why increasing: Rapid tech advancement, consumerism, short product lifespan.

⚠️ Toxic Components

Lead, Mercury, Cadmium, Chromium, Brominated flame retardants

🏥 Health Hazards

Neurological: Memory loss, developmental delay in children
Respiratory: Asthma, bronchitis
Skin: Dermatitis
Kidney/Liver damage
Cancer risk

🌍 Environmental Hazards

Air pollution (open burning)
Soil & water contamination (heavy metals)

✅ Why Public Health Priority

Large volume of e-waste
Informal recycling sector exposure
Harm to children and workers
Long-term toxic effects

Control Measures: Proper recycling, Extended Producer Responsibility (EPR), public awareness, government regulation, Reduce-Reuse-Recycle.

2(a) Swimming Pool Sanitation

Definition: Maintaining hygienic and safe water conditions in swimming pools.

Key Measures

Filtration: Sand/pressure filter removes suspended impurities
Disinfection (Chlorination): Residual chlorine 0.5 mg/L kills bacteria/viruses
pH Maintenance: 7.2–7.8 prevents eye irritation, improves chlorine efficiency
Regular cleaning of pool floor & debris removal
Water circulation prevents stagnation
Health education: Shower before entry, no spitting/urinating

Diseases prevented: Conjunctivitis, skin infection, GI infection, ear infection.

2(b) Activated Sludge Process

Definition: Biological sewage treatment using aerobic microorganisms.

Steps

Primary Treatment: Removal of large suspended particles
Aeration Tank: Sewage + activated sludge + air → bacterial growth
Formation of Flocs: Bacteria clumps digest organic matter
Sedimentation Tank: Flocs settle, clear water separated
Recycling of Sludge: Part returned to aeration tank, rest disposed

Advantages: Efficient treatment, reduces BOD, less odor.
Disadvantages: Expensive, requires electricity, skilled supervision.

2(c) Swachh Vidyalaya Abhiyan

Definition: National school sanitation initiative.

Components

School toilets (separate for boys & girls)
Hand washing facilities (soap & water)
Safe drinking water
Hygiene education (handwashing, menstrual hygiene, cleanliness)
Waste management

Importance: Reduces absenteeism, prevents disease, improves girl child education, promotes healthy behavior.

2(d) Skin Manifestation of Arsenic Poisoning (Arsenicosis)

Manifestation	Description
Melanosis	Diffuse dark pigmentation (chest, back, limbs); "rain drop" pattern
Keratosis	Thickening of palms and soles
Hyperkeratosis	Hard nodules, rough skin lesions
Leucomelanosis	Mixed hypo- and hyperpigmented lesions
Skin Cancer	Squamous cell carcinoma, basal cell carcinoma (long-term exposure)

Other features: Weakness, neuropathy, GI symptoms.
Prevention: Safe drinking water, arsenic removal plants, health screening.

3(a) Five Major Indoor Air Pollutants, Sources & Health Hazards

Pollutant	Sources	Health Hazards
Carbon monoxide (CO)	Incomplete combustion, biomass fuel	Headache, dizziness, death
Particulate matter (PM2.5/PM10)	Smoke, cooking fuel, tobacco	Asthma, COPD, lung disease
Sulfur dioxide (SO₂)	Coal burning, kerosene	Respiratory irritation
Nitrogen dioxide (NO₂)	Gas stoves, fuel burning	Bronchitis, asthma
Formaldehyde	Paints, furniture, adhesives	Eye irritation, cancer risk

Other pollutants: Tobacco smoke, radon, mold spores, VOCs.
Prevention: Proper ventilation, clean fuel, smoke-free homes, chimneys/exhaust.

3(b) Why Under-Five Children are More Vulnerable to Lead Poisoning? Diagnosis

👶 Reasons for Vulnerability

Increased absorption than adults
Developing nervous system
Hand-to-mouth behavior
Poor nutrition (iron/calcium deficiency increases absorption)
Smaller body size → severe toxicity with small amounts

📌 Sources

Lead paint, contaminated water, batteries, industrial pollution, toys/cosmetics

🩺 Diagnosis

Blood Lead Level (BLL): ≥3.5 µg/dL elevated (CDC reference)
Clinical examination: Pallor, irritability, developmental delay
Lab tests: Hemoglobin, peripheral smear
X-ray: Lead lines in growing bones
Environmental history of exposure sources

Health effects: Reduced IQ, learning disability, behavioral problems, anemia, abdominal pain, convulsions, encephalopathy.
Prevention: Remove lead sources, improve nutrition, public awareness, screening.

4. Types of Man-Made Disaster and Their Prevention

Definition: Disasters caused by human activities, negligence or technological failure.

⚠️ Types

Industrial: Gas leakage, chemical explosion (Bhopal Gas Tragedy)
Nuclear: Radiation leakage → cancer, genetic mutation
Fire: Factories, buildings, markets (electrical short circuit, carelessness)
Transport accidents: Road, rail, air, ship
Biological: Bioterrorism, lab accidents
Environmental pollution: Oil spills, toxic waste, air pollution episodes
Terrorism & war: Bomb blasts, armed conflicts

🛡️ Prevention

Strict enforcement of industrial safety & environmental laws
Safety training & disaster preparedness drills
Early warning systems (gas leak alarms, fire alarms, radiation monitoring)
Regular inspection of machinery, electrical systems, chemical storage
Use of PPE (helmet, gloves, masks)
Emergency preparedness plan (evacuation, mock drills, first aid)
Public awareness & community education
Intersectoral coordination (health, fire, police, administration, NGOs)

📌 Conclusion: Environmental health focuses on prevention of disease and promotion of safe surroundings. Proper sanitation, pollution control, occupational safety and disaster preparedness are essential for protecting community health.