Administrative: Restrict loudspeakers, zoning, limit night industrial operations
Environmental: Tree plantation, green belts
Personal Protective: Ear plugs, ear muffs
Legislative: Enforce noise control laws, monitor permissible levels
Public Awareness: Education on harmful effects of noise
2(a) Define BOD
BOD (Biochemical Oxygen Demand): Amount of dissolved oxygen required by microorganisms to decompose organic matter in water under aerobic conditions over 5 days at 20°C. Importance: Indicates organic pollution – higher BOD = higher pollution level.
2(b)(i) Presumptive coliform count
Principle: Coliform bacteria ferment lactose producing acid and gas. Method: Water sample in lactose broth, incubation, gas formation indicates presumptive coliforms. Importance: Indicates faecal contamination, helps assess drinking water safety. Result: Expressed as MPN (Most Probable Number) per 100 ml.
2(b)(ii) Reverse Osmosis
Principle: Water forced through semipermeable membrane under pressure opposite to natural osmosis. Uses: Removal of dissolved salts, arsenic, fluoride; drinking water purification. Advantages: Effective purification, removes microorganisms/chemicals. Disadvantages: Expensive, water wastage, maintenance required.
Definition: Collection and storage of rainwater for future use. Objectives: Water conservation, groundwater recharge, reduce water scarcity. Methods: Rooftop harvesting, surface runoff harvesting, recharge pits/wells. Advantages: Increases groundwater level, reduces flooding, provides water during drought. Limitations: Initial cost, maintenance required.
4(c) Bio-pesticides
Definition: Pesticides derived from natural organisms (bacteria, fungi, plants, animals). Types: Microbial, plant-incorporated protectants, biochemical. Examples:Bacillus thuringiensis (Bt), neem products. Advantages: Eco-friendly, biodegradable, less toxic to humans. Disadvantages: Slow action, short shelf life. Uses: Organic farming, integrated pest management.
4(d) Incineration
Definition: Controlled burning of waste at high temperature to reduce volume and destroy pathogens. Types: Municipal waste incineration, biomedical waste incineration. Advantages: Reduces waste volume, destroys infectious organisms, generates energy. Disadvantages: Air pollution, expensive installation, toxic ash production. Precautions: Proper emission control, segregation of waste before burning.
📌 Key Takeaways: This paper covers essential environmental health topics – flood disaster preparedness, sick building syndrome, water quality indicators (BOD, coliform), water purification (RO), radiation protection, occupational health (beedi workers), global warming mitigation, heavy metal toxicity (mercury), rainwater harvesting, bio-pesticides, and waste management (incineration).