Human impact, pollution and waste
Human activity pollutes air, water, soil and sound and generates many kinds of waste. India controls pollution through Acts and waste through rules, mostly of 2016.
Human activities and their footprint
- Agriculture: fertiliser and pesticide run-off, soil degradation, groundwater depletion.
- Industry and power: smoke, effluents, hazardous waste.
- Mining and deforestation: habitat loss, erosion, siltation of rivers.
- Urbanisation and transport: vehicle exhaust, sewage, solid waste, noise.
- Scale of issues: local (garbage, noise), regional (acid rain, river pollution, smog), global (climate change, ozone depletion).
Types of pollution
| Type | Main sources | Key measure and law |
|---|---|---|
| Air | Vehicles, power plants, industry, crop-residue burning, dust | Air Quality Index; Air Act 1981 |
| Water | Sewage, industrial effluent, farm run-off | BOD and dissolved oxygen; Water Act 1974 |
| Soil | Pesticides, excess fertiliser, heavy metals, plastics, landfill leachate | Covered by the Environment (Protection) Act 1986 |
| Noise | Traffic, industry, loudspeakers, construction | Decibels, dB(A); Noise Pollution (Regulation and Control) Rules 2000 |
Types of waste and the rules that govern them
| Waste | Examples | Indian rules |
|---|---|---|
| Solid (municipal) | Household, market and street waste | Solid Waste Management Rules 2026 (replaced the 2016 Rules; segregation at source into wet, dry, sanitary and special-care waste) |
| Liquid | Sewage, industrial effluent | Water Act 1974; treated in sewage and effluent treatment plants |
| Biomedical | Dressings, sharps, body parts, expired drugs | Bio-Medical Waste Management Rules 2016 |
| Hazardous | Toxic, corrosive, flammable or reactive industrial waste | Hazardous and Other Wastes Rules 2016 |
| Electronic | Discarded phones and computers (lead, mercury, cadmium) | E-Waste (Management) Rules 2022, with extended producer responsibility |
| Plastic | Bags, packaging, single-use items | Plastic Waste Management Rules 2016 |
Biomedical waste: colour-coded segregation
| Colour | What goes in |
|---|---|
| Yellow | Anatomical waste, soiled dressings, expired or discarded medicines, chemical waste (mostly incinerated) |
| Red | Contaminated recyclable items: tubing, bottles, catheters, gloves |
| White (translucent, puncture-proof) | Sharps: needles, blades, scalpels |
| Blue | Glassware and metallic body implants |
How NET asks this: match a waste type with its rules or bin colour, pick the pollutant behind an effect, or classify an issue as local, regional or global.
Typical MCQ: “Which colour bag holds anatomical waste under the Bio-Medical Waste Management Rules 2016?” Yellow; this waste is mostly incinerated.
Typical MCQ: “What does a high BOD value in a river indicate?” Heavy organic pollution: microbes use up much oxygen breaking it down, leaving less for fish.
Bin colours: yellow burns (body parts, soiled dressings, expired drugs), red recycles (tubing, bottles, gloves), white takes sharps, blue takes glass.