Question

What are the sources of water pollution?

Answer 1

1. Oil spills:
   Crude oil and refined form enter water bodies during transport of oil, accidental spillages, harbours, coastal industries etc .This is harmful to planktons, fishes and marine plants.
2. Toxic metals:
    Industrial effluents carry heavy metals like mercury, copper, zinc. lead etc.
3. Agricultural waste:
   Excess of fertilizers enter into water bodies. Various pesticides, herbicides etc. enter water bodies along with runoff from agricultural fields.
4. Acids and Alkalies:
   Various manufacturing units and chemical industries and mining operations are responsible for release of acids and alkalies to water bodies.
5. Soaps and Detergents:
   Waste water from laundry, textile mills and domestic sewage contain large amount of soaps and detergents. They also contain non- degradable pollutants like benzene sulphonates.
6. Gases:
   Ammonia, Chlorine, Hydrogen sulphide, Ozone, etc. are the main gaseous pollutants.
7. Radio- active wastes:
   These include harmful radiations from nuclear power stations, drainage from hospitals, industries and nuclear research stations.
8. Heated effluents (Thermal Pollution):
   Large amount of heated water are released from power stations and various industries and nuclear research stations.
9. Pathogens:
   From slaughter houses, tanning industries waste water from municipalities may also contain many pathogenic micro-organisms like bacteria, fungi, etc.
10. Sewage disposal:
    Domestic sewage contains urine, faeces, soaps, detergents, food remains and several other substances along with waste water.
11. Acid rains:
    It may be secondary effect of air pollution, which alters pH of water bodies.