What are the major causes of water pollution? Explain.
Several human activities leads to presence of several undesirable substances in water which causes water pollution. Various sources of different water pollutants are shown below.
Pollutant | Source |
Micro-organisms | Domestic sewage
|
Organic wastes
| Domestic sewage, decaying animals and plants, animal excreta and waste, discharge from food processing industries.
|
Plant nutrients
| Chemical fertilizers
|
Toxic heavy metals
| Chemical factories and industries
|
Sediments | Strip mining and soil erosion
|
Pesticides | Chemical used for killing fungi, weed, insects
|
Radioactive substances
| Mining of uranium-containing minerals
|
Heat | Water used for cooling in industries. |