Water pollution occurs when undesirable and unwanted substances are added to the water bodies thus choking the aquatic life in those water bodies.
The major sources of water pollutants are as given below:
Domestic sewage, discharge from food
processing industries, animal
excreta and waste, decaying animals and plants
|Sediments||Strip mining and soil erosion|
|Plant nutrients||Chemical fertilizers|
|Radioactive substances||Mining of uranium ores|
|Pesticides||Chemicals used for killing fungi, weed, insects|
|Toxic heavy metals||Chemical factories and industries|
|Heat||Water used for cooling in industries|
The major pollutants are:
1. Pathogens: Bacteria and other micro-organisms come under this category. They get into water bodies through domestic sewage and animal excreta. Bacteria like Escherichia coli and Streptococcus faecalis which are found in human excreta are known vectors of gastrointestinal diseases.
2. Organic wastes: They are generally bio-degradable wastes that pollute the water bodies by mixing with them during their runoff phase. An excess amount of organic matter in water bodies suck up the dissolved oxygen in water thus inhibiting aquatic life in these water bodies.
3. Chemical pollutants: Heavy metals like mercury, cadmium and nickel come under this category. These chemicals when present above the allowable limit can result in damage of the central nervous system, kidneys and liver.Answered by Pragya Singh | 1 year ago