Question

Write the four causes of water pollution and explain the control of water pollution.

Answer 1

Hint: To answer this question, you must recall the sources of water pollution and the ways by which it can be reduced. Water pollution in simple words refers to the occurrence of any physical, chemical or biological change in the water present in water bodies.

Complete step by step solution
The major causes of water pollution are:
Sewage: It consists mainly of organic matter, human excreta, household wastes, detergents, soaps, etc. Water pollution occurs when sewage is allowed to run into the water bodies. These pollutants are decomposed by the bacteria present in them as well as those in the water, making the water unfit for domestic use.
Industrial effluents: Discharges from various factories and industries consist of both organic and inorganic pollutants like grease, oil, metallic wastes, plastics, various suspended solids etc. Most of these pollutants are non- decomposable and create serious threats.
Agricultural discharges: Agricultural practices nowadays, involve the use of many types of chemical fertilizers, pesticides, insecticides, etc. These chemicals often run off into neighboring water bodies causing water pollution.
Radioactive wastes: Radioactive waste products formed in nuclear reactors if dumped carelessly into water bodies results into water pollution.
Control of water pollution:
All domestic and industrial waste material must be treated properly before they are discharged into the water bodies. The industrial effluents should be treated more extensively as they may contain highly harmful chemical pollutants. The best method for preventing and controlling water pollution is recycling of the waste products and pollutants.

Note
Water pollution involves the contamination of water by toxic substances that are not otherwise present in it naturally. Thus, it affects the body functioning and health of aquatic plants and animals greatly.