Pollution Caused by Man

1. Automobiles: The numbers of vehicles are increasing rapidly in our cities. The exhaust emission from vehicles contain poisonous substances like sulphur dioxide, carbon monoxide, lead, nitrogen oxides, particulate matter and smoke which cause air pollution on entering in the environment.

2. Domestic activities: When wood, cow dung cakes, coal and kerosene are burnt to cook food, these generate thick smoke which pollute the air. This smoke contains sulphur dioxide, carbon monoxide and unburnt carbon compounds.

3. Industries: Many of the industries like chemical plants, steel, fertilizers, sugar and cement manufacturing units emit large amount of smoke and pollutants like oxides of sulphur and nitrogen, lead particles and chlorofluorocarbons (CFCs) which pollute the air. For example, the emissions from the oil refinery at Mathura and the numerous coal burning industries at Agra contain sulphur dioxide which causes acid rain. Many industries produce chemicals, some of which escape into the atmosphere causing air pollution.

4. Agricultural activities: Excessive use of fertilizers and pesticides in agriculture pollutes the air. Pesticides are those chemical compounds which are used for killing pests that destroy agricultural production or in some way are harmful to humans.

5. Burning of refuse: Due to the burning of refuse, a lot of smoke and ash is produced into the atmosphere. Air is polluted by the presence of gases like sulphur dioxide, carbon dioxide and oxides of nitrogen.

6. Thermal power plants: In thermal power plants huge amount of coal is burnt to produce electricity. Thus, smoke and fly ash is released into the atmosphere. Fly ash consists of minute particles of silica, alumina, lead, arsenic, etc. It can cause irritation and respiratory disorders.

7. Nuclear power plants: They pollute air by releasing radioactive rays.

8. Deforestation: Indiscriminate cutting of trees and clearing of forests increase the amount of carbon dioxide in the atmosphere and thereby pollutes it.

9. Use of chlorofluorocarbons : In refrigeration, fire extinguishers and aerosol sprayers pollute air by depleting the ozone layer.

10. Smoke: Smoke is generated from the exhaust of vehicles like bus, car, autorickshaw, or a scooter. It also comes out from a factory chimney. Speeding cars and trucks cause dust to rise from the roads. Fly ash is generated by the thermal power plants. Cigarette smokers also add to air pollution. They not only harm themselves, but also harm people around them who are forced to inhale the cigarette smoke.

11. Stone dust: Fine dust of stone particles is produced when stones are dug out from beneath and cut, polished or crushed. This stone dust enters into the air. When the air is inhaled the damages the respiratory organs. It can cause many serious disorders like cancer, etc.

Sample Questions

(More Questions for each concept available in Login)

Question : 1

Depletion of water table is due to ____________________
A. Scanty rainfall	B. Increase in activites	C. Industrial activites	D. All of the above
Right Option : D
View Explanation

Question : 2

Which of following is a cause of air pollution?
A. Rheumatism	B. Bronchitis	C. Neural problems	D. Thyroid
Right Option : B
View Explanation

Question : 3

_____________________ is the main reason for decrease in species diversity in tropical countries.
A. Afforestation	B. Deforestation	C. Over grazing	D. Soil erosion
Right Option : B
View Explanation