Question

Write the pollutants, harmful effects and control of water pollution.

Answer 1

Many undesirable and harmful inorganic, organic or biological elements pollute the water. Such pollutants harm the life as most of the part of protoplasm is made up of water.

The problem of getting fresh drinking water is increasing all over the world. The pure drinking water should be neat, tasteless, colorless, having pH value 7 to 8.5 and dissolved salts within permitted limit.

Sources and type of water pollution :
There are many sources and factors which cause water pollution. They may be natural or human caused sources. The natural sources are difficult to control but human caused sources can be controlled. The human caused water pollutants are sewage, domestic wastes, industrial and agricultural wastes etc. Some of them are as follows –

1. Sewage and Domestic Waste :
They are the big threat to water pollution and it is increasing with increasing urbanization. They are released directly into rivers, ponds, lakes etc. Hence, their water get polluted. The sewage includes city garbage and human excreta etc. The sewage decrease O₂ in the water which is lethal for aquatic life.

2. Industrial waste :
The industrialization is increasing along with the increase in human population. The industrialization is another big factor of water pollution. Many industries such as plastic, rubber, paper, soap, chemicals etc. release many harmful substances in the water. Some heavy metal (cadium, mercury) pollution develop diseases.

3. Pesticides :
Pesticides are used to protect the crop from harmful insects. These pesticide ultimately reach into the water bodies along with rain water. These chemicals of pesticides are determined to health.

4. Chemical fertilizers :
Chemical fertilizers are used to provide nutrients to the crop. They contain various types of chemicals which impose harmful effects on the animals and human beings.

5. Thermal Pollution :
The temperature of water bodies such as oceans, ponds etc. is increasing because of many industries, atomic blasts etc. This high temperature is harmful for the aquatic life such as fishes, algae etc.

6. Oil Pollution :
Crude oil (mineral oil) is transported using big ships through ocean routes. The spilling of this oil makes thick covering on the water. As a result the aquatic animals die of asphyxia.

Harmful effects of Water Pollution :
Water pollution causes many types of detrimental effects such as –

1. Sewage polluted water may cause typhoid, diarrhea, Jaundice, Cholera etc.
2. Contact of soil containing human excreta may cause in-fection of many types of worms such as hook worm, Ascaris etc.
3. Bathing in polluted water may cause weil’s disease, schistosomiasis and other skin diseases.
4. Drinking of polluted water having DDT, BHC etc. may casue abortion and embroyonie abnormalities. There is biomagnification of non-biodegradable pollutants i.e. there concentration increases in higher tropic levels.
5. Industrial waste may cause diseases related to liver, kidney, brain etc.
6. The polluted water also cause following diseases –

• Mercury pollution causes minamata disease. It is a disease of nervous system. It causes numbness in feet, lips, tongue etc. paralysis in children and epilepsy.
• Lead pollution causes diseases related to muscles and central nervous system.
• Flouride pollution in water results in diseases called flourosis. It effects the teeth and bones. The legs bend outwards which is called as Knock Knee Syndrome.
• Cadium pollution in water causes itai-itai or ouch-ouch disease.

Control of Water Pollution :

1. Ecological stabilization is the most effective way to control water pollution.
2. To make the public aware using movies, symposiums regarding ill effects of water pollution.
3. Reuse of the wastes after recycling.
4. Treatment of drinking water to make it suitable.
5. Time to time quality checking of water bodies.