With the rapid increase in the human population and industrial revolution, the demands for the natural raw materials and the sources of energy are increasing day by day.

This is increasing the pollution of air, water and soil to the larger extent. Most of the air pollution is due to the products of combustion of various types of fuels. The gases and fumes emitted by the factories and vehicles like cars, busses and trucks which pollute the air. Pollutant such as carbon mono-oxide, CO; carbon dioxide, CO2; hydrogen Sulphide, H2S, sulphur dioxide, SO2; and sculpture trioxide, SO3; are noxious gasses which pollute the air in and around the city. Carbon monoxide is a poisonous gas which leads to preparatory problems, carbon dioxide enhances the green house effect leading to excessive heating of the earth and its atmosphere, hydrogen sulphide is a poisonous gas which tarnishes silver objects and blackens lead paints, sulphur dioxide and sulphur trioxide produce acid rain and damage crop plants and buildings made of marble.

The water pollution is caused by polluting the water by dumping industrial waste and chemicals and also by dumping the sewage. Some of the chemical fertilizers and pesticides which are applied to crop plants are washed into the water bodies like pools, lakes and rivers and pollute the water. This polluted water harms the aquatic life like fish as well as the man. When the excess of nitrate fertilizer is put in the soil of the field, some of them reach the pond thru the rain water. Water polluted by nitrate is not fit for drinking by human beings. Nitrates in the water promote the growth of vegetation of algae in the water, which deoxygenate water. Due to this some aquatic animals may also die. Since the fishes start to die less sea food is available to the human beings.
Talking about the soil pollution, one of the most important sources which pollute the soil is due to acid rain. The various chemical industries emit sulphur dioxide into the air along with some sulphur trioxide. The vehicles like car, busses etc, which run on internal combustion engines, also emit some sulphur dioxide gas in to the atmosphere, thus causing acid rains. The presence of acid in the soil becomes toxic for the plant growth. The acid rain also damages the standing crops.

Ozone layer is very important for the existence of life on earth. The ozone layer absorbs most of the harmful and strong ultra violate radiations emitted by the sun, which can other wise cause skin cancer. It has now been found that the amount of ozone is being depleted, due to which the ozone layer in the upper atmosphere is becoming thinner and thinner day by day. The depletion of ozone layer is due to the use of chemical called aerosols sprays, propellants like floro-carbons and choloro-floro-carbons. If the ozone layer in the atmosphere get completely depleted, then all the harmful ultra violet rays coming from the sun would reach the earth can cause many problems. It would melt the polar ice caps and this would rise the water levels thus causing global warming. Thus the world should be saved from all the types of pollutions.