The environment comprises the natural components- air, water and land, the cities, factories, market places, automobiles etc. also come under the purview of the environment. They constitute the artificial environment. Air, water and land have some characteristic natural ingradients Air, for example contains 78% of Nitrogen, 21% of Oxygen, 0.03% Carbon Dioxide etc. Water is a compound of Hydrogen and Oxygen and it contains some chemical compounds and bacteria.
'Pollution' means the act of making dirty. Sometimes some extraneous harmful substances may somehow enter air, water and soil. Entry of such extraneous harmful substances hamper the natural properties of air, water and soil and make them unusable. Hampering natural properties of air, water and soil is called environmental pollution. The extraneous harmful substances that pollute the environment are called pollutants.
There are various kinds of pollutants. Some of them are gases, liquids or solids, radiations, stink and noise. Pollutants poison air and water and harm living beings.