Air Polution

Wherever you go, whatever you do inside, outside, on top of mountain, deep in a coalmine you are always surrounded by a sea of gases. This sea is called the air, or the atmosphere.
The gases of the atmosphere cannot be seen, and we are rarely aware of them. But they are of the greates importance. Without the atmosphere, people, animals, an plat could not live. Of almost equal importance is the quality of the atmosphere whether it is pure or polluted (meaning impure).

The atmosphere is made up mainly of the gases oxygen and nitrogen, together with water vapor and smaller amounts of carbon dioxide and other gases. But all air contains small amounts of impurities. In rural areas, far removed from factories and heavy traffic, the air my countain pollen from plants, dust from the soil, and even bacteris. These impurities are usually is such small amounts that they are not important.
Air is said to be polluted when it contains enough harmful impurities to effect the helath, safety, or comfort of living things. The impurities, or pollutans, could be tiny particle of matter or gases not normaly found in air.

When people breathe, pollutans in the air may be deposited in the lungs or absorbed into the body. And polluted air can harm animals and plants as well as people. For this reason, our air supply should be closely watched and managed to assure its good quality.