6. Natural Resources
An undesirable change in the physical, chemical or biological characteristics of the air making it harmful for the living organisms (including man) is termed air pollution. Common pollutants of air are particulate matter and gaseous pollutants. Particulate matter is also called suspended particulate matter (SPM) because it remains suspended in air for a reasonable period of time. Common examples of SPM are dust, soot (unburnt, carbon, particles), smoke, flyash etc. Gaseous pollutants include carbon monoxide, excess of carbon dioxide, sulphur dioxide, oxides of nitrogen, hydrocarbons, chlorofluorocarbons (CFCs), hydrogen sulphide, methane and ammonia. Besides, asbestos dust, stone dust, cement dust, pollen grains of plants, radioactive rays etc. are other common air pollutants.
Sources of Air Pollution :
Some common harmful effects of air pollution are -
Respiratory problems, e.g., sneezing, allergy, bronchitis, asthma,, tuberculosis and lung cancer.
Carbon monoxide poisoning.
Depletion of ozone layer.
Global warming (green hourse effect).
Serious ailments produced by certain metals and pesticides.