Pollution

Air pollution worldwide is a growing threat to human health and the natural environment. It may be described as contamination of the atmosphere by gaseous, liquid, solid wastes, or by products that can endanger human health and welfare of plants and animals, attack materials, and reduce visibility. Although some pollutants are released by natural sources like volcanoes, coniferous forests, and hot springs, the effect of this pollution is very small when compared to that caused by emissions from industrial sources, power and heat generation, waste disposal, and the operation of internal com…