Air Pollution, contamination of the atmosphere by gaseous, liquid, or solid wastes or by-products that can endanger human health and the health and welfare of plants and animals, or can attack materials, reduce visibility, or produce undesirable odors. Among air pollutants emitted by natural sources, only the radioactive gas radon is recognized as a major health threat. A byproduct of the radioactive decay of uranium minerals in certain kinds of rock, radon seeps into the …showed first 75 words of 544 total…

…showed last 75 words of 544 total…elderly, smokers, workers whose jobs expose them to toxic materials, and persons with heart or lung disease. Other adverse effects of air pollution are potential injury to livestock and crops. Often, the first noticeable effects of pollution are aesthetic and may not necessarily be dangerous. These include visibility reduction due to tiny particles suspended in air, or bad odors, such as the rotten egg smell produced by hydrogen sulfide emanating from pulp and paper mills.