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Air_Pollution

2013-11-13 来源: 类别: 更多范文

Air Pollution Humans probably first experienced harm from air pollution when they built fires in poorly ventilated caves. Since then, we have gone on to pollute more of the earth's surface. Until recently, environmental pollution problems have been local and minor because of the Earth's own ability to absorb and purify minor quantities of pollutants. The industrialization of society, the introduction of motorized vehicles, and the explosion of the population are factors contributing toward the growing air pollution problem. At this time it is urgent that we find methods to clean up the air. The primary air pollutants found in most urban areas are carbon monoxide, nitrogen oxides, sulfur oxides, hydrocarbons, and particulate matter (both solid and liquid). These pollutants are dispersed throughout the world's atmosphere in concentrations high enough to gradually cause serious health problems. Serious health problems can occur quickly when air pollutants are concentrated, such as when massive injections of sulfur dioxide and suspended particulate matter are emitted by a large volcanic eruption. You cannot escape air pollution, not even in your own home. "In 1985 the Environmental Protection Agency (EPA) reported that toxic chemicals found in the air of almost every American home are three times more likely air, pollutants, dioxide, sulfur, smog, ozone, problems, pollution, sources, plants, coal, trees, oxides, one, nitrogen, miller, large, industrial, epa, damage, cause, carbon, about, suspended, result, oxygen, oil, liters, leaves, hydrocarbons, home, heavy, health, found, combustion
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