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建立人际资源圈Arsenic
2013-11-13 来源: 类别: 更多范文
Arsenic
Arsenic is a naturally occurring element found in our Earths crust, but too much of the element in our water systems, aquifers and wells could cause serious health problems over a long period of time. It has no distinctive taste or smell. You would assume that because arsenic is a naturally occurring element it wouldnt even be a concern. Arsenic causes a very serious environmental problem by contaminating our drinking water, and causing many diseases in people all over the world.
In an article by the Iowa Department of Natural Resources they explain that at very low levels arsenic is not a problem, in fact the body may even need a very small amount to function. However at higher levels, as low as three micrograms per liter, it could have a very serious effect on peoples health.(1) The main cause of arsenic in the drinking water is the weathering and decomposition of soil and minerals that occurs naturally. When the water comes in contact with these materials it can dissolve the arsenic. Industrial factories also introduce it by the combustion of fossil fuels, and they can also release hazardous waste into
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