dichloro diphenyl trichloroethane (DDT)

Definition

Non-water soluble chlorinated hydrocarbon in use since Second World War (1939-1945) as an insecticide for the control of lice (that spread typhus) and mosquitoes (that spread malaria and yellow fever). But its primary use was in agriculture to control plant pests, specially those affecting cotton and tobacco. Being non-biodegradable it persists in nature and climbs up the food chain by accumulating in body fat (in which it is soluble), causing widespread poisoning of birds and other small animals and plants. Even small concentrations of DDT (0.01 part per million) retard photosynthesis in plankton by 20 percent, and one part per billion (ppb) has been known to kill 39 percent of the sea water shrimp in three weeks. Since 1970s, its manufacture and use is restricted in most countries and banned in some. Although DDT was synthesized in 1874 by the German chemist Othmar Zeidler, its pesticidal properties were discovered only in 1939 by the Swiss chemist Paul Mueller who won the 1951 Nobel Prize in physiology & medicine. Chemical formula: (ClC6H4)2CHCCl3.

单词	dichloro diphenyl trichloroethane (DDT)
释义	dichloro diphenyl trichloroethane (DDT) Definition Non-water soluble chlorinated hydrocarbon in use since Second World War (1939-1945) as an insecticide for the control of lice (that spread typhus) and mosquitoes (that spread malaria and yellow fever). But its primary use was in agriculture to control plant pests, specially those affecting cotton and tobacco. Being non-biodegradable it persists in nature and climbs up the food chain by accumulating in body fat (in which it is soluble), causing widespread poisoning of birds and other small animals and plants. Even small concentrations of DDT (0.01 part per million) retard photosynthesis in plankton by 20 percent, and one part per billion (ppb) has been known to kill 39 percent of the sea water shrimp in three weeks. Since 1970s, its manufacture and use is restricted in most countries and banned in some. Although DDT was synthesized in 1874 by the German chemist Othmar Zeidler, its pesticidal properties were discovered only in 1939 by the Swiss chemist Paul Mueller who won the 1951 Nobel Prize in physiology & medicine. Chemical formula: (ClC6H4)2CHCCl3.
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