BIOLOGY IN HUMAN WELFARE
HUMAN HEALTH AND DISEASE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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persistent
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synergistic
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acute
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threshold
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Detailed explanation-1: -Microorganisms in the soil slowly break down DDT (it can take anywhere from 2 to 15 years to break down half of the DDT). DDT does not dissolve easily in water and is mostly found in the sediment on the bottom of bodies of water. DDT, DDE, and DDD can build up in plants and animals.
Detailed explanation-2: -DDT lasts a very long time in soil. Half the DDT in soil will break down in 2–15 years. Some DDT will evaporate from soil and surface water into the air, and some is broken down by sunlight or by microscopic plants or animals in soil or surface water. DDT in soil usually breaks down to form DDE or DDD.
Detailed explanation-3: -DDT is an extremely persistent compound due to its near insolubility in water and tendency to bioaccumulate in fatty tissue and biomagnify throughout trophic levels. By 1972, DDT use was banned in the United States and worldwide production and use began to decrease as well.
Detailed explanation-4: -DDT is a persistent organic pollutant (POP). It is made by humans and does not occur naturally in the environment. DDT was used as an insecticide to prevent the spread of disease and to protect crops.