the insecticidal properties of DDT, a whit crystalline compound, were discovered in 1942. during world war II this pesticide was used to control the spread use of typhus and malaria. then in the postwar era it began to be used extensively as an agricultural insecticide. its success in eradicating malaria and controlling other insect-borne diseases dangerous both to humans and crops led it to be labeled a miracle pesticide.
its usage increased and peaked in the early 1960s. in that decade, however, studies began to show that this method of pest control had serious environmental consequences. perhaps most damaging for the reputation of DDT was the wide popularity of Rachel Carsson's book Silent Spring, which exposed the dangers of continued use of this pesticide on bird and animal species and ultimately on human beings. carson's influential expose of the harmful effects of DDT showed that several species of birds were experiencing population declines as a result of ingesting this chemical in their customary diet. research showed that birds of prey such as the bald eagle and peregrine falcon, which are high on the food chain, accumulated excessive amounts of the pesticide in their bodies, and this caused them to lay eggs with thin shells, which would break before hatching. research also showed that the human population was at risk from increased levels of liver and breast cancer caused by exposure to DDT. furthermore, environmentalists pointed out that the toxicity of this substance is not easily degraded and can remain in the environment and food chain for prolonged periods. due to these reasons, and also to the fact that DDT seemed to be losing its effectiveness on the insect populations it was designed to control, many countries banned the use of this product during the early 1960s.
pesticide was used to control the spread use of typhus and malaria. then in the postwar era it began to be used extensively as an agricultural insecticide. its success in eradicating malaria and controlling other insect-borne diseases dangerous both to humans and crops led it to be labeled a miracle pesticide.
its usage increased and peaked in the early 1960s. in that decade, however, studies began to
show
that this method of pest control had serious environmental consequences. perhaps most damaging for the reputation of ddt was the wide popularity of Rachel Carsson's book Silent Spring, which exposed the dangers of continued use of this pesticide on bird and animal species and ultimately on human beings. carson's influential expose of the harmful effects of ddt
showed
that several species of birds were experiencing population declines as a result of ingesting this chemical in their customary diet. research
showed
th
