Ddt why was it banned

India is the only country still manufacturing the pesticide dichlorodiphenyltrichloroethane, better known at DDT. China ceased production of the chemical in The Stockholm Convention CoP-6 had aimed to establish a time frame for research into affordable alternatives to DDT, and to set as the deadline for the ban of the chemical. To this end, the convention wanted to establish a roadmap. Persistent pesticide DDT was developed in the s and was initially used with great effect to combat malaria, typhus, and the other insect-borne human diseases, and for insect control in crop and livestock production, institutions, homes, and gardens.

As Carson saw it, a race of super-insects, immune to the effects of pesticides, would infest the crops grown on American farms. Desperate farmers, she said, would respond to these infestations by using much greater quantities of DDT. The effective date of the EPA June cancellation action was delayed until the end of this year to permit an orderly transition to substitute pesticides, including the joint development with the U.

Department of Agriculture of a special program to instruct farmers on safe use of substitutes. The cancellation decision culminated three years of intensive governmental inquiries into the uses of DDT. As a result of this examination, Ruckelshaus said he was convinced that the continued massive use of DDT posed unacceptable risks to the environment and potential harm to human health.

DDT's quick success as a pesticide and broad use in the United States and other countries led to the development of resistance by many insect pest species. The U. Department of Agriculture, the federal agency with responsibility for regulating pesticides before the formation of the U.

Environmental Protection Agency in , began regulatory actions in the late s and s to prohibit many of DDT's uses because of mounting evidence of the pesticide's declining benefits and environmental and toxicological effects. The publication in of Rachel Carson's Silent Spring stimulated widespread public concern over the dangers of improper pesticide use and the need for better pesticide controls.

In , EPA issued a cancellation order for DDT based on its adverse environmental effects, such as those to wildlife, as well as its potential human health risks.

Since then, studies have continued, and a relationship between DDT exposure and reproductive effects in humans is suspected, based on studies in animals. In both these and other studies, no evidence of teratogenicity has been observed. IARC has concluded that while there is inadequate evidence for the carcinogenicity of DDT in humans, there is sufficient evidence in experimental animals.

DDT is highly toxic to fish, with hour LC50 values in the range of 0. It also affects fish behaviour. Atlantic salmon exposed to DDT as eggs experienced impaired balance and delayed appearance of normal behaviour patterns. DDT also affects temperature selection in fish. There is considerable variation in the sensitivity of bird species to this effect, with birds of prey being the most susceptible and showing extensive egg shell thinning in the wild.

American kestrels were fed day old cockerels injected with DDE. Residues of DDE in the eggs correlated closely with the dietary DDE concentration and there was a linear relationship between degree of egg shell thinning and the logarithm of the DDE residue in the egg. Data collected in the field has confirmed this trend. DDT in conjunction with other halogenated aromatic hydrocarbons has been linked with feminization and altered sex-ratios of Western Gull populations off the coast of southern California, and Herring Gull populations in the Great Lakes.

Bioconcentration factors of , and 51, have been recorded for fathead minnows and rainbow trout, respectively.