Toxicological Profile for DDT, DDE, and DDD (September 2002)

摘要

DDT (1,1,1-trichloro-2, 2-bis(p-chlorophenyl)ethane) is a pesticide that was once widely used to control insects on agricultural crops and insects that carry diseases like malaria and typhus, but is now used in only a few countries to control malaria. Technical-grade DDT is a mixture of three forms, p,p-DDT (85%), o,p-DDT (15%), and o,o-DDT (traceamounts). All of these are white, crystalline, tasteless, and almost odorless solids. Technical grade DDT may also contain DDE (1,1-dichloro-2,2-bis (p-chlorophenyl)ethylene) and DDD (1,1-dichloro- 2,2-bis(p-chlorophenyl) ethane) as contaminants. DDD was also used to kill pests, but to a far lesser extent than DDT. One form of DDD (o,p-DDD) has been used medically to treat cancer of the adrenal gland. Both DDE and DDD are breakdown products of DDT. DDT does not occur naturally in the environment. After 1972, the use of DDT was no longer permitted in the United States except in cases of a public healthemergency. It is, however, still used in some other areas of the world, most notably for controlling malaria. The use of DDD to kill pests has also been banned in the United States. This toxicological profile for DDT, DDE, and DDD is prepared in accordance with guidelines* developed by the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA). The profile includes the following: The examination, summary, and interpretation of available toxicologic information and epidemiologic evaluations on a hazardous substance to ascertain the levels of significant human exposure for the substance and the associated acute, subacute, and chronic health effects; A determination of whether adequate information on the health effects of each substance is available or in the process of development to determine levels of exposure that present a significant risk to humanhealth of acute, subacute, and chronic health effects; and Where appropriate, identification of toxicologic testing needed to identify the types or levels of exposure that may present significant risk of adverse health effects in humans.