<P> Agent Orange is an herbicide and defoliant chemical, one of the tactical use Rainbow Herbicides . It is widely known for its use by the U.S. military as part of its herbicidal warfare program, Operation Ranch Hand, during the Vietnam War from 1961 to 1971 . It is a mixture of equal parts of two herbicides, 2, 4, 5 - T and 2, 4 - D. In addition to its damaging environmental effects, traces of dioxin found in the mixture have caused major health problems for many individuals who were exposed . </P> <P> Up to four million people in Vietnam were exposed to the defoliant . The government of Vietnam says as many as 3 million people have suffered illnesses because of Agent Orange . The Red Cross of Vietnam estimates that up to 1 million people are disabled or have health problems as a result of Agent Orange contamination . The United States government has challenged these figures as being unreliable . The chemical is capable of damaging genes, resulting in deformities among the offspring of exposed victims . The U.S. government has documented higher cases of leukemia, Hodgkin's lymphoma, and various kinds of cancer in exposed veterans . Agent Orange also caused enormous environmental damage in Vietnam . Over 3,100,000 hectares (31,000 km or 11,969 mi) of forest were defoliated . Defoliants eroded tree cover and seedling forest stock, making reforestation difficult in numerous areas . Animal species diversity sharply reduced in contrast with unsprayed areas . </P>

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