Agent Orange, herbicide used by U.S. forces during the Vietnam War to expose enemy guerrilla forces in forested areas. Agent Orange contains varying amounts of dioxin. Exposure to the defoliant has been linked with chemical acne, non-Hodgkin's lymphoma, Hodgkin's disease, and soft-tissue sarcoma. Many soldiers were exposed to Agent Orange in the Vietnam War. Afflicted veterans brought a class-action suit against manufacturers of Agent Orange, which was settled out of court by the establishment of a fund to compensate them and their families for any disabilities. That settlement, however, covered only those who became ill by 1994 and, as a result of a 2003 Supreme Court decision, veterans who became ill after 1994 can sue the herbicide's manufacturers. The herbicide has also been blamed for a significantly higher than normal rate of birth defects in areas of Vietnam that were sprayed; tests have shown persistent high levels of dioxin in the local environment and in people living there.

Mixture of herbicides. It contains approximately equal amounts of esters of 2,4-D (2,4-dichlorophenoxyacetic acid) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) and trace amounts of dioxin. About 13 million gallons were sprayed by U.S. military forces onto Vietnam's forests and crops during the Vietnam War, with the dual purpose of destroying cover for enemy movements and destroying food sources. Exposure to Agent Orange has been blamed for an abnormally high incidence of miscarriages, skin diseases, cancers, birth defects, and malformations among Vietnamese and of cancers and other disorders in U.S., Australian, and New Zealand servicemen and their families.

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