Agent Orange was a chemical defoliant used by the United States military during the Vietnam War that has since become recognized as a serious health hazard.
During the Vietnam War, U.S. forces tried to deny the enemy forest and jungle cover by spraying suspected hiding places with defoliants, the most common of which was a mixture called Agent Orange. Chemical defoliants intended to kill only plants with no known effects on humans are a blurry area under the Chemical Weapons Convention. Spraying was principally done from modified C-123 Provider light transport aircraft without extensive chemical protection for the crews. The program was called Operation Ranch Hand.
During the war, Agent Orange was considered nontoxic to humans and not targeted at food crops. It was primarily composed of commercial herbicides known as 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T). Many batches, however, had an exceptionally toxic byproduct of the manufacturing process, 2,3,7,8-tetrachlorodibenzo-p-dioxin (which can also be abbreviated as 2,3,7,8-TCDD). This byproduct caused significant contamination and long-term health consequences including birth defects. Agent Orange was also used by Canadian Forces in Canada, which later documented the health effects. 2,3,7,8-TCDD is now listed as a presumed carcinogen by the Environmental Protection Agency. The United States Department of Veterans Affairs (DVA) considers certain diseases contracted by Vietnam War veterans or birth defects in their children as presumptively caused by Agent Orange exposure. Medical care by the United States Veterans Health Administration and disability payments are covered by the DVA.
- Defence Canada, The Use of Herbicides at CFB Gagetown from 1952 to Present Day
- Environmental Protection Agency (January 2000), 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (2,3,7,8,-TCDD) (CAS 1746-01-6)Hazard Summary
- U.S. Department of Veterans Affairs, Agent Orange and Vietnam Veterans