Agent Orange

Agent Orange is a herbicide and defoliant chemical. 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 was a mixture of equal parts of two herbicides, 2,4,5-T and 2,4-D. The chemical damaged the health of people who came in in contact with it as well as extensively contaminated the environment.

The extensive environmental damage that resulted from the herbicide prompted the United Nations to pass Resolution 31/72 and ratify the Environmental Modification Convention. Many states do not regard this as a complete ban on the use of herbicides and defoliants in warfare but it does require case-by-case consideration.

In the Conference on Disarmament, Article 2(4) Protocol III of the weaponry convention contains "The Jungle Exception", which prohibits states from attacking forests or jungles "except if such natural elements are used to cover, conceal or camouflage combatants or military objectives or are military objectives themselves". This exception voids any protection of any military and civilian personnel from a napalm attack or something like Agent Orange and is clear that it was designed to cover situations like U.S. tactics in Vietnam. This clause has yet to be revised.

The main ingredients of Agent Orange comprise an equal mixture of two phenoxyl herbicides – 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) – in iso-octyl ester form, which contained traces of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

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