In 1943, the United States Department of the Army contracted botanist (and later bioethicist) Arthur Galston, who discovered the defoliants later used in Agent Orange, and his employer University of Illinois Urbana-Champaign to study the effects of 2,4-D and 2,4,5-T on cereal grains (including rice) and broadleaf crops. These included 2,4-D, 2,4,5-T, MCPA (2-methyl-4-chlorophenoxyacetic acid, 1414B and 1414A, recoded LN-8 and LN-32), and isopropyl phenylcarbamate (1313, recoded LN-33). Several herbicides were developed as part of efforts by the United States and the United Kingdom to create herbicidal weapons for use during World War II. government reports, if not bound chemically to a biological surface such as soil, leaves or grass, Agent Orange dries quickly after spraying and breaks down within hours to days when exposed to sunlight and is no longer harmful. When TCDD binds to AhR, the protein moves to the nucleus, where it influences gene expression. Dioxin enters the body by attaching to a protein called the aryl hydrocarbon receptor (AhR), a transcription factor. Dioxins accumulate easily in the food chain. The fat-soluble nature of TCDD causes it to enter the body readily through physical contact or ingestion. TCDD is the most toxic of the dioxins and is classified as a human carcinogen by the U.S. TCDD was a trace (typically 2-3 ppm, ranging from 50 ppb to 50 ppm) - but significant - contaminant of Agent Orange. The active ingredient of Agent Orange was an equal mixture of two phenoxy 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 the dioxin 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD). military in Laos and Cambodia during the Vietnam War because forests near the border with Vietnam were used by the Viet Cong.Ĭhemical composition 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) 2,4-dichlorophenoxyacetic acid (2,4-D) 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and Vietnamese veterans sought compensation for damages.Īgent Orange was first used by the British Armed Forces in Malaya during the Malayan Emergency. The United Nations ratified United Nations General Assembly Resolution 31/72 and the Environmental Modification Convention. The use of Agent Orange in Vietnam resulted in numerous legal actions. The environmental destruction caused by this defoliation has been described by Swedish Prime Minister Olof Palme, lawyers, historians and other academics as an ecocide. Animal species diversity is sharply reduced in contrast with unsprayed areas. Defoliants eroded tree cover and seedling forest stock, making reforestation difficult in numerous areas. Agent Orange has also caused enormous environmental damage in Vietnam. An epidemiological study done by the Centers for Disease Control and Prevention showed that there was an increase in the rate of birth defects of the children of military personnel as a result of Agent Orange. The United States government has described these figures as unreliable, while documenting cases of leukemia, Hodgkin's lymphoma, and various kinds of cancer in exposed U.S. The government of Vietnam says that up to four million people in Vietnam were exposed to the defoliant, and as many as three million people have suffered illness because of Agent Orange, while the Vietnamese Red Cross estimates that up to one million people were disabled or have health problems as a result of exposure to Agent Orange. Nine chemical companies produced it: Dow Chemical Company, Monsanto Company, Diamond Shamrock Corporation, Hercules Inc., Thompson Hayward Chemical Co., United States Rubber Company (Uniroyal), Thompson Chemical Co., Hoffman-Taff Chemicals, Inc., and Agriselect. military procured over 20 million gallons (75 million liters), consisting of a fifty-fifty mixture of 2,4-D and dioxin-contaminated 2,4,5-T. In addition to its damaging environmental effects, traces of dioxin (mainly TCDD, the most toxic of its type) found in the mixture have caused major health problems for many individuals who were exposed, and their offspring.Īgent Orange was produced in the United States from the late 1940s and was used in industrial agriculture, and was also sprayed along railroads and power lines to control undergrowth in forests. It is a mixture of equal parts of two herbicides, 2,4,5-T and 2,4-D. military as part of its herbicidal warfare program, Operation Ranch Hand, during the Vietnam War from 1961 to 1971. Agent Orange is a chemical herbicide and defoliant, one of the tactical use Rainbow Herbicides.
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