RAINBOW Herbicides

(the Vietnam war, 1954-75)Agent Orange

Fought between communist North Vietnam and South Vietnam(gov). Viet cong were rebels in the South who fought against the gov+USA.North was supported by China, Soviets (other communist countries) and the South by America.North won (arguably.)

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Photo-1972 when a south vietnamese plane dropped napalm on own troops and civillians

3Why were the herbicides used?

Part of operation ranch hand 61-71Initially intended as a defoliant because the forests in Vietnam provided cover for enemy side, and so south teamed up with america and sprayed south1940s discovered, guy looking for a way to speed up plant growth, a little was fine but high concentrations caused plants leaves to fall off, killing the plants4Unforeseen Consequences

Herbicides used contained a dangerous chemical called dioxin which causes all sorts of problems, its a carcinogen, respiratory problems, skin problems and bodily deformities- spina bifidaDioxin is a general term5TCDD

2378 tetra chloro dibenzodioxin (TCDD)Not absorbed by plants or soluble but can attach to soil particles which are then carried downstream, settle at bottom of ponds/lakes affects people who eat fish/drink water. Fish is a major food source in vietnam.Toxic over a long period of time, half life in humans is 7 years.6

Viktor Yushchenko ingested less than 1mgIt is present in our food chains even now, as it accumalates in fatty tissue (fat soluble) and if it finds its way in to animals then it finds its way in to us, or even vegetation7

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When a pregnant woman is exposed it can enter embryo through blood stream. Dioxin is taken up by attaching to an inactive protein in the cytoplasm of cells called aryl hydrocarbon receptor. When they bind the protein moves to the nucleus where it can influence gene expression.

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