Agent Orange was the code name for a herbicide developed for the military, primarily
for use in tropical climates. Although the genesis of the product goes back to the 1940's,
serious testing for military applications did not begin until the early 1960's.
The purpose of the product was to deny an enemy cover and concealment in dense
terrain by defoliating trees and shrubbery where the enmy could hide. The product
"Agent Orange" (a code name for the orange band that was used to mark the drums it
was stored in, was principally effective against broad-leaf foliage, such as the dense
jungle-like terrain found in Southeast Asia.
The product was tested in Vietnam in the early 1960's, and brought into ever widening
use during the height of the war (1967-68), though it's use was diminished and
eventually discontinued in 1971.
Agent Orange was a 50-50 mix of two chemicals, known conventionally as 2,4,D and
2,4,5,T. The combined product was mixed with kerosene or diesel fuel and dispersed by
aircraft, vehicle, and hand spraying. An estimated 19 million gallons of Agent Orange
were used in South Vietnam during the war.
The earliest health concerns about Agent Orange were about the product's
contamination with TCDD, or dioxin. TCDD is one of a family of dioxins, some found in
nature, and are cousins of the dibenzofurans and pcb's.
The TCDD found in Agent Orange is thought to be harmful to man. In laboratory tests
on animals, TCDD has caused a wide variety of diseases, many of them fatal. TCDD is
not found in nature, but rather is a man-made and always unwanted byproduct of the
chemical manufacturing process. The Agent Orange used in Vietnam was later found to
be extremely contaminated with TCDD.