Agents of Controversy
Critics of the use of herbicides were vocal during the Vietnam War and again when questions were raised in this country about the effects of the ominously named Agent Orange. The debate still rages.
US forces used 10 different herbicides in Southeast Asia, most of them variants of 2,4-D (D for dichlorophenoyxyacetic acid) or 2,4,5-T (T for trichlorophenoxyacetic acid). Others included sodium salt of cacodylic acid and triisopropanolamine salt of picloram.
The names "Pink," "Green," "Purple," "Blue," "Orange," and so on came from the 4-inch-wide band painted on the 55-gallon drums containing the herbicide. The herbicide contained in orange-striped drums came to be called "Agent Orange." A 50 - 50 solution of 2,4-D and 2,4,5-T, it was the most widely used of the herbicides and gained the most notoriety.
All of the herbicides used in Southeast Asia had been used in commercial agriculture for many years. As an example, in the United States in 1961, about 40 million acres were treated with 2,4-D and 2,4,5-T herbicides.
Among the many myths about herbicide spraying was that forest areas were "drenched" with spray that "soaked" clothing of those on the ground. In actual practice, the dispensation of three gallons of herbicide per acre is the equivalent of about .009 of an ounce per square foot. In most instances, only about 6 percent of the sprayed material reached the ground, the rest being absorbed by the jungle foliage. Drenching and soaking did not occur.
Dioxin was present in Agent Orange, but only as a trace amount -.0002 of 1 percent, and this amount was degradable by sunlight within 72 hours.
Over the past 18 years, Ranch Hand veterans have participated in a $120 million epidemiological study - the Air Force Health Study, commonly called the Ranch Hand Study. The participants received physical exams in 1982, 1985, 1987, 1992, and 1997. The final physical exams are scheduled for 2002. Although Ranch Hand personnel naturally had the greatest degree and frequency of contact with the herbicides, physical examinations at the Kelsey - Seybold clinic in Houston and the Scripps Clinic and Research Foundation in La Jolla, Calif., reveal that the mortality rate of the group is the same as a matched comparison group (Air Force veterans who flew in C-130s in Southeast Asia during the Ranch Hand time frame) and significantly lower than the rate for the male population of the United States. The number of birth defects among children of Ranch Hand veterans is the same as the children of the comparison group.
The testing of Ranch Hand veterans will conclude in 2006, at which time a report will be prepared.