U.S. military spokesmen defend the use of defoliants in Vietnam at a news conference in Saigon, claiming that the use of the agents in selected areas of South Vietnam had neither appreciably altered the country's ecology, nor produced any harmful effects on human or animal life.
However, a paper released at the same news conference by Dr. Fred T. Shirley, a U.S. Agriculture Department expert, suggested that U.S. officials in Saigon were underestimating the extent of ecological damage caused in Vietnam by defoliating agents and that they had caused "undeniable ecological damage" and that "recovery may take a long time." Defoliation had been used in Vietnam since 1961 to reduce the dense jungle foliage so communist forces could not use it for cover, as well as to deny the enemy use of crops needed for subsistence. During a nine-year period ending in 1971, over 19 million gallons of three major herbicides (Agents Orange, White, and Blue) would be used in Vietnam. As part of Operation Ranch Hand, conducted from 1962 to 1970, specially equipped C-123 aircraft sprayed these herbicides in a 300-foot swath about eight and half miles long. It was also applied by helicopter, truck, and hand sprayers. The heaviest use of the defoliants was in the III Corps Tactical Zone north of Saigon and along the Cambodian and Laotian borders. The use of these agents was controversial, both during and after the war, because of the questions about long-term ecological impacts and the effect on humans who were either sprayed or handled the chemicals. Beginning in the late 1970s, Vietnam veterans began to cite the herbicides, especially Agent Orange, as the cause of health problems ranging from skin rashes to cancer and birth defects in their children. Similar problems, including an abnormally high incidence of miscarriages and congenital malformations, have been reported among the Vietnamese people who lived in the areas where the defoliate agents were used.