Agent Orange refers to a group of herbicides that were sprayed over Vietnam and Laos by the U.S. military during the Vietnam War. These chemicals have been subsequently linked to certain cancers and a variety of other illnesses that later developed in veterans of the war. Although the American Cancer Society, or ACS, reports that most studies of Vietnam War veterans have not shown an increase in respiratory cancers, including lung cancer, the U.S. Department of Veterans Affairs acknowledges that there is a correlation.
Herbicide Use During the Vietnam War
During the 1960s and early 1970s of the Vietnam War era, millions of gallons of plant-killing chemicals, or herbicides, were sprayed on the crops, forest cover and other vegetation of Vietnam and Laos. The spraying, known as Operation Ranch Hand, spanned 1962 to 1971. Soldiers serving during that period had exposure through breathing the chemicals, absorption through the skin or ingesting them through contaminated food and water. It's also possible the chemicals could have been absorbed through the eyes or breaks in the skin, according to the ACS.
Agent Orange and Dioxins
The herbicides used during the war came in drums with orange stripes, which is how the name 'Agent Orange' was coined, the ACS says. Most of these drums contained a mixture of 2,4-dichlorophenoxyacetic acid, or 2,4-D, and 2,4,5-trichlorophenoxyacetic acid, or 2,4,5-T. But Agent Orange now refers to all herbicides that were used at the time. 2,4,5-T was unintentionally contaminated with dioxins during the manufacturing process. Dioxins constitute a family of 75 related chemicals that are formed during the process of making paper, among other industrial processes. The primary dioxin in Agent Orange is 2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD. A study conducted in 1970 found that 2,4,5-T could cause birth defects in lab animals. As a result, all military herbicide use in Vietnam was halted in 1972. By then it was too late. Throughout the 1970s, veterans reported various illnesses including cancer, birth defects and handicaps in their children, strange skin rashes and psychological symptoms, among other things.
Lung and Other Respiratory Cancers
According to the ACS, most studies of Vietnam War veterans have not shown an increase in respiratory cancers, which includes lung, wind-pipe and voice-box cancer. Studies of manufacturing plant workers, farmers and herbicide applicators also found no excessive risk of lung cancer. The Institute of Medicine of the National Academy of Sciences has said that associations linking development of respiratory cancers and exposure to dioxin were found consistently only with high or prolonged herbicide exposure. For this reason, evidence linking Agent Orange to any of the respiratory cancers has been deemed "limited or suggested" only.
Other Cancers Linked to Agent Orange
The ACS says many questions regarding the health effects of Agent Orange have yet to be answered. But there is sufficient evidence to suggest that Agent Orange is associated with Hodgkins disease, non-Hodgkins lymphoma, lymphocytic leukemia and soft tissue sarcoma.
The Agent Orange Settlement Fund
In 1979, a large class action was filed against herbicide manufacturers and later settled out of court in 1984. The Agent Orange Settlement Fund, as it was called, constituted nearly $200 million and was distributed to veterans from 1988 to 1996.
