Vietnam veterans who sprayed the herbicides like Agent Orange decades ago in Vietnam are at an increased risk of developing heart disease, diabetes, high blood pressure, and chronic breathing problems, a new study shows.
Agent Orange, a weed killer containing dioxin, was widely used during the Vietnam War, Dr Han K. Kang of the Department of Veterans Affairs in Washington, DC and colleagues note in the American Journal of Industrial Medicine.
Overall, two thirds of the herbicides used during the conflict contained dioxin. To understand the long-term effects of exposure to the chemicals, Kang and his team compared 1,499 members of the US Army Chemical Corps to 1,428 vets who had worked in chemical operations jobs but did not serve in Vietnam.
The Chemical Corps members had been responsible for spraying herbicide around base camp perimeters, as well as aerial spraying of the chemicals from helicopters.
Study participants were surveyed by telephone in 1999 and 2000. Tests of a subset of the study participants, including 795 Vietnam vets and 102 non-Vietnam vets, showed the Vietnam vets had higher levels of dioxin in their blood. The researchers analyzed the effects of Vietnam service and herbicide exposure separately, and found that hepatitis was the only health problem linked to serving in Vietnam per se.
However, exposure to herbicides among Vietnam veterans conferred a 50 percent increased risk of diabetes, a 52 percent greater heart disease risk, a 32 percent increased risk of hypertension and a 60 percent greater likelihood of having a chronic respiratory problem such as emphysema or asthma. An increased cancer risk also was seen among the Chemical Corps members, but this was not significant from a statistical standpoint.
"Almost three decades after Vietnam service," the researchers conclude, "US Army veterans who were occupationally exposed to phenoxyherbicide in Vietnam experienced significantly higher risks of diabetes, heart disease, hypertension, and non-malignant lung diseases than other veterans who were not exposed to herbicides."