HEADLINE Air force study finds link between diabetes, Agent Orange

BYLINE Jim Mannion

DATELINE WASHINGTON, March 29

The US Air Force has found a strong link between adult onset

diabetes and dioxin exposure among US pilots and ground crews who were

exposed to the herbicide Agent Orange during the Vietnam War, the

senior investigator announced Wednesday.

Joel Michalek, who leads the Air Force Health Study, said a recent

study found "the strongest evidence to date that exposure to Agent

Orange is associated with adult onset diabetes" among those who were

involved in the aerial spraying of the chemicals.

"A 47 percent increase in diabetes was seen in those veterans with the

highest levels of dioxin," Michalek said. "This is particularly strong

evidence since dioxin is that component of Agent Orange that has been

linked to health effects in laboratory animals."

The results suggested that the higher the dioxin level, the greater

the severity of the disease and the more quickly it manifested itself,

he said.

Veterans groups expressed hope that the latest findings mean that

diabetes will be added to the list of nine other diseases for which

Vietnam veterans are eligible for disability compensation.

The list currently includes chloracne, Hodgkin's disease, multiple

myeloma, non-Hodgkin's lymphoma, porphyria cutanea tarda, respiratory

cancers, soft tissue sarcoma, peripheral neuropathy and prostate

cancer.

The air force scientists first reported a link between diabetes and

dioxin in 1991 but did not announce it formally until now because the

results were "unexpected" and the researchers felt they needed further

analysis, Michalek said.

The air force study tracks 1,000 participants in the air force's

Operation Ranch Hand, which dumped 19 million gallons of Agent Orange

over Vietnam between 1962 and 1971 to defoliate jungle that Viet Cong

and North Vietnamese forces used as cover.

The Ranch Hand participants, who have undergone physical examinations

every five years since 1982, were compared to a control group

consisting of pilots and ground crews who served in Vietnam but not in

the aerial spraying program.

Besides diabetes, the study also found mixed evidence suggesting a

link between dioxin exposure and heart disease, Michalek said.

It said were 26 percent more likely to develop heart disease than the

control group. For flyers, the risk of heart disease was more than

double. But for ground crews, who had the highest dioxin levels, there

was no significant increase in risk.

The air force study also found a "statistically significant increase

in neurological disease" in Ranch Hand participants, and that

peripheral disorders increased as levels of dioxin increased.

Consistent and significant increases in cholesterol, triglicerides and

cholesterol-HDL ratios among Ranch Hand participants were found.

The study found increases in certain liver enzymes, but "no evidence

of a corresponding increase in overt liver disease."

Although one of the largest studies of human exposure to dioxin, the

air force survey includes too few people to detect increases in rare

diseases.

It has found no evidence of an increased risk of cancer among Ranch

Hand veterans after 15 years, Michalek said.

In fact, among Ranch Hand ground crew members with the highest levels

of dioxin exposure the study is showing a 22 percent decreased risk of

cancer.

But Michalek said he expects the incidence of cancer to come into

clearer focus in coming years as the veterans enter ages in which

the disease is more prevalent.