WASHINGTON -- Animal experiments at Duke University Medical Center show
that harmless doses of three chemicals used to protect Gulf War soldiers
from insect-borne diseases and nerve-gas poisoning are highly toxic when
used in combination, researchers reported Wednesday. They said the findings
may explain the wide array of symptoms reported by an estimated 30,000 Gulf
War veterans.
In studies using chickens, the researchers specifically found that two pesticides,
DEET and permethrin, and the anti-nerve gas agent pyridostigmine bromide
(PB) were harmless when used alone, even at three times the doses soldiers
likely received. But when used in combination, the chemicals caused neurological
deficits in the test animals similar to those reported by some Gulf War
veterans, according to Duke pharmacologist Mohamed Abou-Donia and Tom Kurt,
a toxicologist at The University of Texas Southwestern Medical Center in
Dallas.
Chickens were selected over rodents as test animals because their susceptibility
to neurotoxic chemicals more closely resembles that of humans, the scientists
said.
The findings were prepared for presentation Wednesday at the annual meeting
of the Federation of American Societies for Experimental Biology and will
be published in the May issue of the Journal of Toxicology and Environmental
Health.
The researchers said their findings are similar to those reported in Scotland
last month and by an Israeli team last year.
Adding to those findings, the Duke and UT Southwestern scientists have developed
a theory to explain why the chemical mix is dangerous. They said their results
indicate the anti-nerve gas agent reduces the body's normal ability to inactivate
the two pesticides, which can then travel to and damage the brain and nervous
system. Such a mechanism could explain the wide array of symptoms reported
by some Gulf War veterans, including memory loss, headache, fatigue, muscle
and joint pain, weakness, short
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Contact: Rebecca Levine
levin005@mc.duke.edu
919-660-1308
Duke University
29-Apr-1996