The pursuit that led to last week’s revelation started two years ago, when two members of the Texas team were at a conference, listening to accounts of the illness. Toxicologist Tom Kurt nudged epidemiologist Robert Haley and said it sounded a lot like OPIDN (organophosphate induced delayed neural toxicity), a syndrome in which chemical poisoning causes long-term nerve damage. OPIDN was first described during Prohibition, when it was linked to a contaminated Caribbean rum called Ginger Jake. The researchers knew that similar poisons are found in the insect repellents Deet and Permethrin, which were used topically or sprayed on uniforms during the war, and in pyridostigmine, which soldiers took as an anti-nerve-gas pill. So they started looking for a connection.
In the study reported last week, researchers treated chickens with nonlethal doses of all three agents. The birds receiving just one suffered no effects, but those exposed to any two of the chemicals showed signs of nerve damage. The chickens treated with all three showed extensive nerve damage–and, like some gulf-war veterans, they suffered tremors, weakness and a loss of muscle control in their legs.
The cholinesterase inhibitors are still only suspects. “We can’t extrapolate to humans,” Haley says. A second study, which involved monitoring 249 veterans from a mobile naval battalion, may strengthen the case. The researchers won’t discuss those findings until they’ve been reviewed for publication, but ailing veterans feel vindicated already. “This supports the position we’ve had all along,” says Matt Puglisi, the American Legion’s gulf-war spokesman. “There may be a new disease caused by chemical exposure.” Alas, knowing what caused the condition won’t reverse it.
