That is the conclusion of researchers at Duke University Medical Center in North Carolina whose study based on animal experiments will be published today in the Journal of Toxicology and Environmental Health.
Mohamed Abou-Donia, professor of pharmacology and cancer biology at Duke and one of the study’s authors, said some cells responsible for the production and maintenance of sperm were damaged or killed by exposure to the three substances when combined: the insect repellent DEET, the insecticide permethrin and an anti-nerve gas drug known as pyridostigmine bromide, or PB.
“It appears moderate stress, combined with the three chemicals, caused the most severe deterioration in testicular structure and sperm production, and these conditions were likely experienced by some Gulf War soldiers in the combat environment,” Abou-Donia said.
He said the Department of Defense had funded the study because Gulf War veterans had expressed concern about infertility and sexual dysfunction.
The study is one of many investigating the causes of Gulf War illnesses, the puzzling array of medical problems that plague men and women who served in the Persian Gulf.
According to epidemiological studies, about 200,000 Gulf War veterans — out of 700,000 deployed — have suffered illnesses since the war.
During the war, troops were exposed to pesticides, chemical warfare agents, biological warfare agents, vaccines, PB (pyridostigmine bromide), infectious diseases, depleted uranium, oil well fires and smoke and petroleum products.
Veterans have long wondered what role exposure to that “cocktail” of substances has played in their ailments.
EXPOSURE AFFECTED FAMILY LIFE
Steve Robinson, executive director of the National Gulf War Resource Center,
a Washington, D.C., advocacy group for ailing veterans and their families, said no one kept statistics on how many Gulf War veterans suffered from infertility.
But Robinson said he had seen the emotional — and financial — devastation those problems had caused in their families.
“I know families who have spent their life savings trying to have children and have gone under,” he said. “I’ve seen marriages crumble. It’s a big deal.”
Barbara Goodno, a spokeswoman for the Pentagon’s Deployment Health Support office, which advises the agency on protecting the health of troops, declined comment, saying the office had not seen the study.
Professor Abou-Donia said soldiers had sprayed DEET on their skin, and several thousand of them wore uniforms impregnated with the pesticide permethrin.
In addition, 250,000 men and women took PB pills as a “pretreatment” to enhance the antidote effects of two other drugs used to protect against nerve agent poisoning.
RATS SHOW NO OUTWARD SIGNS
Abou-Donia said researchers mimicked conditions found during the Gulf War by exposing rats to a scaled-down dosage of the same three chemicals.
“Interestingly, the chemically treated rats don’t look or behave any differently than normal rats, just as the soldiers don’t show any outward signs of disease,” he said. “But under a microscope, you can see clear and well-defined damage to a variety of testicular structures.”
In a study published last year, Abou-Donia and fellow researchers found that rats exposed to the same trio of chemicals and stress suffered significant damage to the areas of the brain that control muscle strength and movement, balance and coordination, and memory and emotions.
Abou-Donia noted that veterans had complained of problems in those very same functions for more than a decade.
E-mail Kathleen Sullivan at ksullivan@sfchronicle.com.
