LOS ANGELES: A review of medical studies on Gulf War syndrome supports the theory that the still-hazy disorder was caused by a group of related chemicals found in pesticides used around military facilities and anti-nerve gas pills given to soldiers, according to a study released on Monday.

A similar chemical was found in nerve gas that was inadvertently released when US soldiers destroyed a munitions depot just after the 1991 war, according to the study published in the Proceedings of the National Academy of Sciences.

The group of chemicals, known as acetylcholinesterase inhibitors, has long been discussed as a possible cause of Gulf War syndrome.

The review “thoroughly, conclusively shows that this class of chemicals actually are a cause of illness in Gulf War veterans”, said Dr Beatrice Golomb, an associate professor of medicine at the University of California, San Diego and the author of the latest paper. Other researchers, however, said the syndrome’s symptoms are so varied that it’s probably difficult to place the blame on a single cause.

“It seems clear at this point, 17 years beyond the conflict, that the chances we will ever resolve this with any single ‘smoking gun’ exposure grows smaller with time,” said Dr Charles Engel, director of the Department of Defence Deployment Health Clinical Center at Walter Reed Army Medical Center in Washington.

Gulf War syndrome is a complex and controversial illness typically characterized by symptoms that include fatigue, muscle or joint pain and mood problems. About 200,000 veterans are believed to suffer from it, according to the study.

But there is still uncertainty. A panel of the federal Institute of Medicine said in 2006 that it could not say if there was a coherent set of symptoms that pointed to an identifiable syndrome.

Researchers have proposed a number of potential causes, including psychological stressors and exposure to toxic materials from oil-well fires and depleted-uranium ammunition, experts said. In toxic doses, acetylcholinesterase inhibitors cause unbridled signalling between cells, potentially leading to muscle paralysis, seizures and excess secretion in the airways.Previous studies have estimated that at least 250,000 soldiers were exposed to some form of the chemical.—Dawn/The LAT-WP News Service (c) Los Angeles Times