WASHINGTON -- A Pentagon-sponsored study raises the possibility that some of the undiagnosed illnesses reported by Gulf War veterans could be explained by their exposure to low levels of Iraqi nerve gas.
The report released Tuesday found no evidence in available scientific literature, however, to support the idea that symptoms linked to nerve gas would appear two or more years after exposure. About half of Gulf War veterans reporting health problems did so a year or more after returning to the United States.
The report, by the Rand Corp.'s federally funded National Defense Research Institute, does not provide a final answer to the question that has lingered since the end of the Gulf War: Was exposure to chemical warfare agents responsible for some of the neurological and other health problems reported by veterans?
"It is not possible to eliminate nerve agents categorically from playing a role in some cases of illnesses of Gulf War veterans," the report said. But, it added, it is "difficult to accept" that exposures affecting large numbers of troops would have escaped notice.
The report called for more research into the long-term health effects of exposure to levels of nerve gas such as those experienced by approximately 100,000 American soldiers at Khamisiyah, an Iraqi ammunition depot that U.S. soldiers blew up several days after the Gulf War ended. It was discovered later that the depot contained hundreds of weapons filled with lethal sarin gas.
The Pentagon on Tuesday said it has determined that one of the nerve agents present at Khamisiyah -- cyclosarin -- is two to three times more toxic than sarin, the predominant nerve agent used in 122mm rockets destroyed at the depot. Cyclosarin also is less volatile than sarin, meaning it evaporates more slowly.
Thus, even though the Pentagon now believes the total amount of nerve agent released by the Khamisiyah demolition on March 10, 1991, was less than originally calculated, the toxic effect from the resulting plume is about the same because of the newly included information about the toxicity and volatility of cyclosarin.
Three years ago, the Pentagon notified about 99,000 troops that they were exposed to a plume of sarin gas from Khamisiyah. On Tuesday, the Pentagon announced that 32,806 of those troops were not in the path of the sarin-cyclosarin gas plume and thus were not exposed; on the other hand, it has determined that 34,819 soldiers previously believed to have been beyond the plume actually were exposed.
The net result: About 2,000 more troops were exposed to the gas plume than previously believed. The new figures are derived from more precise data on troop placement and weather patterns.
Bernard Rostker, the undersecretary of defense for personnel, told a Pentagon news conference that letters were mailed Tuesday notifying all affected soldiers. The letter assures the exposed soldiers, "There is no indication that any long-term health effects would be expected from the brief, low-level exposure to chemical agents that may have occurred near Khamisiyah."
The Rand study does not contradict that statement, but it does raise the possibility of health problems.
"It is not possible to dismiss low-dose exposures to one or more of the agents or the possibility that such exposures contributed to some of the symptoms experienced by Gulf War veterans," it concluded.
Rostker said that between 10,000 and 12,000 Gulf War veterans have reported undiagnosed health problems. More than half a million U.S. troops served in the war.
On the Net:
Pentagon's Gulf War illness office: http://www.gulflink.osd.mil