Navy scientists develop new testing capabilities to determine chemical warfare agent exposure

WASHINGTON, March 8, 2001 (GulfLINK) - The Department of Defense has approved a research project that will use newly developed testing capabilities and frozen blood samples from 1990-91 to determine whether members of a U.S. Marine Corps unit were exposed to certain chemical substances during their participation in the Gulf War.

The $705,000 project will be led by Navy Captains Craig Hyams, M.D. and J.D. Malone, M.D., both infectious disease specialists. The study will be a collaborative effort, which will include researchers from the Department of Veterans Affairs, the Centers for Disease Control and Prevention, and the U.S. Army Center for Health Promotion and Preventive Medicine.

The project's roots are found in U.S. Navy surveillance work done by Hyams and Malone 10 years ago when they administered health evaluation questionnaires and drew blood samples from about 1,000 Marines. The first questionnaires were administered and the first blood samples were drawn in December 1990, a few days prior to the unit's deployment to Southwest Asia. The questionnaire sought demographic data and information about previous overseas assignments.

Within a few days of their return, in May 1991, about 900 of the original cohort of Marines were administered a second questionnaire and submitted a second blood sample. The second questionnaire sought information about the Marines' general health and symptoms during deployment. Portions of both blood samples were analyzed for exposure to infectious diseases. The remainder of the samples were frozen.

At the time of the war, Hyams and Malone were focused on infectious diseases and conducted tests on the sera for such diseases as sand fly fever, Norwalk virus infections, Shigella virus, and number of other types of viruses indigenous to the Gulf region. These studies showed that Gulf War troops were frequently exposed to the bacteria which commonly causes traveler's diarrhea but there was no evidence of exposure to sand fly fever. In order to preserve this resource for future analysis, both the pre-deployment and post-deployment sera samples have remained frozen at minus 70 degrees Celsius since being taken from the Marines.

"There are no sample collections like this one, where we obtained information and blood samples just before they left and just after they returned," Hyams says. "Having a pre- and a post-deployment sample, plus health data collected from veterans at the end of the war, is what makes this so valuable. We know what they were like when they left and we know what they were like when they returned."

These Marines initially were deployed to Saudi Arabia, but then saw action in Kuwait during the war.

"This cohort appeared healthy when they returned, though they reported experiencing the same kinds of general symptoms and illnesses in the desert that other veterans reported when they came home," Malone recalls.

Within the past year, however, new techniques have been developed that allow CDC scientists to test those sera samples in ways they were unable to test in the past. This new capability means that Hyams and Malone and their research team for the first time will be able to test the Marines' sera for chemical warfare agents, organophosphate and chlorinated pesticides, sulfur mustard and smoke from oil well fires.

"This is totally new," Hyams said. "Only in the last year has it been possible to begin developing this capability at the CDC, which allows us to test the serum samples collected near the time of exposure."

That will be the focus of the team's work over the next eighteen months. The team plans to compile a comprehensive profile of the Marine unit to include the information contained on the pre- and post-deployment questionnaires, their geographic locations while in the region and the health problems they have encountered since their return.

Hyams is quick to point out that this research project has its limitations. For example, the testing methodology is so new that its accuracy is not yet known. Therefore, one of the major goals of this study is to evaluate these new tests.

The experimental nature of the tests also means that it may not be possible to say definitely whether an evaluated veteran was exposed to a particular chemical substance.

Also, the number of troops is small. Only about 100 randomly selected veterans can be tested initially. Since only 100 individual veterans can be tested, their locations and exposures are restricted to a few areas in northern Saudi Arabia and Kuwait. Consequently, the research findings may not be applicable to other units located elsewhere in the theater.

"We are going to learn something from this research, but it may not answer individual veteran's questions," he says.

Nevertheless, Hyams believes the project will have important long-term benefits by leading to new monitoring and testing methods that will stimulate the development of simple and effective procedures to assess military personnel for exposure to toxic agents in future conflicts. In addition, the project will develop a new database for future analysis of adverse exposures during the Gulf War as new tests and hypotheses are developed.

One hundred of the Marines who participated in the original questionnaire and blood sampling will be contacted by the research team in coming weeks seeking their permission to use their blood serum for testing in this project. Because participants have to be selected randomly for the study to have any meaning, it is not possible for veterans to request testing at this time.