LIKE THE household products and cosmetics industries, the American military is actively researching new in vitro methods. Military personnel are exposed not only to irritants and toxins found in traditional munitions but to those used in manufacturing unusual chemical and biological agents. Even experimental compounds designed to protect soldiers against anything from mosquitoes to defoliants must be tested to see if they themselves are toxic.

Robert A. Finch, a research toxicologist with the Army Biomedical Research and Development Laboratory at Fort Dietrich, Md., says the military has traditionally used small mammals for toxicity testing but is developing a special BRDL laboratory that will emphasize in vitro methods.

In vitro tests may also help the Army identify environmental hazards that need to be cleaned up,, says Hank Gardner, a BRDL research biologist. A number of Army posts have been deemed federal Superfund sites, and Gardner says that by one estimate, about 30 percent of the contaminated sites contain "military unique materials," such as outdated chemical weapons.

The process of neutralizing the chemicals, he says, could generate potentially dangerous by-products. But improved testing may help predict the toxicity of byproducts, insuring better protection for cleanup crews and preventing further contamination of the site.