More than 500 scientists, including several Nobel prize winners, said Friday they fear the United States is moving toward "a biological arms race" and vowed not to help advance military biological research.

"Biological warfare is an outright perversion of our ultimate aims and goals. This is not what we went into science for," said Jane Koretz, a biophysicist from Rensselaer Polytechnic Institute in Troy, N.Y."Living organisms are qualitatively different from gunpowder, mustard gas and nuclear bombs. These agents, dangerous as they may be, do not grow and reproduce themselves," said Jonathan King, a molecular biology professor at Massachusetts Institute of Technology.

"An escalation is taking place that could lead to a biological arms race," King said.

The scientists signed a pledge, prepared by the Committee for Responsible Genetics, a Boston group, "not to engage knowingly in research and teaching that would further the development of chemical and biological warfare agents."

Among the signers were Nobel prize winners Christian Anfinsen, Salvador Luria and George Wald.

Although the Defense Department has conducted a "biological defense program" for years, funding has risen sharply during the Reagan administration - from $21 million in fiscal 1982 to about $60 million in fiscal 1988.

In 1972, the United States was among the nations signing a biological weapons disarmament treaty banning the research, development, stockpiling and use of biological weapons.

The U.S. military describes its current efforts involving biological agents as defensive in nature. Dissenting scientists say, however, that offensive and defensive capabilities cannot be separated because the research is identical.

"I would consider that we are in violation of the spirit of the treaty, if not the letter," King said.

The proposed reopening of Dugway Proving Ground in Utah to military tests of biological agents particularly concerned the scientists. Dugway was shut down when a nerve gas test went awry, killing hundreds of sheep.

The Defense Department says it wants to use the facility to test protective clothing and other devices designed to protect against biological agents. Pentagon officials have indicated that the tests, some involving the spraying of live organisms into the air, will use existing organisms, not genetically engineered microbes.