IF THEY ARE true, the recent reports suggesting that the Soviet Union has violated the terms of an international agreement banning the production of biological weapons cast the future of all arms-control efforts in serious doubt. The story, based on information from Soviet emigrants and other unspecified intelligence sources, alleges that last spring several hundred citizens of the closed city of Sverdlovsk died within hours of an accident that released deadly anthrax bacteria, presumably grown as biological warfare agents.

In 1969, President Nixon declared that the United States unilaterally and unconditionally renounced all forms of biological warfare -- the only action of that kind this country has ever taken. Six years later, the international convention prohibiting the development, production and stockpiling of biological weapons came into force. Relying on the widespread belief that, in the words of Franklin Roosevelt, "the use of such weapons has been outlawed by the general opinion of civilized mankind," the convention did not include specific requirements for verification of its terms.

Recognizing that it is much easier to develop new bacterial strains than it is to find a means to protect against them, and that bioilogical weapons would therefore be almost as dangerous to the user as to those they were used against, the United States and other parties to the convention believed that in this one case they could depend on the word of each participating nation. This has not been true for other types of weapons: disagreements over the means of verification continue to block agreement on a treaty banning chemical warfare.

The United States has already asked the Soviet government for the facts on what happened at Svedlovsk. The Soviets have reportedly responded that an outbreak did take place, but that it was a natural biological event having nothing to do with bacteriological weapons. While government officials will say only that they are "studying the response," it raises several serious questions. Anthrax can be caused either by contact with contaminated animal products (for instance, meat or wool) or by inhaling airborne bacterial spores. pThe former type can often be treated and does not cause immediate death, while the latter -- as is reported to have happened in Sverlovsk -- often causes death within hours. It is at least unlikely that a large number of anthrax spores, enough to kill several hundred people, would appear from natural causes in the middle of an industrial city.

The Soviet government may have a reasonable alternative explanation. If however, the terms of the biological warfare conviction has been violated, the repercussions could affect every other present or future arms-control proposal. rSome will argue -- with reason -- that no arms-control treaty can henceforth serve the national security unless its verification provisions are virtually perfect: a very difficult standard.

If it has any serious interest in arms control, the Soviet Union now owes the United States, and the rest of the world, the complete and convincing facts of what happened in Sverdlovsk.