recent report from the National Academy of Sciences has helped clarify the risks posed to human health and the environment by the genetic manipulation of animals to produce food, medicines or other products. The report makes it clear that one issue of great concern to many consumers — whether genetically engineered foods are safe to eat or drink — is no great problem. The greater danger lies in the possibility that genetically modified fish or insects might escape into the environment and disrupt or wipe out existing species. These issues need to be vigorously addressed by federal regulators, whose jurisdiction and authority in such matters is often murky.

The report was commissioned by the Food and Drug Administration and prepared by a panel of experts convened by the academy, the nation's most prestigious scientific organization. The panel did not assess the potential benefits of animal biotechnology but rather focused on the risks and their relative importance.

The biggest worry was that genetically engineered insects, fish, shellfish or other mobile animals might escape and reproduce in the natural environment, to the detriment of their natural counterparts. The F.D.A. is already considering an application to market transgenic salmon whose genes have been altered to accelerate their growth. Should such supersalmon escape from fish farms into the natural environment, as most experts consider inevitable, they might compete more successfully for food and mates than wild salmon, driving the wild stocks into decline. That danger can be mitigated by rendering the supersalmon sterile and too fragile to flourish in the wild, but such modifications may not be foolproof. The F.D.A., which primarily regulates food and drugs, has little background in such environmental matters, so federal regulators will need to combine their powers and expertise to ensure prudent regulation.

Genetically modified foods — say, meat with more protein and less fat, or eggs with less cholesterol — seem to pose fewer problems. The panel expressed some concern that genetically modified foods might contain proteins that could trigger allergic reactions in a small percentage of people. The probability of such allergic reactions was deemed low but the impact on susceptible individuals could be comparable to allergic reactions to existing foods, which are sometimes severe. Such reactions might not show up until products are on the market. This may be a risk that has to be accepted if the nation wants genetically improved foods. Labeling such foods may be the best way to alert potentially susceptible individuals.

The panel has found no evidence yet that milk or meat from cloned cattle are unsafe and no reason to think they might become unsafe. That is potentially good news for the owners of hundreds of cloned cows and bulls who have been asked to wait for regulatory approval before marketing their products. Over all, the potential risks in eating genetically modified foods look small compared with the risks posed by salmonella, E. coli and other pathogens in the existing food supply.

The most troubling problem identified by the panel is the creaking patchwork of laws and regulatory agencies that are expected to deal with a fast-moving technology they are ill equipped to handle. Congress needs to step in and clarify the authority and responsibility for regulating the products of biotechnology.