In the past two weeks, scientists have reported research results in Nature and The New England Journal of Medicine that indicate such fears are not unfounded. In the first case, Danish scientists showed that genes were able to pass from field specimens of canola (oilseed rape) - which had been genetically modified to resist herbicides - to their weed relatives. The weeds consequently enjoyed resistance to the chemical designed to kill them. In the second instance, University of Nebraska scientists demonstrated that soybeans that had been protein-enhanced with genes from Brazil nuts also had unintentionally been transferred the potential to produce deadly allergic reactions in people sensitive to Brazil nuts. Although these soybeans are designed to feed animals more efficiently, such basic grains may enter the human chain directly and therefore pose a hazard.

Critics also continue to blast away at the use of bovine growth hormone (BGH) which threatens to eliminate small dairies that cannot compete in a world with more cheap milk.

Such tales of harm are balanced in part by more hopeful scenarios. Perhaps the most significant is the potential for more diverse and highly productive rices for Asian agriculture. With funding, coordination and encouragement from the New York-based Rockefeller Foundation International Rice Biotechnology Network, Chinese and other Asian scientists have worked with U.S. and European molecular and cell biologists to improve and diversify rice planting stocks. Biotechnology is also proving significant in the urgent rush to create blight-resistant potatoes. The fungus that precipitated the deadly plague of Irish potatoes 150 years ago has evolved into more virulent forms; scientists the world over are racing to contain it with resistant planting materials. Biotechnologies are also tools in the plant breeders' battles to contain the pests that destroy food and income in other grains and tubers that provide basic calories and rural livelihoods.

The simple lesson here is that biotechnologies and the new biological species and varieties modified by these techniques are not in themselves either good or bad. Their positive or negative value and social impact depend on the particular species and characteristics that are being modified and the social and environmental contexts into which they are introduced. Prospects for help and harm rest side by side. The outcome must be evaluated case by case according to species and characteristics being modified and the peoples and environments they aim to modify. Do producers or consumers need a particular product? What are its potential risks or costs versus benefits?

To ensure more favorable, less risky outcomes, we need the government and the people, in partnership with public and private-sector scientists, to support activities more energetically in four areas.

First, there needs to be sustained public funding for agricultural biotechnological research that can develop products to address complex human needs while anticipating and avoiding risks. Such research is being carried out increasingly in the private commercial sector that has less incentive to examine costs and needs as they pursue profit. The decline in National Science Foundation and National Institutes of Health funding must be reversed, and research that will be able to anticipate hazards as well as benefits must be encouraged.

Second, there needs to be sustained funding for regulation. The current downsizing of government bureaucracy means that oversight is waning. Understaffed agencies authorized to issue permits to release and test genetically-engineered organisms into the environment are unable to monitor the permits effectively.

Third, the private firms that perform much of the applied research and product development need to be influenced by public pressure, to test thoroughly for potential hazards and to make this information available to scientists and the public.

Fourth, the public can exert additional persuasion on commercial firms at this early point in the development of biotechnologically modified products by not buying products that, although not unhealthful, are really unnecessary, expensive to produce and aggressively marketed. One of the first visible products to emerge from genetic engineering, the Flav'r Sav'r tomato, may yet fail commercially not because it is dangerous but because the public does not want it. Consumer resistance by an informed public may prove to be decisive even where government wavering on principles of free enterprise or free trade may fail to influence research and product development.

Now is the time for scientists and the public to pressure government and private firms to move in these directions: before impartial investigation and regulation are gutted and rendered ineffectual by budget cuts, and before the "hype" by both protagonists for and detractors against agricultural biotechnology make reasoned and balanced evaluation of products on a case-by-case basis impossible.