Gene-tailored organisms: soon ready for testing. But how are you going to keep them down on the farm?

Genetic engineers will soon be ready to field test a variety of gene-tailored organisms for use in farming. But those who regulate such tests in the United States and elsewhere are still not fully equipped to assess their environmental safety. Ecologists are in the ``discovery period'' in trying to develop standard tests for environmental safety or a set of safety assessment principles to be followed, warns Sheldon Krimsky, an environmental policy analyst at Tufts University. It took decades to develop such principles for testing the environmental safety of farm chemicals, he notes. ``No [comparable] set of canonical principles seems to be close [for genetically modified organisms] at this point,'' he says.

Professor Krimsky was one of several experts attending the annual meeting of the American Association for the Advancement of Science (AAAS) who warned that the world cannot afford to wait several decades to develop this knowledge.

Trevor Suslow, director of product research at Advanced Genetic Sciences in Oakland, Calif., explained that the few field tests conducted so far have not involved release of truly exotic organisms - that is, organisms whose genetic makeup combines genes from different species to a significant extent. Thus the safety assessments have been eased because researchers were dealing with the known ecology of well-known organisms. A wider base of knowledge must be developed quickly but methodically to deal with new organisms - especially microbes - whose ecology will not be as well known in advance, he said.

Dr. Suslow worked with Steven Lindow and associates at the University of California at Berkeley in testing the so-called ice-minus bacteria. This is a common bacterium that they slightly altered so that it tends to suppress frost formation when it lives on certain plants. After half a decade of litigation and extensive environmental safety research, they began testing the ice-minus microbe on potato and strawberry plants last year.

Suslow pointed out that, in this case, a slightly altered organism was returned to its native environment where it is unlikely to cause danger. The risk assessment was relatively easy. Yet it took a large investment of resources, not only by the researchers themselves but by the US Environmental Protection Agency.

Making the same point, Krimsky noted that EPA lacks the resources to deal with every new proposal for environmental release in similar depth. This, he said, emphasizes the urgency of developing standard safety tests and widely applicable safety principles.

One way to do this, said Arthur Kelman, a plant pathologist at the University of Wisconsin at Madison, is to work step by step from what is known. As an example, he cited the field test of Clemson University and the Monsanto Company under way in South Carolina.

As explained during the AAAS meeting by Clemson microbiologist Ellis Kline, this uses a bacterium slightly altered genetically to make it easy to detect. The experiment involves inoculating rows of wheat with the bacteria and then seeing how far the microbes move away into the general environment. This will begin to develop the kind of basic knowledge of bacterial dispersement needed for safety assessments.

Another way to speed development of this knowledge base is to restructure the education of genetic engineers and ecologists so that they understand each other's fields better than they do now and can work more closely together, according to Philip Regal, a biologist at the University of Minnesota.