Report Finds Biotech Foods Safe ... So Far

By Cat Lazaroff

WASHINGTON, DC, January 25, 2001 (ENS) - No long term health effects have been detected from the use of transgenic crops and genetically modified foods, says a report by the scientific council of the American Medical Association. The report also concludes that bioengineered foods are "substantially equivalent" to their conventional counterparts.

The report concludes that the risk of gene transfer from engineered foods to animals or to human cells "is generally acknowledged to be negligible, but one that cannot be completely discounted."


Tests of potato genetic material, or DNA, loaded onto an agarose gel, reveal the presence of an experimental gene (Photo by Ken Hackman, two photos courtesy Agricultural Research Service)
The American Medical Association (AMA) council set out to review the technology used to produce transgenic crops, the current regulatory framework for managing these new crops, possible human health effects and potential environmental impacts.

More than 40 varieties of transgenic crops have been approved for use in the U.S. during the last decade, most of them genetically modified to produce a pesticide called Bacillus thuringiensis (Bt). The Bt toxin attacks pests like the European corn borer, but laboratory studies suggest it may also be dangerous to the larvae of the monarch butterfly and other butterflies and moths.

The AMA report concludes that the harmful effects of Bt containing plants on species like the monarch butterfly have not been observed in the field. "Nevertheless, these and other possible environmental effects remain areas of concern," the report says.

Among the potential problems the report identifies is the possibility that insects and disease pathogens will develop resistance to the pesticides carried by engineered plants, like Bt crops. This "has not occurred to date," the report notes, but is still a risk.


Plant physiologist Ken Gross examines tomato fruit used in a genetic engineering research program (Photo by Keith Weller)
"Genetic modification of plants could potentially lead to detrimental consequences to the environment," the report warns. "Therefore, a broad based plan to study environmental issues should be instituted."

The council reviewed 11 reports on genetically modified (GM) crops issued over the last two years by various scientific and governmental bodies, as well as dozens of individual scientific articles.

"Crops and foods produced using recombinant DNA techniques have been available for fewer than 10 years and no long term effects have been detected to date," the council reported. "These foods are substantially equivalent to their conventional counterparts."

Critics of GM crops warn that in transferring traits from one plant to another, biotechnology could transfer allergy risks as well. Someone with a peanut allergy could have a fatal reaction to a plant engineered to carry a peanut protein, doctors warn.


Field of genetically modified corn (Photo courtesy Novartis)
The AMA council said that risk is real, but is not unique to GM crops.

"Genetic engineering is capable of introducing allergens into recipient plants, but the overall risks of introducing an allergen into the food supply are believed to be similar to or less than that associated with conventional breeding methods," the council concluded.

Problems could also arise if biotech companies transferred traits from antibiotics into crops, a practice the AMA report said "should be avoided if possible."

The AMA recommended that federal regulatory oversight of agricultural biotechnology continue to be science based and guided by the characteristics of the plant, its intended use and the environment into which it is to be introduced. The methods used to produce a crop - whether biotechnology or conventional means - should not guide regulatory decision, the AMA said.

The AMA concluded that special labeling of genetically modified foods is not scientifically justified, and that voluntary labeling, as proposed by the U.S. Food and Drug Administration, is without value unless it is accompanied by consumer education.


BT corn pollen has proven fatal to monarch butterfly larvae in laboratory tests (Photo by Kent Loeffler, courtesy Cornell University)
But the group recommends the development of a standardized system for assessing the safety of genetically modified foods. Other recommendations include the development of additional techniques for detecting and assessing unintended effects of GM crops, and continued research to detect any substantial changes in the nutrient content or possibility toxicity of GM foods.

Priority should be given to basic research in food allergies to help develop improved methods for identifying potential allergens, the AMA said.

Environmental research needs include field research into the impacts of pesticide carrying crops like Bt corn, to confirm or refute prior laboratory studies, the council said. More information is needed about the potential for engineered genes to cross over into other plant species including wild weed populations, and the impacts of these genes of the ability of weeds to resist herbicides.

Monitoring programs need to be developed to assess other potential ecological programs and the effectiveness of efforts to keep insects from developing resistance to pesticides, the council concluded.

A summary of the AMA's report is available at: