Biotech Crops: Rely on the Science

By Martina McGloughlin
June 14, 2000
The Washington Post

Opponents of biotech foods harbor visions of genetically modified crops escaping into the environment, creating "superweeds" that could have an advantage over other vegetation. This will not happen for a logical reason. The plants that researchers want to improve through biotechnology are crops that are well understood--corn, soybeans, wheat, rice, canola, etc. Plant breeders have been working with these crops for centuries, looking for other plants that might contribute desirable traits to the crops' genetic makeup and using techniques such as mutagenesis and wide-crosses to introduce these traits.

Breeders have found that, with rare exceptions, the crops do not successfully cross-breed with other plants in the environment, especially plants in crop-growing regions. There is no reason to believe that an agricultural plant with one new gene will suddenly be able to breed with plants in the wild. The U.S. Department of Agriculture is charged with ensuring that no plant pest is introduced into the environment, and it has authority to stop sale at any time if a plant is determined to have become a pest.

Opponents of biotech also imagine changes that could cause a safe food to suddenly be unsafe--for example a nonallergenic food becoming allergenic. Extensive studies give assurance that this will not happen. First, the genetic material to be introduced is fed to rodents at an extremely high dose. The material is also examined to see whether it has anything in common with known allergens.

Once the material has been introduced into a plant, the plant is studied to see if inserting the gene created a new allergen. Several generations of the plant are analyzed for any unexpected changes.

Extensive studies compare the improved plant with a conventionally bred counterpart. Levels of protein, fat, fiber, starch, amino acids, fatty acids, ash and sugar are all compared with levels in the conventional plant. Levels of anti-nutrients, natural toxicants or known allergens likewise are compared. Field studies compare many biological factors, including height, color, leaf orientation, roots, flowering, shape, strength and grain size. If inserting a new gene causes no change in all of the factors examined, the Food and Drug Administration can conclude with great assurance that the improved crop is substantially equivalent to and as safe as the conventional crop.

What about wildlife? If the improved plant performs a function formerly performed by a chemical pesticide, such as protecting corn or cotton from insects, the Environmental Protection Agency requires extensive studies to assess the safety to humans as well as non-target insects and other wildlife. The inserted genetic material is tested on a range of non-target insect species such as honeybees, green lacewings, ladybird beetles and earthworms. It is also fed to birds, fish and mammals. In addition, the Agriculture Department monitors all biotech crops in several years' worth of field trials to see whether actual plantings have any adverse effect on wildlife. Activists have alleged that regulators were surprised that insect-protected corn pollen had an adverse effect on Monarch butterflies. In truth, the EPA considered the fact that the corn, which is harmless to other wildlife, is intended to kill the larvae of lepidopteran insects (moths and butterflies). Before granting approval for the corn, the EPA evaluated whether or not the larvae of desirable species, which do not feed on corn, would be exposed. The agency evaluated the potential risk and concluded that the benefit of removing chemical insecticide from the environment outweighed the possibility that some butterflies might be exposed. After all the uproar--caused by a laboratory study in which Monarch larvae were forced to eat the pollen--it is now clear that butterfly larvae have very little exposure in the field. Actual field studies have borne out what the EPA projected more than four years ago.

In a recent report from the National Academy of Sciences on the safety and testing of foods derived from biotechnology, the consensus among the scientists was that no evidence exists that biotech foods are unsafe. The rigor of regulatory oversight and the potential of the technology was articulated in a House Science Committee report on agricultural biotechnology, which concluded not only that there is no significant difference between plant varieties created using agricultural biotechnology and similar plants created using traditional crossbreeding but also that biotechnology holds tremendous potential to provide safe and nutritious foods, to protect the environment and lower costs to consumers.

I agree with the NAS report that more awareness of the regulatory process is needed. Because without any doubt the biggest problem with our robust, logical, science-based regulatory system is that not enough people understand how it works. The real issue is ensuring that individuals have factual, science-based information so that they can make informed decisions.

The writer is director of the University of California at Davis's biotechnology program.

Reprinted with permission of the author