Genetically Modified Foods. Benefits and Risks. Regulations and Safety

Beneficial traits derived from GMO technology include resistance to insects or pathogens (agents of disease), herbicide tolerance, longer shelf life in the supermarket, drought resistance, ability to fix nitrogen, ability to manufacture under drugs or vaccines, and so forth.

However, because this technology recombines DNA from widely disparate organisms and overcomes natural boundaries of evolutionary genetics that have evolved to protect and ensure the integrity and stability of an organism's genomes, GMOs may pose significant risks to human health and the environment.

For instance, in insect-resistant genetically engineered plants, the pesticidal toxin is produced throughout the plant, including the parts eaten for food. Individuals may have allergic reactions to the GM protein product in a plant. Furthermore, transgenes can be transferred by wind, insect, or animal pollinators into non-GM and organic crops, as well as wild plants in the natural environment.

Insecticidal proteins that kill target insects may also be harmful to beneficial insects in the environment, as demonstrated by the mortality decline of monarch butterfly larvae fed Bt corn pollen. Another concern is that target insects develop resistance to transgenic toxins just as they do to agricultural pesticides.

Regulations and Safety. No laws have been passed in the United States to specifically regulate the safety of GM plants and animals. If a product is not regulated under current laws, the government has limited authority. The Food and Drug Administration (FDA) oversees food and feed safety following the principle of substantial equivalence, which means that newly introduced substances must be functionally similar to other proteins, fats, and carbohydrates commonly and safely consumed in the diet.

The FDA does not conduct independent testing or make judgments about the safety of any GM product. Determination of safety for any food or feed product is the full, voluntary responsibility of the company producing the product. Because GM foods contain novel proteins not previously in the human diet, and because a single amino acid change can mean the difference between a nutritious food and a poison, the question of whether the concept of substantial equivalence is adequate to ensure safety has been raised.

The United States Department of Agriculture (USDA) issues permits for companies to conduct field tests of GM crops. The Environmental Protection Agency (EPA) regulates plant protection trials and labeling of plants engineered to kill insects or tolerate weed-killing chemicals.

EPA safety guidelines for GMOs are based on the regulations for agricultural pesticides to prevent humans from consuming excessive amounts of a harmful toxin in food and to restrict release of harmful chemicals into the environment. There is a crucial distinction between a transgenic product manufactured within the plant and chemical pesticides that are externally applied.

An important consideration is the opportunity for transgenes to recombine with the DNA of other organisms in nature after a GM plant or animal is released into the environment. Escaped transgenes crossing with wild relatives of plants and animals could result in genetic swamping if the genes are rapidly incorporated into the wild populations.

This would lead to greatly accelerated loss of natural biodiversity (biological diversity as indicated by numbers of species of animals and plants). How rapidly and how far transgenes can move were graphically illustrated by the discovery of Bt insect-resistant genes in native varieties of cultivated corn in remote areas of southern Mexico, the heartland of corn biodiversity.

This is alarming because it is against the law to plant GM seed in Mexico where it could lead to contamination and loss of native genetic resources that plant breeders traditionally use in corn improvement. This international incident has demonstrated that issues of GMOs crossing restricted political boundaries, liability, clean-up of contaminated seed supplies, and biodiversity loss are not just theoretical concepts. There is an urgent need to address these issues in an international legal framework.