The company’s scientists test the GM crop for allergens, toxins, and anti-nutrients (compounds that inhibit the absorption of nutrients) and this data is submitted to the FDA. If the levels are ‘substantially equivalent’ to the conventional plant, the GM plant is approved for commercial sale and consumption. The FDA grants Generally Recognized As Safe (GRAS) status to GM foods, which means that these foods do not undergo additional tests or analysis with the FDA, unless there is a claim of a nutritional or health benefit. The guidelines for the conduct of food safety assessment of foods derived from GM plants are available online3. The rationale for this approach is that because whole foods are complex mixtures of compounds, animal studies cannot be readily applied for toxicological assessment because if any toxicity were found, it would be difficult to pinpoint what part of the food caused the toxicity. A report by the USA General Accounting Office contains recommendations for enhancing the effectiveness of the FDA’s evaluation of GM foods, including randomly verifying submitted test data, and increasing the transparency of the safety evaluations4. This would also improve the public’s confidence in the safety of GM foods. It is apparently still deemed unfeasible by scientists and regulatory officials to monitor long-term health risks of GM foods, as there is no scientific evidence of such possible harm and such studies would be technically challenging.
Genetically modified food research. I forgot where I got it so I don't know the link.