Genetically Modified Corn — Safe or Toxic?

Enlarge Image Image Gallery Corn is one of the most commonly genetically modified foods. PHOTO: ISTOCKPHOTO

Pick up a box of cereal or other packaged food at the grocery store, and chances are you’re looking at a genetically modified product. The Center for Food Safety, a nonprofit organization that seeks sustainable alternatives to harmful methods of food production technologies, estimates that more than 70 percent of the processed foods in U.S. grocery stores contain some genetically modified ingredients — mostly corn or soy. But, in most cases, these modified foods have received only limited testing.

For example, take the three genetically modified corn varieties already being sold by Monsanto that are the subject of new analysis by French scientists. Two of the varieties have been genetically modified to contain unique proteins designed to kill insects that eat them, and the third variety was engineered to tolerate Roundup, Monsanto’s best-selling herbicide. Foods containing this “modified” corn are now being eaten by people all around the world, but the French researchers contend that Monsanto’s studies do not prove the corns are safe to consume.

Under current U.S. law, corporations are not required to make industry-conducted studies public. But, in this case, thanks to a lawsuit and the involvement of European governments and Greenpeace attorneys, these studies were released for independent analysis by scientists not being paid by Monsanto.

The researchers, affiliated with the Committee for Independent Research and Information on Genetic Engineering (an independent, nonprofit association dedicated to studying the impacts of genetically modified organisms), published their detailed critique of the Monsanto studies in the International Journal of Biological Sciences (2009; 5:706-726). They concluded that the data — which Monsanto claimed proved the corn varieties were safe to eat — actually suggest potential kidney and liver problems resulting from consumption of all three modified corn varieties, as well as negative effects in the heart, adrenal glands and spleen. The findings confirm a 2007 report from the same researchers on a single variety of modified corn.

An Apple Is an Apple Is a Genetically Modified Apple?

The new report also concludes that the Monsanto rat-feeding studies were so small and so brief that they clearly lack sufficient statistical power to prove the corn varieties are safe. So, why did governments grant permission to farmers to grow this genetically modified corn? Back in 1992, the industry persuaded the Food and Drug Administration (FDA) to rule that their crops are “substantially equivalent” to traditionally bred crops. This assumption — that genetically modified foods pose no particular risk — has led to our current system of weak regulatory oversight.

According to the nonprofit Pew Initiative on Food and Biotechnology, a project designed to facilitate dialogue about the pros and cons of genetic modification, “No single statute and no single federal agency govern the regulation of agricultural biotechnology products.” And, compared with the battery of tests demanded of chemical pesticides (evaluation of chronic exposure, carcinogenicity, etc.), the testing requirements for genetically altered crops amount to little more than a polite suggestion.