See also: Healthy Food Choices Videos Genetically Modified Foods & HealthEARTH TALK Dear EarthTalk: Is it true that some foods we buy contain genetically engineered ingredients known to cause health problems?
George Kaye, New York, NY First made available in the U.S. during the mid-1990s, genetically modified (GM) foods have become staples of American agriculture, though most consumers are unaware of this. According to the non-profit Pew Initiative on Food and Biotechnology, the majority of corn, soy and cotton grown by American farmers today are from seeds genetically engineered to repel pests without the need for spraying pesticides or herbicides. GM versions of canola, squash and papaya are also coming on strong in the U.S.
As is the case with so many scientific controversies, the jury is still out regarding the potential health effects of GM food products. But while conclusive results have been hard to come by, some of the few studies conducted on animals fed diets consisting of GM foods have generated some disturbing results.
In one study, potatoes engineered to contain an insect-repelling gene to improve agricultural yield caused intestinal damage in the test subjects--some lab mice. While the mice did not die from eating the altered food, lesions that formed in their digestive tracts gave researchers pause enough to recommend more thorough testing of the “transgenic potatoes” before marketing them to humans.
In another study, mice were fed so-called “Flavr Savr” Tomatoes--tomatoes developed in the early 90s by Calgene that were “optimized for flavor retention.” Similar lesions arose in the intestines of the mice, causing reviewers from the Food & Drug Administration (FDA) to conclude that “the data fall short of ‘a demonstration of safety’,” adding, “unresolved questions still remain.” Yet later, yielding to the pressure of industry lobbyists, the FDA not only approved the Flavr Savr for mass human consumption, but also claimed that all safety issues had been satisfactorily resolved.
According to Belinda Martineau, a Calgene researcher who later published the tell-all book, First Fruit: The Creation of the Flavr Savr Tomato and the Birth of Biotech Foods, when the Flavr Savr hit store shelves consumers were not particularly impressed with its taste. Also, farmers were coping with disease problems and low yields, the very problems the technology sought to address in the first place. Eventually the FlavrSavr--or “Franken tomato,” as some cynics dubbed it--was abandoned altogether.
Its legacy lives on, however. Many environmental advocates feel that the FDA’s nod on the Flavr Savr set the bar particularly low for approval of other GM foods that may or may not cause health problems. Further, it remains to be seen what effects these hybridized species might have on the environment at large, reason enough to delay the mass release of GM foods into the market until more is known.
Meanwhile, European countries have remained steadfast against allowing GM crops to be grown on their own farms for fear of widespread environmental contamination. And whether or not to allow GM food imports into Europe is a matter of great debate right now within the European Union.
 CONTACTS: Pew Initiative on Food and Biotechnology, www.pewagbiotech.org GOT AN ENVIRONMENTAL QUESTION? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881 USA; submit it at: www.emagazine.com/earthtalk/thisweek/; or e-mail: earthtalk@emagazine.com . | 
