Genetically modified crops under fire in EU and U.S. - Environmental

Compositional Analysis of Genetically Modified (GM) Crops: Key Issues and Future Needs. Journal of Agricultural and Food Chemistry. Hoekenga, Srinivas...
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Genetically modified crops under fire in EU and U.S.

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esponding to rising consumer concerns, an international consortium of seven major food retailers led by the United Kingdom's Sainsbury's grocery store chain vowed in March to eliminate ingredients derived from genetically modified (GM) crops from all its own brand-name products. The move could bode trouble for U.S. farmers and processed food manufacturers because no attempt has been made in the United States to segregate GM crops from non-GM crops, making it difficult to distinguish between the two in the marketplace. "This issue is going to run and run mainly because we've had a lot of health scares in Europe on beef, eggs, chickens, and cheese, which [have] created an enormous instinctive distrust of food that is modified in different ways," said Sheila Gunn, a spokesperson for Healey & Baker, international real estate consultants based in London. The firm recently polled Europeans on their views of GM foods and found that 61% of the respondents would not buy them. Opposition to the biotechnology front has been heating up in the United States as well. The latest action came in February, when, in the wake of the failed

Almost all processed food purchased in the United States contains ingredients derived from genetically modified soybean, corn, and canola crops.

biosafety protocol talks in Cartagena, Columbia [ES&T, April 1999, p. 150A], a coalition of environmental groups and organic farmers filed a lawsuit against EPA charging that the agency violated the law in approving genetically altered plants containing genes that produce a natural insecticide called Bacillus thuringiensis (Bt). Two other lawsuits concerning genetic engineering have been filed against the U.S. Food and Drug Administration (FDA) over the past year, but this is the first one directed at a specific application of GM organisms, said Charles Margulis, a spokesperson

Genetically modified crops A high percentage of crops planted during the 1998 growing season included genetically modified varieties. (Numbers provided by the Biotechnology Industry Organization.)

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for Greenpeace, one of the lawsuit's primary plaintiffs. The actions taken against FDA involved the recombinant bovine growth hormone used to increase milk production in dairy cows and the labeling of foodstuffs containing GM ingredients. The European Union, which has been working to revise a 1990 directive on GM organisms, requires all foods containing ingredients produced from GM soybeans and maize to be labeled. The U.S. FDA, on the other hand, only requires labeling when the GM crops are not "substantially equivalent" to their traditionally bred counterparts. For example, if a new food contains an allergen that consumers would not expect to find in that food, labeling would be required. In the Bt case, the plaintiffs claim that EPA violated the federal Fungicide, Insecticide, and Rodenticide Act by registering a plant pesticide that will lead to the rapid development of insect resistance to the Bt toxin, which occurs naturally as a soil bacteria. Organic farmers use the natural version of the Bt insecticide selectively as a last-ditch pestcontrol option; however, the GM variety exposes insects to continuous massive doses of Bt throughout the growing season, according to the complaint summary filed in the U.S. District Court for the District of Columbia. And not only does the GM pesticide kill for longer periods of time, it also wreaks havoc on beneficial insects and other nontarget organisms, the plaintiffs maintain. "All entomologists agree that insect resistance will develop," Margulis said. "They only disagree on how quickly and what steps need to be taken to slow down the development of resistance." © 1999 American Chemical Socie

Because the case is under litigation, EPA declined to comment. The biotechnology industry stands by its products, however. Bt so far has been successfully engineered into corn, soybean, cotton, canola, and potato plants, eliminating the need for topical pesticide applications, some of which pose health and environmental risks if mishandled, said Val Giddings, vice president for food and agriculture with the Biotechnology Industry Organization. "Over the last three years, this

biological insect control technique has enabled cotton farmers to avoid spraying, by conservative estimates, 850,000 gallons of pesticide compounds that would've otherwise required extremely careful handling," Giddings said. "Similar numbers are in play for other crops like soybeans or corn." While the most widely planted GM crops have been developed for insect and herbicide tolerance, Giddings touted other benefits such as improved food processing traits and nutritional content; resis-

tance to adverse soil and weather conditions; and improved fruit ripening, texture, and flavor. Because of questions being raised in the scientific community, however, as to whether EPA, FDA, and the U.S. Department of Agriculture are adequately examining the potential risks and socioeconomic impacts of modifying crops for pesticide resistance, the National Research Council has begun an internal eightmonth study of the issue. —KRIS CHRISTEN

Researchers question statistical power of PCB cancer study The largest study to date of occupational exposure to polychlorinated biphenyls (PCBs) has found no significant increase in cancer deaths among exposed workers. But several experts said mat the study is still too small to be conclusive. The study's principal author, epidemiologist Renate Kimbrough contends that the results of mis and other human studies indicate no association between PCB exposure and cancer. But other experts familiar with the work say that because cancers linked to PCB exposure are rare, tiiis study is too small to reveal the carcinogenic effects of PCB exposure. "It lacks the statistical power to detect real increases," said Howard Frumkin, Chair of the Department of Environmental and Occupational Health, Rollins School of Public Health at Emory University. The study, published in the March Journal of Occupational and Environmental Medicine, was funded by General Electric (GE) Co. GE faces potential liabilities of hundreds of millions of dollars for cleaning up several rivers, including the Hudson River in New York {ES&T, Aug. 1998, p. 360A363A). For many years, company officials have contended that PCBs are not linked to cancer or other adverse human health effects. PCBs are listed as a probable human carcinogen by EPA, the National Institute for Occupational Safety and Health, and the International Agency for Research

Epidemiologist Renate Kimbrough reports that no significant increase in cancer deaths was found among workers exposed to PCBs at two General Electric capacitor factories. (Courtesy Renate Kimbrough, IEHR, Washington, DC)

on Cancer. The "probable" designation stems from the fact that numerous animal studies have shown mat PCB causes cancer in laboratory animals. But studies of humans have yielded inconsistent results, according to reviews conducted by the Agency for Toxic Substances and Disease Registry in 1992 and EPA in 1996. The new study focused on just over 7000 men and women who worked for more than 90 days in two GE capacitor factories in upstate New York from 1946 to 1977. They were divided into groups on the basis of estimates of their PCB exposure; meir medical histories were followed for more than 30 years. For the 1233 who died, causes of death were compared to national and regional averages. The study found that

353 workers died of cancer, which was less than the national and regional averages. In addition, highly exposed workers did not have higher rates of cancer. The study has two main problems, according to Frumkin—size and exposure assessment. Many of the people studied either worked for GE for a short time or had low exposure, so few cases of cancer were expected, Frumkin said. In addition, workers were classified as "highly exposed" on the basis of their jobs, not their PCB blood levels. If this classification is wrong, then the study could be biased, he said. The study was conducted by the Institute for Evaluating Health Risks (IEHR), an independent research group. In addition to the GE study, the IEHR reviewed all of the previous studies of capacitor plant workers, according to Kimbrough. "Taken together, the results of these studies could be due to chance because there is no consistent pattern," she said. Former EPA Assistant Administrator for Prevention, Pesticides, and Toxic Substances Lynn Goldman, who is now at the Johns Hopkins School of Public Health, said it is too early to determine the study's impact. "This study is a valuable part of the literature. But it is only that—one piece." Before it can be included as part of the body of evidence, it needs to be subjected to a scientific examination that is much more thorough than peer review, she said. —REBECCA RENNER

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