Cengage Learning. Not for Reprint. Is genetically engineered food bad for you? Maybe. Maybe not. A nation of LAB RATS.

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1 A nation of LAB RATS. (safety regulating of genetically-engineered food products by Food and Drug Administration) Barbara Keeler. Is genetically engineered food bad for you? Maybe. Maybe not. If it's true that you are what you eat, now would be the time to start scrutinizing the fine print. Just five years after genetically engineered foods were quietly introduced into the marketplace, gene-manipulated soy, papaya, yellow-neck squash, canola, potatoes, tomatoes, and dairy and animal products are on the tables of consumers, with another hundred or so, including wheat, expected soon. According to most estimates, 60 to 70 percent of all processed foods contain genetically modified ingredients. But there is no fine print. Food regulations in the United States don't require segregation or labeling of genetically engineered products. The Food and Drug Administration presumes that genetically engineered foods are substantially the same as their unmodified counterparts. But Health Canada (the FDA's Canadian equivalent), the UN Food Safety Agency, and the United Kingdom's Ministry of Agriculture have all questioned the safety of certain genetically engineered foods, especially dairy products from cows treated with recombinant bovine growth hormone, or rbgh. Last year, the EU declined to approve Monsanto's Roundup Ready corn for human consumption because of concern about potential allergic reactions. Roundup Ready corn and soybeans are ubiquitous in the U.S. food supply, despite Monsanto's own study for the FDA, which revealed large differences in nutrients and allergens between its modified and unmodified soybeans. To understand the potential problems, you first have to understand the process by which geneticists hope to imbue a living organism with new characteristics, such as herbicide resistance. Scientists pluck a gene from another species (a "transgene") that carries the desired trait. But the transgene does not travel alone. It generally rides in on a "truck" of bacterial DNA, loaded with baggage and sometimes unsuspected stowaways. Even if the transgene comes from a related plant species, bacteria, virus, and antibiotic-resistant genes are usually packaged in as delivery systems, "on switches," or markers. Whether transgenes are introduced into a cell of a host plant using bacteria or a "gene gun" (a process in which gold or tungsten micro-particles are coated with transgenes and then fired into targeted cells or tissues), they cannot be directed to a specific location on the host chromosomes or even to a specific chromosome. Incor- Keeler, Barbara. A Nation of LAB RATS. in Sierra Magazine, July/August, Copyright (c) 2001 by Sierra Club. All rights reserved. Reproduced by permission.

2 poration into the host DNA is more or less a crapshoot, and only a small percentage of cells end up with the transgenes. To figure out what's ended up where, scientists link marker genes that are resistant to antibiotics or herbicides, then kill off all cells except those with the resistance markers and allow the transformed cells to grow into intact organisms. Voila, a pest-resistant zucchini. Well, maybe--and maybe things unexpected as well. Without segregation of genetically engineered products and post-market monitoring, the long-term impacts on human health of, for example, the cauliflower mosaic virus (a virus used to assist the process as a "promoter") are impossible to monitor. But we've already had warnings of genetic engineering's potential impact on antibiotics resistance, naturally occurring allergens, and healthy human cells, some of them from the FDA's own literature. For example: * The FDA warns of decreased effectiveness of antibiotics due to antibiotic-resistant marker genes incorporated into genetically modified organisms and their enzyme products. The UK Ministry of Agriculture cautions that antibiotic-resistant genes in modified corn could render useless eight powerful antibiotics used by doctors to fight fatal diseases. * According to the FDA, "many plants naturally produce a variety of compounds that are toxic to humans or alter food quality. Generally, these are present at levels that do not cause problems. Combining plant and animal species in genetic engineering may create new and much higher levels of these toxins." Corn and potatoes engineered to produce toxins that kill insects are already regulated by the EPA as pesticides. * The FDA also warns that genetic engineering could transfer new and unidentified proteins from one food into another, triggering allergic reactions: "Millions of Americans who are sensitive to allergens will have no way of identifying or protecting themselves from offending foods. Allergic reactions can cause more than a simple discomfort--they can result in lifethreatening anaphylactic shock." A study by the UK's York Nutritional Laboratory, Europe's leading specialist on food sensitivity, revealed a 50 percent increase in soy allergies in 1998, a period in which the percentage of genetically engineered beans in the total soy crop jumped dramatically. For the first time in 17 years of testing, soy ranked among the top ten allergenic foods. Soybeans naturally contain at least 16 proteins that can cause allergic reactions, and one was found in almost 30 percent higher concentrations in Monsanto's transgenic soybeans. Rats eating those soybeans experienced retarded growth, and cows showed altered fat levels in their milk. * Canadian and European authorities recommended against eating foods from cows treated with rbgh after finding evidence of potential cancer hazards: Rats absorbed the hormone and developed immunological reactions, thyroid cysts, and prostate abnormalities. Cow's milk contained elevated levels of the hormone IGF-1, linked by research to increased cancer risk in humans. Even so, some U.S. dairy farmers--primarily industrial-scale operations--still inject their cows with rbgh. As long as genetically engineered foods remain largely unregulated and products 2

3 unlabeled, the causes and effects of those abnormalities may remain a mystery. The only comprehensive experiments may be under way at your dinner table. 3

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5 Biotech on the Farm. Rodney W. Nichols Bad money, says Gresham s Law, drives good money out of circulation. Similarly, for biotechnology these days, hyperbole drives solid evidence out of public view. As a result, the enormous potential for progress in agriculture has been pushed into the shadows. I am neither a farmer nor a plant biologist. But I have been mulling over what the combatants say in the continuing, high-stakes quest for effective innovation in food production. The challenge is urgent: the world population will rise roughly 30 percent by 2020, and little new arable land is available. My conclusions are optimistic. Science and engineering are building the knowledge to feed more people more economically, and to sustain agriculture while improving the environment. Those outcomes will power global economic development. But genuine problems may emerge as biotechnology is widely applied, and I am concerned that nations may ignore proven mechanisms for managing such risks. Junk science, thinly veiled protectionist concerns and projections of distant dangers now bedevil public understanding of the options. Those developments, in turn, erode the public trust in scientific knowledge and politicize the evidence relevant to choices that must be made. Norman E. Borlaug, a pioneer of the green revolution and the winner of the 1970 Nobel Peace Price, has noted: "Genetic modification of crops is... just another step in humankind's deepening scientific journey... We cannot turn back the clock on agriculture," he adds, "and only use methods that were developed to feed a much smaller population." Biotechnology can improve crop productivity with reliable transgenic procedures; it can engineer plants with highly specific disease resistances; and it can help fulfill nutritional goals by adding vitamins, protein and vaccines. Developing nations can employ the new technology to assure their food security. What about the risks? Bonfires of suspicion in England and the rest of Europe about genetically engineered food have not been doused, despite the careful statements of a number of unimpeachable authorities. In May 1999 the London-based Nuffield Council on Bioethics concluded: "We have not been able to find any evidence of harm." Borlaug agress: "There has been no credible scientific evidence to suggest that eating transgenic agricultural products damage human health, or the environment." Gordon R. Conway, the president of the Rockefeller Foundation and an agricultural ecologist who is acutely aware of possible future difficulties, says: "On current evidence, we assess the potential benefits to the developing countries as greatly exceeding the likely risks." One kind of criticism leveled against agricultural biotechnology is particularly unnerving: As a powerful new technology, genetically modified crops may carry some Nichols, Rodney W. Biotech on the Farm in The Sciences, Jul/Aug, Copyright 2000 by The New York Academy of Sciences, All rights reserved. Reproduced by permission. 5

6 risk--say, the risk that they will accidentally give rise to superweeds. Hence--so the argument goes--no uses for the technology can be approved unless all possible future risks can be ruled out. But such a conclusion would take a precautionary principle to an absurd extreme, transforming intelligent risk management into an almost mindless and endless restraint. There is a middle ground. Wise observers such as Conway advocate a measured approach akin to the one adopted in developing new drugs: test extensively on a small scale for safety and effectiveness, and probe for unintended side effects. U.S. farmers, a traditionally cautious lot, have experimented with genetically modified seed on millions of acres of cotton, soybean and corn--and confirmed its advantages. Yet consumers in developed countries remain largely unconvinced, and environmental activists see unresolved questions. Why not let the research flourish and the technological advances unfold with evidence-based regulation? In a halting and demoralized way, the process continues. But the paths for innovators are bumpy. Research and development in biotechnology is expensive, and the industry is undergoing a shakeout. The legal framework governing biotechnology in many countries is not even in place, much less enforced. Intellectual property in the agricultural context is a culturally sensitive issue: crops are closely identified with a nation's land and biological heritage. Yet economic incentives are critical for inventors, firms and governments. For the sake of the stuff of life, is it too much to call for a pause in picketing and a renewal of reasoning? The future of agricultural biotechnology is only as bright as the depth, clarity and persuasiveness of the evidence of its benefits. This summer the New York Academy of Sciences begins an effort to help shape a prudent consensus on the issues confronting biotechnology. 6

7 Would you support the commercialization of genetically engineered foods? 1. What are some major arguments in support of genetically engineered foods? 2. What are some major arguments against genetically engineered foods? 3. What are transgenes and how can they be problematic? 4. What does the author of A Nation of Lab Rats believe needs to be done to alleviate the problems that genetically engineered foods may pose? 5. Do the advantages of genetically engineered foods outweigh their disadvantages? Why or why not? 7