Margaret Mellon, Ph.D., J.D.
Jane Rissler, Ph.D.
Union of Concerned Scientists
INTRODUCTION
In the decade and a half since the agricultural biotechnology industry in the United States staged its first field trials, federal and state governments and private corporations have spent billions of dollars on research, commercial development, and regulation. This paper focuses primarily on the environmental successes and failures of that investment and the implications of that experience for U.S. readiness to deal with the next generation of agricultural biotechnology products.
THE U.S. APPROACH TO THE
REGULATION OF BIOTECHNOLOGY PRODUCTS
GENETICALLY ENGINEERED CROPS ON THE MARKET IN THE UNITED STATES
ENVIRONMENTAL IMPACTS OF ENGINEERED CROPS
Monarch butterflies: a near miss
Resistant pests
Research on environmental risks
HUMAN HEALTH ISSUES
SUMMARY
THE U.S. APPROACH TO THE REGULATION OF BIOTECHNOLOGY PRODUCTS
In the United States, the nascent agricultural industry emerged in the early 1980s—a product of two decades of dramatic advances in molecular biology research. As it became clear that the industry was contemplating a broad variety of products, including many that would be used out of doors, the Reagan administration began to grapple with questions of regulatory oversight. Even though it tended to resist regulation as a general matter, the Reagan administration eventually decided to fashion a new "regulatory framework" made up of old statutes. It explicitly rejected the option of new regulatory legislation targeted to biotechnology products, at least in part because administration policy was premised on the similarity of biotechnology to earlier reproductive technologies.
Although more palatable to biotechnology proponents than new legislation, the framework approach nevertheless presented daunting challenges. Many of the existing statutes were old and odd fits for the new technology and much work was required to twist them into shape. The statutes that became the centerpiece of the framework governed plant pests, drugs, food, new chemicals, and pesticides.
In 1986, the Reagan administration formally published a description of the biotechnology regulatory framework.1 Under it, three agencies—the United States Department of Agriculture (USDA), the Environmental Protection Agency (EPA), and the Food and Drug Administration (FDA)—were given the task of adapting existing statutes to govern the new technology. Beginning in 1987 and continuing to the present, the agencies have promulgated a number of new rules and regulations. Overall, the process has created a weak, often contorted, patchwork of regulations. For example, the current framework gives FDA authority to regulate genetically engineered fish under federal drug laws.2
Notably, central elements of the system are voluntary. For example, the FDA oversees genetically modified foods under a largely voluntary consultation program in which companies decide whether or not to consult on safety matters and what data, if any, to submit.3 The agency does not subject engineered foods to the rigorous safety reviews required for substances considered food additives. The end of a consultation is marked, not by an FDA approval, but by the agency's statement that the company has found the engineered crop to be as safe as non-engineered versions and that the agency has no further questions.4
At the USDA, all genetically modified crops are regulated as potential "plant pests." Under the regulations, companies are allowed to sell new crops, without restrictions, for planting on millions of acres of U.S. farmland once they overcome a low and scientifically inexplicable hurdle—a showing that engineered crops are not plant pests.5
The EPA, among the federal agencies overseeing engineered crops, has developed the strongest regulations. However, the agency has authority over only a subset of biotech crops, those that can be characterized as pesticides, primarily the Bt crops.6
GENETICALLY ENGINEERED CROPS ON THE MARKET IN THE UNITED STATES
So far, more than 40 genetically modified crops are currently allowed in commerce in the United States.7 Two traits—herbicide tolerance (HT) and insect resistance (Bt) engineered into four commodity crops (corn, cotton, soybeans, and canola)—dominate the products that have succeeded on the marketplace. Monsanto's products are the most popular of these crops but three other companies—DuPont/Pioneer, Syngenta, and Dow/Mycogen—also market them.
Two virus-resistant crops, papaya and squash, are currently planted on small acreage (fewer than 7,000 acres) in the United States.8 In addition, many of the products allowed on the market are not, as far as we know,9 actually being sold in commerce, including: the first commercial gentically modified food crop, the FlavrSavr tomato; other engineered tomatoes; altered-oil canola; several Bt crops (Bt potato and four Bt-corn products); HT sugar beet; and male-sterile chicory.
The HT and Bt crops, however, have proved to be very popular with U.S. farmers and have been widely adopted. Soybean growers appear to have been won over by the convenience of using glyphosate instead of older herbicides.10 Insect-resistant cotton is a favorite because it has led to substantial reductions in pesticide use for certain insects.11 Bt corn is popular because its use boosts yields in those fields with damaging levels of European corn borers.12
The impact of engineered crops on pesticide use is not a clear win for the environment. USDA data show, for example, that the adoption of glyphosate-resistant soybeans has led to a reduction in the number of herbicide acre-treatments13 but an increase in the overall amount of herbicides applied to soybeans (because glyphosate is a higher-dose herbicide compared with the pesticides it replaced).14
Bt corn has had little impact on overall corn insecticide use because growers typically have not used insecticides to control corn borers.15 Between 1991 and 2001, farmers consistently applied insecticides to approximately 33% of US corn acres.16
Bt cotton has dramatically reduced insecticide use in some states, most notably Arizona.17 However, the overall use of insecticides in cotton, as measured by acre-treatments shows little change, reflecting shifts in insect pests and adoption of more targeted pesticides.18
Other than the benefits to the technology companies (primarily Monsanto) and to farmers, there are few other benefits associated with Bt crops. None of the genetically modified food crops currently on the market, for example, offers benefits to consumers in terms of price, nutrition, or new products. Environmental benefits associated with reduced pesticide use, such as they are, are welcome, but are likely to be short lived due to the evolution of pest resistance (see below).
ENVIRONMENTAL IMPACTS OF ENGINEERED CROPS
As discussed in the 1996 UCS-authored report, The Ecological Risks of Engineered Crops, genetically modified crops pose six kinds of potential risks.19 First, the engineered crops themselves could become weeds, a broad term that covers plants with undesirable effects.20 Second, the crops might serve as conduits through which new genes move to wild plants, which could then become weeds. Third, crops engineered to produce viruses could facilitate the creation of new, more virulent or more widely spread viruses. Fourth, plants engineered to express potentially toxic substances could present risks to other organisms like birds or deer. Fifth, crops may initiate a perturbation that may have effects that ripple through an ecosystem in ways that are difficult to predict. Finally, the crops might threaten centers of crop diversity.
Although few problems of the sorts listed above would be expected to surface within the three-to-four-year time frame that the new crops have been in widespread use, the good news is that there have been no serious environmental impacts—certainly no catastrophes—associated with the use of engineered crops in the United States.
Of course, that does not mean that one can conclude that there have been no environmental effects. There may have been modest or subtle changes in animal or plant populations that are simply not dramatic enough or obviously enough connected to engineered crops to attract attention. Other than for insect resistance, there is no systematic monitoring underway in the United States to detect adverse effects of genetically modified crops.21 So much may be going on that we are simply not aware of.
There has been a notable near miss with the monarch butterfly, a situation that has much to teach about the weaknesses of the U.S. regulatory system.
Monarch butterflies: a near miss
In the spring of 2000, the U.S. media were abuzz with stories about a preliminary report in Nature indicating that pollen from Bt corn could kill the larvae of monarch butterflies in laboratory studies.22 Monarch butterflies are widely admired for their splashy coloring, their long—about 3,000 miles—migration, and their spectacular habit of overwintering massed together in trees in a few isolated spots in Mexico.23 Monarch larvae feed almost exclusively on milkweed, which grows in abandoned lots, along roadsides, and in and near corn fields. The migration takes the monarchs across the Midwest, the U.S. corn belt. If the pollen of Bt corn were indeed toxic to butterfly larvae under field conditions, the widespread planting of Bt corn could threaten an estimated 50% of the butterfly population.
The Nature study was published after several Bt-corn varieties had been approved by the EPA and over 20 million acres of Bt corn were planted in the United States. The big question was why the EPA had not addressed the threat to monarchs before approval of Bt corn. From a scientific standpoint, it is not surprising that a toxin aimed at the European corn borer (moth larvae) would also affect the larvae of the monarch butterfly. The tests required by the EPA prior to approval of Bt crops included a few trials in which Bt toxin was fed to honeybees and lacewings, among other organisms, but did not include tests on any non-pest moths and butterflies.24
The storm of publicity eventually forced the government to do a thorough risk assessment of the threat. To its credit, the USDA organized a workshop of scientists with expertise in the many areas needed to evaluate the monarch issue—from milkweed experts to molecular biologists—and asked them to generate a multi-disciplinary research program that would address the risks. It established a multi-stakeholder advisory committee to formulate a set of coordinated research projects to determine whether Bt corn is lethal to monarchs under field conditions. The department also provided funds—as did industry—to support the research. The results of the studies were published in five papers in September 2001 in the online version of the Proceedings of the National Academy of Sciences (PNAS).25
The major conclusion of the research was that only one of several Bt-corn varieties (Event 176) approved and planted for use in the United States produced high enough levels of Bt toxin in pollen to be lethal to butterfly larvae. Fortunately, that variety of genetically modified corn did not sell well and was not widely planted. Pollen from the two types of Bt corn which account for most of the Bt-corn acreage (Mon 810 and Bt 11) produce relatively low amounts of toxin and pose negligible risk to monarchs. Had Event 176 turned out to be popular, however, monarchs could have been in serious jeopardy.26 It was just a lucky break—not government vigilance—that protected the monarch butterfly.
Even though the PNAS studies added considerably to the understanding of the risks Bt corn poses to monarch butterflies, they did not completely resolve the issue. Some scientists have called into question a critical assumption on which the research was based—that monarchs eat only pollen and no other corn tissue.27 They point out that monarchs consume tissue from anthers—the pollen-producing parts of the corn flower—as well as pollen from Bt corn. Since anthers have been shown to contain considerably more toxin than pollen, these scientists believe that the PNAS studies based on pollen alone may seriously underestimate the toxin dose consumed by monarch larvae in corn fields.28 These concerns are bolstered by other studies showing that a mixture of Bt 11 pollen and anther fragments has a deleterious effect on monarch larvae29 and unpublished observations that anther fragments are commonly deposited on milkweed leaves in corn fields.30
If additional research were to confirm that the more-toxic anthers are indeed part of the monarch diet, this could be a serious blow to monarch butterflies.
The PNAS studies also did not address longer-term, nonlethal effects of Bt corn, that is, whether monarchs not killed after eating Bt corn might suffer other deleterious effects such as delayed development, impaired reproduction, and altered migration.
The monarch story illustrates serious weaknesses in the U.S. regulatory system. The kinds of studies that were published in PNAS should be done before products are released, not after. Yet, there has been no interest in adopting the monarch research model to subsequent EPA risk assessments. The recent application for the approval of a new Bt-corn variety directed against corn rootworms, for example, was not accompanied by research done in accordance with an agenda set by a multi-stakeholder group. EPA's risk assessment, which was heavily criticized,31 was done, like many others, under strong pressure to quickly approve products. Until risk assessment procedures improve, the public will not have confidence that another monarch-like threat will be detected before it's too late.
Resistant pests
Like many other pest-control products developed in the last 50 years, HT and Bt crops are likely to have a short life span. Already there are signs that the most popular HT crops—those resistant to the herbicide glyphosate (Roundup®)—will lose effectiveness as weeds become resistant to the herbicide. Scientists expect that Bt crops, too, will succumb to pests that evolve resistance to the Bt toxins. Concerns have also been raised recently about the possible evolution of a virus strain resistant to another genetically modified food crop—papaya engineered to withstand the papaya ringspot virus.32
Herbicide-resistant weeds. Just as antibiotics that emerged out of World War II medical research transformed human and veterinary medicine, synthetic pesticidal chemicals, also the result of war-time research, revolutionized U.S. agriculture. American growers swiftly adopted the miraculous chemicals—herbicides, insecticides, and fungicides—that killed the weeds, insects, and fungi that each year threatened to reduce yields. However, just as overuse of antibiotics led to antibiotic-resistant diseases in people and animals, overuse of pesticides on U.S. farms has meant that chemical after chemical has become useless as pests develop resistance. HT and Bt crops will likely suffer the same fate because they, too, are overused.
A few years ago, only one weed—ryegrass in Australia—was known to be resistant to glyphosate.33 In the last three growing seasons, however, weeds resistant to the herbicide have been reported in six states in the United States.34 Glyphosate-resistant horseweed, or mare's tail (Conyza canadensis), emerged in 2000 in Delaware in soybeans, in 2001 in Tennessee in cotton and soybeans, and in 2002 in Indiana, Maryland, New Jersey, and Ohio, also in soybeans.35 According to a New York Times article, resistant horseweed first showed up in Delaware fields planted several times with glyphosate-resistant soybeans.36 A University of Delaware weed scientist reported that the problem weed had spread to 20,000 acres in the Delaware, Maryland, and Virginia peninsula and in southern New Jersey by the end of the 2002 growing season while in Tennessee, it is reported to affect 500,000 acres.37
Even in areas where resistant weeds have not been reported, scientists are seeing shifts in dominant weed species that may be due to heavy use of glyphosate in engineered crops. For example, University of Illinois specialists suggest that increases in eastern black nightshade in Illinois soybean fields may be a result of widespread adoption of the glyphosate-resistant crop and the concomitant use of the herbicide in the state.38 Similarly, weed scientists in Iowa are finding populations of water hemp that survive spraying in fields of glyphosate-resistant soybean.39
To deal with the resistant weeds, companies are recommending a number of steps, including reducing the use of glyphosate-resistant crops and tank mixing glyphosate with some of the older, more toxic herbicides, such as paraquat.40
Bt-resistant insect pests. As Monsanto moved toward commercialization of Bt crops in the mid-1990s, scientists, environmental groups, and organic farmers began pressuring the EPA to take steps to delay the evolution of insect-pest resistance to Bt toxins. As a result, the EPA has imposed mandatory insect resistance management (IRM) plans on all Bt crops currently on the market.41 These IRM conditions constitute the strongest restrictions on any genetically modified crops in widespread use in the United States.
So far, there are no known cases of Bt-resistant pests emerging in response to plantings of Bt crops. The controls in place to help delay resistance consist primarily of refuges of non-Bt crops, though the refuges are smaller than many scientists would like.42
Recombinant papaya ringspot virus resistant to genetically modified papaya. By the early 1990s, scientists at Cornell University and the University of Hawaii had successfully engineered two papaya varieties to resist a Hawaiian strain of papaya ringspot virus (PRSV).43 To create two new papaya varieties, researchers inserted a coat-protein (CP) gene of a mutant form of the Hawaiian strain, following the lead of other scientists who had created plants resistant to virus attack by inserting a viral CP gene into the plant.44 In 1997, the federal government allowed commercial production of genetically modified papaya and by 1999 about 50% of the commercial papaya-growing area of Hawaii was planted with the engineered varieties.45 Subsequent research showed that naturally occurring non-Hawaiian virus isolates, as well as laboratory-generated recombinant strains of PRSV, could overcome the CP-mediated resistance and cause disease in both varieties, though with varying degrees of severity.46 The results with the recombinant lab strains raise concerns that resistance-breaking strains could arise in a non-lab environment, that is, papaya plantations, through recombination of Hawaiian strains with engineered papaya expressing the CP gene.47
Research on environmental risks
Despite chronic low-level funding for such studies, some research on the risks of genetically modified food crops has been done in the United States. These studies—as well as those done in other countries—point to the potential impacts of biotech products in the environment.48 The results of some of the most pertinent studies are summarized below.
Wild relatives gain advantage from Bt sunflower. Recent research from three U.S. universities shows that Bt genes that move into wild sunflowers from Bt-crop sunflowers confer substantial advantages on the wild relatives.49 Wild, weedy sunflowers, which readily hybridize with the crop, are common in areas of the United States where commercial sunflowers are grown. Compared with control plants at research plots in two states, the wild relatives receiving the Bt gene suffered significantly less damage from moth-type herbivorous insects. In addition, the insect-resistant wild relatives, probably as a result of reduced insect damage, produced more seeds than the wild relatives that had not received the Bt gene. This research is important because it supports the concern that an adverse effect of commercialization of Bt sunflowers would be wild, weedy sunflowers able to protect themselves from insect pests. In areas where insect pests are common, the Bt weeds would likely produce more seeds than non-Bt weeds, gradually increasing the hardiness of weedy populations.
Wild relatives gain advantage from engineered virus-resistant squash. In research similar to the sunflower study above, two Cornell University scientists found that virus-resistance genes which moved from a transgenic squash crop into wild relatives gave the relatives an advantage over others that had not received the gene.50 Under high pressure from virus disease, the virus-resistant wild relatives in the study produced more fruits and viable seeds than the non-virus-resistant control plants.
Bt crops indirectly affect beneficial insects. Swiss researchers have shown that green lacewings, beneficial predatory insects, suffered a higher death rate and delayed development when fed European corn borers which had eaten Bt corn compared with lacewings fed borers given non-Bt corn.51
HUMAN HEALTH ISSUES
No major human health problems have emerged in connection with genetically modified food crops, which have been consumed by significant numbers of U.S. consumers. As with environmental effects, only dramatic effects easily connected to engineered foods would likely have been detected. Because genetically modified foods are not labeled, people suffering ill effects would have difficulty relating them to consumption of engineered products.
It is important to remember that only in the last three or four years have herbicide- and insect-resistant soybeans and corn been planted on millions of U.S. acres and subsequently used in food processing.52
Over the past decade, food-safety experts have identified several potential problems that might arise as a result of engineering food crops, including the possibilities of introducing new toxins or allergens into previously safe foods, increasing toxins to dangerous levels in foods that typically produce harmless amounts, or diminishing a food's nutritional value.53 Problems like these would have to occur at very high levels within the U.S. population to attract the attention of regulators.
Among these potential impacts, scientists and regulators have been most worried about new allergens, and indeed, two events within the last decade legitimate that concern. First, a paper published in the New England Journal of Medicine (NEJM) in 1996 confirmed predictions that genetic engineering could transfer an allergen from a known allergenic food to another food.54 A few years earlier, scientists at Pioneer Hi-Bred seed company had successfully transferred a gene from Brazil nut into soybean to improve the grain crop's nutritional quality. Subsequent experiments showed that people allergic to Brazil nuts were similarly allergic to the transgenic soybean.55
Second, in the late 1990s, reports that a Bt-corn variety (StarLink) containing a potential allergen had illegally entered the food supply set off a tidal wave of controversy that ultimately reduced corn exports, frightened the food industry, and created widespread doubts about the strength of the U.S. regulatory framework.56 The EPA had not approved StarLink corn for human consumption because of scientific concerns that the Bt toxin might cause allergic reactions in some consumers. Rather, in 1998, the agency granted what has come to be known as a "split registration"—allowing StarLink to be used in animal feed but not human food.57 Two years later a coalition of public-interest groups tested products on retail food shelves and found StarLink corn in taco shells. Subsequently, the unapproved engineered corn was found in many products, forcing recalls and mill closures, halts in exports, and buybacks of contaminated corn. The StarLink incident, which richly illustrated the weaknesses of the U.S. regulatory system in the post-commercialization arena,58 continues to haunt U.S. farmers, food processors, and biotech companies. Among many other issues, it is casting a cloud over the emerging use of engineering to produce pharm crops by raising the specter of the contamination of the food supply by drugs.
SUMMARY
The American experience with genetically modified food crops, while encouraging, does not justify complacency about potential risks for several reasons. First, our experience is quite limited in important ways. Only two traits, herbicide and insect resistance, have been significant commercial successes. Crops with other traits have failed to achieve commercial success, have been held back by companies, or never made it through the research and development pipeline.
Second, the U.S. government provides very little post-market oversight of biotech foods. A recent report by the U.S.-based Pew Initiative on Food and Biotechnology (cited above) questions the ability of the government's weak monitoring and enforcement systems to detect unexpected human health and environmental problems and ensure compliance with regulatory requirements.59 In fact, the current "don't look, don't find" approach to monitoring is likely to detect only the most dramatic, highly visible effects.
Third, the scientific underpinnings of risk assessment and risk management are chronically and severely underfunded. Compared with the amount of U.S. taxpayer funds spent on biotech product development and related research, very little is earmarked for research on risks of engineered products. For example, in the 11-year period of 1992 to 2002, the USDA spent approximately $1.8 billion on biotechnology research and approximately $18 million on risk-related research.60 Many features of genetically modified food crops, for example, impacts of stacked genes and unresolved issues about Bt allergenicity, raise concerns that have simply not been adequately investigated.
Fourth, the diversity promised in future products and the new, more complex issues they are likely to raise are expected to severely challenge a regulatory system already straining under the comparatively light weight of today's products. This point is made by a trio of studies produced by the National Academy of Sciences (NAS). The first report, Genetically Modified Pest-Protected Plants: Science and Regulation, after reviewing the risks of crops engineered to produce insecticidal toxins and evaluating the EPA's program for regulating these crops, recommended that the agency strengthen its oversight.61
Two years later, a second report focused on the USDA and its regulation of engineered crops. The Environmental Effects of Transgenic Plants: the Scope and Adequacy of Regulation found serious shortcomings in the department's oversight of biotech products and recommended significant changes in its regulatory program.62 The report particularly noted that the USDA was ill prepared to protect against the risks of a new generation of biotech products nearing the end of the research and development pipeline.
Also in 2002, NAS published Animal Biotechnology: Science-Based Concerns, the academy's first report devoted solely to animals produced through modern biotechnology methods.63 That report found that the federal government's regulatory efforts have not kept pace with the advances in animal biotechnology research. As a result, they concluded that the current framework might be inadequate to oversee new animal biotech products as they move from laboratories towards commercialization.
Finally, the scientific evidence available to date, while encouraging, does not support the conclusion that genetically modified crops are intrinsically safe for health or the environment. The next generation of products—crops engineered to produce drugs and industrial chemicals64 and crops engineered to alter regulatory and metabolic pathways65—offer far more numerous traits and appear to be more obviously dangerous than Bt and herbicide-tolerant crops. It would be a serious misstep to overread the positive early experience with Bt and herbicide-tolerant crops and conclude that the weak regulation currently in place will suffice to control the risks of these and other new crops.
References
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2. Matheson, J. 1999. Will transgenic fish be the first ag-biotech food-producing animals? FDA Center for Veterinary Medicine, FDA Veterinarian, May/June. Vol. XIV, No. III. http://www.fda.gov/cvm/may99.html#2561.
3. Food and Drug Administration (FDA). 1992. Statement of policy: foods derived from new plant varieties. Federal Register 57: 22984-23005.
Gurian-Sherman, D. 2003. Holes in the biotech safety net: FDA policy does not assure the safety of genetically engineered foods. Washington, D.C.: Center for Science in the Public Interest. http://www.cspinet.org/new/pdf/fda_report__final.pdf.
4. FDA web site on consultations with companies concerning GE foods: http://vm.cfsan.fda.gov/~lrd/biocon.html.
5. USDA Animal and Plant Health Inspection Services (APHIS). No date. What is the process by which APHIS deregulates genetically engineered organisms to allow for commercialization? http://permanent.access.gpo.gov/websites
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6. Environmental Protection Agency. 2001a. Regulations under the Federal Insecticide, Fungicide, and Rodenticide Act for plant-incorporated protectants (formerly plant pesticides). Federal Register 66: 37772-817. http://www.epa.gov/pesticides/biopesticides/pips/pip_rule.pdf. Environmental Protection Agency. 2003. EPA's regulation of biotechnology for use in pest management. Available at http://www.epa.gov/pesticides/biopesticides
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9. Companies are not required to tell the government whether or not they are selling products. Our information about products comes from newspapers, web sites, and similar sources.
10. Fernandez-Cornejo, J. and W.D. McBride. 2002. Adoption of Bioengineered Crops. USDA Economic Research Service, Agricultural Economic Report No. 810.
11. Fernandez-Cornejo and McBride.
12. Fernandez-Cornejo and McBride.
13. An acre-treatment is the number of acres treated multiplied by the number of pesticide treatments.
14. Fernandez-Cornejo and McBride.
15. Environmental Protection Agency. 2001b. Biopesticides Registration Action Document: Bacillus thuringiensis (Bt) Plant-Incorporated Protectants. Washington, D.C.: Office of Pesticides Program. http://www.epa.gov/oppbppd1/biopesticides/pips/bt_brad.htm.
16. Personal communication, Dr. Charles Benbrook, June 9, 2003.
17. Environmental Protection Agency, 2001b.
18. Personal communication, Dr. Charles Benbrook, June 9, 2003.
19. Rissler, J. and M. Mellon. 1996. The Ecological Risks of Engineered Crops. Cambridge, Mass.: MIT Press, 168 pp.
20. Under this approach, horseweed in a soybean field is a weed as would be kudzu that killed trees and bushes or a rice variety that decreased the usability of a pond ecosystem by ducks.
21. Taylor, M. and J. Tick. 2003. Post-Market Oversight of Biotech Foods: Is the Market Prepared? Washington, D.C.: Pew Initiative on Food and Biotechnology, 128 pp.
22. Losey, J.E., L.S. Rayor, and M.E. Carter. 1999. Transgenic pollen harms monarch larvae. Nature 399: 214.
23. See http://www.monarchwatch.org.
24. See, for example, Environmental Protection Agency. 1997. Pesticide fact sheet: Bacillus thuringiensis CryIA(b) delta endotoxin and the genetic material necessary for its production (plasmid vector pCIB4431) in corn. Washington, D.C.: Office of Pesticide Programs.
25. Hellmich, R.L., B.D. Siegfried, M.K. Sears, D.E. Stanley-Horn, M.J. Daniels, H.R. Mattila, T. Spencer, K.G. Bidne, and L.C. Lewis. 2001. Monarch larvae sensitivity to Bacillus thuringiensis-purified proteins and pollen. Proceedings National Academy of Sciences USA 98: 11925-30; published online 9/14/01.
Oberhauser, K.S, M.D. Prysby, H.R. Mattila, D.E. Stanley-Horn, M.K. Sears, G. Dively, E. Olson, J.M. Pleasants, W.-K.F. Lam, and R.L. Hellmich. 2001. Temporal and spatial overlap between monarch larvae and corn pollen. Proceedings National Academy of Sciences USA 98:11913-18; published online 9/14/01.
Pleasants, J.M., R.L. Hellmich, G.P. Dively, M.K. Sears, D.E. Stanley-Horn, H.R. Mattila, J.E. Foster, P. Clark, and G.D. Jones. 2001. Corn pollen deposition on milkweeds in and near cornfields. Proceedings National Academy of Sciences USA 98: 11919-24; published online 9/14/01.
Sears, M.K., R. L. Hellmich, D.E. Stanley-Horn, K.S. Oberhauser, J.M. Pleasants, H.R. Mattila, B.D. Siegfried, and G.P. Dively. 2001. Impact of Bt corn pollen on monarch butterfly populations: A risk assessment. Proceedings National Academy of Sciences USA 98: 11937-42; published online 9/14/01.
Stanley-Horn, D.E., G.P. Dively, R.L. Hellmich, H.R. Mattila, M.K. Sears, R. Rose, L.C.H. Jesse, J.E. Losey, J.J. Obrycki, and L. Lewis. 2001. Assessing the impact of Cry1Ab-expressing corn pollen on monarch butterfly larvae in field studies. Proceedings National Academy of Sciences USA 98: 11931-36; published online 9/14/01.
Zangerl, A.R., D. McKenna, C.L. Wraight, M. Carroll, P. Ficarello, R. Warner, and M.R. Berenbaum. 2001. Effects of exposure to event 176 Bacillus thuringiensis corn pollen on monarch and black swallowtail caterpillars under field conditions. Proceedings National Academy of Sciences USA 98: 11908-12; published online 9/14/01.
26. Syngenta, the company that created Event 176, allowed the product's pesticide registration to expire in 2001. EPA permitted the company to sell existing stocks of Event 176 corn through the 2003 growing season. (EPA, 2001b)
27. Obrycki, J.J., L.H. Jesse, K. Oberhauser, and J. Losey. 2001. Memorandum to EPA Office of Pesticide Programs concerning docket no. OPP-00678B. September 11.
28. Obrycki, et al.
29. Jesse, L.C.H. and J.J. Obrycki. 2000. Field deposition of Bt transgenic corn pollen: lethal effects on the monarch butterfly. Oecologia 125: 241-48.
30. Cited in Obrycki, et al.
31. FIFRA Scientific Advisory Panel. 2002. SAP meeting minutes on a set of scientific issues being considered by the EPA regarding: corn rootworm plant-incorporated protectant non-target insect and insect resistance management issues. EPA, Office of Pesticide Programs. http://www.epa.gov/scipoly/sap/2002/august/august2002final.pdf.
Union of Concerned Scientists and Environmental Defense. 2002. Comments to the Environmental Protection Agency on Monsanto's application to register MON 863 for control of corn rootworms. http://www.ucsusa.org/food_and_environment/
genetic_engineering/epa-rootworm-bt-corn-2002.html.
32. Chiang, C.-H., J.-J. Wang, F.-J. Jan, S.-D. Yeh, and D. Gonsalves. 2001. Comparative reactions of recombinant papaya ringspot viruses with chimeric coat protein (CP) genes and wild-type viruses on CP-transgenic papaya. Journal of General Virology, posted online July 27, 2001. Available at http://www.sgm.ac.uk/jgvdirect/17560/17560ft.htm.
33. Pratley, J., P. Saines, P. Eberbach, M. Incerti, and J. Broster. 1996. Glyphosate resistance in annual ryegrass, Proceedings of the 11th Conference, Grasslands Society of New South Wales, Wagga Wagga, p. 122. See http://www.weedscience.org/Case/Case.asp?ResistID=380.
34. Weed Science Society of America, North American Herbicide Resistance Action Committee, and Herbicide Resistance Action Committee web site: http://www.weedscience.org/Summary/UspeciesMOA.asp?lstMOAID=12.
35. Weed Science Society of America, et al.
36. Pollack, A. 2003. Widely used herbicide is losing resistance. New York Times, January 14.
37. Pollack.
38. Reichers, D. and B. Simmons. 2002. Eastern black nightshade: re-emergence of an old nightmare for soybean growers. University of Illinois Extension, Agronomy Day 2002. http://agronomyday.cropsci.uiuc.edu/
2002/e-black-nightshade/index.html.
39. Canon, S. 2001. Weeds developing resistance to widely used herbicide, some say. The Kansas City Star, August 29.
Hartzler, B. 2001. Water hemp and glyphosate. Iowa State University Weed Science Online. http://www.weeds.iastate.edu/mgmt/2001/
glyphosatewaterhemp.htm.
40. For example, see Syngenta's recommendation to use Gramoxone Max™ (paraquat) at http://www.syngentacropprotection-us.com/media/article.asp?article_id=216.
41. See, for example, EPA documents on resistance management requirements for Bt crops at http://www.epa.gov/oppbppd1/biopesticides
/ingredients/factsheets/factsheet_006484.htm and http://www.epa.gov/oppbppd1/biopesticides
/pips/bt_brad2/4-irm.pdf
42. Knight, J. 2003. Agency 'ignoring its advisers' over Bt maize. Nature 422: 5, March 6.
Powell, K. 2003. Concerns over refuge size for US EPA-approved Bt corn. Nature Biotechnology 21: 467-68, May.
Mellon, M. and J. Rissler, eds. 1998. Now or Never: Serious New Plans to Save a Natural Pest Control. Cambridge, Mass.: Union of Concerned Scientists, 149 pp.
43. Ferreira, S.A., K.Y. Pitz, R. Manshardt, F. Zee, M. Fitch, and D. Gonsalves. 2002. Virus coat protein transgenic papaya provides practical control of papaya ringspot virus in Hawaii. Plant Disease 86: 101-05.
44. Chiang, et al.
45. Ferreira, et al.
46. Chiang, et al.
47. Chiang, et al.
48. See, for example, Letourneau, D. and B. Burrows, eds. 2002. Genetically Engineered Organisms: Assessing Environmental and Human Health Effects. Boca Raton, Fla.: CRC Press, 438 pp.
49. Snow, A.A., D. Pilson, L.H. Rieseberg, M.J. Paulsen, N. Pleskac, M.R. Reagon, D.E. Wolf, and S.M. Selbo. 2003. A Bt transgene reduces herbivory and enhances fecundity in wild sunflowers. Ecological Applications 13: 279-86.
50. Fuchs, M. and D. Gonsalves. 1999. Risk assessment of gene flow from a virus-resistant transgenic squash into a wild relative. Pages 141-143 in Methods for Risk Assessment of Transgenic Plants, K. Ammann, Y. Jacot, V. Simonsen, and G. Kjellsson, eds. Basel: Birkhäuser Publishing Ltd.
51. Hilbeck, A., M. Baumgartner, P. Fried, and F. Bigler. 1998. Effects of transgenic Bacillus thuringiensis corn-fed prey on mortality and development time of immature Chrysoperla carnea (Neuroptera: Chrysopidae). Environmental Entomology 27: 480-87.
Hilbeck, A., W.J. Moar, M. Pusztai-Carey, A. Filippini, and F. Bigler. 1998. Toxicity of Bacillus thuringiensis Cry1Ab toxin to the predator Chrysoperla carnea (Neuroptera: Chrysopidae). Environmental Entomology 27: 1255-63.
52. The first commercial GE crop, the FlavrSavr tomato, though it entered the market in the mid-1990's, was not a success and was consumed by few people.
53. Food and Drug Administration, 1992.
54. Nordlee, J., S. Taylor, J. Townsend, L. Thomas, and R. Bush. 1996. Identification of a Brazil-nut allergen in transgenic soybeans. New England Journal of Medicine 334: 688-92.
55. Nordlee, et al.
56. Bucchini, L. and L. Goldman. 2002. Starlink corn: a risk analysis. Environmental Health Perspectives 110: 5-13.
Taylor and Tick.
57. Bucchini and Goldman.
58. Taylor and Tick.
59. Taylor and Tick.
60. See the USDA Biotechnology Risk Assessment Research Grants Program web site at http://www.csrees.usda.gov/funding/rfas/biotech_risk.html. At that site, one can total the grant awards each year. Because the amount available for grants each year is 1% of the USDA biotechnology research budget (as mandated by the U.S. Congress), it is possible, by multiplying the total grants money awarded times 100, to obtain the funds spent by the USDA annually on other biotechnology research. In 2003, the U.S. Congress raised the risk assessment research set-aside to 2%.
61. National Research Council. 2000. Genetically Modified Pest-Protected Plants: Science and Regulation. Washington, D.C.: National Academy Press, 261 pp.
62. National Research Council. 2002. Environmental Effects of Transgenic Plants: the Scope and Adequacy of Regulation. Washington, D.C.: National Academy Press, 320 pp.
63. National Research Council. 2002. Animal Biotechnology: Science-Based Concerns. Washington, D.C.: National Academy Press, 181 pp.
64. See, for example, a UCS paper—Pharm and Industrial Crops: the Next Wave of Agricultural Biotechnology—available at http://www.ucsusa.org/food_and_environment/genetic_engineering/pharm-and-industrial-crops.html.
65. Wolfenbarger, L., ed. 2002. Proceedings of a Workshop on Criteria for Field Testing of Plants with Engineered Regulatory, Metabolic and Signaling Pathways, June 3-4, 2002. Blacksburg, Va.: Information Systems for Biotechnology, Virginia Polytechnic Institute and State University, 99 pp. Available at http://www.isb.vt.edu.
Paper presented by Margaret Mellon at a conference, Genetically Modified Foods—the American Experience, sponsored by the Royal Veterinary and Agricultural University, Copenhagen, Denmark, June 12-13, 2003.
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