Assessing Risk

As researchers use ever more sophisticated technology to create a growing list of drugs, vaccines, foods, and devices, potential risks stalk the process. With print and electronic media prodding them along, scientists, policymakers, business people, and the public have to consider the downside of inventions as well as the benefits. Headlines continually trumpet health risks--fluoridation caught the public's eye in the 1950s with stories that the procedure could rot teeth and cause cancer. Today's headlines question whether cholesterol-fighting drugs called statins increase the incidence of heart attacks and whether cyclooxygenase-2 inhibitors put arthritis patients at greater risk of the muscle-wasting disease rhabdomyolysis. Should millions of people taking these pharmaceuticals stop treatment? That depends on how much the possible side effects outweigh the drugs' benefits. When it comes to risk, biotechnology and genetically modified (GM) foods are no stranger to controversy. Do taco chips made from genetically modified corn really cause immune reactions, from hives to anaphylactic shock? Will pollen from GM corn threaten non-target insects? Do GM plants endanger the environment by cross breeding with wild relatives, thereby spawning superweeds? Most scientists would probably agree that answers to these questions, and therefore policy decisions based on them, require hard data. Reliable information in turn depends on the best available methods to assess risk. Harmless or Dangerous? With all the press that new drugs and genetically modified crops generate, governmental agencies that oversee these materials feel the heat. But federal agencies such as the Department of Agriculture, Food and Drug Administration, and Environmental Protection Agency largely rely on safety data provided by companies and other parties pressing for new product approval. According to the Council for Agricultural Science and Technology, an Ames, Iowa, think tank that studies agriculture-related issues (www.cast-science.org), "results of assessments are sent to EPA, USDA, FDA and other regulatory bodies around the globe, who evaluate the data in determining whether a biotech product should ultimately be approved for marketing."1 Laboratory tests and field trials help determine nutritional value, toxicity, and potential ecological footprints. The Cartagena Protocol on Biosafety to the Convention on Biological Diversity (www.biodiv.org/biosafety), adopted in Montreal in January 2000, calls for risk assessment of new GM organisms "in a scientifically sound manner ... and taking into account recognized risk assessment techniques."2 Those assessments should be based "at a minimun, on scientific evidence [in part outlined in the protocol] in order to identify and evaluate the possible adverse effects of living organisms on the conservation and sustainable use of biological diversity, taking also into account risks to human health." According to a recent report from the United Nations Development Program (www.undp.org/hdr2001), "the potential benefits of change may be great and the costs of inertia significant" in adopting GM crops--but the institutional and regulatory capacity needed to manage the concurrent risks may be too demanding," especially for developing countries.3 The report calls for cost-benefit analyses of biotech products: "An approach to risk assessment that looked only at potential harms would be flawed. A full risk assessment needs to weigh the expected harms of a new technology against its expected benefits." With all this attention, it's fair to ask whether current information and risk assessment methods can do the job. Can agencies, as the Cartagena Protocol stipulates, "evaluate the likelihood and consequences of identified adverse effects being realized," which in essence defines risk? Two federal efforts aim to improve the chances for successful crop evaluation. USDA Program in Place USDA recently requested proposals for the 2001 cycle of its Biotechnology Risk Assessment Research Grants Program. The purpose of the program, approved in 1990 legislation and activated in 1992, is "to assist federal regulatory agencies in making science-based decisions about the effects of introducing into the environment GM organisms, including plants, microorganisms, ... and other animals excluding humans," according to the department's solicitation. Toward that goal, the program will spend $1.5 million this fiscal year on such subjects as: potential for recombination between plant viruses and plant-encoded viral transgenes potential for effects of introduced gene products such as Bt toxins on nontarget species (a protein toxin from Bacillus thuringiensis expressed in corn set off a furor over Monarch butterflies in April 20004) possible changes to managed or natural ecosystems from genetically modified organisms resistance to introduced gene products in target species such as chewing insects impact of GM organisms on biodiversity increased fitness in wild or weedy species as a result of transgene flow from modified organisms. possible combinatorial effects of multiple or 'stacked' genes in crops (e.g., for herbicide or disease resistance) new statistical and quantitative methods to assess risks associated with field testing of crops. C.S. Prakash, who headed the USDA program in 2000, thinks it's important to compare conventional and GM plants. Says Prakash, director of the Center for Plant Biotechnology Research at Tuskegee University in Alabama, "we must pursue gathering benchmark data on conventional crops and practices related to gene flow, biodiversity impact, and other critical issues, and then ask the question, 'how risky are GM crops in relation to what we know?' The whole StarLink episode could have been avoided if EPA knew that commingling is a common phenomenon in grain handling in the [United States]." The StarLink problem, in which a type of GM corn approved only for animal consumption found its way into human foods including taco chips,5 probably resulted more from poor risk management than actual assessment. The USDA program specifically excludes risk management research. International Flavor While USDA concentrates on domestic agricultural risks, the Agency for International Development, or USAID, recently launched a grant program to support research on environmental and biodiversity risks posed by agricultural biotechnology in developing countries. The agency hopes the research will, among other things, build risk assessment capacity abroad and assist regulatory bodies in foreign countries to make science-based decisions about introducing GM organisms into the environment. According to Josette Lewis, biotechnology adviser for USAID, this is a brand new program "that expands the scope of our activities." Adds Lewis, the agency "has been funding ag biotech for 10 years. We take seriously its impact on people. Given that history, we decided to fund assessment as part of our program." Congress authorized the effort but failed to fund it, so USAID scavenged money from two other programs to pay for $1.8 million in grants. Lewis sees a clear mandate for the agency: Most US research "is not applicable to developing countries," where environmental conditions, biodiversity and farming practices are different. Besides, "the [United States] is not the center of origin for many crop plants," she says. Unlike USDA, however, the new USAID program supports projects on risk management. Will Programs Work? Will new research really produce major insights to help mold public policy? Prakash, with a year's worth of experience at USDA under his belt, worries that scientists may not take the bait. "This is a dull area of science especially in food safety," he admits, because "transgenes do not move out of GM crops any more than regular genes, if at all. One must ask, are these changes unique?" So far, Prakash thinks the answer is no. Many scientists may not go into risk assessment for other, more pragmatic reasons. "The research would never reveal any surprises," says Prakash. "The lack of interesting results means very low interest within academic researchers. Negative results are rarely published, which wouldn't help much in tenure and promotion." Lewis is more optimistic. So far response to the USAID program has been great--"maybe too great," she muses. "We have far more requests for information than we can fund." Lewis hopes the program will meet demand by continuing for at least five years, depending on funds. Barry A. Palevitz (palevitz@dogwood.botany.uga.edu) is a contributing editor for The Scientist. References 1. Council for Agricultural Science and Technology, "Ecological impact assessment: many stakeholders aid in the process to assess potential environmental impact of biotech crops," Ames, IA, 2000. 2. Secretariat of the Convention on Biological Diversity, "Adoption of the Cartagena Protocol and interim arrangements," Montreal, 2000. 3. United Nations Development Program, "New technologies key to reducing world poverty," Human Development Report, 2001. 4. B.A. Palevitz, "Bt or not Bt:Transgenic corn vs. monarch butterlies," The Scientist, 13[12]:1, June 7, 1999. 5. K. Devine, "GM food debate gets spicy," The Scientist, 14[21]:10, Oct. 30, 2000.

Assessing Risk

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