The International Consortium on Agricultural Biotechnology Research (ICABR)
Public Research for U.S. Biosafety Regulation of Transgenic Crops
David E. Ervin,Portland State University and Winrock International, Rick Welsh, Clarkson University,
Sandra S. Batie, Michigan State University, and
Chantal Line Carpentier, Commission for Environmental Cooperation
Environmental (biosafety) risks from transgenic crops are diverse: increased pesticide use; increased crop and weed resistance to pesticides; gene flow into related plant species; negative effects on nontarget organisms; and, reduced crop and ecosystem diversity. Emerging evidence suggests some of the risks are real. However, the quantity and quality of research on the environmental impacts of transgenic crops is not sufficient to address many of the pressing questions surrounding these risks. The private sector cannot be expected to address many biosafety concerns due to missing markets. Government and universities have not filled the biosafety knowledge deficit because of inadequate research funding and little participation by environmental scientists.
Our relative ignorance of the potential environmental effects of transgenic crops raises risks to the environment and to the future of the technology. The central message of this paper is that more and different public research is needed to implement a cost-effective biosafety program and capture the full potential social benefits of the technology. We draw on contemporary environmental science and the precautionary principle to identify the major elements of such a research program.
The environmental effects of a transgenic crop depend on the characteristics of the organism, the environmental system in which the crop is placed, the skill with which it is managed, and the biosafety regulations to shape its development and deployment. Studies estimate a 2-3 percent decrease in U.S. pesticide use, but the effects vary widely by crop, region and year. Increased future pesticide use due to the buildup of resistance to heavily used herbicides is a long-term ecological concern. Evidence of some resistance in weeds, such as waterhemp, velvetleaf, and horseweed, exists. Environmental risks of insect- and virus-resistant crops also are theorized, but not well documented with field data. Ecological scientists have little doubt that crop-to-wild and crop-to-crop gene flows will occur with transgenic crops, as they have for classically bred crops. They tend to be most concerned about potential fitness advantages of insect- and virus-resistant transgenes from crop-to-wild gene flow. Herbicide resistance is a concern in crop-to-crop gene flow. Some field evidence exists, such as volunteer canola resistant to three herbicides, and growing problems with controlling herbicide resistant volunteer canola in parts of Canada. Various impacts on non-target organisms have been documented, such as deleterious effects on beneficial insects, although insufficient field and ecosystem monitoring are available to assess the full risks. Finally, there is broad agreement that the broad adoption of transgenic crops will continue to narrow in situ crop genetic diversity.
U.S. Biosafety System
The U.S. biosafety regulatory system is hindered by a lack of environmental science and monitoring on the environmental effects of transgenic crops. The systems use of the concept of substantial equivalence to approve many transgenic crops often neglects direct tests of ecological safety. The absence of evidence of significant environmental risks should not be confused with evidence of absence of such risks after rigorous environmental evaluations. Four improvements to the biosafety system are recommended: (1) increase the roles for environmental scientists; (2) designate a lead environmental agency; (3) improve public and scientists access to ecological and environmental data from company biosafety trials; and (4) incorporate clear roles for social science in setting risk criteria and standards.
Developing Public Research for Biosafety
The small science base on the biosafety risks and the weaknesses in the U.S. regulatory system argue for a cautious approach to transgenic crop technologies. A cautious approach does not imply a moratorium on all transgenic crops. More and different public research is needed to assure the transgenic technology achieves its full potential in developing sustainable agricultural systems. If we are to take biosafety risks seriously, the research should be informed by modern environmental science principles that stress the interconnectedness of ecological systems, the essential roles of ecosystem services, nonlinear and threshold responses to accumulating stresses, and the need for global perspectives. Recent unexpected yield drag for Roundup Ready Soybeans during drought and infertile soil conditions illustrates the need for applying the principles.
The precautionary principle, which attempts to avoid type II errors of assuming no significant environmental risk exists when in fact it does, should inform the research with biosafety in mind. Under this principle, the higher the potential for error, the greater the precaution it prescribes in taking actions that put certain health and environmental safety values at risk. Thus, a principal objective of the research is to better characterise the type II error distribution. A biosafety system that focuses only on type I error (i.e., lost technology benefits) and ignores type II is a weak application of statistical theory.
Some elements of a new biosafety risk research program include: (1) longer term pesticide studies with more spatial disaggregation for ecological variations to capture possible cumulative or synergistic effects of multiple compounds; (2) ecosystem monitoring systems for more precise error definitions and decisions on controls, such as setting up refugia to slow the evolution of pest resistance; (3) potential gene flow problems for transgenic crop trait-weed complexes with high probability of outcrossing and ecological disruption; (4) deleterious effects on non-target organisms, such as beneficial insects; and (5) crop genetic diversity effects in general.
The needs to address the impacts on ecosystem diversity and long term ecosystem functioning are compelling. Alternatives, such as ecologically based pest management systems, should be researched. Most fundamentally, the alternatives and more complete assessments require a reorientation of agricultural research in ways that embed the lessons of evolutionary biology and ecological sciences. Viewing the plant as a production machine that can be brute-force reengineered for more efficiency is a poor analogy. Unanticipated and unintended resultsboth positive and negative-- can emerge from such engineering because plants are complex systems embedded in poorly understood, complex, and interacting ecosystems. The precautionary principle schools us to ask what those results could be and seek answers for how the negative ones can be minimized, mitigated, or avoided. Economics tells us that under existing incentives, much of this research will necessarily require a public role. Sociology informs us that differing interpretations and values between social actors will keep biosafety in the policy arena for the foreseeable future.