meant any hazard that could be identified was similar enough to other known environmental hazards that an existing risk assessment methodology could be found to assess the risk. In other words, a new kind of risk would require a new risk assessment methodology. Below the committee reviews the kinds of hazards that can be associated with transgenic crop plants. None of these kinds of hazards is unique to transgenic plants, and hence no new kinds of hazards are identified. However, with the long-term trend toward increased capacity to introduce complex novel traits into plants, the associated potential hazards and risks, while not different in kind, may nonetheless be novel. For example, widespread planting of Bt corn generated concerns over a new potential non-target hazard—that toxic Bt corn pollen could reduce monarch butterfly populations.

The 1989 NRC study also found that transgenic plants should pose risks no different from those modified by classical genetic methods for similar traits. Traits that are unfamiliar (i.e., traits for which there has been little or no prior experience) in a specific plant will require careful evaluation in small-scale field tests. A 2000 NRC (2000c) report amplifies these points. It specifically notes that the magnitude of risk varies on a product-by-product basis and does not depend on the genetic modification process. However, the NRC (1989) report points out that information about the process used to produce a genetically modified organism is important in understanding the characteristics of the end product (NRC 1989).

Finding 2.4: For purposes of decision support, risks must be assessed according to the organism, trait, and environment.

Finding 2.5: For purposes of decision support, the process of production should not enter into the risk assessment.

Finding 2.6: The transgenic process presents no new categories of risk compared to conventional methods of crop improvement, but specific traits introduced by either of the approaches can pose unique risks.

Risk Analysis for Creating Legitimacy

The way Americans think about the relationship between agriculture and environment has evolved over time. For example, there was a time when a farmer’s decision to shift from pasture to crop production would have been thought to be a purely personal economic decision, raising no public concern over environmental issues. Now people recognize that pastures provide habitat for native flora and fauna and, when properly



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