squash, multiple genes are present for resistance to a number of viruses. This cotton case stands out because both genes have distinct commercial uses.

The environmental assessment and determination documents for this petition were relatively short. The assessment formally considered only two alternative actions: “no action,” which would mean refusal to grant nonregulated status, or a determination of a “finding of no significant impact,” which would result in complete deregulation. These alternatives contrast with other recent environmental assessments. For example, in the environmental assessment of a Bt corn petition that was also reviewed in 1997 (96-317-01p), three alternative actions are stated. The additional action listed is to “approve the petition with geographical limitation.” No explanation was given in this case study’s assessment about why only two options were considered.

Environmental Risks Considered by APHIS in Its Environmental Assessments and Determination Documents

Disease in the Transgenic Crop and Its Progeny Resulting from the Trans genes. Because the herbicide tolerance and Bt genes were inserted using Agrobacterium tumefaciens, and because a cauliflower mosaic virus 35S promotor and a chimeric 35S promotor were part of the inserted DNA, APHIS examined the potential for risk from these sequences that came from plant pest species. The potential for these sequences to result in risks was dismissed because the disease-causing genes were not present.

Potential Environmental Impacts. APHIS recognized the potential for transgenic cotton to cross with wild cottons in some parts of the continental United States but concluded that “none of the relatives of cotton in the United States show any definite weedy tendencies” (USDA 1997b). (APHIS acknowledged that judgment of weediness based on the 12 traits listed by Baker (1965) or subsequent modifications are “imperfect guides to weediness.” (The utility of Baker’s list as a regulatory guide is discussed at length in the previous case study and is not repeated here.) Furthermore, APHIS stated that gene flow to wild relatives would not be a problem because (1) “any potential effects of the trait would not significantly alter the weediness of the wild cotton; and (2) wild cotton populations have not been actively protected, but have in fact been, in some locations such as Florida, subject in the past to Federal eradication campaigns because they serve as potential hosts for the boll weevil” (USDA 1997b). The EPA, which has also reviewed transgenic Bt cotton, came to a different conclusion. EPA allowed the planting of cotton in all areas of the continental United States except southern Florida because of the presence



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