ronmental risks, this chapter and others in the report find no logical or scientific support for this assumption.
Environmental assessment of transgenic crops relies on risks associated with the transgenic variety being compared with multiple appropriate reference scenarios (ways to accomplish the same goal). For example, the risks associated with a transgenic herbicide-tolerant variety could be compared with risks of chemical weed management used on nontransgenic varieties, cultivation practices, crop rotations, and other approaches for weed management. This chapter ends by pointing out that there are a number of general approaches for formally examining a risk analysis to determine where errors could occur. These formal examinations could be helpful in assuring the rigor of the current system used for transgenic plants.