the environment. As discussed in Chapter 1, only a small minority of nonindigenous species is invasive (see Figure 2.1), but at present we are unable to predict ex ante which species will be invasive and which will not. Consequently, it is impossible to construct a scientifically justified regulatory trigger based on the actual risk of invasiveness.

APHIS asserts its regulatory authority over the importation of nonindigenous species under the Federal Plant Pest Act (FPPA). The vast majority of nonindigenous organisms introduced into the United States arrive inadvertently in commercial shipping or deliberately through the trade of living organisms (aquarium fish, pets, horticultural plants). There is also a small but significant possibility that nonindigenous species are brought into the country by people arriving in airplanes and ships. For these passengers, APHIS uses two triggers for additional oversight. If a passenger is carrying animal or plant products, including fruits, meats, and living plants and animals, APHIS inspectors may confiscate or quarantine such products. If a passenger has visited a farm, APHIS inspectors may confiscate or quarantine clothing. While these triggers have a risk-related basis, they are also process-based triggers. Merely visiting a farm does not imply that a passenger is carrying an invasive nonindigenous species. However, as long as there is information indicating that, on average, passengers that have visited farms have a higher probability of carrying such a species, the process of visiting a farm is a useful risk-based trigger. These processes can be logical, operational ways to identify a subset of potentially risk-inducing activities, that will trigger oversight at U.S. borders.

Finding 2.9: A logical scientific argument can be made without reference to conventional crops that all transgenic crops should enter into regulatory oversight.

FIGURE 2.1 Venn diagram illustrating that invasive species are a small subset of all possible nonindigenous species.



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