Effects of the Loss of Organophosphate Pesticides in the US: Opportunities and Needs to Improve IPM Programs

Abstract

insecticides, which they considered to be the highest risk category. The result has been that many OPs were (or are being) removed from the marketplace and others have restricted uses. Subsequent to FQPA, the regulatory focus on OPs has shifted again to consider their effects on farm workers and the environment, especially water quality. From a broad perspective, the loss of OP insecticides on larger cropping systems in the US has been relatively painless because many systems had already moved on to newer pesticide chemistries to deal with problems associated with worker safety, water quality, or insecticide resistance (Whalon et al., 1999). However, this generalization is not universally true and minor crops with little support for research on efficacy, residue degradation, or particularly problematic pests might be left with few or no viable replacement pesticides after the FQPA review is complete. The apple industry in the US is well known for its IPM programs and is one of the larger cropping systems currently in the final transition to the newer pesticide chemistries, making it a timely case study for the rest of this article. The slow transition to OP alternatives by the apple industry has been a result of the continued high efficacy of OPs against various key pests that feed directly on the fruit (e.g., codling moth (Cydia pomonella), plum curculio (Conotrachelus nenuphar), apple maggot (Rhagoletis pomonella), the relatively high cost of most OP alternatives, and the precarious stability of its IPM programs based on OPs.