Inter-Regional Research Project Number 4

Inter-Regional Research Project Number 4 (usually abbreviated as the IR-4 Project) has been conducted since 1963 by the United States Department of Agriculture in coordination with the Environmental Protection Agency to assist in the collection of residue and efficacy data in support of the registration or reregistration of minor use pesticides and the determination of tolerances for residues of minor use chemicals in or on raw agricultural commodities. It is the primary program for establishing what pesticides are safe and effective for use on fruits, vegetables, ornamental plants, and other specialty crops in the United States. While most of the minor uses investigated are small enough that it is not profitable for private business to establish the acceptability of a pesticide for individual speciality crops, collectively the specialty crops covered by the project make up almost half of U.S. agricultural crop production and over $40 billion in sales.