Newly available data from USDA's Pesticide Data Program allow us to trace pesticide residues on fruits and vegetables to their sources among various uses. We show that pesticide residues come from four sources: on-farm pesticide use; post-harvest pesticide use; pesticide use on imported food; and canceled pesticides that persist in the environment. Post-harvest pesticides account for the largest share of residue detections. Farmers' pest control choices influence consumers' dietary intake of pesticides, but the way in which food is marketed and the history of pest management techniques used on farms may have a greater influence. For pesticides that U.S. farmers currently use, the data show the geographic sources of residues and the extent to which use contributes to dietary intake risks. This information could be used to target development of pest control alternatives more narrowly. However, research to develop on-farm pest control alternatives will not address all pesticide residue risks in consumers' diets.
