Project Summary Special Projects – Method Development/Validation This project is a matrix extension single laboratory validation that will expand testing for chemical hazards (pesticides) into animal feed. IDALS has been using a modified multi-residue method, based on QuEChERS extraction coupled with high-performance liquid chromatography–tandem mass spectrometry (LC-MS/MS) for detecting residue levels of acid herbicides. The QuEChERS method has extraction and clean-up steps, which have been developed to be Quick, Easy, Cheap, Efficient, Rugged and Safe. Originally, the modified method was validated for plant matrices but since then has been successfully adapted for soil and swabs with reasonably high recovery rates. With the surge of importance of detecting herbicide residues in feed, IDALS proposes to extend the scope of this multi- residue pesticide method by conducting a matrix extension by executing a level two single laboratory validation for acid herbicides with animal feed. A method to detect the presence of pesticides in animal feeds will support FDA efforts to minimize foodborne exposure to hazardous chemicals for both animals and humans.