Single-Laboratory Ruggedness Testing and Validation of a Modified QuEChERS Approach To Quantify 185 Pesticide Residues in Salmon by Liquid Chromatography– and Gas Chromatography–Tandem Mass Spectrometry

In this study, we successfully applied a previously modified version of the QuEChERS approach to quantify pesticide residues in samples of fresh salmon. Analysis was performed using a combination of liquid and gas chromatography–tandem mass spectrometry (LC-MS/MS and GC-MS/MS). The validated QuEChERS method used ethyl acetate for the extraction solvent and involved two freezing steps and a C18 dispersive solid phase extraction for removal of lipids. Of the 228 pesticides initially screened, only 185 passed the method validation criteria (103 on LC-MS/MS and 82 on GC-MS/MS). In a quantitative validation, acceptable performances were achieved with overall recoveries of 70–120% and