Quantitative determination and validation of 96 pesticides in cannabis by LC-MS/MS and GC-MS/MS

Canada has established a strict set of testing requirements for pesticides that are unauthorized for use on cannabis, currently holding the most extensive list of analytes in North America to date, listing minimum method performance limits rather than maximum allowable concentration limits. These requirements establish the need for validated analytical methods capable of quantifying pesticides and growth regulators in highly variable cannabis inflorescence prior to distribution and sale. We have developed quantitative LC-MS/MS and GC-MS/MS methods capable of quantifying the 96 pesticides unauthorized in Canada for use on cannabis in dried cannabis flower and hemp. Herein, we report the validation results for linearity, precision, within- and between-sample accuracy, recovery, ion suppression, and limits of quantitation in dried cannabis inflorescence. Accuracy is evaluated in 10 cultivars varying in major cannabinoid content as well as ground whole-plant hemp to demonstrate method performance over a range of sample types. Results of the application of the current method to six cannabis samples seized from illegal storefronts by the Ontario Provincial Police are also reported.