A rapid multi-class, multi-residue UHPLC-MS/MS method for the simultaneous determination of anticoagulant rodenticides, pesticides and veterinary medicines in wild animals, pets and livestock

Abstract

Pesticides, veterinary medicines and anticoagulant rodenticides are used globally and any adverse impact of their past, current and future use on the world's food, flora and fauna is assessed largely by our ability to detect, identify and quantify residues of the hundreds and thousands of different chemicals involved. An analytical strategy that combines QuEChERS based sample preparation and UHPLC-MS/MS (that incorporates polarity switching) has been developed and validated to allow the rapid and simultaneous determination of 159 multi-class pesticides, veterinary medicines, anticoagulant rodenticides and paracetamol in biological specimens from a variety of non-target vertebrate animals. The procedure covers residues in the linear range 0.0005–0.05 μg ml⁻¹ in liver (chicken), muscle tissue (chicken) and kidney (lamb) matrices (correlation coefficient R² was ≥0.99 for all analytes in each matrix). Mean recoveries complied with validation criteria which was set at 60–140% and CVs ≤ 20% for all analytes in each matrix with just a few exceptions. The limit of quantitation was determined as 3 μg kg⁻¹ for the nine anticoagulant rodenticides and 25 μg kg⁻¹ for all other compounds. The method has been successfully deployed in the investigation of hundreds of suspected poisoning incidents. This streamlined approach has dramatically reduced analysis turnaround times, solvent consumption and perhaps most importantly, continues to generate scientific evidence regarding the magnitude and scope of chemical exposure of non-target animals that serves to inform regulatory authorities accordingly.