Multiresidue method for simultaneous analysis of aflatoxin M1, avermectins,organophosphate pesticides and milbemycin in milk by ultra-performance liquid chromatography coupled to tandem mass spectrometry

A method developed for the simultaneous analysis of aflatoxin M₁, abamectin, doramectin, eprinomectin, ivermectin, moxidectin, acephate, azinphos-ethyl, azinphos-methyl, diazinon, methamidophos, methidathion, mevinphos, pirimiphos-ethyl and pirimiphos-methyl in whole raw milk, based on the QuEChERS method for extraction and clean-up, with detection and quantification by ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) is described. The method was validated according to parameters of the Analytical Quality Assurance Manual from the Brazilian Ministry of Agriculture and Commission Decision 2002/657/EC, and proved suitable for analysis of these analytes within the proposed working range, with recovery values between 77% and 110%, a standard deviation lower than 20%, limits of detection between 0.05 and 0.99 µg l^?1, and limits of quantification between 0.15 and 1.98 µg l^?1. Samples from animals treated with abamectin, doramectin, ivermectin and diazinon were analysed by the validated method. Residues of aflatoxin M₁ were also found in field samples at levels below the established maximum residue limit.