Multiresidue analysis of organochlorine and pyrethroid pesticides in ground beef meat by gas chromatography-mass spectrometry

A multiresidue method was developed and optimized for the identification/quantification of organochlorine pesticides (OCPs) and pyrethroids (PYRs) in beef meat samples. Samples extraction was performed by an automated solvent extractor and the extracts were cleaned-up by a tandem-cartridge system consisting of an Extrelut NT3 combined with a Sep-Pack C18 cartridge and a florisil minicartridge. Analysis was finally carried out by gas chromatography coupled with quadrupole mass spectrometry (GC/MS). The performance of the method was investigated in terms of linearity, accuracy, precision, detection limit (LOD) and quantification limit (LOQ). Good linearity was obtained, with correlation coefficients (r2) higher than 0.98. Mean recoveries were found in the ranges 70-110 % and 84-99 % for the investigated OCPs and PYRs, respectively, with the exception of extremely volatile hexachlorobenzene (HCB). RSD% turned out to range from 2 to 15 %. LOQ values were in the range 0.005-0.1 mg/kg for either class of compounds. The method developed was successfully tested on 50 commercial beef meat samples from the market area of Rome (Italy), proving to be a useful tool in routine multiresidue analysis of OCPs and PYRs for monitoring purposes. None of the compounds of interest were observed above their respective LOQ.