Abstract: A quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction coupled with gas chromatography-tandem mass spectrometry (GC-MS/MS) method was developed for the determination of 35 polychlorinated biphenyls (PCBs) in vegetables. The sample was extracted using a solid-phase extraction column and QuEChERS with ethyl acetate as the extraction solvent, and then the extract was dried with anhydrous magnesium sulfate and cleaned up with primary secondary amine (PSA)/graphitized carbon black solid-phase extraction cartridge before being analyzed by GC-MS/MS under the selective reaction monitoring (SRM) mode and quantified by internal standard method. The results showed that the calibration curves for all target analytes displayed good linear relationships over the concentration range of 10-1 000 μg/L, with correlations coefficients of more than 0.999. The limits of detection (LODs) were 0.65-18.12 ng/kg. The average recoveries of 35 compounds at three spiked levels of 0.01, 0.02 and 0.10 mg/kg ranged from 72.3% to 119.0%, with relative standard deviations of 0.4% to 9.8%. The simplicity, rapidity, sensitivity and accuracy of the method make it suitable for rapid detection of PCB residues in vegetables.

Key words: QuEChERS, gas chromatography-tandem mass spectrometry (GC-MS/MS), PCBs, vegetables