Determination of Organochlorine Pesticides and Polychlorinated Biphenyls in Milk by QuEChERS-Gas Chromatography-Tandem Mass Spectrometry

A gas chromatography-tandem mass spectrometry (GC-MS/MS) method was developed for the analysis of organochlorine pesticides (OCP) and polychlorinated biphenyls (PCBs) in milk. Samples were pre-processed with 30% sulfuric acid-methanol, and then extracted with n-hexane. The supernatant extract was purified by a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction procedure, and the purified extract was detected by GC-MS/MS and quantified by the matrix standard calibration curve method. The results showed that all the target analytes displayed good linear relationships in the range of 5-200 μg/L with correlation coefficients more than 0.99. The limits of detection (LODs) of OCPs and PCBs ranged from 0.1 to 0.3 μg/kg. The average recoveries of OCPs and PCBs from spiked samples were in the ranges of 85.5%-115.2%, with relative standard deviations (RSDs) less than 10% (n = 6). In summary, the proposed method due to its simplicity, high accuracy and efficiency could be used for the rapid screening and quantitative analysis of organochlorine pesticide and polychlorinated biphenyls in milk. © 2018, China Food Publishing Company. All right reserved.