A method was developed for the determination of PCBs in soil and tea by online gel permeation chromatography and gas chromatography tandem mass spectrometry(GPC-GC-MS-MS). The QuEChERS method was improved, the samples were extracted by acetonitrile, salted out by NaCl and dehydration by anhydrous MgSO4, and purification with C18, PSA and anhydrous MgSO4, finally the extracts were confirmed and quantified by GPC-GC-MS-MS with matrix standard curve. The results showed that the detection limits ranged from 0.10 to 0.25 μg/kg and 0.03 to 0.30 μg/kg (S/N=3) in soil and tea, respectively. Seven kinds of PCBs had a good linear relationship with the chromatographic peak area in the range of 20-300 μg/L, and the correlation coefficients for soil and tea sample matrix were 0.998 2-0.999 2, 0.998 6-0.999 5, respectively. The recoveries of soil and tea samples were 84.9%-107.3% and 82.7%-108.9%, respectively. The relative standard deviations of the determination results for soil and tea sample were 3.4%-7.3%, 3.1%-6.8%(n=6), respectively. The method is simple, efficient, accurate and adequate for the quantitative analysis and rapid screening of PCBs in soil and tea.%建立测定土壤和茶叶中多氯联苯(PCBs)的在线凝胶渗透色谱-气相色谱串联质谱法(GPC-GC-MS/MS).对QuEChERS前处理方法进行优化,采用乙腈提取,用NaCl盐析分层,无水硫酸镁除水后,经C18,PSA和无水硫酸镁净化,用GPC-GC-MS/MS结合基质标准曲线确证及定量.PCBs在土壤和茶叶中的检出限分别为0.10~0.25 μg/kg和0.03~0.30 μg/kg,7种PCBs在20~300 μg/L范围内与其色谱峰面积呈良好的线性关系,土壤和茶叶样品基质的线性相关系数分别为0.9982~0.9992和0.9986~0.9995.土壤和茶叶样品的加标回收率分别为84.9%~107.3%,82.7%~108.9%,测定结果的相对标准偏差分别为3.4%~7.3%,3.1%~6.8%(n=6).该方法简便、高效、准确,适合于土壤和茶叶样品中PCBs残留的定量分析和快速监测.
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