A gas chromatography-tandem mass spectrometry method was developed for simultaneous determination of 38 polychlorinated biphenyls (PCBs) in tea. Sample preparation was based on a dispersive solid phase extraction procedure through an extraction of target compounds. An appropriate amount of polyvinylpolypyrrolidone was directly added in tea extractions to effectively remove polyphenols, and then tea extracts were cleaned up with primary secondary amine, florisil and graphitised carbon black. The method was validated, and linearity with correlation coefficients higher than 0.99 was obtained. Satisfactory recoveries at 2, 10, 50, and 100 µg kg-1 ranged from 71% to 117% with a maximum relative standard deviation of 23%, except for PCB 81, 77, 126 and 169, of which recoveries were in the range of 32%-63%. Limits of quantitation for PCBs were 2 or 10 µg kg-1, which was set as the lowest validated and spiked level meeting the acceptable accuracy and precision.

中文翻译：

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气相色谱-串联质谱结合分散固相萃取法测定茶叶中的多氯联苯。

建立了一种气相色谱-串联质谱法，用于同时测定茶叶中的38种多氯联苯（PCBs）。样品制备基于通过萃取目标化合物的分散固相萃取程序。在茶提取物中直接添加适量的聚乙烯基聚吡咯烷酮以有效去除多酚，然后用伯仲胺，弗洛西尔和石墨化炭黑净化茶提取物。验证了该方法的有效性，并获得了相关系数大于0.99的线性关系。2、10、50和100 µg kg-1的回收率令人满意，范围从71％到117％，最大相对标准偏差为23％，但PCB 81、77、126和169不在此范围内占32％-63％。