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目的了解某市市售畜肉类食品中多氯联苯(PCBs)的污染水平。方法于2008年8—12月采集某市28件猪、牛、羊样品,参照美国国家环保局EPA1668A方法,利用索式抽提装置和FMS自动纯化系统分别对样品进行提取和净化,通过高分辨气相色谱-高分辨双聚焦磁式质谱仪(HRGC-HRMS)对样品中的多氯联苯进行检测分析,采用同位素稀释的定量内标法对样品中的12个二英类多氯联苯(dioxin-like PCBs)和6个指示性多氯联苯进行定性和定量分析。结果牛肉、猪肉、羊肉中的18个多氯联苯化合物总含量分别为1607.60、435.82、505.17pg/g脂肪。其中,二英类PCBs含量分别为456.19、46.37、77.50pg/g脂肪。指示性PCBs化合物含量分别为1151.41、389.45、427.67pg/g脂肪。牛肉、猪肉、羊肉样品多氯联苯毒性当量(TEQ)中位数值分别为0.84、0.15、0.28pg/g脂肪。三类样品多氯联苯的TEQ(中位数值)均低于欧盟的行动标准限量值。在所有样品中PCB118均是对总PCBs含量贡献最大的化合物单体,而PCB126则是对毒性当量贡献最大的化合物单体。结论在采集的28个样品中有6个样品超过了欧盟行动标准的限量值,说明该市市售畜肉类食品存在一定程度的污染,应该进行溯源研究和污染原因的排查,以保障食品安全。
Objective To understand the level of PCBs contamination in commercially available meat products in a city. Methods Samples of 28 pigs, cattle and sheep in a city were collected from August to December in 2008. According to the EPA EPA1668A method of the United States Environmental Protection Agency (EPA), samples were extracted and purified by the Soxhlet extraction device and the FMS automatic purification system respectively. Gas chromatography - high resolution dual confocal mass spectrometry (HRGC-HRMS) detection of PCBs in the sample analysis, the use of isotope dilution quantitative internal standard method in the sample of 12 two British-class PCBs dioxin-like PCBs) and six indicative PCBs for qualitative and quantitative analysis. Results The total contents of 18 PCBs in beef, pork and mutton were 1607.60, 435.82 and 505.17 pg / g, respectively. Among them, the two British PCBs content were 456.19,46.37,77.50pg / g fat. Indicative PCBs compound content were 1151.41,389.45,427.67pg / g fat. The median TEQ values of beef, pork and mutton samples were 0.84, 0.15 and 0.28 pg / g fat, respectively. The TEQ (median values) for all three PCB samples were below the European Union’s Action Standard limit values. PCB118 was the single most contributor to total PCBs content in all samples, while PCB 126 was the largest contributor to toxicity equivalents. Conclusion Six of the 28 samples collected surpassed the limits of the European Union’s action standards, indicating that there is a certain degree of contamination of commercially available meat products in the city. Traceability studies and investigation of the causes of pollution should be conducted to ensure food safety.