酸奶中有机卤素污染物的分子活化分析

Molecular activation analysis for organo-halogen contaminants in yogurt

本研究采用分子活化分析、GC-MS 相结合的方法分别测定了产自北京、上海、天津、广州、石家庄的14 个品牌 18 种酸奶中的总卤素(TX)和可萃取有机卤素(EOX)、环境持久性可萃取有机卤素(EPOX)、有机氯杀虫剂(OCPs)和多氯联苯(PCBs)等有机卤素污染物。主要讨论了酸奶中有机卤素污染物的总量、化学种态及其分布。结果显示,酸奶中绝大部分卤素为水溶性极性化合物,EOCl 和 EPOCl 是酸奶中有机卤素污染物的主要存在形式,未知氯约占 EPOCl 的 96%;酸奶中 OCPs 的主要来源仍是六六六(HCHs)和滴滴涕(DDTs),而 PCB202、PCB103 和 PCB128 是酸奶中 PCBs 的主要来源。

The concentrations of total halogen (TX), extractable organo-halogen (EOX), extractable persistent organo-halogen (EPOX), organo-chlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in 18 different yogurt specimens of 14 brands from Beijing, Tianjin, Shanghai, Guangzhou and Shijiazhuang were determined by epithermal neutron activation analysis (ENAA), molecular activation analysis (MAA) and GC-Mass Spectrometry (GC-MS), respectively. The results indicated that the halogen in yogurt mainly existed as inorganic species and non-extractable organo-halogen compounds. About 1/3 to 1/4 of EOX was EPOX. Further, EOCl and EPOCl were the main organo-halogen species in yogurt. The average concentration of the unknown organo-chlorine was 96% of the EPOCl. HCHs and DDTs were still the main contaminants of OCPs in the yogurt of interest. Also, PCB202, PCB103 and PCB208 were the main contaminants of PCBs.