以中国变压器油和Aroclor1254中PCBs同系物组成为基础,计算中国PCBs产品同系物组成,结果显示中国PCBs产品主要以低氯代PCBs为主,CB-18含量最高为15.66%;三氯联苯含量最高,占56.48%,高氯代PCBs比例比国产变压器油略有增加,但远低于Aroclor1254。中国PCBs产品高氯代组分比例低于全球PCBs产品。中国PCBs产品中7种指示性PCBs占总PCBs的百分比为15.3%;三种类二噁瑛PCBs,CB-77、CB-105和CB-118,占总PCBs的2.6%。其百分含量TEQ值为9×10^-3%,稍高于Aroclor1242的7×10^-3%,但远低于Aroclor1254的3.4×10^-3%。中国大气中PCBs同族体分布与中国PCBs产品基本一致,中国表层土壤中PCBs中高氯代组分明显高于中国PCBs产品。
Congener and homologue profiles of polychlorinated biphenyls (PCBs) produced in China were analyzed by using PCBs in Chinese transformer oils and Aroclor 1254 as the two Chinese PCB products, #1 and #2 PCBs, respectively. The results show that low chlorinated biphenyls were the major components of the Chinese PCB prod- uct. The major CB congener in total PCBs was CB-18 (15.66%) and the major CB homologue was C13-CB (56.48%). The high chlorinated PCBs in total Chinese PCB product were a little higher than Chinese transformer oil but far lower than Arclor 1254 and global PCB product. Chinese PCB products consist only 15.3% of 7 indica- tor PCBs and 2.6% of dioxin-like PCBs. The total amount percentage TEQ in Chinese PCB products is approxi- mately 9 ×10^-3%, a little higher than that in Aroclor 1242 (7 ×10^-3% ), but much lower than that in Aroclor 1254 (3.4 ×10^-3% ). The results also revealed that while the homologue composition of PCB in Chinese air was consistent with that in Chinese PCB product, that in Chinese soil was higher for high chlorinated PCB homologue.