广东红海湾银杏齿喙鲸鲸脂中多氯联苯的分布特征及其毒性评价

Distribution characteristic and risk assessment of PCBs in blubber of Mesoplodon ginkgodens from Honghai Bay,Guangdong China

多氯联苯(PCBs)对生态环境的污染和对动物体的危害早已引起全球广泛关注,为了解PCBs在中国近岸海域哺乳动物体内的积累状况,本研究采用Agilent 6890N型气相色谱仪、63Ni放射源-μECD检测器测定了广东红海湾银杏齿喙鲸(Mesoplodon ginkgodens)鲸脂中PCBs的含量水平、组成特征,并对其进行毒性评价。本研究结果对于探讨PCBs的生物地球化学过程以及保护野生水生动物具有重要意义。结果表明,银杏齿喙鲸鲸脂中共检出43种PCBs同系物,PCBs总含量平均为4.4μg/g(湿重),属污染相对较轻水平。PCBs组成以PCB87为主,相对含量为19.5%;其次是PCB153(13.9%)。运用二噁英毒性当量因子(TEFs)评价银杏齿喙鲸鲸脂中PCBs的毒性,其毒性当量值(TEQs)为3862pg/g(湿重),与世界其他海域鲸豚TEQs值相比,本研究中的TEQs值相对较高,可能由于非邻位取代的PCB126(59%)和PCB169(40%)较高相对含量导致。鲸体中PCBs可能来自工业品中的Aroclor1254,推测中国沿海局部区域废弃的油漆桶、变电装置、电子设备的违章堆放和拆卸,可能是PCBs的主要来源。

The blubber of Mesoplodon ginkgodens was collected from Honghai Bay,Guangdong Province. The PCBs were determined by gas chromatograph equipped with capillary column DB-XLB（30 m×0.32 mm×0.50 μm）and ^63Ni micro electric capture detector. Forty three PCB congeners had been detected,and the mean content of total PCBs in the blubber was 4.4 μg/g,which was at the low level compared with those from other different regions in the world. The relative abundance of PCB87 was the highest in all of the PCB congeners,accounting for 19.5%,followed by PCB153,occupying 13.9%. The toxicity equivalent quantities（ TEQs）of PCBs in the blubber of this whale were 3 862 pg/g. Compared with TEQs in the other cetaceans from the different waters in the world,the TEQs of PCBs in the whale of this study were at relatively high level. The TEQs of non-ortho PCBs occupied 99% of total TEQs,PCB126 accounting for 59%,followed by PCB169,occupying 40%. The mean composition of PCBs in this whale were similar to the Acroclor1254 in industrial products,which might root in the illegal demolition and stacking of abandoned paint, transformer or electronic equipment.