长江源头典型湖泊表层沉积物中多氯联苯残留状况

Residues of PCBs in the Lake Surface Sediments of Yangtze Headstream

选择地处长江源头典型湖泊之一的红枫湖为试区,对该水域的14个典型采样点表层沉积物中多氯联苯(PCBs)残留量进行了调研,以揭示长江源头典型湖泊中PCBs的残留现状,以及各种同系物在湖泊底质中的分布特征.结果表明:PCBs残留总量介于ND^87.7 ng/g之间,平均值在27.2 ng/g,主要以4~6氯联苯为主.按残留量均值从高到低的几种同系物依次是:PCB138>PCB153>PCB126>PCB180>PCB105;检出率较高的几种同系物依次是:PCB153>PCB138>PCB126>PCB180.PCBs含量具有明显的地域性,以花鱼洞大桥为界限,将湖分为南北两湖,PCBs总含量北湖明显高于南湖.初步认为工业污染和PCBs理化性质是造成百花湖底质中PCBs来源的主要原因.

Residues of PCBs in the lake surface sediments of Yangtze headstream were investigated. The results show that residues of ∑ PCBs ranged from tens to ND - 87.7 ng/g, with an average value of 27.2 ng/g. It is main constitute 4 - 6 chlorine biphenyls. According to the gross of rudimental from high to low is PCB138 〉 PCB153 〉 PCB126 〉 PCB180 〉 PCB105, the residue from high to low is PCB153 〉 PCB138 〉 PCB126 〉 PCB180 .The content of ∑PCBs has obvious region characteristic, take the HuaYu bridge as boundary, Hongfeng Lake is divided into the lake south and north lakes. The content of ∑ PCBs in north lakes is higher than orthlakes. Analyzing the origin of PCBs, we found the industry pollutes and coal burning are two are the main reason for the pollution in Hongfeng Lack.