Norwegian University of Life Sciences, Department of Plant and Environmental Sciences, P.O. Box 5003, N-1432, Ås, Norway.
Sci Total Environ. 2011 Dec 1;410-411:136-45. doi: 10.1016/j.scitotenv.2011.09.008. Epub 2011 Oct 5.
The concentrations and bioaccumulation of persistent organic pollutants (POPs) were determined in four fish species from Lake Koka, Ethiopia, representing 2-3 levels in the food chain of the lake. Dichlorodiphenyltrichloroethanes (DDTs), endosulfans, polychlorinated biphenyls (PCBs) and chlorpyrifos were identified, with DDTs as the most predominant pesticide, with concentration ranging from 0.05 to 72.53ngg(-1) wet weight (ww). All fish tissue samples collected from different species of the lake contained residues of DDTs. The maximum level of DDTs was found in the fattiest, African sharptooth catfish (Clarias gariepinus) sampled from the lake, with a mean concentration of 15.15ngg(-1)ww. The significant (P<0.05) relationship between concentrations of DDTs and δ(15)N indicates that DDTs biomagnified in the food web of the lake. The 4,4'-DDE to 4,4'-DDT ratio in Oreochromis niloticus (0.6) and Cyprinus carpio (0.5) were below 1, indicating ongoing use of DDTs in the study area and recent exposure of these fish species.
在埃塞俄比亚科卡湖的四种鱼类中，测定了持久性有机污染物 (POPs) 的浓度和生物积累情况，这些鱼类代表了该湖食物链的 2-3 个层次。二氯二苯三氯乙烷 (DDTs)、硫丹、多氯联苯 (PCBs) 和毒死蜱被鉴定出来，其中 DDTs 是最主要的农药，浓度范围为 0.05 至 72.53ng/g 湿重 (ww)。从湖中不同鱼类采集的所有鱼组织样本都含有 DDTs 残留。在从湖中采集的最肥的非洲尖齿锯鳐 (Clarias gariepinus) 中发现了最高水平的 DDTs，其平均浓度为 15.15ng/g ww。DDTs 浓度与 δ(15)N 之间的显著 (P<0.05) 关系表明，DDTs 在湖中食物网中生物放大了。奥利亚罗非鱼 (Oreochromis niloticus) 和鲤鱼 (Cyprinus carpio) 中的 4,4'-DDE 与 4,4'-DDT 比值 (0.6) 和 (0.5) 低于 1，表明研究区域仍在使用 DDTs，这些鱼类最近也接触到了 DDTs。
