Krümmel Eva M, Gregory-Eaves Irene, Macdonald Robie W, Kimpe Lynda E, Demers Marc J, Smol John P, Finney Bruce, Blais Jules M
Department of Biology, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario KiN 6N5, Canada.
Environ Sci Technol. 2005 Sep 15;39(18):7020-6. doi: 10.1021/es050657q.
Fourteen sediment cores were collected from 10 lakes spanning a large gradient of sockeye salmon returns (0-40 000 spawners km(-2)) in Alaska and British Columbia in 1995-98 and 2002/03. The cores were analyzed for 210Pb to determine sedimentation rates and focusing factors. Polychlorinated biphenyl (PCBs) concentrations in the surface sediments (0-2 cm) were highly correlated with the number of sockeye salmon returns to each nursery lake. For 2002/03, the correlation between PCB concentration and number of salmon spawners was best with no correction factors applied, but decreased considerably when corrected for sedimentation rates, and was improved again by correcting for sediment focusing. Although sigmaPCB concentrations were similar in 1995-98 and 2002/03, the congener patterns varied. Because salmon are the dominant source of PCBs for most of these lakes, variation in sediment congener pattern likely derives from variation in congener patterns carried by the salmon. Overall, total PCB input by salmon has remained relatively constant since 1995. Unlike temperate Great Lakes contaminant studies, the North American west-coast lakes dominated by salmon bio-transport showed no sign of recent decrease in PCBs.
1995年至1998年以及2002/03年期间，从阿拉斯加和不列颠哥伦比亚省的10个湖泊采集了14个沉积物岩芯，这些湖泊的红大马哈鱼回游量梯度很大（0至40000产卵鱼/平方公里）。对这些岩芯进行了210Pb分析，以确定沉积速率和聚焦因子。表层沉积物（0至2厘米）中的多氯联苯（PCBs）浓度与每个育幼湖的红大马哈鱼回游数量高度相关。对于2002/03年，在不应用校正因子的情况下，PCB浓度与鲑鱼产卵者数量之间的相关性最佳，但在对沉积速率进行校正后显著降低，而在对沉积物聚焦进行校正后又有所改善。尽管1995年至1998年和2002/03年期间的σPCB浓度相似，但同系物模式有所不同。由于鲑鱼是这些湖泊中大多数PCBs的主要来源，沉积物同系物模式的变化可能源于鲑鱼携带的同系物模式的变化。总体而言，自1995年以来，鲑鱼输入的总PCB量一直相对稳定。与温带五大湖污染物研究不同，以鲑鱼生物运输为主的北美西海岸湖泊没有显示出近期PCBs减少的迹象。
