Ricca Mark A, Keith Miles A, Anthony Robert G
U.S. Geological Survey, Western Ecological Research Center - Davis Field Station, 1 Shields Avenue, University of California, Davis, Davis, CA 95616, USA.
Sci Total Environ. 2008 Nov 15;406(1-2):308-23. doi: 10.1016/j.scitotenv.2008.06.030. Epub 2008 Aug 9.
Persistent organochlorine compounds and mercury (Hg) have been detected in numerous coastal organisms of the Aleutian archipelago of Alaska, yet sources of these contaminants are unclear. We collected glaucous-winged gulls, northern fulmars, and tufted puffins along a natural longitudinal gradient across the western and central Aleutian Islands (Buldir, Kiska, Amchitka, Adak), and an additional 8 seabird species representing different foraging and migratory guilds from Buldir Island to evaluate: 1) point source input from former military installations, 2) westward increases in contaminant concentrations suggestive of distant source input, and 3) effects of trophic status (delta15N) and carbon source (delta13C) on contaminant accumulation. Concentrations of Sigma polychlorinated biphenyls (PCBs) and most chlorinated pesticides in glaucous-winged gulls consistently exhibited a 'U'-shaped pattern of high levels at Buldir and the east side of Adak and low levels at Kiska and Amchitka. In contrast, concentrations of Sigma PCBs and chlorinated pesticides in northern fulmars and tufted puffins did not differ among islands. Hg concentrations increased westward in glaucous-winged gulls and were highest in northern fulmars from Buldir. Among species collected only at Buldir, Hg was notably elevated in pelagic cormorants, and relatively high Sigma PCBs were detected in black-legged kittiwakes. Concentrations of Sigma PCBs, dichlorodiphenyldichloroethylene (p,p' DDE), and Hg were positively correlated with delta15N across all seabird species, indicating biomagnification across trophic levels. The east side of Adak Island (a former military installation) was a likely point source of Sigma PCBs and p,p' DDE, particularly in glaucous-winged gulls. In contrast, elevated levels of these contaminants and Hg, along with PCB congener and chlorinated pesticide compositional patterns detected at Buldir Island indicated exposure from distant sources influenced by a combination of atmospheric-oceanic processes and the migratory movements of seabirds.
在阿拉斯加阿留申群岛的众多沿海生物中已检测到持久性有机氯化合物和汞（Hg），但这些污染物的来源尚不清楚。我们沿着阿留申群岛西部和中部（布尔迪尔岛、基斯卡岛、阿姆奇特卡岛、阿达克岛）的自然纵向梯度收集了灰翅鸥、厚嘴海鸦和簇羽海鹦，并从布尔迪尔岛收集了另外8种代表不同觅食和迁徙类群的海鸟物种，以评估：1）来自以前军事设施的点源输入；2）污染物浓度向西增加表明有远距离源输入；3）营养状态（δ15N）和碳源（δ13C）对污染物积累的影响。灰翅鸥体内多氯联苯（PCBs）总量和大多数氯代农药的浓度在布尔迪尔岛和阿达克岛东侧始终呈现出高水平的“U”形模式，而在基斯卡岛和阿姆奇特卡岛则为低水平。相比之下，厚嘴海鸦和簇羽海鹦体内PCBs总量和氯代农药的浓度在各岛屿之间没有差异。灰翅鸥体内的汞浓度向西增加，布尔迪尔岛的厚嘴海鸦体内汞浓度最高。在仅于布尔迪尔岛收集的物种中，远洋鸬鹚体内的汞含量显著升高，黑脚三趾鸥体内检测到相对较高的PCBs总量。在所有海鸟物种中，PCBs总量、二氯二苯二氯乙烯（p,p' DDE）和汞的浓度与δ15N呈正相关，表明污染物在营养级间存在生物放大作用。阿达克岛东侧（一个以前的军事设施）可能是PCBs总量和p,p' DDE的点源，尤其是在灰翅鸥体内。相比之下，布尔迪尔岛检测到的这些污染物和汞的含量升高，以及多氯联苯同系物和氯代农药的组成模式，表明受到远距离源的影响，这种影响是由大气 - 海洋过程和海鸟的迁徙活动共同作用造成的。
