Meador James P, Ernest Don W, Kagley Anna N
Northwest Fisheries Science Center, National Oceanic and Atmospheric Administration, 2725 Montlake Boulevard East, Seattle, WA 98112, USA.
Sci Total Environ. 2005 Mar 1;339(1-3):189-205. doi: 10.1016/j.scitotenv.2004.07.028.
Concentrations of three non-essential elements (cadmium (Cd), mercury (Hg), and lead (Pb)) were determined in sediment and fish from several locations in Alaska (AK) and California (CA) and used to examine differences in bioaccumulation within and between geographic locations. We analyzed tissue (liver, muscle, gill, and stomach contents) from white croaker (Genyonemus lineatus) and English sole (Pleuronectes vetulus) in California and flathead sole (Hippoglossoides elassodon) in Alaska, in addition to several species of invertebrates (mercury only). As found in previous work on arsenic (As) [Meador et al., 2004], Cd in fish liver exhibited a negative correlation with sediment concentrations. No such correlations were found for Hg and Pb when fish liver and sediment were compared; however, these metals did exhibit a positive relationship between liver and organic carbon normalized sediment concentrations, but only for the CA sites. Sediment concentrations of Hg at the AK sites were lower than those for the CA sites; however, AK invertebrates generally bioaccumulated more Hg than CA invertebrates. Conversely, Hg bioaccumulation was higher in CA fish. Even though ratios of total metal/acid volatile sulfides (AVS) in sediment were one to two orders of magnitude higher for the AK sites, bioaccumulation of these elements was much higher in fish from the CA sites. Bioaccumulation factors ([liver]/[sediment]) (BAFs) were highest at relatively clean sites (Bodega Bay and Monterey), indicating that elements were more bioavailable at these sites than from more contaminated locations. The observation of high BAFs for As in fish from Alaska and low BAFs for the California fish, but reversed for Cd, Hg, and Pb in this study, implies that differences in fish species are less important than the unique geochemical features at each site that control bioavailability and bioaccumulation and the potential sources for each element. Additionally, these data were also used to examine the metal depletion hypothesis, which describes the inverse relationship between elements and organic contaminants documented in some monitoring studies. Our results suggest that the enhanced bioavailability of the metals at some uncontaminated sites is the main determinant for the inverse correlation between metal and organic contaminants in tissue.
测定了阿拉斯加（AK）和加利福尼亚（CA）多个地点沉积物和鱼类中三种非必需元素（镉（Cd）、汞（Hg）和铅（Pb））的浓度，并用于研究地理位置内部和之间生物累积的差异。我们分析了加利福尼亚州白姑鱼（Genyonemus lineatus）和英国鲽（Pleuronectes vetulus）以及阿拉斯加州太平洋扁头鲽（Hippoglossoides elassodon）的组织（肝脏、肌肉、鳃和胃内容物），此外还分析了几种无脊椎动物（仅汞）。正如之前关于砷（As）的研究[Meador等人，2004年]所发现的那样，鱼肝中的Cd与沉积物浓度呈负相关。当比较鱼肝和沉积物中的Hg和Pb时，未发现此类相关性；然而，这些金属在肝脏和有机碳归一化沉积物浓度之间确实呈现正相关，但仅在加利福尼亚州的地点如此。阿拉斯加州地点的沉积物Hg浓度低于加利福尼亚州地点；然而，阿拉斯加州的无脊椎动物通常比加利福尼亚州的无脊椎动物生物累积更多的Hg。相反，加利福尼亚州鱼类中的Hg生物累积量更高。尽管阿拉斯加州地点沉积物中总金属/酸挥发性硫化物（AVS）的比率比加利福尼亚州地点高1至2个数量级，但这些元素在加利福尼亚州地点鱼类中的生物累积量要高得多。生物累积因子（[肝脏]/[沉积物]）（BAFs）在相对清洁的地点（博德加湾和蒙特雷）最高，这表明这些元素在这些地点比在污染更严重的地点更具生物可利用性。本研究中观察到阿拉斯加鱼类中As的BAFs高，加利福尼亚鱼类中As的BAFs低，但Cd、Hg和Pb的情况相反，这意味着鱼类物种差异不如每个地点控制生物可利用性和生物累积的独特地球化学特征以及每种元素的潜在来源重要。此外，这些数据还用于检验金属消耗假说，该假说描述了一些监测研究中记录的元素与有机污染物之间的反比关系。我们的结果表明，某些未受污染地点金属生物可利用性的增强是组织中金属与有机污染物反比关系的主要决定因素。
