Savannah River Ecology Laboratory, University of Georgia, P. O. Drawer E, Aiken, SC, 29802, USA,
Arch Environ Contam Toxicol. 2014 Apr;66(3):341-60. doi: 10.1007/s00244-013-9984-3. Epub 2014 Jan 3.
Extensive and critical evaluation can be required to assess contaminant bioaccumulation in large predatory fishes. Species differences in habitat use, resource use, and trophic level, often influenced by body form, can result in diverging contaminant bioaccumulation patterns. Moreover, the broad size ranges inherent with large-bodied fish provide opportunity for trophic and habitat shifts within species that can further influence contaminant exposure. We compared contaminant bioaccumulation in four fish species, as well as two herbivorous invertebrates, from a coal combustion waste contaminated stream. Muscle, liver, and gonad tissue were analyzed from fish stratified across the broadest size ranges available. Effects of trophic position (δ (15)N), carbon sources (δ (13)C), and body size varied among and within species. Mercury and cesium concentrations were lowest in the invertebrates and increased with trophic level both among and within fish species. Other elements, such as vanadium, cadmium, barium, nickel, and lead, had greater levels in herbivorous invertebrates than in fish muscle. Sequestration by the fish livers averted accumulation in muscle. Consequently, fish liver tissue appeared to be a more sensitive indicator of bioavailability, but exceptions existed. Despite liver sequestration, within fishes, muscle concentrations of many elements still tended to increase by trophic level. Notable variation within some species was observed. These results illustrate the utility of stable isotope data in exploring differences of bioaccumulation within taxa. Our analyses suggest a need for further evaluation of the underlying sources of this variability to better understand contaminant bioaccumulation in large predatory fishes.
评估大型掠食性鱼类中的污染物生物累积，可能需要进行广泛而严格的评估。生境利用、资源利用和营养级的物种差异，通常受体型影响，会导致污染物生物累积模式的差异。此外，大型鱼类固有的广泛体型范围为物种内的营养和生境转移提供了机会，这可以进一步影响污染物的暴露。我们比较了来自受煤燃烧废物污染的溪流的四种鱼类以及两种草食性无脊椎动物的污染物生物累积。对跨可用最宽体型范围分层的鱼类进行肌肉、肝脏和性腺组织分析。营养位置（δ(15)N）、碳源（δ(13)C）和体型的影响在物种间和物种内均有所不同。汞和铯浓度在无脊椎动物中最低，并且在鱼类和无脊椎动物中都随着营养水平的升高而增加。其他元素，如钒、镉、钡、镍和铅，在草食性无脊椎动物中的含量高于鱼类肌肉。鱼类肝脏对这些元素的蓄积作用阻止了它们在肌肉中的积累。因此，鱼类肝脏组织似乎是生物可利用性的更敏感指标，但也存在例外。尽管肝脏有蓄积作用，但在鱼类中，许多元素的肌肉浓度仍随营养水平的升高而增加。在某些物种中观察到明显的差异。这些结果说明了稳定同位素数据在探索分类群内生物累积差异方面的效用。我们的分析表明，需要进一步评估这种变异性的潜在来源，以更好地了解大型掠食性鱼类中的污染物生物累积。
