Dauphin Island Sea Lab, 101 Bienville Blvd., Dauphin Island, AL 36528, USA.
Chemosphere. 2011 Mar;82(10):1393-400. doi: 10.1016/j.chemosphere.2010.11.070. Epub 2010 Dec 18.
Arsenic (As) and mercury (Hg) are among the most toxic metals/metalloids. The overall goal of this study was to investigate the bioaccumulation of these trace elements in Vallisneria neotropicalis, a key trophic species in aquatic environments. For this purpose, As and Hg concentrations were determined in sediments and natural populations of V. neotropicalis in sub-estuaries of Mobile Bay (Alabama, USA), differing with respect to past and present anthropogenic impact. Analyses indicate that the Fish River is the most contaminated among the sub-estuaries investigated; levels of As found in Fish River sediments fall within a range that could potentially cause adverse effects in biota. Sediment As concentrations were only moderately correlated with those in V. neotropicalis; no correlation was found between sediment and plant Hg levels. However, several parameters could have masked such potential relationships (e.g., differences in sediment characteristics and "biological dilution" phenomena). Results presented herein highlight the numerous parameters that can influence metal/metalloids accumulation in aquatic plants as well as species-specific responses to trace element contamination. Finally, this study underscores the need for further investigation into contaminant bioaccumulation in ecologically and economically important coastal environments.
砷（As）和汞（Hg）是毒性最大的金属/类金属之一。本研究的总体目标是调查这些痕量元素在热带南美苦草（Vallisneria neotropicalis）中的生物累积情况，该物种是水生环境中的关键营养物种。为此，在阿拉巴马州莫比尔湾（美国）的亚河口处，对不同过去和现在人为影响的沉积物和天然热带南美苦草种群中 As 和 Hg 浓度进行了测定。分析表明，在调查的亚河口处，鱼河污染最严重；在鱼河沉积物中发现的 As 水平处于可能对生物产生不利影响的范围内。沉积物中 As 的浓度与热带南美苦草中的 As 浓度只有中度相关；未发现沉积物与植物 Hg 水平之间存在相关性。然而，有几个参数可能掩盖了这种潜在的关系（例如，沉积物特征和“生物稀释”现象的差异）。本文的结果强调了影响水生植物中金属/类金属累积的众多参数以及物种对痕量元素污染的特定反应。最后，本研究强调需要进一步研究生态和经济上重要的沿海环境中的污染物生物累积。
