Department of Biology, San Diego State University, San Diego, CA, 92182-4614, USA; Graduate Group in Ecology, University of California Davis, Davis, CA, 95616, USA.
Instituto de Ciências do Mar, Universidade Federal do Ceará, Fortaleza, CE, 60165-081, Brazil.
Environ Pollut. 2019 May;248:684-695. doi: 10.1016/j.envpol.2019.02.070. Epub 2019 Feb 25.
Batoids (Chondrichthyes: Batoidea; e.g. stingrays, skates, and guitarfish) comprise more than 55% of elasmobranch taxa and represent ecologically important predators in benthic and pelagic habitats. Although overexploitation and habitat degradation are the two biggest threats to batoid populations, coastal and oceanic pollution is also a pervasive potential threat. In this systematic review, we compile published scientific literature on trace metals and persistent organic pollutants (POPs) contamination in elasmobranch species of the Batoidea superorder and present contamination patterns, exposure effects, and potential human exposure risks to most reported contaminants. We found batoids to accumulate a wide range of trace metals, including mercury (Hg), arsenic (As), lead (Pb), copper (Cu), cadmium (Cd) and zinc (Zn). Accumulation of POPs is reported for chlordanes, dichlorodiphenyltrichloroethane (DDT), polychlorinated biphenyl (PCB), dieldrin, Heptachlor epoxide, hexachlorobenzene and perfluoroalkyl substances (PFAS). Hg levels in muscle tissue were significantly different among oceanic basins and habitats, consistent with previous global assessments of Hg oceanic background levels. Some batoid species presented Hg levels higher than large pelagic teleost fishes and comparable to sharks. Ecological traits such as, bottom feeding, upper trophic position and elasmobranch-specific physiology and metabolism are discussed as potential factors associated with Hg uptake and accumulation in batoids. Some species exceeded USEPA's maximum contamination safety limits in edible tissues for Hg, As and ΣPCBs. For most trace metals and POPs, there is a lack of studies focusing on contamination levels in batoids. We recommend future research increasing reporting on POPs and trace metals besides Hg in batoids to further investigate the role of Elasmobranch as a bioindicator for marine pollution.
板鳃鱼类（软骨鱼纲：板鳃亚纲；例如鳐鱼、魟鱼和锯鳐）占软骨鱼类分类群的 55%以上，是底栖和海洋生境中重要的掠食性鱼类。尽管过度捕捞和栖息地退化是板鳃鱼类种群面临的两大威胁，但沿海和海洋污染也是一个普遍存在的潜在威胁。在本系统综述中，我们汇编了关于板鳃亚纲软骨鱼类种属中痕量金属和持久性有机污染物（POPs）污染的已发表科学文献，并介绍了污染模式、暴露效应以及大多数报告的污染物对人类的潜在暴露风险。我们发现，板鳃鱼类积累了广泛的痕量金属，包括汞（Hg）、砷（As）、铅（Pb）、铜（Cu）、镉（Cd）和锌（Zn）。氯丹、滴滴涕（DDT）、多氯联苯（PCB）、狄氏剂、六氯环戊二烯氧化物、六氯苯和全氟烷基物质（PFAS）等 POPs 的积累也有报道。肌肉组织中的 Hg 水平在海洋盆地和生境之间存在显著差异，与之前对全球海洋 Hg 背景水平的评估一致。一些板鳃鱼类的 Hg 水平高于大型远洋硬骨鱼类，与鲨鱼相当。底栖觅食、较高的营养级位置以及板鳃鱼类特有的生理和代谢等生态特征被认为是与板鳃鱼类中 Hg 吸收和积累相关的潜在因素。一些物种的可食用组织中 Hg、As 和ΣPCBs 的含量超过了美国环保署的最大污染安全限量。对于大多数痕量金属和 POPs，缺乏针对板鳃鱼类污染水平的研究。我们建议未来的研究增加对板鳃鱼类中除 Hg 以外的 POPs 和痕量金属的报告，以进一步研究板鳃鱼类作为海洋污染生物指示剂的作用。
