Shenzhen Key Laboratory of Edible and Medicinal Bioresources, Shenzhen Research Institute, Hong Kong University of Science and Technology (HKUST), Shenzhen 518000, Department of Ocean Science, HKUST, Clearwater Bay, Kowloon, Hong Kong, China.
South China Sea Environmental Monitoring Center, State Oceanic Administration, Guangzhou 510300, China.
Sci Total Environ. 2019 Jun 15;669:746-753. doi: 10.1016/j.scitotenv.2019.03.164. Epub 2019 Mar 12.
Bivalves are extensively employed as biomonitors of coastal pollution, but the comparability among different species and geographic environments needs to be further scrutinized. The present study conducted a meta-analysis of trace metals (Ag, Cd, Cr, Cu, Ni, Pb, Ti, and Zn) in the soft tissues of three groups of marine bivalves (oysters, mussels, and clams) collected from China and worldwide. By conducting cumulative frequency distribution analysis of metal distribution, we modeled the 5% cumulative values as the bio-baseline metal concentrations in these bivalves. We further modeled their potential baseline concentrations using a well-developed biokinetic model. The baseline concentrations of Cd, Cu, and Zn in the tissue-specific Environmental Quality Standards (EQSs) for China were 0.99, 34.5, and 340 μg/g dw in oysters, 0.38, 4.32, and 49.6 μg/g dw in mussels, and 0.35, 3.02, 51.4 μg/g dw in clams, respectively. Of the 8 metals examined in this study, the calculated baseline concentrations of Ag, Cr, Cd, Cu and Zn in the oysters were 3.7-48, 2.7-3.6, 2.6-2.8, 8.0-11.4, 6.6-6.8 times higher than those in the mussels and clams, and only Ti showed comparable baseline concentrations among the three bivalves (8.43-9.67 μg/g dw). These data strongly suggested the inter-group as well as inter-metal difference in the baseline metal concentrations in marine bivalves. Further, the potential baseline concentrations of Cd and Cu predicted by the biokinetic model were comparable to those modeled by the probability frequency distribution. Combined statistical frequency analysis and biokinetic modeling therefore provided an innovative method to establish the baseline metal concentrations in bivalves and the tissue-specific EQSs, which are now urgently needed for coastal management, biomonitoring, and geochemical records in the world.
双壳类动物被广泛用作沿海污染的生物监测物，但不同物种和地理环境之间的可比性仍需进一步研究。本研究对来自中国和世界各地的三组海洋双壳类动物（牡蛎、贻贝和蛤）的软组织中的痕量金属（Ag、Cd、Cr、Cu、Ni、Pb、Ti 和 Zn）进行了荟萃分析。通过对金属分布的累积频率分布分析，我们将 5%累积值模拟为这些双壳类动物的生物基线金属浓度。我们进一步使用成熟的生物动力学模型模拟了它们的潜在基线浓度。中国组织特异性环境质量标准（EQSs）中 Cd、Cu 和 Zn 的基线浓度分别为牡蛎中 0.99、34.5 和 340μg/g dw，贻贝中 0.38、4.32 和 49.6μg/g dw，蛤中 0.35、3.02 和 51.4μg/g dw。在本研究中检查的 8 种金属中，计算出的牡蛎中 Ag、Cr、Cd、Cu 和 Zn 的基线浓度分别是贻贝和蛤的 3.7-48、2.7-3.6、2.6-2.8、8.0-11.4 和 6.6-6.8 倍，只有 Ti 在这三种双壳类动物中的基线浓度相当（8.43-9.67μg/g dw）。这些数据强烈表明海洋双壳类动物的基线金属浓度存在组间和金属间差异。此外，生物动力学模型预测的 Cd 和 Cu 的潜在基线浓度与概率频率分布模型的预测值相当。因此，结合统计频率分析和生物动力学建模，为建立双壳类动物和组织特异性 EQSs 的基线金属浓度提供了一种创新方法，这对于沿海管理、生物监测和全球地球化学记录来说是迫切需要的。
