摘要：
采用电感耦合等离子体质谱和原子荧光形态检测法分析宁海、象山、舟山3个养殖区内常见3种海产贝类（牡蛎、缢蛏、血蚶）中Cd、Cu、Cr、Pb、As、Hg等重金属的总含量，并采用化学逐级提取法系统研究水煮加工前后贝类中Cd、Cu、Cr、Pb重金属的形态分布和As、Hg中有机和无机的形态分布。结果表明，3个养殖区牡蛎、缢蛏、血蚶中Cd、Cr、Cu、Pb、As均有不同程度的超标，且Cu和Cd、Cr和Pb之间存在显著相关性，As的超标检出率达77.78%，Hg的残留量均低于限量标准；此外金属形态分析研究结果表明，水煮加工方式对Cd、Cu、Cr、Pb中酸可提取态、氧化结合态、有机结合态和残余态的含量影响较大，而对As和Hg的有机态和无机态影响较小。海洋贝类中重金属元素的含量和水煮加工前后该元素形态的变化量可作为评价海洋贝类中重金属生物有效性的指标。%Heavy metals including Cd, Cu, Cr, Pb, As and Hg in oysters, razor clams and blood clams collected from three breeding areas located, respectively, in Ninghai, Xiangshan and Zhoushan of Zhejiang province were investigated by inductively coupled plasma mass spectrometry (ICP-MS) and atomic fluorescence spectrometry. Sequential extraction procedure was introduced to determine metal speciation of Cd, Cu, Cr, Pb and organic and inorganic forms of arsenic and mercury before and after boiling. The results showed that the contents of Cd, Cr, Cu, and Pb varied among three marine shellfish, and significant correlations existed between Cu and Cd, and between Cr and Pb. Meanwhile, the percentage of samples exceeding the standard limit of arsenic was 77.78% while Hg residues were lower than the standard limit. As indicated by comparison of the contents of acid extractable, reducible, oxidizable and residual fractions of Cd, Cu, Cr, and Pb before and after boiling, boiling had significant effect on speciations of Cd, Cu, Cr, and Pb, but had little effect on organic and inorganic forms of arsenic and mercury. In conclusion, the content of heavy metal elements and the variation of metal speciation before and after boiling can be used as indexes to evaluate the bioavailability of heavy metals in marine shel fish.
