海河干流水产品汞污染特征及摄入风险评估

Pollution Characteristics Analysis and Risk Assessment of Total Mercury and Methylmercury in Aquatic Products of the Haihe Stem River

通过现场实地采样和实验测定分析了天津市海河干流水产品中汞含量水平及食用人群的暴露风险.结果表明,海河淡水水产品中甲基汞和总汞的含量(以湿重计)分别为42.51 ng·g^(-1)和77.31 ng·g^(-1),甲基汞是水生生物中汞的最主要存在形式,且与鱼体中总汞含量水平显著相关.鱼体在不同器官中和不同养殖方式下的汞含量水平差异显著.海河淡水鱼类和底栖动物的甲基汞富集系数(BCF)分别为1.00×105m L·g^(-1)和4.23×104m L·g^(-1),与总汞相比,甲基汞具有更强的生物富集特性.海河淡水生物生物链中的甲基汞和总汞营养级放大系数分别为1.38和1.36.水产品中的甲基汞和总汞含量最大允许含量均低于我国国家标准限定值,但同时应该注意,以海河淡水野生鱼类为食的儿童,汞摄入风险相对较高,其总汞和甲基汞摄入量分别达到154.07 ng·(kg·d)^(-1)和81.11 ng·(kg·d)^(-1).

In this study,we analyzed the concentrations of total mercury（ THg） and methylmercury（ Me Hg） in the aquatic products from the Haihe Stem River,and also assessed the risk for the consumers. According to our results,the Me Hg and THg concentrations in the aquatic products were 42. 51 and 77. 31 ng·g^（-1）,respectively（ wet weight）. The majority of THg in the aquatic products existed in the form of Me Hg（ accounting for over 50%）. The mercury concentrations varied significantly among different organs in the fish.The BCFs of Me Hg for the fish and zoobenthos in the Haihe River were 1. 00 × 105 and 4. 23 × 104 m L·g^（-1）,respectively. Compared with THg,Me Hg could accumulate more easily in the aquatic products. Generally,the maximum Me Hg and THg concentrations of the aquatic products were much lower than the limit values in China. However,compared with the adults,the Me Hg exposure risk for the children was higher,and the THg and Me Hg intake could be as high as 154. 07 ng·（ kg·d）^（-1）and 81. 11 ng·（ kg·d）^（-1）,respectively.