陕西省养殖水产品重金属含量状况调查及评价

2014年至2015年,在陕西省的西安市、渭南市、宝鸡市、汉中市、安康市、榆林市和铜川市采集草鱼、鲤、鲫、鲢、鳙、罗非鱼、乌鳢、俄罗斯鲟、鲶、虹鳟和大鲵等11个水产品品种共计274份样品,分别检测Zn、Cu、Hg、As、Cd和Pb 6种重金属(含类金属As)含量。这6种重金属元素在不同水产品肌肉中残留量分别为2.49~25.15、0.1L~2.15、0.000 15L~0.364 3、0.01L~0.161 9、0.000 1L~0.031 5和0.002 5~0.4 mg/kg(鲜重)。6种重金属在11种水产品中的平均含量均低于我国限量标准,综合污染指数等级为Ⅳ级,污染程度属无污染,重金属含量总体状况良好。不同养殖品种间重金属的含量水平有一定差异,大鲵体内Zn的含量水平最高,其次为鲤、鲫、鲶及罗非鱼;鲫体内Cu的含量水平显著高于其它鱼类,其次为鲤;Hg在乌鳢体内含量水平明显较高,其次为大鲵、鲢、鳙和俄罗斯鲟;As在虹鳟体内含量水平最高,其次为俄罗斯鲟和鲢。Cd和Pb的含量在11种水产品间无明显差异。分析结果表明陕西省养殖水产品重金属含量目前虹鳟、俄罗斯鲟、鲢和鳙重金属综合污染指数相对较高,潜在污染风险相对较大,重金属指标中As和Hg的潜在污染风险相对较高。

Investigation and Evaluation of heavy metal content of aquaculture products in Shaanxi

The concentrations of Zn, Cu, Hg, As, Cd and Pb were determined in 274 samples of 11 types of aquaculture products. Grass carp, Carp, Crucian carp, Silver carp, Bighead, Tilapia, Snakehead, Russian Sturgeon, Catfish, Rain-bow trout and Giant salamander were collected from Xian, Weinan, Baoji, Hanzhong, Ankang, Yulin and Tongchuan cities in Shaanxi province from 2014 to 2015. The average concentrations of these heavy metals in the muscles of the fishes were 2. 49 ~ 25. 15, < 0. 1 ~ 2. 15, < 0. 00015 ~ 0. 3643, < 0. 01-0. 1619, < 0. 0001 ~ 0. 0315 and 0. 0025 ~ 0. 4 mg/kg for Zn, Cu, Hg, As, Cd and Pb, respectively. The average contents of these six heavy metals in the 11 types of fi-shes were individually lower than the national standards of fish food safety, China. The comprehensive pollution index level was Ⅳ, belonging to pollution-free. This implies that the contents of heavy metals in fishes in these areas were safe. There were obvious differences in the contents of different heavy metals in different species of fishes. Zn concentration in Giant Salamander muscle was of the highest levels, followed in Carp, Crucian carp, Catfish, and Tilapia muscles. The Cu levels in Crucian muscle were significantly higher than that in other fishes, followed by Carp ( p<0. 05 ) . Hg level in Snakehead muscle was the highest among fishes, followed by Giant Salamander, Silver carp, Bighead and Russian Stur-geon. As level in rainbow trout was the highest, followed by Russian Sturgeon and Silver carp. There was not obvious difference in the contents of Cd ( or Pb) among these 11 species of fish. Results show that the high comprehensive pollution index of heavy metals occurred in Rainbow trout, Russian Sturgeon, Silver carp and Bighead in Shaanxi province, implying large potential pollution risk. As for the types of heavy metals, the comprehensive pollution indices of As and Hg were rela-tively high.