贵州省威宁草海主要野生鱼类重金属含量及健康风险评价

Heavy metal contents and health risk assessment of wild fish species in Caohai Lake in Weining County,Guizhou Province

【目的】了解贵州省威宁草海鱼类重金属含量水平,并进行鱼类食用安全性评价,为威宁草海的鱼类水生生态环境保护和食用安全性提供参考依据。【方法】选择黄颡鱼、鲫鱼、鲤鱼和花鳅为研究对象,测定分析其肌肉和内脏中的8种重金属含量,运用Pearson分析鱼体中重金属含量与生长参数和水体理化因子的相关性,并运用单因子污染指数法、综合污染指数法和目标危险系数法进行污染评价。【结果】4种鱼体中的重金属含量排序为Zn>Cu>Cr>Pb>As>Ni>Cd>Hg,对重金属的累积整体上表现为鲫鱼>鲤鱼>花鳅>黄颡鱼,与国家标准GB 2762—2017《食品安全国家标准食品中污染物限量》比较,除Cu、Hg、Zn、Ni和As外,其余重金属均超标。鱼体各组织的重金属含量总体表现为内脏>肌肉。鲫鱼和鲤鱼的重金属含量随年龄的增加而上升,花鳅的重金属含量则随年龄的增加而降低。Pearson相关分析结果表明,Zn和Cd与体重、Cu与体长呈显著正相关(P<0.05,下同);Hg与硝酸盐氮(NO3-N)呈极显著正相关(P<0.01);Cr与总磷(TP)和NO3-N呈显著负相关;Cu与TP呈显著正相关。单因子污染指数表明,除Hg外,其余重金属在鱼体中有污染状况;综合污染指数表明,花鳅的肌肉处于轻度污染水平,鲫鱼和鲤鱼的内脏分别处于重度和中度污染水平。健康风险评价显示4种鱼的单一重金属危害系数(THQ)和复合重金属危害系数(TTHQ)在成人和儿童中均小于1,儿童的THQ和TTHQ均大于成人。【结论】威宁草海鱼体内存在重金属含量超标现象,重金属污染主要元素是As,食用黄颡鱼、鲤鱼、鲫鱼和花鳅虽然不会造成潜在健康风险,但相关部门对鱼类重金属的污染应给予管控。

【Objective】To study the level of heavy metal contents and health risk assessment of wild fishes in Caohai Lake,Weining,Guizhou,and provide reference for the protection of aquatic ecological environment and food safety of fish in Caohai Lake.【Method】The contents of heavy metals in muscle and tissues of Pelteobagrus fulvidraco,Carassius auratus,Cyprinus carpio and Cobitis sinensis were measured and analyzed.Pearson correlation was used to analyze the correlation between heavy metal contents and growth parameters,and water physical and chemical factors.The single factor pollution index method,integrated pollution index method and target hazard quotient method were used to estimate pollution levels.【Result】The results showed that the average levels of these heavy metals decreased in the order of Zn>Cu>Cr>Pb>As>Ni>Cd>Hg in the four fish species.The accumulation of heavy metals decreased in the order of C.auratus>C.carpio>C.sinensis>P.fulvidraco.The contents of all heavy metals except Cu,Hg,Zn,Ni and As were higher than the national standards GB 2762—2017 Food Safety National Standard Limit of Contaminants in Food.In general,the contents of heavy metals in viscera was higher than muscle.The heavy metal contents in C.auratus and C.carpio increased with age.The heavy metal contents of C.sinensis decreased with the increase of age.Pearson correlation showed that Zn and Cd were significantly positively correlated with body weight(P<0.05,the same below),Cu was significantly positively correlated with body length,Hg was extremely positively correlated with nitrate nitrogen(NO3-N)(P<0.01),Cr was significantly negatively correlated with total phosphorus(TP)and NO3-N,and Cu was significantly positively correlated with TP.The single factor pollution index showed that the contents of all heavy metals except Hg were contaminatedin fishes.The integrated pollution index showed thatthe muscle of C.sinensis was in the mild level of heavy pollution,and the internal organs of C.auratusand C.carpio were in the heavy and medium level of heavy pollution respectively.Health risk assessment showed that the single target hazard quotients and total target hazard quotients of P.fulvidraco,C.auratus,C.carpio and C.sinensis for children and adults were less than 1.The single target hazard quotients and total target hazard quotients of four species of fish for children were higher than adults.【Conclusion】The contents of some heavy metals of fish are higher than the national standards in Caohai Lake.The main elements of heavy metals pollutionare As.P.fulvidraco,C.auratus,C.carpio and C.sinensis will not cause health risks of heavy metals.Related departments should pay great attention to heavy metals pollution of fish.