三峡库区鲤鱼重金属污染状况及其健康风险评估

Health risk assessment of heavy metal contamination in carps from Three Gorges

为了评估三峡库区鲤鱼中4种重金属污染状况及其对当地居民存在的健康风险,利用微波消解-火焰原子吸收光谱方法测定鲤鱼肌肉中Pb、Cd、Cu和Cr的含量,利用目标危险系数(THQ)和最大允许日消费率(CRLim)评估食用鲤鱼所带来的健康风险。结果表明,鲤鱼中Pb、Cd、Cu和Cr平均含量分别为0.348、0.147、5.837、1.270mg/kg,均符合国际或国家卫生限量标准。与长江、南四湖、北江、沱江等水域相比,三峡库区鲤鱼中Pb的含量较低,Cd含量水平相当,Cu、Cr的含量升高;与库区蓄水前相比,重金属污染有所改善,与蓄水后同水域相比,重金属污染程度有所增加。三峡库区鲤鱼Pb、Cd、Cu和Cr的CRLim分别为0.268～0.753、0.158～0.446、0.160～0.449、0.055～0.155kg/d。三峡库区鲤鱼Pb、Cd、Cu和Cr的THQ均小于1,且重金属的总危害商数(TTHQ)也小于1。结合THQ和CRLim研究结果综合评价,三峡库区鲤鱼对沿岸居民不存在健康风险。

The purpose of this study was to assess the pollution degree of four heavy metals in carp and their health risks to local residents in the Three Gorges Reservoir area.The carp samples were digested by microwave digestion instrument and the concentrations of Pb,Cd,Cu and Cr in carp were detected by flame atomic absorption spectrometry.Target hazard quotient(THQ)and maximum allowable consumption rate(CRLim)were used to assess the health risk of eating carp.The results of research showed that the average concentration of Pb,Cd,Cu and Cr in carp was 0.348,0.147,5.837 and 1.270 mg/kg,respectively.The detected levels of the studied metals were below the legal national and inter national limited standards.Compared with Yangtze River,Nansi Lake,Beijiang River,Tuojiang River,the Pb level was lower,Cd level was quite,and Cu,Cr were higher.Compared with the reservoir area before impoundment,the pollution of heavy metals had been improved,and the pollution degree of heavy metals had increased relative to the water area after impoundment.The results showed that the maximum allowable consumption rate of carp was 0.268-0.753,0.158-0.446,0.160-0.449 and 0.055-0.155 kg/d for Pb,Cd,Cu and Cr,respectively.The THQ for Pb,Cd,Cu and Cr were less than 1,and the total target hazard quotient value(TTHQ)was also below 1.According to the comprehensive evaluation of THQ and CRLim,carp in the Three Gorges Reservoir Area had no health risk to coastal residents.