湘江综合枢纽工程蓄水后湘江长沙段鱼类重金属残留分析与评价

Analysis and Evaluation of Heavy Metal Residues in Fishes in the Changsha Section of Xiangjiang River After Impoundment of Xiangjiang Comprehensive Hub Project

以湘江综合枢纽工程蓄水前后的湘江长沙段鱼类为研究对象,采集47条鲤鱼、32条鲫鱼的肌肉组织样品,进行重金属的污染评价和健康风险评价。结果表明,2013~2017年,样品中的5种重金属元素检出率为100%,其中Cd,Pb,Cr,Hg和As含量分别在0.097~0.210,0.102~0.211,0.252~0.698,0.039~0.094和0.060~0.100 mg/kg;在工程蓄水后,样品中5种重金属残留量呈下降趋势;不同鱼类对Cd富集能力不同,1 kg以上鲤鱼对Cd富集能力较强。综合污染指数表明,湘江长沙段已从2013年的污染水平降到了2017年的轻污染水平。健康风险评估表明,目前湘江长沙段鱼类肌肉组织中5种重金属危害系数均小于1,不存在单一重金属食用风险。

Fishes in the Changsha section of the Xiangjiang River before and after the impoundment of the Xiangjiang comprehensive hub project,including 47 carps and 32 crucians,were taken as the samples to collect their muscle tissue for study.Then,the heavy metal pollution assessment and health risk assessment were made.The results showed that from 2013 to 2017,5 heavy metal elements were 100%detected in the samples,with the contents of Cd,Pb,Cr,Hg and As at 0.097~0.210,0.102~0.211,0.252~0.698,0.039~0.094 and 0.060~0.100 mg/kg respectively.After the impoundment of Xiangjiang comprehensive hub project,it is shown that the contents of 5 kinds of heavy metal residues in the samples were in decrease.Different fish had a different Cd enrichment,and the carp weighing above 1 kg showed a stronger Cd enrichment.The comprehensive pollution index indicated that the pollution level of the Changsha section of Xiangjiang River had dropped to a light pollution level from 2013 to 2017.The health risk assessment shows that the hazard factors of five heavy metals in fish muscle tissues in the Changsha section of Xiangjiang River are all less than 1,indicating there is no risk of any single heavy metal for eating those fish.