农耕区大气干湿沉降通量特征监测及人体健康风险评价

Monitoring of Atmospheric Dry and Wet Deposition Flux Characteristics and Human Health Risk in Agricultural Areas

为了研究农耕区大气干湿沉降元素通量特征及人体健康风险,2020年4月—2021年4月在汨罗市布设13个大气干湿沉降采样点位,系统收集了大气干湿沉降样品52件,并结合大气点位周边的表层土壤数据,对研究区大气干湿沉降特征、大气干沉降与对应土壤中重金属元素的相关性及人体健康风险评价等进行研究。结果表明:汨罗市大气干湿沉降年通量从小到大依次为Hg<Cd<As<Cr<Pb,各个元素含量间存在明显差异,Cr、Pb为汨罗市大气干湿沉降中主要的重金属元素。大气干沉降与相对应的土壤之间的相关性较低,大气干沉降不是汨罗市表层土壤中重金属元素的主要来源。As和Pb是主要潜在的非致癌风险因子,其非致癌风险商(HQ)对非致癌风险指数(HI)的贡献率占比均超过35%,但是5种重金属中的HI值<1,说明非致癌健康风险影响较小;As、Cd、Cr的重金属致癌性风险指数(CR)均小于10^(-6),所以不存在致癌性风险。儿童的As、Pb的HI分别为0.83和0.73,小于1.00,非致癌风险可能性较低。

In order to study the flux characteristics of atmospheric dry and wet deposition elements and human health risks in agricultural areas,13 atmospheric dry and wet deposition sampling points were established in Miluo City from April 2020 to April 2021.A total of 52 atmospheric dry and wet deposition samples were systematically collected,and combined with the surface soil data around the atmospheric sampling points,the characteristics of atmospheric dry and wet deposition,the correlation between atmospheric dry deposition and heavy metal elements in corresponding soil,and the human health risk assessment in the study area were investigated.The results showed that the annual flux of atmospheric dry and wet deposition in Miluo City from smallest to largest were Hg<Cd<As<Cr<Pb,and there were significant differences in the content of each element.Cr and Pb were the main heavy metal elements in atmospheric dry and wet deposition in Miluo City.The correlation between atmospheric dry deposition and corresponding soil was low,and atmospheric dry deposition was not the main source of heavy metal elements in surface soil in Miluo City.As and Pb were the main potential non-carcinogenic risk factors,and their non-carcinogenic risk quotient(HQ)contributed more than 35%to the non-carcinogenic risk index(HI).However,the HI values of the five heavy metals are less than 1,indicating that the impact of non-carcinogenic health risks was relatively small;The risk index of heavy metal carcinogenicity(CR)of As,Cd and Cr were all less than 10^(-6),indicating that there was no carcinogenic risk.The HI values for As and Pb in children were 0.83 and 0.73,respectively,which were less than 1.00,indicating a lower possibility of non-carcinogenic risks.