南方某铅锌锰冶炼区周边大气降尘重金属污染水平及风险评价

Pollution level and risk assessment of heavy metals in the atmospheric dustfall around a lead-zinc-manganese smelting area in south China

于2016年8月至2017年1月分别对南方某铅锌锰冶炼区周边(污染区)及大新村(对照区)进行大气降尘干法采集,测定了大气降尘中Cd、Zn、Pb、Mn、Cu、As、Ni、Cr含量,采用富集因子法、潜在生态风险指数法和健康风险评价对大气降尘重金属污染进行源解析与风险评价。结果表明,污染区大气降尘中Cd、Cr、Mn、Ni、Pb、As、Zn、Cu均值分别为166.6、104.5、6 109.0、80.9、635.9、53.6、8 838.5、180.3mg/kg,分别为背景值的691.3、2.1、11.6、2.4、24.5、2.9、106.6、6.9倍。富集因子法分析得出,污染区大气降尘中Cd、Zn和Pb主要来源于铅锌冶炼以及电解锰企业;Mn、Cu、As和Ni在大气降尘中富集程度次之,既受自然源,也受人为源影响。生态风险评价表明,污染区大气降尘中Cd为极强生态危害,Pb、Zn属于强生态危害,Cu、As、Ni、Cr均为轻微生态危害,综合潜在生态风险达到很强生态危害等级。健康风险评价表明,污染区大气降尘中重金属主要健康风险来源于非致癌风险,致癌风险可忽略。大气降尘中Pb、As、Cd经手-口摄入途径对儿童存在非致癌风险,应采取措施降低污染区大气降尘中Pb、As、Cd含量,控制手-口摄入途径对儿童的非致癌风险。

Atmospheric dustfall was collected around a lead-zinc-manganese smelting area in south China(pollution area)and Daxin Village(control area)from August 2016 to January 2017.Concentrations of Cd,Zn,Pb,Mn,Cu,As,Ni,Cr in the atmospheric dustfall were measured.Enrichment factor method,potential ecological risk index and health risk assessment for the source of heavy metal pollution in atmospheric dustfall and risk assessment were also carried out.Results showed that the average values of Cd,Cr,Mn,Ni,Pb,As,Zn and Cu in the dustfall around the pollution area were 166.6,104.5,6 109.0,80.9,635.9,53.6,8 838.5 and 180.3 mg/kg,which were 691.3,2.1,11.6,2.4,24.5,2.9,106.6 and 6.9 times of background values,respectively.The enrichment factor analysis showed that the enrichment degree of Cd,Zn and Pb in atmospheric dustfall was the most intense,mainly from lead-zinc smelting enterprises and electrolytic manganese enterprises.The enrichment degree of Mn,Cu,As and Ni in atmospheric dustfall was the second,which was affected by both natural and man-made sources.The ecological risk assessment showed that Cd in the dustfall around the pollution area had an extremely strong ecological hazard,while Pb and Zn had strong ecological hazard,and Cu,As,Ni and Cr had minor ecological hazard.The comprehensive potential ecological risk reached a very strong ecological hazardous level.The health risk assessment indicated that the main health risk of heavy metals in the atmospheric dustfall around the pollution area were derived from noncarcinogenic risk,and the cancer risk was negligible.Pb,As and Cd in the pollution area had non-carcinogenic risk to children through hand-mouth intake.Measures should be taken to reduce the content of Pb,As,Cd in the atmospheric dustfall in the pollution area to control the non-carcinogenic risk to children through the hand-mouth intake.