电子垃圾拆解区农田土壤和地表水重金属污染特征和潜在风险评价  

Characteristics and risk assessment of heavy metal in farmland soils and surface water in e-waste dismantling area

作　　者：郑永立 朱明 郑彤 姚倩 李红艳 李慧 于云江 ZHENG Yongli;ZHU Ming;ZHENG Tong;YAO Qian;LI Hongyan;LI Hui;YU Yunjiang(College of Resources and Environment,Yangtze University,Hubei Key Laboratory of Petroleum Geochemistry and Environment,Wuhan,430100,China;State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment,South China Institute of Environmental Sciences,Ministry of Ecology and Environment,Guangzhou,510655,China)

机构地区：[1]长江大学资源与环境学院,油气地球化学与环境湖北省重点实验室,武汉430100 [2]生态环境部华南环境科学研究所,国家环境保护环境污染健康风险评价重点实验室,广州510655

出　　处：《环境化学》2023年第9期2946-2960,共15页Environmental Chemistry

基　　金：中央级公益性科研院所基本科研业务专项(PM-zx703-202204-119);国家重点研发计划项目(2021YFC1808904)资助.

摘　　要：电子垃圾的不当拆解导致大量污染物释放到环境中严重影响到生态环境和人类健康,本研究选取典型电子垃圾拆解区广东省汕头市贵屿镇周边区域农田土壤和地表水为研究对象,分别运用单因子指数法、内梅罗指数法、潜在生态风险评价模型和USEPA的健康风险评价模型分析Pb、Zn、Cu、Cr、Ni、As和Cd的浓度水平、污染特征并进行风险评价.结果表明:①农田土壤中所有元素均超过广东省背景值,其中Cu、Cd、Zn和Pb大于农用地筛选值,变异系数超过95%;②农田土壤重金属总体上属于较强生态风险(RI),其中Cd具有极强的生态风险,贡献率高达78.50%,Pb和Cu具有中等生态风险,Zn、Cr、As和Ni具有轻微生态风险;③贵屿儿童总致癌风险TCR为1.92×10^(−4),风险显著,成人总致癌风险TCR为6.31×10^(−5),存在一定程度的致癌风险;Cd和As是致癌风险的主要贡献元素,成人和儿童非致癌风险可接受;④地表水重金属含量符合一类水标准和饮用水标准;RI均值为801.01,处于强烈生态风险,Cd的贡献率高达99.05%;⑤不同人群不同暴露途径非致癌风险均小于1,处于可接受范围,致癌风险按降序排列:儿童饮水(6.87×10^(−3))>成人饮水(5.17×10^(−3))>成人接触(3.61×10^(−5))>儿童接触(1.50×10^(−5)),饮水途径是致癌风险的主要暴露途径,As元素是致癌风险的主要贡献因子.The improper disassembly of electronic waste leads to the release of a large number of pollutants into the environment,which seriously affects the ecological environment and human health.In this study,the concentrations and characteristics of Pb,Zn,Cu,Cr,Ni,As and Cd in the soil and surface water collected around the e-waste dismantling area in Guiyu Town,Shantou City,Guangdong Province were analyzed.The single-factor index,the Nemero index,the potential ecological risk evaluation model and the USEPA health risk evaluation model were respectively used to evaluate the environmental risk.The results indicated that all element contents were higher than the soil background values in Guangdong Province,and the mean contents of Cu,Cd,Pb and Zn were higher than the screening value of agricultural land.Especially,the coefficient of variation of Cu,Cd,Pb and Zn all exceeded 95%.Furthermore,the heavy metals in the soil can cause heavy ecological risk overall,among which Cd can cause extremely strong ecological risk with a contribution of 78.50%,Pb and Cu can cause moderate ecological risk,and Zn,Cr,As and Ni can cause slight ecological risk.In addition,the total carcinogenic risk(TCR)for children and adults in Guiyu was 1.92×10^(−4)(high risk)and 6.31×10^(−5)(certain risk),respectively.Cd and As were the major source of carcinogenic risk,and the non-carcinogenic risk of metals for children and adults were generally acceptable.Besides,the concentrations of heavy metals in surface water were under the standard of Class I water and drinking water.The mean value of the ecological risk index was 801.01,which indicated a strong ecological risk,with the dominant contribution of Cd(99.05%).Finally,the non-carcinogenic risk from different exposure routes were acceptable(less than 1).The carcinogenic risk varied as followed:drinking water exposure for children(6.87×10^(−3))>drinking water exposure for adult(5.17×10^(−3))>dermal contact exposure for adult(3.61×10^(−5))>dermal contact exposure for children(1.50×10^(−

关 键 词：电子垃圾 土壤 地表水 重金属 风险评价 

分 类 号：X53[环境科学与工程—环境工程] X52X820.4