基于田块尺度的农田土壤和小麦籽粒镉砷铅污染特征及健康风险评价  

Characteristics of Cd,As,and Pb in Soil and Wheat Grains and Health Risk Assessment of Grain-Cd/As/Pb on the Field Scale

作　　者：肖冰 薛培英[1] 韦亮 刘成程[2] 高培培 樊利敏 杜佳燕 刘文菊[1] XIAO Bing;XUE Pei-ying;WEI Liang;LIU Cheng-cheng;GAO Pei-pei;FAN Li-min;DU Jia-yan;LIU Wen-ju(State Key Laboratory of North China Crop Improvement and Regulation,Key Laboratory of Ecological Environment of Farmland in Hebei,College of Resources and Environmental Sciences,Hebei Agricultural University,Baoding 071000,China;Chinese Research Academy of Environmental Sciences,Beijing 100012,China)

机构地区：[1]河北农业大学资源与环境科学学院,省部共建华北作物改良与调控国家重点实验室,河北省农田生态环境重点实验室,保定071000 [2]中国环境科学研究院,北京100012

出　　处：《环境科学》2020年第6期2869-2877,共9页Environmental Science

基　　金：国家自然科学基金项目(31870490);国家重点研发计划项目(2018YFC1800806);河北省高等学校创新团队领军人才培育计划项目(LJRC016)。

摘　　要：以典型镉(Cd)、砷(As)和铅(Pb)复合污染农田为主要研究对象,在田块尺度上(纵向上受周边冶炼厂和污灌河流影响,横向上受道路交通影响)重点调查分析了农田土壤和小麦籽粒中Cd、As和Pb污染特征,并采用化学致癌物和化学非致癌物模型对小麦籽粒Cd、As和Pb含量进行了人体健康风险评价.结果表明,该农田土壤为中度污染水平,土壤Cd、As和Pb含量均有不同程度超标(GB 15618-2018),点位超标率分别为100%、100%和36.7%;小麦籽粒中Cd和Pb含量超标率分别为76.7%和13.3%,As含量未超过食品安全国家标准(GB 2762-2017).在纵向上距冶炼厂和污灌河流不同距离土壤Cd、As和Pb含量无显著差异,但小麦籽粒中Cd和As含量差异显著,近组Cd和As含量比远组分别高14.9%和41.8%(P<0.05).在横向上土壤和小麦籽粒Pb含量主要受道路交通影响,最近组土壤和籽粒Pb含量分别比最远组高78.9%和471%(P<0.05).该典型污染农田中小麦籽粒Cd和As对成人和儿童均存在致癌风险(致癌风险值Ri>1×10^-4),风险值Cd>As,儿童>成人,小麦籽粒Pb尚未产生健康风险.In recent years,heavy metal pollution in farmlands has become increasingly serious because of human activities such as metal smelting,sewage irrigation,and road traffic in China.A field survey was conducted to investigate characteristics of Cd,As,and Pb in soil and wheat grains and assess the health risk of grain-Cd/As/Pb to humans on the fields scale.The farmland was influenced by smelter and sewage irrigation in the attitude and by road traffic in the horizon.The results showed that in farmland soil with moderate pollution levels,Cd,As,and Pb concentrations in soil samples all exceeded the risk screening values of farmland soil(GB 15618-2018),and the exceeding rates were 100%,100%,and 36.7%respectively;the exceeding rates of Cd and Pb concentrations in wheat grains were 76.7%and 13.3%,respectively(GB 2762-2017).Distance from smelter,river of sewage irrigation,and road had no significant effect on Cd,As,and Pb concentrations in soil but had a significant effect on Cd and As concentrations in wheat grains,with the median Cd and As concentrations of the closest group being 14.9%and 41.8%,respectively,higher than the highest group(P<0.05).The Pb concentrations in soil and wheat grains were influenced by road traffic;the median Pb concentrations of the closest group were 78.9%and 471%,respectively,higher than the highest group(P<0.05).Cd and As in wheat grains have carcinogenic risks(Ri>1×10^-4),RCd>RAs,Rchildren>Radult,while Pb poses no health risks in this farmland.

关 键 词：田块尺度 复合污染农田 小麦 重金属 污染特征 健康风险 

分 类 号：X53[环境科学与工程—环境工程]