路旁土壤-小麦系统重金属污染及其健康风险评价

分别于距离路基0、5、10、15、25、35、50、100、200、300 m处采集土壤、麦苗和籽粒样品,在测定样品重金属Pb、Cd、Zn、Cr和Cu含量的基础上,开展路旁土壤-小麦系统重金属分布和污染状况分析,并对膳食小麦引起的健康风险进行评价。结果表明,土壤-小麦系统重金属含量随着离路基距离的增加呈先增加后减少的趋势,重金属含量表现为土壤>麦苗>小麦籽粒;膳食小麦所致的Cd个人健康风险较大,在距路基50 m范围内超过ICRP可接受标准的1.6～3.2倍;不存在非致癌重金属健康风险,致癌重金属Cd的个人健康风险占总风险的94.81%,是最主要的健康危害物质。

Heavy Metal Contamination and Health Risk Assessment in Roadside Soil-wheat System

The samples of soils,wheat seedlings and grains were collected at the distance of 0,5,10,15,25,35,50,100,200 and 300 m from the road edge.Spatial distribution,accumulation,contamination,and health risk assessment of heavy metals（Pb,Cd,Zn,Cr and Cu） were discussed.The results showed that： heavy metal concentrations in these samples increased first,and then decreased with increasing distance from the road.The order of heavy metal content is soil wheal seedling grain.The values of cadmium health risk for wheat grains in the sampling sites within 50 m from the highway were from 1.6 to 3.2 times of the acceptable value recommended by International Commission Radiological Protection（ICRP）.Chromium health risk by eating wheat grains was very critical in the studying areas.There were no health risk of copper,lead and zinc in all samples.The health risk of chemical carcinogens was about 94.81% of total health risk,and only 5.19% for chemical non-carcinogens.