Samples of constructive dust were collected from 9 areas in 4 construction areas in Guiyang .The con-tent of Cu, Pb, Zn in samples of different particle sizes and multi-particle size were analyzed .Research into the ex-posure and health risk assessment of Cu , Pb, Zn on the medium and fine size dust was carried out by using USEPA health risk assessment model .Results showed that:the range of the change for the three heavy metals in construc-tion dust in Guiyang was quite large and there existed different degrees of pollution , in which Zn was the main pol-lutant.In terms of enrichment of Cu, Pb, Zn, there was a greatly different in 9 areas, and the higher of Cu content was in the outside road, gate, metal area; Pb was in gate, outside and inside road; Zn was in building, stairs, gate, inside road , metal area .Particle size distribution had a significant influence on contents .Fine size was at the main pollution level .The contents of the three heavy metals in medium and fine size existed greatly different in 9 areas and their distribution was similar with their total contents .In 9 areas, three heavy metals were mainly en-riched in fine particle sizes and the enrichment ratio was above 40%, and the lowest enrichment ratio appeared in coarse particle size .Human exposure risk assessment showed that hand-mouth intake was the main way for Cu , Pb, Zn exposure to medium and fine particle size of constructive dust , and the children 's risk was higher than the adults', but the non-cancer hazard indexes of the three heavy metals was lower than its threshold values , suggesting that it would not harm the health .Additionally , the non-cancerous risk for children and adults was different in 9 ar-eas.For children, the indexes were nearly 1 in the outside and inside road , gate, showing a potential non-cancer-ous risk to the health of the children .However, for adults, the indexes in 9 areas were all below 0.1, indicating no non-cancerous risk to the health of the adults .%以贵阳市4个建筑工地9个区域的建筑灰尘为研究对象,分析不分粒径混合样品中Cu、Pb、Zn的总量,并对3种重金属含量的粒径分布及其中、细颗粒灰尘重金属健康风险进行评估.实验结果表明:贵阳市建筑灰尘中Cu、Pb、Zn含量的变化范围较大,存在不同程度污染,其中Zn为超过背景值倍数最高的重金属.3种重金属的富集存在空间差异,Cu的较大值出现在建筑区旁道路、建筑区门口、金属堆放区,Pb的较大值出现在建筑区门口、建筑区内道路、建筑区旁道路,Zn的较大值出现在楼内、楼梯、建筑区门口、建筑区内道路、金属堆放区.不同重金属的粒径分布差异较大,细颗粒是主要的污染粒径区间.中、细颗粒重金属含量存在显著空间差异,与重金属全量空间分布基本一致.3种重金属在各区域都表现出细颗粒富集最大,均超过40%,粗颗粒富集最小.手-口摄入途径是人群对中、细颗粒建筑灰尘Cu、Pb、Zn暴露的主要途径.儿童非致癌风险高于成人,但3种重金属对人群非致癌风险均小于阈值1;对人群不造成健康危害.建筑灰尘重金属非致癌风险对不同人群在空间上差异较大,建筑区内道路、建筑区旁道路、建筑区门口灰尘对儿童的叠加风险指数接近1,潜在危险不容忽视;成人在各区域的叠加风险指数均未超过0.1,未表现出突出的健康风险.
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