Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, 11 A Datun Road, Beijing 100101, China.
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China.
Int J Environ Res Public Health. 2020 Apr 29;17(9):3099. doi: 10.3390/ijerph17093099.
This study provides an overview of the studies of heavy metal pollution regarding As, Cd, Cr, Hg, Pb, Cu, Zn and Ni in the urban soils throughout 71 cities of China, based on data from online literature, during the period 2003-2019. The concentrations, spatial distributions, contamination degrees and health risks of heavy metals in the urban soils were evaluated. The results demonstrated that the mean values of eight heavy metals all exceeded the soil background values in China, and the kriging interpolation method showed that the hot-spot cities with heavy metal contamination in urban soils were mainly concentrated in the southwest, southcentral, southeast coast, northcentral and northwest regions of China. The geoaccumulation index () indicated that Hg and Cd were at moderate contamination levels and that the levels of the other six metals did not appear contamination. The pollution index () showed that Cd and Hg reached high contamination levels, and the other metals reached moderate contamination levels. The integrated pollution index () and potential ecological risk index () indicated that the integral urban soils in the study areas ranked high contamination levels and moderate ecological risk degree, respectively, and Cd and Hg should be labeled as priority metals for control in the urban soils around China. The human health risk assessments for the heavy metals indicated that ingestion was the dominant exposure pathway for having adverse effects on human health. The mean Hazard index () values of eight heavy metals all showed that adverse effects on human health were unlikely, and the mean carcinogenic () values of As, Cr and Ni for children and adults all suggested an acceptable carcinogenic risk to human beings. In addition, children exposed to these heavy metals faced more serious non-carcinogenic and carcinogenic health threats compared to adults. The results could provide valuable information for demanding the better control of heavy metal pollution and mitigation of the adverse effects on residents by environmental regulators in national urban regions.
本研究基于 2003-2019 年期间的在线文献数据，综述了中国 71 个城市中城市土壤中 As、Cd、Cr、Hg、Pb、Cu、Zn 和 Ni 等重金属污染的研究情况。评估了城市土壤中重金属的浓度、空间分布、污染程度和健康风险。结果表明，八种重金属的平均值均超过了中国土壤背景值，克立格插值法显示，重金属污染热点城市主要集中在中国西南、中南部、东南沿海、中北部和西北部。地积累指数（）表明 Hg 和 Cd 处于中度污染水平，其他六种金属未出现污染。污染指数（）表明 Cd 和 Hg 达到了高污染水平，其他金属达到了中度污染水平。综合污染指数（）和潜在生态风险指数（）表明，研究区整体城市土壤处于高污染水平和中度生态风险程度，Cd 和 Hg 应被标记为中国城市土壤中优先控制的重金属。重金属的人体健康风险评估表明，摄入是对人体健康产生不利影响的主要暴露途径。八种重金属的平均危害指数（）值均表明对人体健康产生不利影响的可能性较小，儿童和成人的 As、Cr 和 Ni 的平均致癌（）值均表明对人类存在可接受的致癌风险。此外，与成年人相比，接触这些重金属的儿童面临着更严重的非致癌和致癌健康威胁。研究结果可为环境监管机构在全国城市地区要求更好地控制重金属污染和减轻对居民的不利影响提供有价值的信息。
