Collaborative Innovation Center of Sustainable Forestry, Nanjing Forestry University, Nanjing, Jiangsu, China.
Key Laboratory of Watershed Geographic Sciences, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, Jiangsu, China.
Sci Rep. 2022 Mar 9;12(1):3855. doi: 10.1038/s41598-022-07864-3.
Enrichment of heavy metals in urban soils has become a major regional environmental risk. At present, research on the soil heavy metals in cities lacks risk spatial correlation analyses between different heavy metals, and there is a relative lack of assessments of the ecological and health risks. We selected Wuxi, a typical developed city of eastern China, collected and tested the contents of heavy metals in the urban soils of Wuxi in May 2020. Combined with Pb isotope analysis, ecological and health risk assessment, we found that the high heavy metal concentrations in Wuxi are mainly located in the central and western regions, and that the changes in spatial fluctuation are relatively small. The Pb isotopes in the urban soils of Wuxi are distributed in areas, such as those are related to coal combustion, automobile exhaust and urban garbage, indicating that the heavy metals in the urban soils of Wuxi are affected by human activities such as coal combustion and automobile exhaust. The average value of the potential ecological risk index of soil heavy metal Cd is 80.3 (the threshold: 40), which represents a high-risk state. Whether adults or children, the risk of soil heavy metals via ingestion is much higher than that through skin exposure. High health risk values are present in the central area of Wuxi and decrease in a ring-shaped pattern, which is similar to the population distribution of Wuxi and greatly increases the potential risk from soil heavy metals, which should be given close attention. We should develop and use clean energy to replace petroleum fossil fuels, especially in densely populated areas. This study provides technical support for the prevention and control of urban heavy metal pollution.
城市土壤重金属富集已成为重大区域性环境风险。目前，城市土壤重金属研究缺乏不同重金属间风险的空间关联分析，对生态和健康风险的评估也相对缺乏。本研究选取中国东部典型发达城市无锡，于 2020 年 5 月采集并测试了无锡市城区土壤重金属含量。结合 Pb 同位素分析、生态和健康风险评估，发现无锡市城区重金属高含量主要集中在中部和西部地区，空间波动变化相对较小。无锡市城区土壤 Pb 同位素分布区域与煤燃烧、汽车尾气和城市垃圾等人类活动有关，表明无锡市城区土壤重金属受到煤燃烧和汽车尾气等人类活动的影响。土壤重金属 Cd 的潜在生态风险指数平均值为 80.3（阈值：40），代表高风险状态。无论是成人还是儿童，通过摄食摄入土壤重金属的风险都远高于皮肤接触。无锡市中心区域存在高健康风险值，呈环形递减，与无锡市人口分布相似，大大增加了土壤重金属的潜在风险，应予以密切关注。我们应开发和利用清洁能源来替代石油化石燃料，特别是在人口密集地区。本研究为城市重金属污染的防控提供了技术支持。
