State Key Laboratory of Biogeology and Environmental Geology, China University of Geo sciences, (Beijing), Beijing, 100083, PR China; Institute of Earth Sciences, China University of Geosciences (Beijing), Beijing, 100083, PR China; The State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China.
The State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
Environ Res. 2024 Dec 1;262(Pt 2):119955. doi: 10.1016/j.envres.2024.119955. Epub 2024 Sep 6.
Particle size effects significantly impact the concentration and toxicity of heavy metals (HMs) in dust. Nevertheless, the differences in concentrations, sources, and risks of HMs in dust with different particle sizes are unclear. Therefore, guided by the definition of atmospheric particulate matter, dust samples with particle sizes under 1000 μm (DT), 100 μm (DT), and 63 μm (DT) from Beijing kindergartens were collected. The concentrations of HMs (e.g., Cd, Pb, Zn, Ni, Cr, Ba, Cu, V, Mn, Co, and Ti) in dust samples with different particle sizes were measured. Besides, the differences in HM concentrations, contamination levels, sources, and source-oriented health risks in dust samples of different particle sizes were systematically explored. The results show that the concentrations of Mn, V, Zn, and Cd gradually increase with decreasing dust particle sizes, the concentrations of Ba and Pb show a decreasing trend, and the concentrations of Cr, Cu, Ni, and Co display an increasing and then decreasing trend. The degree of contamination of HMs in dust of different particle sizes varies, with Cd being the most dominant contaminant. Compared with DT and DT, DT is the most polluted. In addition, the sources of HMs in DT, DT, and DT become more single with decreasing particle size, which may be mainly due to the particle-size effect inducing the redistribution of HMs in different sources. Notably, the potential health risk is higher in DT than in DT and DT. The highest contribution of industrial sources to the health risk is found in DT, which is mainly caused by highly toxic chromium (Cr). This work emphasizes the importance of considering particle size in risk assessment and pollution control, which can provide a theoretical basis for precise management of HMs pollution in dust.
粒径对粉尘中重金属（HMs）的浓度和毒性有显著影响。然而，不同粒径粉尘中 HMs 的浓度、来源和风险差异尚不清楚。因此，本研究以大气颗粒物定义为指导，采集了北京市幼儿园粒径小于 1000μm（DT）、100μm（DT）和 63μm（DT）的粉尘样品。测定了粉尘样品中 HMs（如 Cd、Pb、Zn、Ni、Cr、Ba、Cu、V、Mn、Co 和 Ti）的浓度。此外，系统探讨了不同粒径粉尘样品中 HM 浓度、污染水平、来源及源导向健康风险的差异。结果表明，Mn、V、Zn 和 Cd 的浓度随粉尘粒径的减小而逐渐增加，Ba 和 Pb 的浓度呈下降趋势，Cr、Cu、Ni 和 Co 的浓度呈先增加后减小的趋势。不同粒径粉尘中 HMs 的污染程度不同，Cd 是最主要的污染物。与 DT 和 DT 相比，DT 污染最严重。此外，随着粒径的减小，DT、DT 和 DT 中 HMs 的来源变得更加单一，这可能主要是由于粒径效应导致不同来源的 HMs 重新分布。值得注意的是，DT 中的潜在健康风险高于 DT 和 DT。工业源对健康风险的贡献在 DT 中最高，这主要是由于毒性很强的铬（Cr）所致。本研究强调了在风险评估和污染控制中考虑粒径的重要性，可为粉尘中 HMs 污染的精准管理提供理论依据。
