State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, No. 19, Xinjiekouwai Street, Beijing, 100875, China.
Environ Sci Pollut Res Int. 2022 Oct;29(50):75471-75486. doi: 10.1007/s11356-022-21060-w. Epub 2022 Jun 2.
To analyze the impact of particle sizes on sources and related health risks for heavy metals, road dust samples in Beijing were collected and sifted into five particle sizes. The positive matrix factorization (PMF), human health risk assessment model (HHRA), and Monte Carlo simulation were used in the health risk assessment and source apportionment. Results showed that mass of particles < 74 μm occupied about 50% of the total particles, while only 8.48% of the particles were > 500 μm. Mass distribution and concentrations of heavy metals in each particle size changed in temporal. Over 85.00% of carcinogenic risks (CR) were from particles <74 μm, whereas CR from particles >250 μm were ignorable. Sources for health risks in each particle size were traffic exhaust, fuel combustion, construction, and use of pesticides and fertilizers. Proportions of sources to CR differed among particle sizes. Traffic exhaust and fuel combustion contributed over 90% to CR in particles <74 μm, whereas construction contributed the highest (31.68-54.14%) among all sources in particles 74-250 μm. Furthermore, the difference between health risks based on sifted road dust and that based on unsifted road dust was quantitatively analyzed. Source-specific health risk apportionment based on unsifted road dust was not presentative to all particle sizes, and true value of health risks could be over 2.5 times of the estimated value based on unsifted road dust, emphasized the importance of sifting of road dust.
为了分析颗粒物粒径对重金属来源及其相关健康风险的影响，采集了北京的道路灰尘样本并筛分成了五个粒径。采用正矩阵因子分解（PMF）、人体健康风险评估模型（HHRA）和蒙特卡罗模拟对健康风险评估和源解析进行了分析。结果表明，粒径<74μm的颗粒物质量约占总颗粒物的 50%，而粒径>500μm的颗粒物仅占 8.48%。每个粒径中重金属的质量分布和浓度随时间变化。超过 85.00%的致癌风险（CR）来自粒径<74μm的颗粒物，而粒径>250μm的颗粒物的 CR 可以忽略不计。每个粒径中健康风险的来源分别是交通尾气、燃料燃烧、建筑施工以及农药化肥的使用。不同粒径的源对 CR 的贡献比例不同。交通尾气和燃料燃烧对粒径<74μm的颗粒物中的 CR 贡献超过 90%，而建筑施工对粒径 74-250μm 的颗粒物中 CR 的贡献最高（31.68-54.14%）。此外，还定量分析了基于筛分道路灰尘和未筛分道路灰尘的健康风险之间的差异。基于未筛分道路灰尘的源特定健康风险分配对所有粒径均不具有代表性，真实的健康风险值可能是基于未筛分道路灰尘的估计值的 2.5 倍以上，这强调了筛分道路灰尘的重要性。
