State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research, Tianjin 300350, China.
Environ Int. 2022 Jun;164:107236. doi: 10.1016/j.envint.2022.107236. Epub 2022 Apr 15.
Accurate measurements of PM related heavy metals (HMs) and some components are critical to better understanding the sources and health risks of PM. HMs and other components in PM were simultaneously measured using online and offline filter-based methods in a Chinese megacity. Online Mn, Pb, Cu, and Zn concentrations exhibited good correspondence with offline results (R ≥ 0.7, relative biases = -3%-22%). Some differences were observed for Cr, As, Co, and V. The assessment of online and offline probabilistic health risks indicated that non-cancer and total cancer risks were higher than the acceptable limits. Different analytical methods of As may result in different uncertainties in risk analysis. The positive matrix factorization model (PMF) was used to perform online and offline source apportionment. Five sources (coal combustion, vehicle source, industrial source, secondary source, and resuspended dust) were identified. Lower online percentage contribution of resuspended dust (8%) might relate to the lack of Si and Al measurements. The different rate contributions of vehicle source were potentially linked to the different time resolutions of the online and offline data. The assessment of online and offline source-specific health risks revealed that industrial source and coal combustion were the most important sources. Online and offline source-specific risks were not significantly different (P > 0.05). This contrastive study not only helps decision makers to manage health risk more effectively, but also provides insights into the applicability of online and offline measurements for quantifying source-specific risks.
准确测量与 PM 相关的重金属 (HMs) 和某些成分对于更好地了解 PM 的来源和健康风险至关重要。本研究采用在线和离线基于滤膜的方法同时测量了中国特大城市 PM 中的 HMs 和其他成分。在线测量的 Mn、Pb、Cu 和 Zn 浓度与离线结果具有良好的一致性（R≥0.7，相对偏差=-3%-22%）。Cr、As、Co 和 V 的结果则存在一定差异。在线和离线概率健康风险评估表明，非癌症和总癌症风险均高于可接受限值。不同的 As 分析方法可能会导致风险分析中的不确定性不同。采用正定矩阵因子模型（PMF）对在线和离线源解析。共识别出 5 个源（煤燃烧、机动车源、工业源、二次源和扬尘）。在线测量的扬尘贡献比例较低（8%）可能与 Si 和 Al 测量的缺失有关。在线和离线数据时间分辨率不同，可能导致机动车源的贡献率存在差异。在线和离线源特定健康风险评估显示，工业源和煤燃烧是最重要的污染源。在线和离线源特定风险无显著差异（P＞0.05）。这项对比研究不仅有助于决策者更有效地管理健康风险，还为定量源特定风险的在线和离线测量的适用性提供了新的见解。
