Yang Yuhan, Battaglia Michael A, Mohan Magesh Kumaran, Robinson Ellis S, DeCarlo Peter F, Edwards Kasey C, Fang Ting, Kapur Sukriti, Shiraiwa Manabu, Cesler-Maloney Meeta, Simpson William R, Campbell James R, Nenes Athanasios, Mao Jingqiu, Weber Rodney J
School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Department of Environmental Health & Engineering, Johns Hopkins University, Baltimore, Maryland 21218, United States.
ACS EST Air. 2024 Feb 10;1(3):175-187. doi: 10.1021/acsestair.3c00066. eCollection 2024 Mar 8.
The oxidative potential (OP) of outdoor PM in wintertime Fairbanks, Alaska, is investigated and compared to those in wintertime Atlanta and Los Angeles. Approximately 40 filter samples collected in January-February 2022 at a Fairbanks residential site were analyzed for OP utilizing dithiothreitol-depletion (OP) and hydroxyl-generation (OP) assays. The study-average PM mass concentration was 12.8 μg/m, with a 1 h average maximum of 89.0 μg/m. Regression analysis, correlations with source tracers, and contrast between cold and warmer events indicated that OP was mainly sensitive to copper, elemental carbon, and organic aerosol from residential wood burning, and OP to iron and organic aerosol from vehicles. Despite low photochemically-driven oxidation rates, the water-soluble fraction of OP was unusually high at 77%, mainly from wood burning emissions. In contrast to other locations, the Fairbanks average PM mass concentration was higher than Atlanta and Los Angeles, whereas OP in Fairbanks and Atlanta were similar, and Los Angeles had the highest OP and OP. Site differences were observed in OP when normalized by both the volume of air sampled and the particle mass concentration, corresponding to exposure and the intrinsic health-related properties of PM, respectively. The sensitivity of OP assays to specific aerosol components and sources can provide insights beyond the PM mass concentration when assessing air quality.
对阿拉斯加费尔班克斯冬季室外细颗粒物的氧化潜力（OP）进行了研究，并与亚特兰大和洛杉矶冬季的氧化潜力进行了比较。2022年1月至2月在费尔班克斯一个住宅地点采集了约40个滤膜样本，利用二硫苏糖醇消耗法（OP）和羟基生成法（OP）分析了其氧化潜力。研究期间细颗粒物的平均质量浓度为12.8μg/m³，1小时平均最大值为89.0μg/m³。回归分析、与源示踪剂的相关性以及寒冷事件和温暖事件之间的对比表明，OP主要对来自住宅木材燃烧的铜、元素碳和有机气溶胶敏感，而OP对来自车辆的铁和有机气溶胶敏感。尽管光化学驱动的氧化速率较低，但OP的水溶性部分异常高，达到77%，主要来自木材燃烧排放。与其他地点不同，费尔班克斯的细颗粒物平均质量浓度高于亚特兰大和洛杉矶，而费尔班克斯和亚特兰大的OP相似，洛杉矶的OP和OP最高。当分别按采样空气体积和颗粒物质量浓度进行归一化时，在OP方面观察到了地点差异，分别对应于暴露情况和细颗粒物与健康相关的内在特性。在评估空气质量时，OP测定法对特定气溶胶成分和来源的敏感性可以提供超出细颗粒物质量浓度的见解。
