Chen Mei-Juan, Qian Zi-He, Gu Chen-Juan, Zhang Shu-Meng, Liu Zhi-Yi, Wang Xin-Feng, Ge Xin-Lei
School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, China.
Environment Research Institute, Shandong University, Qingdao 266237, China.
Huan Jing Ke Xue. 2022 Apr 8;43(4):1738-1746. doi: 10.13227/j.hjkx.202108106.
Nitrated phenols are a group of nitrogen-containing organics ubiquitously present in ambient air, which are also important components of atmospheric light-absorbing organic matter (brown carbon) that have significant impacts on climate change, air quality, and human health. In this study, we collected a total of 265 daily filter samples of fine particles (PM) in northern suburban Nanjing from March 2019 to January 2020. We used ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) to detect and quantify eight nitrated phenolic species. The results showed that the average annual concentration of total nitrated phenols in the sampling site was 18.77 ng·m, and the average concentrations in spring, summer, autumn, and winter were 16.82, 8.59, 17.28, and 44.79 ng·m, respectively. Such concentrations were obviously higher than those determined in other countries but were similar to those in domestic cities, such as Jinan. 4-Nitrophenol was the most abundant nitrated phenol, followed by 4-nitrocatechol and 2-methoxy-5-nitrophenol. Correlation analysis showed that 3-nitrosalicylic acid was from a specific source different from that of other species. Finally, we used a positive matrix factorization model to quantify the source contributions of nitrated phenols. The major sources were vehicle emissions (32%), mixed coal and biomass burning emissions (44%), and industrial emissions (24%). The mixed coal and biomass burning emissions were dominant in autumn and winter. The mass fraction of 3-nitrosalicylic acid in the factor of industrial emissions was>90%, consistent with the results of the correlation analysis. Overall, this study provides valuable insights into the understanding of concentrations, characteristics, and sources of atmospheric nitrated phenols in ambient air.
硝基酚是一类普遍存在于环境空气中的含氮有机物，也是大气吸光有机物（棕碳）的重要组成部分，对气候变化、空气质量和人类健康有着重大影响。在本研究中，我们于2019年3月至2020年1月在南京北郊共采集了265个细颗粒物（PM）的每日滤膜样本。我们使用超高效液相色谱 - 质谱联用仪（UHPLC - MS）检测并定量了8种硝基酚类物质。结果表明，采样点总硝基酚的年均浓度为18.77 ng·m ，春季、夏季、秋季和冬季的平均浓度分别为16.82、8.59、17.28和44.79 ng·m 。这些浓度明显高于其他国家测定的浓度，但与国内城市如济南的浓度相似。4 - 硝基酚是含量最高的硝基酚，其次是4 - 硝基邻苯二酚和2 - 甲氧基 - 5 - 硝基酚。相关性分析表明，3 - 硝基水杨酸来自与其他物种不同的特定来源。最后，我们使用正矩阵因子分解模型来量化硝基酚的源贡献。主要来源是车辆排放（32%）、煤炭与生物质混合燃烧排放（44%）和工业排放（24%）。煤炭与生物质混合燃烧排放在秋季和冬季占主导。工业排放因子中3 - 硝基水杨酸的质量分数>90%，与相关性分析结果一致。总体而言，本研究为了解环境空气中大气硝基酚的浓度、特征和来源提供了有价值的见解。
