| Title: | Global review of source apportionment of volatile organic compounds based on highly time-resolved data from 2015 to 2021 |
| Author(s): | Yang Y; Liu B; Hua J; Yang T; Dai Q; Wu J; Feng Y; Hopke PK; |
| Address: | "State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control & Tianjin Key Laboratory of Urban Transport Emission Research, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research, Tianjin 300350, China. State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control & Tianjin Key Laboratory of Urban Transport Emission Research, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China; CMA-NKU Cooperative Laboratory for Atmospheric Environment-Health Research, Tianjin 300350, China. Electronic address: lbsnankai@foxmail.com. Tianjin Ecology and Environment Bureau, Tianjin 300191, China. Department of Public Health Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA; Institute for a Sustainable Environment, Clarkson University, Potsdam, NY 13699, USA" |
| DOI: | 10.1016/j.envint.2022.107330 |
| ISSN/ISBN: | 1873-6750 (Electronic) 0160-4120 (Linking) |
| Abstract: | "Highly time-resolved data for volatile organic compounds (VOCs) can now be monitored. Source analyses of such high time-resolved concentrations provides key information for controlling VOC emissions. This work reviewed the literature on VOCs source analyses published from 2015 to 2021, and assesses the state-of-the-art and the existing issues with these studies. Gas chromatography system and direct-inlet mass spectrometry are the main monitoring tools. Quality control (QC) of the monitoring process is critical prior to analysis. QC includes inspection and replacement of instrument consumables, calibration curve corrections, and reviewing the data. Approximately 54% published papers lacked details on the quantitative evaluation of the effectiveness of QC measures. Among the reviewed works, the number of monitored species varied from 5 to 119, and fraction of papers with more than 90 monitored species increased yearly. US EPA PMF v5.0 was the most commonly used ( approximately 86%) for VOC source analyses. However, conventional source apportionment directly uses the measured VOCs and may be problematic given the impacts of dispersion and photochemical losses, uncertainty setting of VOCs data, factor resolution, and factor identification. Excluding species with high-reactivity or estimation of corrected concentrations were often applied to reduce the influence of photochemical reactions on the results. However, most reports did not specify the selection criteria or the specific error fraction values in the uncertainty estimation. Model diagnostic indexes were used in 99% of the reports for PMF analysis to determine the factor resolution. Due to lack of known local source profiles, factor identification was mainly achieved using marker species and characteristic species ratios. However, multiple sources had high-collinearity and the same species were often used to identify different sources. Vehicle emissions and fuel evaporation were the primary contributors to VOCs around the world. Contribution of coal combustion in China was substantially higher than in other countries" |
| Keywords: | *Air Pollutants/analysis China Environmental Monitoring/methods United States United States Environmental Protection Agency Vehicle Emissions/analysis *Volatile Organic Compounds/analysis High-time resolution Methods Monitoring instruments Source apportio; |
| Notes: | "MedlineYang, Yang Liu, Baoshuang Hua, Jing Yang, Tao Dai, Qili Wu, Jianhui Feng, Yinchang Hopke, Philip K eng Research Support, Non-U.S. Gov't Review Netherlands 2022/06/08 Environ Int. 2022 Jul; 165:107330. doi: 10.1016/j.envint.2022.107330. Epub 2022 May 31" |
