Ambient volatile organic compounds at a receptor site in the Pearl River Delta region: Variations, source apportionment and effects on ozone formation

Yao Meng; Junwei Song; Lewei Zeng; Yingyi Zhang; Yan Zhao; Xufei Liu; Hai Guo; Liuju Zhong; Yubo Ou; Yan Zhou; Tao Zhang; Dingli Yue; Senchao Lai

doi:10.1016/j.jes.2021.02.024

Ambient volatile organic compounds at a receptor site in the Pearl River Delta region: Variations, source apportionment and effects on ozone formation

J Environ Sci (China). 2022 Jan:111:104-117. doi: 10.1016/j.jes.2021.02.024. Epub 2021 Mar 23.

Authors

Yao Meng¹, Junwei Song², Lewei Zeng³, Yingyi Zhang¹, Yan Zhao⁴, Xufei Liu³, Hai Guo³, Liuju Zhong⁵, Yubo Ou⁴, Yan Zhou⁴, Tao Zhang⁴, Dingli Yue⁶, Senchao Lai⁷

Affiliations

¹ The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, and Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
² Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen 76344, Germany.
³ Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hong Kong, China.
⁴ Guangdong Environmental Monitoring Center, State Environmental Protection Key Laboratory of Regional Air Quality Monitoring, Guangzhou 510308, China.
⁵ Guangdong Polytechnic of Environmental Protection Engineering, Foshan 528216, China.
⁶ Guangdong Environmental Monitoring Center, State Environmental Protection Key Laboratory of Regional Air Quality Monitoring, Guangzhou 510308, China. Electronic address: dingliyue@163.com.
⁷ The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, and Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China. Electronic address: sclai@scut.edu.cn.

PMID: 34949340
DOI: 10.1016/j.jes.2021.02.024

Abstract

We present the continuously measurements of volatile organic compounds (VOCs) at a receptor site (Wan Qing Sha, WQS) in the Pearl River Delta (PRD) region from September to November of 2017. The average mixing ratios of total VOCs (TVOCs) was 36.3 ± 27.9 ppbv with the dominant contribution from alkanes (55.5%), followed by aromatics (33.3%). The diurnal variation of TVOCs showed a strong photochemical consumption during daytime, resulting in the formation of ozone (O₃). Five VOC sources were resolved by the positive matrix factorization (PMF) model, including solvent usage (28.6%), liquid petroleum gas (LPG) usage (24.4%), vehicle exhaust (21.0%), industrial emissions (13.2%) and gasoline evaporation (12.9%). The regional transport air masses from the upwind cities of south China can result in the elevated concentrations of TVOCs. Low ratios of TVOCs/NO_x (1.53 ± 0.88) suggested that the O₃ formation regime at WQS site was VOC-limited, which also confirmed by a photochemical box model with the master chemical mechanism (PBM-MCM). Furthermore, the observation on high-O₃ episode days revealed that frequent O₃ outbreaks at WQS were mainly caused by the regional transport of anthropogenic VOCs especially for aromatics and the subsequent photochemical reactions. This study provides valuable information for policymakers to propose the effective control strategies on photochemical pollution in a regional perspective.

Keywords: Ozone (O(3)); Pearl River Delta (PRD) region; Regional transport; Source apportionment; Volatile organic compounds (VOCs).

MeSH terms

Air Pollutants* / analysis
China
Environmental Monitoring
Ozone* / analysis
Vehicle Emissions / analysis
Volatile Organic Compounds* / analysis

Substances

Air Pollutants
Vehicle Emissions
Volatile Organic Compounds
Ozone