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JOUR NAL O F E NVI R ONM E NT AL S C I E NC ES 79 (2019 ) 1 – 10
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Sources of methacrolein and methyl vinyl ketone and their
contributions to methylglyoxal and formaldehyde at a receptor
site in Pearl River Delta
3,
4
4,
Zhenhao Ling 1,2 , Zhuoran He 1,2 , Zhe Wang ⁎ , Min Shao , Xuemei Wang ⁎
1. School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, China
2. Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies, Sun Yat-sen University, Guangzhou, China
3. Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong, China
4. Institute for Environmental and Climate Research, Jinan University, Guangzhou, China
AR TIC L E I N F O A BS TR ACT
Article history: Methacrolein (MACR) and methyl vinyl ketone (MVK) are two major intermediate products
Received 7 October 2018 from the photochemical oxidation of isoprene, the most important biogenic volatile organic
Revised 22 November 2018 compound. In addition, MACR and MVK have primary emissions. Investigating the sources
Accepted 6 December 2018 and evolution of MACR and MVK could provide helpful information for the oxidative
Available online 17 December 2018 capacity of the atmosphere. In this study, hourly measurements of isoprene, MACR, and
MVK were conducted at a receptor site in the Pearl River Delta region (PRD), i.e., the Heshan
Keywords: site (HS), from 22 October to 20 November, 2014. The average mixing ratios of isoprene,
Source apportionment MACR and MVK were 151 ± 17, 91 ± 6 and 79 ± 6 pptv, respectively. The daily variations and
Methacrolein the ratios of MVK/MACR during daytime and nighttime suggested that other sources
Methyl vinyl ketone besides isoprene photooxidation influenced the MACR and MVK abundances at the HS.
Pearl River Delta Positive matrix factorization was utilized to resolve the sources of MACR and MVK. Five
sources were identified and quantified, including biogenic emissions, biomass burning,
secondary formation, diesel, and gasoline vehicular emissions. Among them, secondary
formation made the greatest contribution to observed MACR and MVK with average
contributions of ~45% and ~70%, respectively. Through the yields of secondary products
from the oxidation of MACR and MVK by the OH radical and the concentrations of MACR
and MVK, it was found that methylglyoxal and formaldehyde were the main oxidation
products of MACR and MVK at the HS site. Overall, this study evaluated the roles of primary
emissions on ambient levels of MACR and MVK and advanced the understanding of
photochemical oxidation of MACR and MVK in the PRD.
© 2018 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences.
Published by Elsevier B.V.
Introduction Composed by hundreds of species with different photochem-
ical reactivity, VOCs could be emitted from various anthropo-
Volatile organic compounds (VOCs) as important air pollut- genic and biogenic emissions. Biogenic VOCs (BVOCs) account
ants have a significant influence on tropospheric chemistry for about 80% of the global annual emissions of VOCs, which
and have attracted more and more concerns (Guo et al., 2017). have high reactivity and are important precursors of ozone
⁎ Corresponding author. E-mail: z.wang@polyu.edu.hk, (Z. Wang), eeswxm@mail.sysu.edu.cn. (X. Wang).
https://doi.org/10.1016/j.jes.2018.12.001
1001-0742/© 2018 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.