Assessing the contribution of open crop straw burning to ground-level ozone and associated health impacts in China and the effectiveness of straw burning bans.

Huang, Ling; Zhu, Yonghui; Liu, Hanqing; Wang, Yangjun; Allen, David T.; Ooi, Maggie Chel Gee; Manomaiphiboon, Kasemsan; Latif, Mohd Talib; Chan, Andy; Li, Li

Abstract

In recent years, ozone pollution in China has been shown to increase in frequency and persistence despite the concentrations of fine particulate matter (PM2.5) decreasing steadily. Open crop straw burning (OCSB) activities are extensive in China and emit large amounts of trace gases during a short period that could lead to elevated ozone concentrations. This study addresses the impacts of OCSB emissions on ground-level ozone concentration and the associated health impact in China. Total VOCs and NOx emissions from OCSB in 2018 were 798.8 Gg and 80.6 Gg, respectively, with high emissions in Northeast China (31.7%) and North China (23.7%). Based on simulations conducted for 2018, OCSB emissions are estimated to contribute up to 0.95 µg/m3 increase in annual averaged maximum daily 8-hour (MDA8) ozone and up to 1.35 µg/m3 for the ozone season average. The significant impact of OCSB emissions on ozone is mainly characterized by localized and episodic (e.g., daily) changes in ozone concentration, up to 20 µg/m3 in North China and Yangtze River Delta region and even more in Northeast China during the burning season. With the implementation of straw burning bans, VOCs and NOx emissions from OCSB dropped substantially by 46.9%, particularly over YRD (76%) and North China (60%). Consequently, reduced OCSB emissions result in an overall decrease in annual averaged MDA8 ozone, and reductions in monthly MDA8 ozone could be over 10 µg/m3 in North China. The number of avoided premature death due to reduced OCSB emissions (considering both PM2.5 and ozone) is estimated to be 6120 (95% Confidence Interval: 5320–6800), with most health benefits gained over east and central China. Our results illustrate the effectiveness of straw burning bans in reducing ozone concentrations at annual and national scales and the substantial ozone impacts from OCSB events at localized and episodic scales.

Citation

HUANG, L., ZHU, Y., LIU, H., WANG, Y., ALLEN, D.T., OOI, M.C.G., MANOMAIPHIBOON, K., LATIF, M.T., CHAN, A. and LI, L. 2023. Assessing the contribution of open crop straw burning to ground-level ozone and associated health impacts in China and the effectiveness of straw burning bans. Environment international [online], 171, article 107710. Available from: https://doi.org/10.1016/j.envint.2022.107710

• Journal Article Type: Article
• Acceptance Date: Dec 19, 2022
• Online Publication Date: Dec 22, 2022
• Publication Date: Jan 31, 2023
• Deposit Date: Jun 30, 2023
• Publicly Available Date: Jul 4, 2023
• Journal: Environment International
• Print ISSN: 0160-4120
• Electronic ISSN: 1873-6750
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 171
• Article Number: 107710
• DOI: https://doi.org/10.1016/j.envint.2022.107710
• Keywords: Open biomass burning; Ground-level ozone; Health impacts; Straw burning bans
• Public URL: https://rgu-repository.worktribe.com/output/1998120
• Additional Information: This article has been published with separate supporting information. This supporting information has been incorporated into a single file on this repository and can be found at the end of the file associated with this output.