Abstract
Better understanding of fine particulate matter (PM2.5) composition and sources associated with brown carbon (BrC) and reactive oxygen species (ROS) are essential for developing effective air quality control strategies to mitigate climate warming and protect human health. To identify the common chemical composition and sources associated with BrC and ROS, BrC light absorption and hydroxyl radical (·OH), one of the most reactive ROS, were measured for the same batch of filter samples collected in Beijing, China during a winter sampling period covering days with different pollution levels, together with detailed chemical composition analysis, including major components and individual organic and inorganic source-specific tracers. The results showed that both light absorption of BrC and ·OH generation by per mass PM2.5 decreased with increase of PM2.5 mass concentrations, which could be primarily attributed to the predominant roles played by secondary inorganic aerosols in the increased PM2.5 mass, while both of them increased with the fractions of water-soluble organic carbon (WSOC) in PM2.5. WSOC and combustion-related sources were found to be the common and major contributors to both BrC and ·OH generation in Beijing winter. However, BrC exhibited better correlations with fossil source WSOC, while ·OH better correlated with biomass burning source related WSOC. During the study period, fossil sources especially coal combustion were more important sources for BrC, while biomass burning played a relatively stronger role in ·OH generation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.