Abstract View
Strong Association between More-Oxidized Oxygenated Organic Aerosols (MO-OOA) with Cellular Reactive Oxygen Species Production upon Particulate Matter Exposure
FOBANG LIU, Taekyu Joo, Gabriela Saavedra, Dong Gao, Jenna Ditto, Jean Rivera-Rios, Drew Gentner, Rodney J. Weber, Nga Lee Ng, Georgia Institute of Technology
Abstract Number: 290
Working Group: Health-Related Aerosols
Abstract
Health risks associated with exposure to ambient particulate matter (PM) are a major concern around the world. Adverse PM health effects have been proposed to be linked to oxidative stress through the overproduction of reactive oxygen species (ROS). However, the associations between PM components and ROS production are not well understood, especially for organic aerosols (OA), which constitute a substantial fraction of fine PM and comprise hundreds to thousands of compounds. In this study, we collected ambient fine PM at an urban site (Jefferson Street, SEARCH network) in Atlanta, GA, during summer and winter. PM-induced cellular ROS production and oxidative potential (OP) of PM were measured. OA components were identified by high-resolution mass spectrometry (HR-ToF-MS and LC-ESI-Q-ToF). Water-soluble metals (e.g., Fe, Cu, and Mn) were also analyzed. We find a positive nonlinear correlation between cellular ROS with OP determined by two acellular assays. A strong association is observed between more-oxidized oxygenated OA (MO-OOA) and cellular ROS for both summer and winter PM. The contribution of different components to cellular ROS and OP is further evaluated by multivariate linear regression analysis. The results resolve a predominant contribution of MO-OOA to cellular ROS production, while OP could be attributed to metals (i.e., Cu and Mn), MO-OOA, less-oxidized oxygenated OA (LO-OOA), and biomass burning OA (BBOA). Our work highlights an important role of MO-OOA in cellular ROS production upon PM exposure.