Title: | Mobile Sources Are Still an Important Source of Secondary Organic Aerosol and Fine Particulate Matter in the Los Angeles Region |
Author(s): | Zhao Y; Tkacik DS; May AA; Donahue NM; Robinson AL; |
Address: | "Center for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States. Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States. Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States. Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
Abstract: | "Secondary organic aerosol (SOA) is a significant component of atmospheric fine particulate matter. Mobile sources have historically been a major source of SOA precursors in urban environments, but decades of regulations have reduced their emissions. Less regulated sources, such as volatile chemical products (VCPs), are of growing importance. We analyzed ambient and emissions data to assess the contribution of mobile sources to SOA formation in Los Angeles during the period of 2009-2019. During this period, air quality in the Los Angeles region has improved, but organic aerosol (OA) concentrations did not decrease as much as primary pollutants. This appears to be largely due to SOA, whose mass fraction in OA increased over this period. In 2010, about half of the freshly formed SOA measured in Pasadena, CA appears to be formed from hydrocarbon (non-oxygenated) precursors. Chemical mass balance analysis indicates that these hydrocarbon SOA precursors (including intermediate volatility organic compounds) can largely be explained by emissions from mobile sources in 2010. Our analysis indicates that continued reduction in emissions from mobile sources should lead to additional significant decreases in atmospheric SOA and PM(2.5) mass in the Los Angeles region" |
Keywords: | Particulate Matter/analysis *Air Pollutants/analysis Los Angeles Aerosols/chemistry *Air Pollution/analysis Vehicle Emissions/analysis Environmental Monitoring air pollution consumer products emissions hydrocarbon precursors secondary organic aerosol; |
Notes: | "MedlineZhao, Yunliang Tkacik, Daniel S May, Andrew A Donahue, Neil M Robinson, Allen L eng Research Support, U.S. Gov't, Non-P.H.S. 2022/10/11 Environ Sci Technol. 2022 Nov 15; 56(22):15328-15336. doi: 10.1021/acs.est.2c03317. Epub 2022 Oct 10" |