Source Apportionment of Near-Road Atmospheric Aerosols in Ontario, California

BRADLEY RIES, Yifan Ding, Mohammad Sowlat, Payam Pakbin, Akula Venkatram, Roya Bahreini, University of California, Riverside

     Abstract Number: 467
     Working Group: Source Apportionment

Abstract
Direct tailpipe emissions from vehicles in urban environments have reached an all-time low. Because of this, emissions from sources other than the exhaust-such as brake wear, tire wear, and particles resuspended from the roadway itself, are gaining more importance. To study the contribution of these sources to atmospheric aerosols in the Inland Empire of Southern California, we deployed an Xact® 625i Ambient Continuous Multi-Metals Monitor (with an alternating PM_2.5 and PM₁₀ inlet) and Portable Environmental Beta-Attenuation Mass Monitors (E-BAM), one with a PM2.5 and one with a PM10 inlet, at a near-road air monitoring station in Ontario, managed by the South Coast Air Quality Management District. Meteorological parameters and concentrations of NOx, CO, and black carbon, and total particle number (PN) were also measured using Teledyne T200, Horiba APMA 370, Magee AE33 and Teledyne API 651. We will use positive matrix factorization (EPA v 5.0) to determine the contributions of the tail-pipe and non-tailpipe emissions to overall PM_2.5 and PM₁₀ concentrations. Local meteorology as well as diurnal profiles of the measured species and those of the resolved factors will be discussed.