AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Spatially Resolved Elemental Air Pollution Concentrations in Southern California
SCOTT FRUIN, Fred Lurmann, Ed Avol, University of Southern California
Abstract Number: 388 Working Group: Urban Aerosols
Abstract As part of the Southern California Children’s Health Study, a longitudinal study of children’s respiratory health, we conducted an ambitious particulate sampling campaign to investigate the near-source, within-community spatial variation in particulate air pollution due to traffic sources. 30 sites per community (24 residences, 5 schools, and an existing central site monitor) were selected to capture high and low predicted traffic emissions impacts from arterial roads and freeways, respectively, using the CALINE line source dispersion model. We used four cascade impactors at each site to collect three PM sizes, <0.2, 0.2 to 2.5, and 2.5 to 10 um, along with NO2 and NOx via passive monitors. Samples were collected during two consecutive 2-week sampling periods, in each of two seasons. Elemental analyses included elemental and organic carbon (EC/OC), total and water soluble elements, water soluble organics (WSOC), ions, and nitrate. Primary pollutants such as NO, EC0.2, EC2.5 and copper (form brake wear) showed the largest differences by predicted traffic impact while PM2.5 or WSOC, pollutants with significant contributions from photochemistry, showed little or no traffic impact pattern. Traffic impacts were also more distinct in the cool season (Oct 1 through Mar 31). Principal components analysis (PCA) of the elemental concentrations showed correlated clusters of elements indicative of brake wear (Cu, Ba, Sb) and catalytic converters (Pt, Rh) in the fine and coarse size fractions PCA also showed clusters indicative of regional scale ship emissions (S, V, Ni) and sea salt (Na).