HR: 17:45h
AN: A54A-08    [Abstracts]
TI: Lubricating Oil and Fuel Contributions to Particulate Matter Emissions From Light Duty Gasoline and Heavy Duty Diesel Vehicles
AU: * Kleeman, M
EM: mjkleeman@ucdavis.edu
AF: UC Davis Department of Civil and Environmental Engineering, 1 Shields Ave, Davis, CA 95616, United States
AU: Riddle, S
EM: sgriddle@ucdavis.edu
AF: UC Davis Department of Chemistry, 1 Shields Ave, Davis, CA 95616, United States
AU: Robert, M
EM: marobert@ucdavis.edu
AF: UC Davis Department of Civil and Environmental Engineering, 1 Shields Ave, Davis, CA 95616, United States
AU: Jakober, C
EM: cajakober@ucdavis.edu
AF: UC Davis Agriculture and Environmental Chemistry Grad Group, 1 Shields Ave, Davis, CA 95616, United States
AB: Size-resolved particulate matter emissions from heavy duty diesel vehicles (HDDVs) and light duty gasoline vehicles (LDGVs) operated under realistic driving cycles were analyzed for elemental carbon (EC), organic carbon (OC), hopanes, steranes, and polycyclic aromatic hydrocarbons (PAHs). Measured hopane and sterane size distributions did not match the total carbon size distribution in most cases, suggesting that lubricating oil was not the dominant source of particulate carbon in the vehicle exhaust. Regression analysis using 17α(H)- 21β(H)-29-norhopane as a tracer for lubricating oil and benzo[ghi]perylene as a tracer for gasoline showed that gasoline fuel and lubricating oil both make significant contributions to particulate EC and OC emissions from LDGVs. A similar regression analysis performed using 17α(H)-21β(H)-29-norhopane as a tracer for lubricating oil and flouranthene as a tracer for diesel fuel was able to explain the size distribution of particulate EC and OC emissions from HDDVs. The size- and composition-resolved analysis showed that EC emitted from all diesel vehicles operated under relatively high load conditions was dominated by diesel fuel contributions with little EC attributed to lubricating oil. Particulate OC emitted from diesel vehicles was more evenly apportioned between fuel and oil contributions. EC emitted from LDGVs operated under fuel-rich conditions was dominated by gasoline fuel contributions. OC emitted from visibly smoking LDGVs was mostly associated with lubricating oil, but OC emitted from all other categories of LDGVs was dominated by gasoline fuel. The results of the current study clearly illustrate that fuel and lubricating oil make separate and distinct contributions to particulate matter emissions from motor vehicles. These particles should be tracked separately during ambient source apportionment studies since the atmospheric evolution and ultimate health effects of these particles may be different. The source profiles for fuel and lubricating oil contributions to EC and OC emissions derived in this study provide a foundation for future ambient source apportionment calculations.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting