ARB Research Seminar
This page updated June 19, 2013
The DOE Gasoline/Diesel PM Split Study
Eric M. Fujita, Ph.D., Desert Research Institute, Douglas R. Lawson, Ph.D., National Renewable Energy Laboratory, James Schauer, University of Wisconsin-Madison
September 07, 2005
Cal EPA Headquarters, 1001 "I" Street, Sacramento, CA
DOE's Gasoline/Diesel PM Split Study was conducted to quantify the relative contributions of tailpipe emissions from gasoline-powered motor vehicles and diesel-powered motor vehicles to the ambient concentrations of fine particulate matter (PM2.5) in the urbanized region of Southern California using an organic compound-based chemical mass balance model (CMB). This study involved several groups working cooperatively on sample collection and quality assurance aspects of the study, but working independently, at least initially, on chemical analysis and data analysis. Groups participating in the Study included California's Bureau of Automotive Repair, South Coast Air Quality Management District, U.S. Environmental Protection Agency, Ralph's Groceries, Clean Air Vehicle Technology Center, West Virginia University, the University of Wisconsin at Madison (UWM), and the Desert Research Institute (DRI). Source testing of 59 LD vehicles (including 2 diesel vehicles) was completed in June 2001; ambient measurements were performed in July 2001, and the testing of 34 HD vehicles was completed in September 2001. Source and ambient samples were collected in parallel by DRI and UWM. The presentation will describe the chemical compositions and apportionments of gasoline- and diesel-powered vehicles that were obtained by DRI and UWM.
Twenty-four hour ambient samples were collected on Teflon and quartz filters and Teflon-impregnated glass fiber (TIGF) filters followed by polyurethane foam (PUF) plugs and XAD-4 resin cartridges for twenty-eight consecutive days at air monitoring stations in downtown Los Angeles and Azusa. Teflon filters were analyzed for gravimetric mass, elements, and ions, and quartz filters were analyzed for organic and elemental carbon by Thermal Optical Reflectance (TOR) and Thermal Optical Transmittance (TOT) using both IMPROVE and NIOSH protocols. The TIGF/PUF/XAD samples were combined and extracted together by day of week, and analyzed for polycyclic aromatic hydrocarbons, hopanes, steranes, alkanes, methoxyphenols, lactones, sterols, and polar organic compounds. A third set of ambient samples was collected from a mobile sampling van at several regionally representative sites and at locations with expected higher proportions of PM emissions from diesel trucks (e.g., Terminal Island, truck stop, highway truck routes) and from gasoline vehicles (e.g., congested freeway during commuter rush hour, surface streets during weekends, a parking lot at major sporting events). Black carbon and total particulate matter were monitored continuously by photoacoustic and DustTrak instruments. In addition to the source apportionment effort, we examined the variations in relative abundances of key marker compounds in the source-dominated ambient samples relative to corresponding variations in the samples from regional air quality monitoring sites by day of week. This work was supported by the DOE's Office of FreedomCAR & Vehicle Technologies through the National Renewable Energy Laboratory.
Eric M. Fujita, Ph.D., is a Research Professor in the Division of Atmospheric Sciences of the Desert Research Institute in Reno, Nevada. Dr. Fujita has 25 years of experience in planning and conducting air quality studies. His research interests include chemical characterization of emission sources, reconciliation of emission inventory estimates for VOC and PM with ambient measurements, and measurement and characterization of exposures to toxic air contaminants. Prior to coming to DRI, he was an Air Pollution Research Specialist for the Research Division of the California Air Resources Board where he initiated and managed extramural research in emission inventory development, air quality measurements, and atmospheric processes. Dr. Fujita has a doctorate in Environmental Science and Engineering from the University of California, Los Angeles.
Douglas R. Lawson, Ph.D., is a principal scientist at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, where he is responsible for OHVT's Environmental Science & Health Impacts Program. He coordinates this effort with industry, government, and university groups in understanding the influence of fuels and motor vehicle emissions on air quality in the U.S. Dr. Lawson also currently serves as a commissioner on the nine-member state of Colorado Air Quality Control Commission. He has been a member of two National Academy of Science Committees: one on the Toxicological and Performance Aspects of Oxygenated and Reformulated Motor Vehicle Fuels; and the second, on Effectiveness of Vehicle Emission Inspection and Maintenance Programs. Prior to coming to NREL, he served as senior research scientist at Colorado State University for the Northern Front Range Air Quality Study, a $4 million program designed to identify the sources of the Denver "Brown Cloud." He has been asked to testify at congressional hearings and legislative hearings in several states on various aspects of air pollution and is an expert on various aspects of mobile source pollution. Dr. Lawson worked at the ARB from 1980-1992, where he performed air pollution research and supervised many air pollution research studies, including the 1987 Southern California Air Quality Study, and received ARB's Sustained Superior Performance and Outstanding Supervisory Management Awards. He has authored more than 100 reports on various aspects of air pollution.
James Schauer, Ph.D., is an Associate Professor in the Environmental Chemistry and Technology Program and the Civil and Environmental Engineering Program at the University of Wisconsin-Madison, and serves as the Director of the Water Science and Engineering Laboratory at the University of Wisconsin. He received his Ph.D. in Environmental Engineering Science from the California Institute of Technology, his MS in Environmental Engineering from the University of California at Berkeley and his BS degree in Chemical and Petroleum Refining Engineering from the Colorado School of Mines. Dr. Schauer has previously worked in the chemical and petroleum refining industry as a Chemical Process Engineer and has helped commission and start-up large chemical facilities in Asia, Europe, North America, and Africa. Dr. Schauer currently leads an internationally recognized research team that employs advanced chemical analysis and air pollution sampling techniques to understand the chemical composition of source emissions and atmospheric pollutant concentrations. These methods are being used to understand the origin of impact of air pollutants in the urban atmosphere, human health, the ecosystems, and global climate change. Dr. Schauer has authored and co-authored more than 45 peer reviewed manuscripts in leading environmental science, environmental engineering, and air pollution journals in the past 8 years. Prof. Schauer is honored as a Guest Professor at Peking University (formerly Beijing University) in Beijing, China.