PM2.5 characterization for time series studies: Organic molecular marker speciation methods and observations from daily measurements in Denver |
| |
| Authors: | Steven J Dutton Daniel E Williams Jessica K Garcia Sverre Vedal Michael P Hannigan |
| |
| Institution: | 1. Key Lab of Aerosol Chemistry & Physics, Institute of Earth Environment, Chinese Academy of Sciences, Xi''an, China;2. State Key Lab of Loess and Quaternary Geology (SKLLQG), Institute of Earth Environment, Chinese Academy of Sciences, Xi''an, China;3. Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, United States;4. South China of Institute of Environmental Sciences, SCIES, Guangzhou, China;5. Institute of Global Environmental Change, Xi''an Jiaotong University, Xi''an, China;6. Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland;1. Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences (CAS), Beijing 100101, China;2. State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, CAS, Lanzhou 730000, China;3. Emory University, Atlanta, Georgia (GA), United States;4. Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221005, India;5. China National Environmental Monitoring Center, Beijing 100012, China;6. Chubu Institute for Advanced Studies, Chubu University, Kasugai 487-8501, Japan;7. CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing 100101, China;8. University of Chinese Academy of Sciences, Beijing 100049, China;9. Institute of Surface-Earth System, Tianjin University, Tianjin 300072, China |
| |
| Abstract: | Particulate matter less than 2.5 microns in diameter (PM2.5) has been shown to have a wide range of adverse health effects and consequently is regulated in accordance with the US-EPA's National Ambient Air Quality Standards. PM2.5 originates from multiple primary sources and is also formed through secondary processes in the atmosphere. It is plausible that some sources form PM2.5 that is more toxic than PM2.5 from other sources. Identifying the responsible sources could provide insight into the biological mechanisms causing the observed health effects and provide a more efficient approach to regulation. This is the goal of the Denver Aerosol Sources and Health (DASH) study, a multi-year PM2.5 source apportionment and health study.The first step in apportioning the PM2.5 to different sources is to determine the chemical make-up of the PM2.5. This paper presents the methodology used during the DASH study for organic speciation of PM2.5. Specifically, methods are covered for solvent extraction of non-polar and semi-polar organic molecular markers using gas chromatography–mass spectrometry (GC–MS). Vast reductions in detection limits were obtained through the use of a programmable temperature vaporization (PTV) inlet along with other method improvements. Results are presented for the first 1.5 years of the DASH study revealing seasonal and source-related patterns in the molecular markers and their long-term correlation structure. Preliminary analysis suggests that point sources are not a significant contributor to the organic molecular markers measured at our receptor site. Several motor vehicle emission markers help identify a gasoline/diesel split in the ambient data. Findings show both similarities and differences when compared with other cities where similar measurements and assessments have been made. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
