| Title: | Impact of gas/particle partitioning of semivolatile organic compounds on source apportionment with positive matrix factorization |
| Author(s): | Xie M; Hannigan MP; Barsanti KC; |
| Address: | "Department of Mechanical Engineering, College of Engineering and Applied Science, University of Colorado , Boulder, Colorado 80309, United States" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "To quantify and minimize the influence of gas/particle (G/P) partitioning on receptor-based source apportionment using particle-phase semivolatile organic compound (SVOC) data, positive matrix factorization (PMF) coupled with a bootstrap technique was applied to three data sets mainly composed of 'measured-total' (measured particle- + gas-phase), 'particle-only' (measured particle-phase) and 'predicted-total' (measured particle-phase + predicted gas-phase) SVOCs to apportion carbonaceous aerosols. Particle- (PM2.5) and gas-phase SVOCs were collected using quartz fiber filters followed by PUF/XAD-4/PUF adsorbents and measured using gas chromatography-mass spectrometry (GC-MS). Concentrations of gas-phase SVOCs were also predicted from their particle-phase concentrations using absorptive partitioning theory. Five factors were resolved for each data set, and the factor profiles were generally consistent across the three PMF solutions. Using a previous source apportionment study at the same receptor site, those five factors were linked to summertime biogenic emissions (odd n-alkane factor), unburned fossil fuels (light SVOC factor), road dust and/or cooking (n-alkane factor), motor vehicle emissions (PAH factor), and lubricating oil combustion (sterane factor). The 'measured-total' solution was least influenced by G/P partitioning and used as reference. Two out of the five factors (odd n-alkane and PAH factors) exhibited consistent contributions for 'particle-only' vs 'measured-total' and 'predicted-total' vs 'measured-total' solutions. Factor contributions of light SVOC and n-alkane factors were more consistent for 'predicted-total' vs 'measured-total' than 'particle-only' vs 'measured-total' solutions. The remaining factor (sterane factor) underestimated the contribution by around 50% from both 'particle-only' and 'predicted-total' solutions. The results of this study confirm that when measured gas-phase SVOCs are not available, 'predicted-total' SVOCs should be used to decrease the influence of G/P partitioning on receptor-based source apportionment" |
| Keywords: | Aerosols Air Pollutants/*analysis Alkanes/analysis Cooking Dust Environmental Monitoring Fossil Fuels Gas Chromatography-Mass Spectrometry Polycyclic Aromatic Hydrocarbons/analysis Vehicle Emissions Volatile Organic Compounds/*analysis; |
| Notes: | "MedlineXie, Mingjie Hannigan, Michael P Barsanti, Kelley C eng 2014/08/02 Environ Sci Technol. 2014 Aug 19; 48(16):9053-60. doi: 10.1021/es5022262. Epub 2014 Aug 8" |
