| Title: | Indoor secondary organic aerosols: Towards an improved representation of their formation and composition in models |
| Author(s): | Kruza M; McFiggans G; Waring MS; Wells JR; Carslaw N; |
| Address: | "Department of Environment and Geography, University of York, Wentworth Way, York, YO10 5NG, UK. School of Earth and Environmental Sciences, University of Manchester, Manchester, UK. Department of Civil, Architectural and Environmental Engineering, Drexel University, Philadelphia, PA, USA. National Institute for Occupational Safety and Health, Morgantown, WV, USA" |
| DOI: | 10.1016/j.atmosenv.2020.117784 |
| ISSN/ISBN: | 2590-1621 (Electronic) 2590-1621 (Linking) |
| Abstract: | "The formation of secondary organic aerosol (SOA) indoors is one of the many consequences of the rich and complex chemistry that occurs therein. Given particulate matter has well documented health effects, we need to understand the mechanism for SOA formation indoors and its resulting composition. This study evaluates some uncertainties that exist in quantifying gas-to-particle partitioning of SOA-forming compounds using an indoor detailed chemical model. In particular, we investigate the impacts of using different methods to estimate compound vapour pressures as well as simulating the formation of highly oxygenated organic molecules (HOM) via auto-oxidation on SOA formation indoors. Estimation of vapour pressures for 136 alpha-pinene oxidation species by six investigated methods led to standard deviations of 28-216%. Inclusion of HOM formation improved model performance across three of the six assessed vapour pressure estimation methods when comparing against experimental data, particularly when the NO(2) concentration was relatively high. We also explored the predicted SOA composition using two product classification methods, the first assuming the molecule is dominated by one functionality according to its name, and the second accounting for the fractional weighting of each functional group within a molecule. The SOA composition was dominated by the HOM species when the NO(2)-to-alpha-terpineol ratio was high for both product classification methods, as these conditions promoted formation of the nitrate radical and hence formation of HOM monomers. As the NO(2)-to-alpha-terpineol ratio decreased, peroxides and acids dominated the simple classification, whereas for the fractional classification, carbonyl and alcohol groups became more important" |
| Keywords: | Highly oxygenated organic molecules Indoor air chemistry Secondary organic aerosol Vapour pressure Volatile organic compound; |
| Notes: | "PubMed-not-MEDLINEKruza, M McFiggans, G Waring, M S Wells, J R Carslaw, N eng CC999999/ImCDC/Intramural CDC HHS/ England 2021/02/18 Atmos Environ X. 2020 Nov; 240:10.1016/j.atmosenv.2020.117784. doi: 10.1016/j.atmosenv.2020.117784" |
