To better understand the impact of dust storm (DS) events on the ambient aerosol organic composition in Seoul, samples of solvent-extractable organic compounds in the atmospheric particulate matter with an aerodynamic diameter of less than or equal to a nominal 10 μm (PM10) were collected for 3 months (March-May) in 2007 and characterized. The results of the statistical analysis suggested that during the DS events the ambient PM10 concentration increased, the n-alkanes concentrations decreased, and the PAH concentrations show no trend, although they increased slightly. The distributions of n-alkanes and PAH species showed that among n-alkanes only C25 and C27 species in the non-DS samples increased compared to in the DS samples. Since C25 and C27 species are mainly emitted from plants, this suggests that the impact of biogenic emissions of n-alkanes was reduced during the DS periods. Among PAHs, only the concentration of Fluoranthene increased in a statistically significant manner during the DS period, and only the 1,3,5-Triphenylbenzene level was higher during the non-DS period. The backward trajectory analysis results showed that the air parcels over Seoul did not show much difference between DS and non-DS days. The average level of n-alkanes per unit mass of PM10 was statistically lower in the DS samples, while those of the PAHs showed no statistically significant differences between the DS and non-DS samples.
- Air mass backward trajectory analysis
- Dust storm event
- Organic aerosols