Composition and source apportionments of saccharides in atmospheric particulate matter in Beijing

Based on the newly established high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), the saccharides in PM_2.5 and PM₁₀ in Beijing from 2011-2012 were quantified. Fourteen saccharides were synchronously detected in the aerosols samples in Beijing, which can be divided into three categories, i.e. anhydrosugar, sugar and sugar alcohol. Anhydrosugar, coming from biomass burning, include levoglucosan, mannosan and galactosan. Sugar and sugar alcohol, emitted by the primary biogenic emission, include glucose, fructose, trehalose, arabitol, mannitol, glycerol, threitol, 2-meythltrtols (2-methylthreitol and 2-methylerythrito), xylitol and inositol. The concentrations of monosaccharide anhydrides in summer and autumn were obviously higher than those in spring and winter, while the concentrations of sugar and sugar alcohol in winter were significantly lower than those in other seasons. The results of positive matrix factorization analysis suggested that saccharides compounds in atmospheric PM in Beijing can be derived from biomass burning, suspended soil or dust, isoprene SOA, as well as direct release of airborne fungal spores and pollen.