Presence and size distribution of water-soluble organic compounds in the Antarctic aerosol.

The organic fraction is an important part of particulate matter in the atmosphere, and water-soluble Organic compounds (WSOC)constitute between 40 and 60% of organic carbon. WSOC have great environmental importance, as they can reduce the surface tension of aqueous solutions by influencing the hygroscopicity of the aerosol and consequently the particles'ability to act as cloud condensation nuclei (CCN), with consequences on the optical properties of the aerosol, the air quality, and climate. Our scientific activity in Antarctica had the purpose of obtaining further information about the formation, chemical composition and transport processes of aerosols. The study was conducted over 5 campaigns, two of which at the Mario Zucchelli Station (MZS) (29 November 2010-18 January 2011 and 3 November 2004-10 January 2005), two atConcordia Station (Dome C) (19 December 2012- 28 January 2012 and 7 December 2012-26 January 2013), and during an oceanographic cruise on the Ross Sea (13 January -19 February) 2012. The Arctic aerosol samples were collected using a high volume sampler PM10 TE- 6070, equipped with a 5-stage cascade impactor Model TE -235.The 6 aerosols fractions collected ranged between 10.0 and < 0.49?m at the Antarctic bases of MZS and Dome C. During the oceanographic cruise, atmospheric particulate matter (Total Suspended Particles,TSP) was collected using a TE5000 High Volume Air sampler (both samplers are produced by Tisch Environmental Inc., Cleves, OH). In the aerosols samples, we determined the levels and particle size presence of the following compounds: levoglucosan and methoxyphenols (vanillic acid,isovanillic acid, homovanillic acid, syringic acid, coniferil aldehyde, ferulic acid, syringaldehyde, p-coumaric acid, vanillin), as biomass burning markers and 36 amino acids as indicators of primary production.