Water-soluble trace and rare earth elements in Artic aerosol as tracer of different sources

The elemental composition of water-soluble size-fractionated airborne particulate matter was investigated in order to better understand the distribution of water-soluble fraction of trace elements (TE) and of rare earth elements (REE) among different particulate sizes. Samples were collected at a polar station in the Svalbard Islands (78 55 07 N, 11 53 30E) from 19 April to 14 September 2010. A five-sta ge high volume cascade impactor Model TE-235 equipped with a TE-6070 PM10 size selective head (Tisch Environmental Inc.) was used at a flow rate of 68m3 h-1. This sampler allows the collection of five size classes ofairborne particles (aerodynamic diameter ranges of 10-7.2 ?m, 7.2-3.0 ?m, 3.0-1.5 ?m, 1.5-0.95 ?m, 0.95-0.49 ?m), plus particles smaller than 0.49 ?m collected by a background filter. Sample collection, treatment, and area are reported in two previous papers (Scalabrin et al., 2012; Zangrando et al., 2013). Analyses were carried out using a Sector Field Inductively Coupled Plasma- Mass Spectrometer (SF-ICP-MS, Element2 Finnigan-MAT, Bremen, Germany), coupled with a fully-integrated inlet system (Apex, AHF analysentechnik, Tubingen, Germany), on acidified samples (ultrapure nitric acid, Romil®UPA, Cambridge, UK). TE and REE were measured in water-soluble fractions with the aim of recognising reliable tracers of specific sources which may prove crucial to cost-effective strategies of air pollution control. Water-soluble trace metals and elements were exploited as tracers to identify such individual sources. The use of water-soluble elements helps us to consider only the anthropogenic components of PM (Birmili et al., 2006; Fernández-Espinosa et al., 2004; Song et al., 2001). The trace element content of aerosols sampled in the most remote areas of our planet, primarily due to long range transport, gives valuable information on the global transport of particulates and on the contribution of human activities to air pollution