Chemical Composition of Aerosol Size Fractions at a Coastal Site in Southwestern Italy: Seasonal Variability and Transport Influence.

The present study focuses on the elemental characteriza- tion of fine and coarse particles collected at a coastal site of southwestern Italy, in a suburban area of the Calabria region. A chemical tracer analysis was carried out to iden- tify the major emission sources influencing on the atmo- spheric aerosol levels. Size-resolved particulate samples were collected during three 2-week seasonal sampling cam- paigns: autumn (19 October to 2 November 2003), winter (19 January to 2 February 2004) and spring (26 April to 10 May 2004). Ambient concentrations of selected elements (Fe, Mn, Mg, Ca, V, Cu, Cr, Ni, Zn, Pb, and Cd) associated to fine and coarse size fractions were determined using atomic absorption spectrometry (AAS). The enrichment factor method was applied, suggesting a prevailing anthropo- genic component for all the detected elements, with Fe, Mg, Mn, and Ca as exceptions. Trajectory sector analysis was used in order to discriminate the influence of different air mass origins and paths. Long-range transport from both the continental Europe and the Saharan region proved to be the main influencing factors. African dust outbreaks, whose occurrence frequency was greater during the autumn and spring seasonal monitoring periods, gave rise to a total of eight exceedances of the European Commission (EC) PM 10 daily limit value as well as an increase in values of the crustal-derived elements (Fe, Mg, and Ca). Long-range transport from the heavily industria- lized area of Central/Eastern Europe contributed to the high levels of Zn, Cd, and Pb that were recorded during the winter sampling campaign. Seasonal trend and compar- ison with measurements previously performed across the Mediterranean basin were also presented and discussed