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The results on elemental composition of aerosol (PM 10 ) sampled during 2011 in Piedmont region (Italy) are interpreted using meteorological data, Enrichment Factors (EF), chemometric processing by Principal Component Analysis (PCA), Factor Analysis (FA) and Hierarchical Cluster Analysis (HCA). Daily concentrations of about 30 elements were measured using HR-ICP-MS in five monitoring sites. A clear seasonal pattern, with higher concentrations in autumn and winter, was observed, particularly in the urban sites. Levels of As, Cd, Ni and Pb in most of the samples were within the limits imposed by the European legislation. Spatial differences in PM 10 and metal concentrations were significant, with rural and urban sites showing different metal patterns, indicating different sources. K and Ca were used, respectively, as marker of biomass burning and industrial marker (cement plant); EFs showed that Ca was enriched just in one area and K was enriched only in the winter period considered and in some stations. Data analysis through PCA, FA and HCA allowed us to identify correlations among the investigated elements and similarities between sampling sites in order to individuate specific emission sources, such as non-exhaust vehicle emission. [ABSTRACT FROM AUTHOR]

Abstract: The temporal trends of major, minor and trace elements in the total atmospheric particulate sampled in the urban area of Turin (Italy) were determined for the following years: 1976, 1986, 1996 and 2001. The wavelength dispersive X-ray fluorescence (WD-XRF) technique was adopted to determine the concentrations of Ba, Br, Ca, Cl, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, S, Ti and Zn. A smaller number of samples was also analysed by ICP atomic emission spectroscopy (ICP-AES) and the results were compared with those obtained by WD-XRF to confirm their validity. A clear seasonal pattern with higher concentrations of the aforementioned elements in the cold periods was observed. Moreover, a change in the chemical composition of atmospheric particulate matter was evidenced, particularly between the first (1976 and 1986) and the last (1996 and 2001) years. This change can be attributed both to the greater contribution of Pb and Br to atmospheric pollution in the past and, in recent years, to the higher level of pollutants associated with increased vehicular traffic and industrial activities. The application of chemometric techniques (Principal Component Analysis and Cluster Analysis) allowed us to speculate about the main emitting sources influencing the total atmospheric particulate in these years. [Copyright &y& Elsevier]

Abstract: The temporal trends of ten elements, namely Cl, Cu, Cr, Fe, Mg, Ni, P, S, Zn and Zr, in airborne particulate matter sampled in the urban area of Turin (Piedmont, Italy) were determined by wavelength dispersive X-ray fluorescence for the period from 2002 to 2005. The average daily concentrations were as follows: Cl 322ng/m3; Cr 16.4ng/m3; Cu 8.19ng/m3; Fe 274ng/m3; Mg 1501ng/m3; Ni 7.33ng/m3; P 19.8ng/m3; S 1206ng/m3; Zn 333ng/m3 and Zr 8.15ng/m3. Some elements, namely Al, Ba, Ca, K, Na, Si and Sr, were not quantifiable using XRF because of the too high contribution from the filter blank. A clear seasonal pattern with higher concentrations of most of the elements in the cold periods was observed. Moreover, no marked change in the element distribution in atmospheric particulate matter over 4years was evidenced during the sampling period, to indicate that similar sources have influenced the elemental composition of it in these last years. The application of multivariate chemometric techniques (principal component analysis and hierarchical cluster analysis) to the experimental results allowed us to identify correlations among the investigated elements and to reveal similarities and differences between sampling sites. [Copyright &y& Elsevier]