Elemental concentration and source identification of PM10 and PM2.5 by SR-XRF in Córdoba City, Argentina

Abstract

24-h samplings of PM10 and PM2.5 have been carried out during the period July 2009-April 2010 at an urban and at a semi-urban site of Córdoba City (Argentina). The samples in the PM2.5 fraction weighted in the average 71 ± 21 μg m-3 and 67 ± 18 μg m-3 respectively, whereas the samples of the same sites in the PM10 fraction weighted 107 ± 31 μg m-3 and 101 ± 14 μg m-3. The chemical composition of aerosol particles was determined by synchrotron radiation X-ray fluorescence (SR-XRF). Elemental composition was different in the two fractions: in the finer one the presence of elements with crustal origin is reduced, while the anthropogenic elements, with a relevant environmental and health impact, appear to be increased. An important but unmeasured component is likely constituted by organic and elemental carbon compounds. Multivariate analysis (Positive Matrix Factorization) of the SR-XRF data resolved a number of components (factors) which, on the basis of their chemical compositions, were assigned physical meanings. © 2011 Elsevier Ltd.