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Montale is a small town in Tuscany characterised by high PM10 levels. Close to the town there is a waste incinerator plant. There are many concerns in the population and in the press about the causes of the high levels of pollution in this area. Daily PM10 samples were collected for 1 year by the FAI Hydra Dual sampler and analysed by different techniques in order to obtain a complete chemical speciation (elements by PIXE and ICP-MS, ions by Ion Chromatography, elemental and organic carbon by a thermo-optical instrument); hourly fine ( Positive Matrix Factorization identified and quantified the major aerosol sources. Biomass burning turned out to be the most important source with an average percentage contribution to PM10 of 27% of and even higher percentages during the winter period when there are the highest PM10 concentrations. The contribution of the incinerator source has been estimated as about 6% of PM10.

The chemical characterization of size-segregated samples is helpful to study the aerosol effects on both human health and environment. The sampling with multi-stage cascade impactors (e.g., Small Deposit area Impactor, SDI) produces inhomogeneous samples, with a multi-spot geometry and a non-negligible particle stratification. At LABEC (Laboratory of nuclear techniques for the Environment and the Cultural Heritage), an external beam line is fully dedicated to PIXE–PIGE analysis of aerosol samples. PIGE is routinely used as a sidekick of PIXE to correct the underestimation of PIXE in quantifying the concentration of the lightest detectable elements, like Na or Al, due to X-ray absorption inside the individual aerosol particles. In this work PIGE has been used to study proper attenuation correction factors for SDI samples: relevant attenuation effects have been observed also for stages collecting smaller particles, and consequent implications on the retrieved aerosol modal structure have been evidenced.

PIXE and ICP-AES techniques are largely used in atmospheric aerosol studies. Since PIXE is able to provide the total elemental concentrations, while ICP-AES results depend on the extraction conditions, parallel PIXE and ICP-AES measurements of Fe, Al, Cu, Pb, Mn, Cr, Ni, V, As on PM10 and PM2.5 samples were compared. Two extraction procedures were applied to samples from 5 sites at different anthropization level in Italy: a “weak” extraction (HNO 3 at pH = 1.5) and a “strong” extraction (micro-wave oven in HNO 3 and H 2 O 2 – following EU rules). The amount of the metal extracted in the different conditions resulted to be strongly dependent on the sampling site, on the main sources of the particle (crustal or anthropic) containing the metal and on the sampled size class.