Elemental composition of size-fractionated urban aerosol collected in Florence, Italy; preliminary results

An extensive investigation is in progress aiming at the characterisation of the air particulate composition in Florence, We present here the prelimina ry results concerning the analysis of size-fractionated aerosol samples tak en by two-stage streaker samplers in two sites characterised by different u rban settings (one in a heavy trams area, oils in a green area). The sampli ng period (21 January-22 February) includes two days during which the Munic ipality of Florence has banned the circulation of non-catalytic ears, due t o the increase of NO: above the "recommended safety values", Hourly concent rations of 20 elements from Na to Pb were determined using the external bea m PIXE facility of the I.N.F,N. Van dr Graaff accelerator at the Physics De partment of the Florence University. Factor analysis on the data set confir ms that traffic is the main source of atmospheric pollution in Florence, Th e ball of non-catalytic cars seems to have produced no effect on the concen tration of detected elements (in particular Pb and Br), (C) 1999 Elsevier S cience B,V. All rights reserved.