Some improvements in air particulate matter analysis by INAA

At ITN, analysis of air particulate matter has been made since 1999/ stimulated by a contract for air quality monitoring of an urban waste incinerator. Samples are analysed by Instrumental Neutron Activation Analysis (INAA) and Proton Induced X-ray Emission (PIXE). Heavy metals and other elements are determined. The procedures for filter analysis have recently been changed, leading to the present comparison between the old and the new procedures. For INAA, in this new procedure we look for the 336.2 keV gamma line of 115mIn in addition to the gamma-ray line of 527.9 keV used for the detection of 115Cd. Cd evaluations obtained by both gamma lines are compared and detection limits for Cd are presented. Preliminary results for Cd, As, Ni, and Hg are shown for a region in the north of Lisbon.