Air-intake filters used for multi-element analysis of airborne particulate matter by inductively coupled plasma atomic emission spectrometry

Abstract

Airborne particulate matter was collected from air-intake filters from various buildings and analysed by sequential inductively coupled argon plasma atomic emission spectrometry. The filters studied were glass and polyester fibre mats and bags and the following metals were determined: Al, Cr, Mn, Fe, Ni, Cu, Zn, and Pb. The particulate matter was decomposed by two procedures: an open system uisng a mixture of nitric and perchloric acids, and a pressurized system using nitric and hydrofluoric acids. The analytical procedures were checked by analysing a standard reference material, NIST SRM 1648 Urban Particulate Matter. For most of the samples, the concentration of the elements was found to decrease in the order Fe > Al > Zn > Pb > Cu ≈ Mn > Cr > Ni > Cd. To assess the potential bioavailability of the metals, two leaching schemes were used. The first utilized water and nitric acid and the other used sequential leaching with five solutions. Based on solubility in sodium acetate solution, the results indicate that the mobility of the metals decreases in the order Cd > Zn > Pb > Mn ≈ Ni > Cu > Cr > Fe ≈ Al. The study shows that air-intake filters used in ventilation systems may be utilized as sampling devices for the elemental analysis of airborne particulate matter.