Influence of Filters, Solid to Fluid Ratios and Matrices on the Bioaccessibility of Potentially Toxic Elements in Airborne PM

Abstract

Determination of bioaccessibility of potentially toxic elements in inhaled airborne particulate matter has brought the attention of researchers. In this study, the effect of filters and solid-to-fluid ratios on the bioaccessible fraction of elements in airborne particulate matter determined by the simplified bioaccessibility extraction test was investigated. A matrix-matched and a non-matrix-matched set of calibration standards for inductively coupled plasma mass spectrometry was also examined. Nine elements: As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined. Results obtained illustrated that matrix matching was necessary for preparing As calibration standards. Results also indicated that the ratio adopted in the miniaturized version of the simplified bioaccessibility extraction test (0.1 g:10 mL) is the best choice when all elements tested are to be measured, compared to other ratios investigated in this study. However, all ratios can be applied with no significant difference for Cd, Cu and Ni. Results from filters' effect demonstrated that the relative percent difference between the bioaccessible fraction of elements in soil only and in soil loaded on filters was less than 20% for all elements except for Cd, Ni and Zn. Discrepancies observed for Zn were due to the variability in its amount used to produce filters.