Quantification and speciation of lead in air particulate matter collected from an urban area in Amman, Jordan

Lead (Pb) is a carcinogenic element, and it originates in the atmosphere from various natural and anthropogenic sources. This work aims to provide further insights about the presence of lead in Amman's atmosphere. Air particulate matter (PM) samples were collected in two fractions (PM2.5 and PM10) simultaneously on Teflon filters in an urban area in Amman, Jordan. Elemental quantification and chemical speciation of Pb were performed using particle-induced X-ray emission (PIXE) and X-ray absorption near-edge structure (XANES) techniques, respectively. Elemental quantitative analysis using PIXE showed that Pb concentrations increased during workdays regardless of the aerosol particle size fraction. The average Pb concentration was 2.9 ± 1.7 ng/m3 and 3.9 ± 2.0 ng/m3 in PM2.5 and PM10, respectively. Based on XANES measurements, it was shown that both PM2.5 and PM10 in Amman contain divalent lead (Pb (II)), most likely as PbSO4, PbS and PbO compounds.