Labile and bioaccessible fractions of heavy metals in the airborne particulate matter from urban and industrial areas

Total, labile and bioaccessible concentrations of heavy metals (Cd, Cu, Mn, Ni, Pb and Zn) were determined in the airborne particulate matter (d<7.2 μm) from various urban and industrial sites in the Greater Thessaloniki area, N. Greece. Particle mass concentrations were similar at the two site types; however, total Mn, Ni, Zn and Cd exhibited higher concentrations in the industrial area. Urban particles were found to contain higher labile fractions of Cd, Cu, Ni and Zn than industrial particles suggesting that they are emitted from different sources and in different, more soluble, chemical forms. The bioaccessible fractions of Mn, Ni and Zn were also higher at the urban area, therefore, posing a potentially higher health risk. The daily respiratory uptakes of heavy metals were calculated.