Particle size distribution of metals in the atmosphere of Glasgow

Abstract

The size distribution of nine metals (Al, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) present in Glasgow's atmosphere expressed in terms of the mass-median diameter is, with two exceptions (Al and Cd), in good agreement with values reported from elsewhere. The most toxic metals studied (Cd, Ni and Pb) have extremely high proportions in the smallest particle size range which can easily enter the respiratory tract and lodge in the alveoli. The other metals have 29–83% in the same size range (less than 0.7 μm). The remaining fractions of the metals can easily pass the nasal passage and enter the upper sections of the lungs where adsorbed species can act more focally. When enrichment factors based on soil proportions are calculated for the metals on each stage the pattern obtained for whole sample analysis is repeated, i.e. the enrichment factors for Al, Cr, Fe and Mn are close to unity while the enrichment factors for Cd, Cu, Ni, Pb and Zn are higher and tend to vary from stage to stage indicating additional pollution sources.