MUTAGENS AND CARCINOGENS IN SIZE-CLASSIFIED AIR PARTICULATES OF A NORTHERN ITALIAN TOWN

This research was designed to examine the presence of mutagenic/carcin ogenic compounds in urban airborne particulate matter in relation to p articles aerodynamic size. Inhalable (<10 mu m) airborne particulate ( PM-10) was collected at a low traffic site in an industrialized Northe rn Italian town, using a high volume sampler equipped with a cascade i mpactor for particles fractionation. The organic extracts of different fractions were examined for mutagenicity in Salmonella typhimurium st rains TA98 and TA98/1,8-DNP6 using the microsuspension procedure, and for polycyclic aromatic hydrocarbons (PAHs) content by gas chromatogra phy. Size fractionated particles were also analysed for heavy metals ( Fe, Mn, Zn, Pb, Cu, Cd, Cr, Ni, V) using plasma spectrophotometry. The results of mutagenicity and chemical analyses indicate that, at the s ite investigated, inhalable particulate was largely made of fine (< 0. 5 mu m) particles, which accounted for most of PAHs and mutagenicity. A similar pattern of distribution was found for heavy metals, which we re relatively more abundant in small (< 1.5 mu m) particles compared t o coarser ones. (C) 1997 Elsevier Science B.V.