MUTAGENIC ACTIVITY OF TOTAL AND PARTICLE-SIZED FRACTIONS OF URBAN PARTICULATE MATTER

Total or inhalable (PM(10)) particulate matter is monitored as a quali ty air criteria. Airborne particles deposit onto the differently sensi tive biological tissues of the respiratory tract depending on their si ze. So it is very important to know the mutagenic activity (index of p otential carcinogenicity) of the substances carried onto the diverse s ized fractions of urban particulate matter, especially those under 1 m u m in diameter. The mutagenicity of total and sized fractions of urba n particulate matter of Bologna (Italy), representative of a medium si ze town surrounded by small and medium industries, was investigated us ing the plate incorporation test on Salmonella typhimurium. There is n o correlation between total and/or coarse particle matter concentratio n in air and mutagenic activity, the correlation increases as the part icle size decreases; moreover, the finer the particulate matter, the g reater the mutagenicity is. That is of great concern for health risk e stimation. Total or inhalable (PM(10)) particulate matter is not repre sentative of air quality, at least with regard to the mutagenicity.