Size distribution of organic pollutants and biological activity in ambient particulate matter and biological activity in ambient particulate matter

The aim of this research was (1) to investigate the distribution of organic compounds associated with size segregated atmospheric aerosols, (2) to determine the redox activity and the mutagenicity of size-fractionated particulate matter (PM) and (3) to assess the role of organic species in generating these biological activities. More precisely, the concentrations of 18 PAHs, 2 NPAHs, 19 OCPs, 6 PCBs, 10 AHs and 2 isoprenoids compounds were determined in different size fractions. Seasonal variations of concentration levels, particle size distribution were also examined, so as to estimate their ambient environmental sources and to provide helpful information about the environmental levels of these harmful substances. Furthermore, the biological effects of size-separated PM were determined by measuring the mutagenicity using S.Typhimurium strains TA98 and TA100, with and without metabolic activation and the redox activity. Data form the biological tests were correlated with chemical data in order to elucidate the mutagenicity and the redox activity of size fractions as a result of the presence of the targeted compounds or not. Sample acquisition was carried out at an urban site of Thessaloniki, adjacent to a busy street, during winter (11-27 December 2007) and summer (3-27 June 2008). Particles were separated into five fractions (4 stages and a back up filter) resulting in size ranges of >7,5, 7,5-3,0, 3,0-1,5, 1,5-0,95, 7,5 μm were significantly higher in summer period