When citing, please refer to the published version.Link to this full text: http://hdl.handle.net/2318/150871 32PM induced TA98 > PM induced TA98+S9 >> non-particle induced YG1021 > non-particle induced TA98 > 33 non-particle induced TA98+S9. The multivariate regression is significant when we consider air pollution and 34 meteorological indicators and chemical conditions as predictors. 36 HIGHLIGHTS 37Both chemicals and meteo-chemical parameters can influence the mutagenicity of air pollution. 38The gas phase and particulate phase mutagenicity can be different and affected by season. 39The gas phase accounted for only 1% of the observed mutagenicity. 40The particulate mutagenicity is approximately 5-fold higher during winter. 41The contribution of the nitro-derived compounds seems to be crucial. 43 Introduction 44Air pollution is one of the most important worldwide health concerns (WHO-Europe, 2013 48European citizens are deeply concerned about the impact of air pollution and that more than 70% of the 49European population is worried that air pollution and air quality is worsening over time (EU, 2013 69(1 Group) (Loomis et al., 2013). 70Many mutagenic and genotoxic compounds are present in air pollution, and the effects are widely known 71 and reviewed (de Kok et al., 2006; Claxton and Woodall, 2007a;Valavanidis et al., 2008; DeMarini, 2013). 72The finest air pollution fractions, PM10 (particles with a diameter of less than 10 µm) and PM2. 90Vapor-particle partitioning of mutagens can be quantified using the gas-particle-partitioning coefficient for 91 each compound. This coefficient is influenced by both the adsorption and absorption processes and is 96The aim of this work is to assess the mutagenicity of particulate and not-particulate air pollution and to ; thus, the pressure on the territory that is associated with human 108 activity is very high (ISTAT, 2012 115The TSP were collected on glass fibre filters, and the polyurethane foam (PUF) cartridge was placed in series 116 after the glass fibre filter. The volatile compounds, which were not trapped on the filter, were retained in 117 the PUF cartridge. 118The sampling flow was electronically controlled to be 250 L/min. Each sampling duration was controlled by 119 a timer that was accurate to ± 15 min over a 48-hour sampling period. The exact flow rate was calculated 120 daily and corrected for variations in atmospheric pressure and actual differential pressure across the filter. 121The filters were conditioned for 48 h and were weighed using an analytical balance (± 10 µg) before and 168 Gravimetric analysis 169The descriptive analysis of the collected data is shown in 192The higher mutagenicity of the winter particles was confirmed also adjusting the data for particles mass 193 unit (Figure 3), highlighting the worse quality of the particles-in terms of mutagen presence -and not only 194 the higher level of aero-dispersed pollution for each volume unit. 195Among the chemicals variability we observed a not so great changeability during the year for P...