This thesis analyses the chemical composition and variability of PM10 in the Po Valley, within the framework of the LIFE PrepAIR project; The study aims to investigate the PM10 trends, its seasonality and to characterize its chemical composition, exploring the influence of emission sources and meteorological drivers, verifying the compliances with the current and future targets and limits defined by the European directives and World Health Organization guidelines. The analysis examined daily samples collected between 2018 and 2019 at five urban and rural background stations, regarding inorganic ions, trace elements, organic and elemental carbon (OC/EC), and levoglucosan. The results showed that the main components in all the sites were secondary inorganic species and organic carbon, with pronounced seasonal variability, associated with winter atmospheric stagnation and seasonal differences in emission patterns.