ABSTRACT
Nearly 10-year (2013-2022) data on atmospheric particulate matters (PMs) were collected to investigate the air quality in a suburban site of Orléans city (France). The PM10 concentration decreased slightly between 2013 and 2022. PMs concentrations showed a monthly variation with higher concentration in cold periods. PM10 presented a clear bimodal diurnal variation peaking at morning rush hour and midnight, whereas the fine PMs such as PM2.5 and PM1.0 only had significant peaks during nighttime. Further, PM10 had more pronounced week-end effect than other fine PMs. COVID-19 lockdown impact on PMs levels was further investigated, showing that the lockdown during cold season could result in an increase of PMs concentrations because of the enhanced household heating. We concluded that PM10 could originate from biomass burning and fossil fuel related activities, air parcels from the western Europe through Paris were also important source of PM10 in the investigated area. Fine PMs, such as PM2.5 and PM1.0, originated mainly from biomass burning in addition to secondary formation at the local scale. This study provides a long-term PMs measurement database to explore the sources and characterization of PMs in central France, which could support future regulation and formulation of air quality standards.