PM10 source apportionment at two urban sites in Southern Poland

The main aim of the study was to achieve a better understanding of the chemical composition, seasonal variation, and sources of ambient particulate matter in two mid-sized towns in Southern Poland, characterized by a significant air pollution issues: Nowy Targ and Zabierzów. Daily PM10 samples were chemically analyzed for the content of water-soluble ions, carbonaceous matter and trace elements. Positive Matrix Factorization (PMF) was applied for source apportionment. The annual mean PM10 concentrations were 38 μg/m3 and 41 μg/m3 in Zabierzów and Nowy Targ, respectively. Secondary species (SIA + SOC) constituted, on average, 23% of PM10 in Nowy Targ, while in Zabierzów, this share varied from 32% to 41% during the non-heating and heating seasons, respectively. The proportion of primary pollutants (EC + POC) in PM10 substantially increased during the heating season in both locations, reaching 24% and 37% of PM10 in Zabierzów and Nowy Targ, respectively. PMF analyses identifies four sources with similar profiles at both sites: residential coal combustion, residential wood combustion, road transport, and secondary aerosol. In both locations, residential coal and wood combustion were the largest contributing sources (on average 44% and 50% of PM10 in Zabierzów and Nowy Targ, respectively), followed by road transport (on average 14% and 21% of PM10). Local sources were the dominant contributors to PM10 at both sites, accounting for 86% and 90% of PM10 in Nowy Targ and Zabierzów, respectively. These findings underscore the importance of implementing control strategies tailored to local factors to improve air quality in these towns