In recent years, heightened air pollution characterized by elevated levels of particulate matter and potentially toxic metals has become a prominent concern, particularly in densely populated urban areas, which may pose a threat to the health of the population. The present study aims to conduct a comprehensive health risk assessment of heavy metals exposure via inhalation, with a focus on submicron particles (PM1), in two major cities of Poland - Warsaw and Zabrze. These cities were selected due to their distinct levels of urbanization and industrialization. Non-carcinogenic and carcinogenic risks assessment was performed for children and adults. The carcinogenic risk was evaluated for As, Cd, Cr (VI), Ni, Pb, and Co, classified as carcinogens, the non-carcinogenic risk evaluation encompassed a broader range of metals, including V, Mn, Cu, Zn, and Mg, aiming to comprehensively understand health exposure. The results highlight elevated carcinogenic risk in Zabrze, primarily linked to industrial activities and ongoing emissions. Notably, Ni, As, and Cr(VI) exceed safe limits, underscoring the need for targeted interventions. Moreover, non-carcinogenic risks reveal Zabrze's heightened respiratory health risks, compared to Warsaw. Despite Warsaw's lower non-carcinogenic risk values, both cities recorded Ni and Mg concentrations exceeding safe limits. This indicates that Zabrze faces higher health risks from heavy metal exposure due to ongoing pollution sources. In contrast, Warsaw, the capital city and a major urban centre, demonstrates better air quality but still requires continuous monitoring and pollution control measures.