This paper presents the results of the air quality measurements conducted at the Jugopetrol (JP), Brezonik (BR), Krivelj (KR), and Oštrelj (OS) sites, as a part of the air quality monitoring program within the territory of Bor, covering the period from August 2023 to July 2024. At the JP, BR, and OS monitoring sites, the number of days exceeding the daily limit value surpassed 35 days. At the JP site, exceedances of the daily limit value for lead concentration in PM10 were recorded on eight occasions. Additionally, at the JP site, the average concentrations of cadmium and arsenic in PM10 exceeded the annual target values. Similarly, at the BR site, the average concentration of arsenic in PM10 was found to be higher than the annual target value. During the trial operation period of the copper smelter, the JP site recorded 33 days where arsenic concentrations in PM10 were more than 20 times higher than the target annual value (6 ng/m³). Furthermore, at the same site, cadmium concentrations in PM10 exceeded the target annual value (5 ng/m³) by more than 20 times on three days. These findings suggest that, despite the recent reconstruction efforts, the issue of elevated emissions of carcinogenic elements in PM10 from the Copper Smelter persists. Therefore, the urgent implementation of additional measures is necessary to reduce these emissions to comply with legally prescribed limits.