Background: Entrance of heavy metals into the respiratory system has adverse effects on human health. Accordingly, measuring metals concentration in places and times is necessary. Objectives: This study was done to evaluate the non-carcinogenic risk of Pb, Cd, and As in air suspended particles of Baharestan city, in Isfahan, during 2016 -2017. Methods: In order to evaluate the non-carcinogenic risk of heavy metals in air suspended particles (PM10), sampling was performed using a SKC pump with a low volume (1.5 L/min) and 37 mm membrane filter. Sampling was carried out on average every three days during 24-hours finally, the concentration of Pb, Cd, and As was determined using atomic absorption spectrometry (AAS) and hydride generation atomic absorption spectrometry (HGAAS), respectively. The acute and chronic non-carcinogenic risk of heavy metals sorption in the air was evaluated using the EPA method. Results: The highest and lowest Pb concentration belonged to May -June and October -November, with the mean concentration of 0.25 and 0.14 mg/kg, respectively. For Cd it was 0.017 and 0.009 mg/kg, respectively. Similar results were found for the air suspended particles. The highest and lowest Cd non-carcinogenic risk was observed for permanent residents of Baharestan city and the nondormitory students of this city with the mean of 3.1 × 10 -5 and 1.4 × 10 -5 , respectively.
Conclusions:The results of this study showed that the non-carcinogenic risk of heavy metals was lower than the standard level during the study years. However, heavy metal accumulation can threaten human health, which needs more consideration.