Abstract The presence of airborne potentially toxic elements (PTEs) in the atmosphere of densely populated cities and industrial areas has been proven in various studies. The presence of these elements is a great threat to these areas. This study focused on the city of Tehran, a densely populated and heavily trafficked metropolis of Iran. The deposition of some potentially toxic elements, namely Cr, Fe, Pb and Zn, has been investigated in the southern part of Tehran with the technique of the lichen transplant, using the species Anaptychia setifera. Thalli of A. setifera were collected from a remote area in Savadkuh area (control site) far from any local source of pollution, and transplanted for four months in Shahr-e Rey, Region 16, Shadabad and Region 19. The content of the 4 elements investigated was determined by ICP-MS. The results showed a great accumulation (>100%) for all elements at all monitoring sites. The highest values for Cr, Fe and Pb were observed in Shahr-e Rey, while the highest values for Zn were observed in Shadabad. It is concluded that biological monitoring with transplants of the lichen A. setifera can be used as an effective method to check air quality also in other similar areas.
