Assessment of trace element concentrations and their estimated dry deposition fluxes in an urban atmosphere

Thirty-three ambient air samples were collected during spring and summer (2003) in the metropolitan area of Bursa, Turkey. All airborne samples were analyzed for crustal (Mg, Ca, Mn, Fe) and anthropogenic (Cr, Co, Ni, Cu, Zn, Cd, Pb) trace metals. A TSP sampler was employed using glass and quartz fiber filters to collect air samples. Average individual trace element concentrations fluctuated between 4896.3 ± 3754.3 ng/m3 (Ca) and 0.7 ± 0.9 ng/m3 (Cd). The measured concentrations of the trace elements were within the ranges of previously reported values obtained from different places including Turkey, Argentina, Spain, Korea, and Brasil. The concentrations were arranged according to day and night, weekend and weekdays, spring and summer samples. Concentrations were also evaluated based on the filter types used, glass fiber and quartz filters. Enrichment factors (EFs) were calculated to identify anthropogenic versus natural emission sources of trace elements. The prevailing winds from various sectors were examined to determine the transport of metal particles from different districts. Principal component analysis (PCA) was employed to define the possible origins of trace elements in airborne particulate matter. The result suggested that industrial activities along with traffic emissions and suspension of street dusts have important effects on ambient air concentrations of trace metals. Dry deposition fluxes were estimated using documented dry deposition velocities in the literature and concentrations measured in this study.