Background: Atmospheric deposition has a significant influence on environmental pollution and human health because of its role on transport mechanisms. The aims of this study were the determination of Concentrations, Sources and Ecological Risks of trace elements in atmospheric deposition of Karaj City, Iran.
Method: 18 atmospheric deposition samples were collected from the flat roof of buildings in six districts and then, the concentration of elements including Cu, Zn, Cr, Ni, Li and other (Co and Pb) were analyzed by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS), respectively. Pearson Correlation, One-Way ANOVA and Factor Analyses were used to identify probable sources of the trace elements.
Results: The mean concentrations of Pb, Zn, Cu, Cr, Ni, Co, and Li were 184.73, 931.75, 94.61, 98.79, 83.90, 21.05 and 24.71 μg/g, respectively. Also, the result showed the Enrichment Factors (EF) of Pb and Zn were high; Cr, Ni, and Cu were moderate while Co was unpolluted. Based on statistical analyses, trace elements could be originated from several anthropogenic (Vehicular Sources, Industrial Emissions and Fossil Fuel Combustion) and natural sources. Zn and Cu showed the highest concentrations at high-traffic stations, especially at Karkhene-Ghand located in city center. Maximum concentrations of Cr, Ni, and Co were observed at Fardis Station closed to Karaj Power Plant. Industrial Stations including Kamalshahr, Mohammadshahr, and Mahdasht had the most amount of Pb. Finally, Risk index (RI) showed all studied stations had low potential risk except of Kamalshar with a considerable risk.
Conclusion: Karaj has influenced by several anthropogenic sources of environmental pollution that are created many human health problems and the pollutants have increased with the population density. Therefore, we would have suggested the continuous monitoring of trace elements, especially Pb and Zn to control of the emission sources.