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Heavy Metal Accumulation in Street Dust Samples in Sivas

Heavy metal contents of street dust samples collected from seven sites located in and around urban areas in Sivas city, Turkey, were determined by atomic absorption spectrometry after digestion using a mixture of acids. The results of the analyses were used to determine major sources and magnitude of heavy metal pollution, and were compared with the background values. The mean concentration levels of lead (Pb), zinc (Zn), nickel (Ni), copper (Cu), and cadmium (Cd) were found to be 197, 206, 68, 84, and 2.6 μg g−1, respectively. High concentrations of heavy metals were detected in street dust samples collected in close proximity to emission sources such as motor-vehicle emissions and industrial area. The heavy metal levels in urban street dust samples were several times higher than the background levels. After heavy metal pollution factors of each site were determined, their possible pollutant sources were determined. The levels of the metal ions were compared with the mean worldwide contents of the street dust samples. The precision of method varied between 2.0 and 6.8% (n=42) as average relative standard deviation (RSD %) depended on the analyte and nature of the sample.