In the present study, BCR 3-step sequential extraction procedure was applied to determine the fractionation of heavy metals in TSP samples collected from urban locations in Changsha, China. The average TSP concentration at Changsha in May was 220.7 µg m-3 showing that the particle pollution is serious in Changsha. The distributions of heavy metals (Cu, Zn, Mn, Pb, Cd) in different spots were evaluated and the order of average concentrations of heavy metals in Changsha atmospheric air was Zn > Pb > Cu > Mn > Cd. From the percentage distribution of species, approximately 63.3%~89.0%of total Cu present in oxidizable fraction (F3), whereas Mn has the lowest concentration in oxidizable fraction almost below the detecting limits. While Zn and Cd mainly appear in the exchangeable and weak acid soluble fraction (70% and 35%, respectively), Pb prevails in residual fraction (24~43 %). Contamination factors showed Cu, Cd and Zn had higher values indicating a high mobility and Mn and Pb having comparatively low Cf values. Principal component analysis (PCA) was applied to evaluate the analytical results and to identify the possible pollution sources of metals in Changsha.
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