Fraction distribution and bioavailability of sediment heavy metals in the environment surrounding MSW landfill: a case study.

The aim of this study was to characterize the sediment samples from vicinity of a landfill in Qayen City, Iran. The samples were obtained from four different sampling stations. Sequential extraction was performed via a four-step procedure defined to evaluate the distribution of the element fraction in various samples. In the stations 3 and 4, Cd was found in large quantities during the first extraction F1, accounting for 40.4 and 38.7%, respectively. Pb was primarily presented in F2 of station 1 (approximately 44.80%), station 2 (approximately 41.8%), and station 4 (approximately 37.7%). Moreover, principal component analysis showed that heavy metal fraction in the sediment samples can be explained by two principal components (PCs). PC1 represented Cd, Cr, Ni, and Zn, while PC2 represented Pb and Cu. Pearson correlation coefficient indicated significant correlations in Cu-Pb, Zn-Cu, and Cr-Zn pairings. The present study concluded that the spatial distributions of sediment heavy metals were influenced by MSW landfill.