Heavy metal contamination of topsoil and parts of peach-tree growing at different distances from a smelting complex

Abstract

This paper reports on the content of six heavy metals (Cu, Zn, Pb, As, Cd and Ni) in topsoil and parts of peach-tree, sampled from eight locations in urban–industrial and rural areas located at various distances from the Bor copper smelter, Serbia. Topsoil samples were analyzed for physical and chemical properties, while the content of heavy metals in all samples was determined using an inductively coupled plasma optical emission spectrometer (iCAP 6000). The enrichment factor showed that the topsoil was enriched by heavy metals (except for nickel), at all locations. An extreme enrichment by copper was found at six locations (EFsoil = 86–101). The enrichment factors of heavy metals in peach-tree parts were highest in roots and leaves. The most extreme enrichment by copper was found to occur in the roots (EFplant = 68.80) from the flotation tailing pond. Among the studied heavy metals, only the content of zinc was within normal limits for plants. Calculated biological concentration factors (BCF < 1) indicated a limited soil-to-root transfer of heavy metals. Moreover, the leaf/branch ratio as well as numerous and very strong Pearson’s correlations between elements in the peach-tree parts confirmed that leaves represent the best indicators of pollution originating from atmospheric deposition. Principal component analysis identified sources of heavy metals in soil and parts of peach-tree.