Environmental availability of trace metals (Mercury, chromium and nickel) in soils from the abandoned mine area of merník (Eastern Slovakia)

Abstract

The former mercury ore deposit of Merník in Eastern Slovakia was selected for the investigation of the environmental availability of mercury (Hg), chromium (Cr) and nickel (Ni) in mine soils. Single-step extractions with four chemical agents (deionised water, ethylenediaminetetraacetic (EDTA), acetic (CH3 COOH) and hydrochloric (HCl) acid solutions) and chemical analysis of the common nettle (Urtica dioica) were used to determine the availability of the three metals. Regardless of the type of extraction, the soluble ratios of metals in mine soils increased in the order of Hg≤Cr CH3 COOH ≈ EDTA>˃H2 O. The total or extractable metal concentrations in soil did not correlate with their concentrations in aerial parts of the common nettle, however, its ability to accumulate these trace metals in roots and aerial parts copied the results of extraction tests, i.e. Hg≤Cr