Fate of tannery chromium contamination in a stream: Temporal and spatial evolution of chromium (111) and chromium (VI)

Abstract

The cycle and transformations of Cr species originating from tannery wastewater were investigated in the upper Dunajec river catchment (South Poland). Contents of total Cr and Cr(VI) were measured in filtered water using catalytic adsorptive stripping voltammetry (CAdSV). Contents of Cr and Mn in bottom sediments and in suspended matter were determined with ICP-MS. With increasing distance from Cr sources, a decrease of Cr concentration and an increase of the Cr(VI)/Cr(III) concentration ratio in filtered water are observed. This may be attributed to coagulation/sedimentation of colloid-bound Cr(III) and possibly oxidation of Cr(III) to Cr(VI).