The evaluation of Cr, Ni, Cu, and Co contents in bottom sediments of the Supraśl River and its tributaries

The aim of this study was to evaluate the total and soluble forms of Cr, Ni, Cu, and Co contents in bottom sediments of the Supraśl River and its tributaries. Studies were carried out in August 2005 and March 2006. The total contents of metals were determined, following the digestion of the sediments in nitric acid in a MARS 5 closed microwave system. Soluble forms of metals were extracted with 1 mol dm^-3 HC1 at the ambient temperature. The bottom sediments of the Supraśl and its tributaries are slightly contaminated with chromium. Copper, nickel, and cobalt occur mainly at a geochemical background level. A positive linear correlation between total forms of metal contents and their soluble forms was found.