Abstract. An analysis of the chromium distribution among its individual fractions revealed that in municipal sewage sludge this metal was mostly bound to the solid phase (residue), and in industrial and municipal-and-industrial wastes – to organic matter. The chromium concentration in the fraction bound to iron and manganese oxides depended primarily on the origin of sludge, with the biggest amounts of chromium in this fraction being found in tannery sludge. Sequential chemical analysis of chromium combinations in sewage sludges showed that the total chromium content does not reflect the solubility of this metal or its availability to plants. Howewer, the levels found in this study may impair the quality of soil.

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