The mobilization and transfer of heavy metals to important sediment components after change of the physico-chemical conditions (redox potential, pH-value) in aquatic systems have been studied by using a multi-chamber device. Significant metal enrichments were found on algal cell walls, particularly for Cu and Cd, and on freshly precipitated iron hydroxide. Oxidation of anoxic mud from Hamburg harbour leads to lowering of pH and remobilization of Cd and Zn.