Migration forms of trace elements in natural fresh waters and the effect of the water storage

The concentration and physico-chemical state of 18 trace and major elements in river and lake waters were studied as a function of time (2h-35 days), for which the samples of water were stored in polyethylene bottles. The methods of investigation were dialysis, centrifugation, ion exchange filtration and electrophoresis, combined with instrumental neutron activation analysis. It was shown that considerable amounts of Mn, Co, Al, Sc, La, Ce, Fe, Cr and Th may be lost by the adsorption to the walls of polyethylene containers and that the ratio of forms of existence of Co, Mn, La, Ce, Sm, Fe, and Cr in the solution may be substantially changed during the storage for one week or more. Probable interpretations of these changes are given. Conclusions are also drawn about the state of individual trace and major elements in the waters studied.