Chemical speciation and bioavailability of transuranics for a freshwater snail (Lymnaea stagnalis L.)

It is now becoming clear that the determination of the physico-chemical forms of transuranic elements is an important step in assessing their behaviour at very low environmental levels. Data from both simulated environmental systems as well as in-situ investigations have shown the necessity of understanding the source term of contamination, which probably plays a major role in the long-term distribution of these elements. In the present paper an experimental procedure is outlined, which allows a more extensive investigation into some aspects of the biogeochemical behaviour of two transuranics: 237Pu and 241Am. Two chemical methods were applied to a study of the freshwater snail Lymnaea stagnalis L.. Data were obtained on the uptake and retention patterns of different oxidation states of 237Pu and 241Am at the organ and cellular levels of the pond snail. An attempt was made to relate the environmental chemistry of both radionuclides to the fixation in L. stagnalis. (author)