RISK ASSESSMENT FROM CONTAMINATION OF AQUATIC ECOSYSTEMS IN THE AREASOF CHERNOBYL AND URAL RADIOACTIVE PATTERNS

A comparative analysis of the generalised data on radioactive contamin ation of aquatic ecosystems in the areas of Chernobyl and Ural radioac tive patterns has been performed. The estimated contents of Sr-90 and Cs-137 in water, bottom sediments and fish are presented for river, la ke and sea water bodies. The most highly contaminated water bodies hav e been revealed, namely, Chernobyl NPP cooling pond, the Techa River a nd several lakes in Chelyabinsk and Bryansk Regions. The results of an alysis of risks imposed by radioactive contamination of the aquatic ec osystems are given. It has been shown that the levels of radiation ris k from the water use in the Techa River basin and lakes in Bryansk Reg ion can be comparable to or slightly in excess of the radiation backgr ound risk.