Radioactive contamination of aquatic ecosystems following the Chernobyl accident

The dynamics of radioactive contamination of aquatic ecosystems (1986–1990) is considered on the basis of observational data in the near and distant zones of the Chernobyl fallout (the Chernobyl Nuclear Power Plant (CNPP) cooling pond, the Pripyat River, the Dnieper reservoirs, and the Kopor inlet of the Gulf of Finland). Radionuclide accumulation in aquatic biota is analyzed. The results obtained indicate that the radioecological conditions in the water bodies under investigation were in a state of non-equilibrium over a long period of time following the Chernobyl accident. Reduction in the 137Cs concentration proceeded slowly in most of the aquatic ecosystems. The effect of trophic levels which consisted of increased accumulation of radiocaesium by predatory fish was observed in various parts of the contaminated area.