[The dynamics of 137Cs and 40K accumulation in the tissue of food species of fish in the Tobol and Irtysh Rivers during 1995-2007].

The results of long-term investigations of 137Cs and 40K accumulation in the tissue of food species of fish in the Tobol and Rivers were analyzed. It was revealed, that the highest specific activity of 137Cs is characteristic for predatory species of fish. Yearly, seasonal and age peculiarities of 137Cs accumulation in fish were examined in this work.

[The peculiarities of accumulation of 137Cs in fish of the highest trophic level from the reservoirs polluted by radioactive nuclides as a result of the ChNPP].

In this paper, we analyze the results of long-term investigations of 137Cs accumulation in the specimens of fish of the highest trophic level, pike and pike perch, from the reservoirs suffered as a result of the ChNPP. Annual, seasonal and age peculiarities of accumulation of the 137Cs specific activity in the predatory fish from the Kiev reservoir and Teterev River were considered. It was shown, that during the whole time of radioecological investigations the pike was characterized by the higher level of 137Cs specific activity muscles in comparison with other predatory fish, in particular, pike perch.

[Use of microwave ovens in the prevention of opisthorchiasis].

The studies were performed to evaluate the impact of microwave radiation on the larval stages of parasites and particularly on the survival of Opisthorchis metacercariae when fish was cooked in domestic microwave ovens. It was found to take less time to free fish and its products from Opisthorchis metacercariae in the microwave oven than that to cook the product completely. The performed experiments have shown that the use of microwave ovens to domestically prepare carps from unfavorable opisthorchiasis water reservoirs is an effective mean of freeing fishes from Opisthorchis metacercariae.

[Model for calculation of fish contamination by 137Cs and its application for Lake Kozhanovskoe (Bryansk Region)].

A dynamic model was developed for evaluation of the fish contamination by 137Cs. The dynamics of the accumulation of the radionuclide and the elimination is calculated taking into account the ecological and physiological characteristics of the fish, such as growth and metabolic rates, its position in the food chains of the aquatic ecosystem. The biological elimination of 137Cs from the freshwater fish is proportional to the metabolic rate of the fish.

[Modeling of different types of size-effect in accumulation of 137Cs in fish from the cooling pond of the Chernobyl Power Plant].

All known types of size-effect in accumulation of radiocesium in fish are described on the basis of the dynamic model of distribution and migration of the radionuclide in aquatic ecosystem. The time-dependent activity of 137Cs in different age classes of carp and pike-perch from the Chernobyl Nuclear Power Plant Cooling Pond is calculated. It is shown that during the first year after the accident the activity of 137Cs in the young generations of fish was higher (negative size-effect) owing to higher feeding rate of young fish.