The article highlights the methodical features of hygienic regulation of pesticide preparation in water bodies, concretizes and supplements (specified) number of positions of the acting current methodical document on hygienic evaluation of new pesticides. From the position of the comprehensive hygienic standardization there are marked principles of the study of MPC for pesticides in water bodies, there is substantiated the expediency of expanding the arsenal of methods for determination of threshold concentrations of pesticides on the impact on organoleptic properties of water and sanitary regime of reservoirs, shows the role and importance of hydrolysis processes of active ingredients ofpesticides in water, which should be considered in the assessment of the impact of drugs on the processes of self-purification of water bodies.

The global pollution of the environment and the functioning of the Mining and Chemical Combine (MCC), Rosatom State Corporation are potential sources of tritium in the Yenisei River ecosystem. The distribution of residual tritium in organs and tissues of the freshwater rayfinned fish Carassius gibelio (Prussian carp) as a representative of the Carassius phytophagous genus of Cyprinidae family was studied for the determination of the 3Н accumulation in the aquatic plants-fishes food chain in water bodies contaminated with radionuclides. At the first stage, the work was done on the accumulation of tritium by the biomass of hydrobiont plants. To do this, 3000 g of biomass in terms of wet weight were placed in aquaria with a volume of 100 liters with specific water activity of 100 kBq/l. The work shows mentioned aquatic plants to accumulate actively the introduced tritium, storing up to 70% of the radionuclide. At the same time, the content of organically bound tritium in biomass increased to 21% of total accumulated tritium. Then the plants (hornwort, duckweed) were dried, mixed with dry fish food (1: 1), and the mixture was compressed into pellets, each with activity up to 50 Bq. The pellets were used for forcible feeding of fish, during the experiment, each individual absorbed up to 330 kBq of tritium radionuclide for 550 days. Studies have shown about 75% of the total accumulated amount of tritium in fish specimens to present in muscle tissue. When determining the content of tritium in proteins and lipids in experimental systems, no specific features have been revealed in the use of Ceratophyllum and Lemna as a source of nutrition.