Currently, the research of the migration of trace elements is of particular interest for hydrobiology, ecology and hydrochemistry. This growing interest is due both to deciphering biochemical processes, determining the role of trace elements in the functioning of living organisms, their importance in the functioning of ecosystems, and through the technical progress made in determining these elements. Particularly, the development of adsorption and atomic emission spectrometry greatly increased the knowledge of trace elements in the living environment and organisms. Thus, the need to determine trace elements is motivated by a large number of theoretical and practical problems. To understand the functioning processes of aquatic ecosystems, it is necessary to investigate the migration of trace elements in the multilateral systems "water-suspensions-bottoms sedimentshydrobionts", "water-phytoplankton-zooplankton-fish" and to decipher the ecotoxicological processes and the role of these elements in the life of aquatic organisms. The study of processes and level of accumulation of metals in fish, molluscs, both as aquatic organisms and food products, which can affect human health, is also of a high value. It is extremely important to study, together with the trace elements with toxic effects (Hg, Cd, Pb, As), the level, migration, accumulation processes, positive and negative effects of other elements, which role in the functioning of aquatic ecosystems is less known, such as are Bi, Se, Sr, Ba, Cr, Ni and others.