Zn, Cu, Pb, Cd, and Ni Levels in Tissues and Organs of the Main Representatives of the Lower Volga Ichthiofauna

Abstract

This article presents the results of studies of the content of heavy metals (zinc, copper, lead, cadmium, and nickel) in the muscles and liver of the main commercial fish of different levels of the trophic chain, e.g., pike, perch, roach, and bream, caught in the Astrakhan region, Chernoyarsk district in the water of the Volga River. The distribution of metals in the body of hydrobionts is uneven and depends on the properties of the metal itself and the functional characteristics of the organs. It was found that the content of these metals in the Volga water and the muscles of hydrobionts does not exceed the maximum permissible concentration. The goal of our work was to determine the content of heavy metals in the tissues (muscles) and organs (liver) of the most important commercial fish of the Volga basin within the Astrakhan region (Chernoyarsk region) and to assess the safety of their use as food raw materials. For the research, water samples were taken according to GOST 31861-2012. The content of heavy metals in water was determined via inversion voltammetry on a TA-2M analyzer and in the muscle tissue and liver via atomic absorption spectrometry on a Quant-2A instrument. The highest concentration of heavy metals, 0.14–39.6 mg/kg, is found in the internal organs (liver), and the lowest concentration, 0.038–8.13 mg/kg, is found per unit mass of muscle tissue.