The ingress of oil, petroleum products and wastewater, as well as toxicants by aerogenic means, discharges of industrial enterprises – this is an incomplete list of ways for pollutants to enter the hydrosphere. As a result, chains of complex transformational, in some cases reversible, processes are launched, which have a significant impact on the content of organometallic compounds and heavy metals both directly in water and in biota [1]. Studies have shown that the Volkhov River is polluted with petroleum products from various sources in the cities of Kirishi, V. Novgorod, Volkhov with their removal to the waters of Lake Ladoga [2]. Oil and petroleum products tend to accumulate in bottom sediments and have a highly toxic effect on the ichthyofauna in early ontogenesis. Oil and petroleum products as sources of organometallic compounds have a particularly strong effect on benthic organisms, and in case of salvo intake – on fish grown by industrial methods. The migration of various forms of chemical ingredients in the biosphere organisms is a very complex system of many interconnected and to varying degrees closed cycles of elements in individual aquatic ecosystems. Ultimately, intra-aquatic relationships are reduced to the exchange of elements between organisms and the environment. In general, the differences in the biogeochemical cycle of trace elements are due to their concentration in the components of hydroecosystems, which occur in a certain ecotoxicological setting. Heavy metals as priority toxic substances have a high ability to actively penetrate into the most diverse substances of hydroecosystems: they are found in large quantities in water, soils, internal organs and bones of fish, and their parasites, other aquatic invertebrates, as well as plants [3]. Quantitative indicators of the occurrence and accumulation of metals in the waters and hydrobionts of Lake Ladoga are subject to large fluctuations. The degree of their concentration in the organs and tissues of fish and in the external environment is usually higher near the entry of industrial wastewater into the reservoir. Almost everywhere, a number of heavy metals are found in water, sediments and various organs and tissues of fish in quantities exceeding permissible standards. Due to exposure to dangerous toxic substances, the fish of Lake Ladoga are severely intoxicated at different stages of ontogenesis, which affects the vital activity of the body. In fish, toxicoses of varying severity, the appearance of neoplasms are recorded. With deep lesions of the vital systems of the body of fish, in some cases their death occurs.