Mercury content in commercial fishes of the Barents Sea (based on long-term data)

Abstract

The aim: to study the amount of mercury found in muscle tissue and liver of the main commercial fish species of the Barents Sea.Research material was comprised of fish samples collected during the expeditions of “PINRO” named after Knipovich in the Barents Sea in 2009-2020. The study was based on muscle and liver samples taken from cod, haddock, long rough dab, Greenland halibut, plaice and spotted catfish. Over 1500 samples were analyzed. Novelty: for the first time a comparative analysis of Hg concentration in six commercial fish species of the Barents Sea was run and background readings were provided using such a big amount of data.Methods used: the total content of Hg in fish samples was measured using Shimadzu (Japan) Cold Vapor Atomic Absorption Spectrophotometer (CVAAS). Statistical data processing and charting were done using MS Excel and application software package of Statistica 13.Results: it was shown that the mean amount of Hg in muscle and liver of the studied fish was below the maximum concentration of 0.5 pg/g of wet weight acceptable by sanitary standards. Content of Hg in liver was two times higher than in muscle. No evidence of anthropogenic contamination of the studied species by mercury was found. The total content of Hg in muscle and especially in liver demonstrated a considerable variability, which is probably linked to seasonal changes in the diet. There might be other factors influencing the mercury concentration, such as taxonomic affiliation, regional peculiarities, physiological state, and fattiness.Practical significance: the acquired results were used to determine whether the commercial fishes meet the sanitary standards used in Russia.