The Mercury and Low Molecular-Weight Antioxidants Levels in Ungulates of the Republic of Karelia

The high toxicity of mercury (Hg) poses a danger to the environmentand humans, but studies of the concentration of this metal in organismsof terrestrial ecosystems are few. Ecotoxicologists also pay little attentionto studying the role of antioxidant vitamins in protecting cellsfrom toxic metals. The Republic of Karelia is one of the northwesternregions of Russia, the biogeochemical features of which can contributeto an increase in the mobility and bioavailability of Hg in foodchains. The purpose of the work was to determine the concentrationof Hg in the liver, kidneys, muscle and hair of ungulate mammalsof the Republic of Karelia (wild boar Susscrofa L. and moose Alces alces L.)and to analyze the relationship between the level of this toxicmetal and the content of low molecular-weight antioxidants—reducedglutathione, retinol and α-tocopherol. Species and tissue-specificof the studied parameters in wild boars and moose are noted. Theobservations discovered by other researchers that omnivorous speciesaccumulate more Hg in their tissues compared to herbivores, andalso that this toxic metal is predominantly accumulated in the kidneys,while muscles contain a minimal amount, have been confirmed. Hgconcentrations in most samples of liver and kidney of wild boarsand in all samples of the same organs of moose were within the limitsrecorded for domestic pigs and deer, respectively. The levels ofHg we recorded in the tissues and hair of wild boars and moose weregenerally comparable to or lower than the levels of this metal notedin animals from other regions of Russia and other countries of the world.In wild boars and moose of Karelia, no statistically significantrelationships were found between the Hg level and the content ofthe studied antioxidants in the internal organs. Moose were characterized bya higher content of α-tocopherol in the body than wild boars, whichis a feature of this type of herbivorous ungulate mammal. The resultsof the study indicate a relatively low level of mercury pollutionin terrestrial ecosystems in Karelia.