Mercury Content in Organs and Tissues of Indigenous (Vulpes vulpes L.) and Invasive (Nyctereutes procyonoides Gray.) Species of Canids from Areas Near Cherepovets (North-Western Industrial Region, Russia)

Abstract

Trophic and spatial components of ecological niches of two canids native Vulpes vulpes and introduced Nyctereutes procyonoides are overlapping partially in the studied region. Maximum concentrations of mercury in predatory mammals of Canidae family from surroundings of Cherepovets have been determined in liver and kidneys (over 0.50 mg/kg wet weight), with minimal concentrations in brain (<0.2 mg/kg wet weight). The amount of mercury in the same organs of the red fox and raccoon dog is not significantly different. These levels of mercury content are noticeably higher than those in the predators of Canidae family that inhabit territories of Europe lacking the local sources of mercury. At the same time, absolute values of metal quantity are commensurable with the levels registered in predators from the mercury polluted regions of Spain and Poland.

Mercury in Tissues of Red Fox as Indicator of Environmental Pollution

“…The level of mercury in the tissues of the fox from the area around a large metallurgical complex (Cherepovetsky district -3) is comparable to the concentration of mercury in the tissues of the fox from a specially protected natural area (Kirillovsky district -2) and an area significantly distant from industrial complexes (Verkhovazhsky district -1). The concentration of mercury in the muscles, liver and brain of foxes from the industrial region was confirmed by the data on the content of mercury in red foxes, previously studied in this area [13]. The average concentration of mercury in the muscles of the red fox from the Vologda region is 2 times higher than in the muscles of the fox from suburban areas of Croatia [4] and 3 times lower than in the muscles of the fox from regions contaminated with heavy metals in Spain, where for a long time there was a mining activity [15].…”

Mercury Content in Tissues of Amphibians of Northwest Russia (Vologda Region)

“…Obtained data on the distribution of mercury in amphibians matches with data from the literature on this issue: the maximum сontents of the metal are found in the liver and the kidneys, the minimal is seen in the muscles and skin [16]. Studies on mercury accumulation in organs and tissues of mammals also show the maximal mercury сontent to be found in the liver and kidneys, in other words, in the organs that perform the function of detoxification [17], [18], [19].…”

Secrets of the Astute Red Fox (Vulpes vulpes, Linnaeus, 1758): An Inside-Ecosystem Secret Agent Serving One Health

“…It is, therefore, necessary to trace the presence and the number of chemical substances, such as heavy metals and pesticides, in their tissues. Contaminants studies make it possible to understand the organic changes in the animal, but also the potential dangers for human health [13,14]. Contaminants' exposition, during long times and at low doses, can alter physiological processes (e.g., metabolism, hormonal changes), decrease animal body condition (e.g., small and weak animals), immunotoxic effects, decrease reproductive success (e.g., infertility, abortion, malformations), and can result in genotoxic and mutagenic effects (cancer) [8,15,16].…”