In present study, the analyses of essential [copper (Cu), cobalt (Co), selenium (Se) and zinc (Zn)] and non-essential elements [mercury (Hg), lead (Pb), cadmium (Cd) and arsenic (As)] in 7 fish species consumed by the indigenous people of the European Russia Arctic were conducted. The Nenets Autonomous Region, which is located in the north-eastern part of European Russia, was chosen as a Region of interest. Within it, the Nenets indigenous group (n = 6000) constitutes approximately 10% of the total population. Nearly all of the Nenets live a traditional life with fish caught in the local waters as a subsistence resource. We found that northern pike contained twice the amount of Hg compared with roach, and 3-4 times more than other fish species commonly consumed in the Russian Arctic (namely, Arctic char, pink salmon, navaga, humpback whitefish and inconnu). Fish Hg concentrations were relatively low, but comparable to those reported in other investigations that illustrate a decreasing south-to-north trend in fish Hg concentrations. In the current study, northern pike is the only species for which Hg bioaccumulated significantly. In all fish species, both Cd and Pb were present in considerably lower concentrations than Hg. The total As concentrations observed are similar to those previously published, and it is assumed to be present primarily in non-toxic organic forms. All fish tissues were rich in the essential elements Se, Cu and Zn and, dependent on the amount fish consumed, may contribute significantly to the nutritional intake by indigenous Arctic peoples. We observed large significant differences in the molar Se/Hg ratios, which ranged from 2.3 for northern pike to 71.1 for pink salmon. Values of the latter 1 appear to enhance the protection against Hg toxicity.

Sodium-ion battery technology rapidly develops in the post-lithium-ion landscape. Among the variety of studied anode materials, hard carbons appear to be the realistic candidates because of their electrochemical performance and relative ease of production. This class of materials can be obtained from a variety of precursors, and the most ecologically important and interesting route is the synthesis from biomass. In the present work, for the first time, hard carbons were obtained from Heracleum sosnowskyi, a highly invasive plant, which is dangerous for humans and can cause skin burns but produces a large amount of green biomass in a short time. We proposed a simple synthesis method that includes the pretreatment stage and further carbonization at 1300 °C. The effect of the pretreatment of giant hogweed on the hard carbon electrochemical properties was studied. Obtained materials demonstrate >220 mAh g⁻¹ of the discharge capacity, high values of the initial Coulombic efficiency reaching 87% and capacity retention of 95% after 100 charge-discharge cycles in sodium half-cells. Key parameters of the materials were examined by means of different analytical, spectroscopic and microscopic techniques. The possibility of using the giant hogweed-based hard carbons in real batteries is demonstrated with full sodium-ion cells with NASICON-type Na₃V₂(PO₄)₃ cathode material.

The current article describes the biological activity of new biomaterials combining the “green” properties of humic substances (HSs) and silver nanoparticles. The aim is to investigate the antioxidant activity (AOA) of HS matrices (macroligands) and AgNPs stabilized with humic macroligands (HS-AgNPs). The unique chemical feature of HSs makes them very promising ligands (matrices) for AgNP stabilization. HSs have previously been shown to exert many pharmacological effects mediated by their AOA. AgNPs stabilized with HS showed a pronounced ability to bind to reactive oxygen species (ROS) in the test with ABTS. Also, higher AOA was observed for HS-AgNPs as compared to the HS matrices. In vitro cytotoxicity studies have shown that the stabilization of AgNPs with the HS matrices reduces the cytotoxicity of AgNPs. As a result of in vitro experiments with the use of 2,7-dichlorodihydrofluorescein diacetate (DCFDA), it was found that all HS materials tested and the HS-AgNPs did not exhibit prooxidant effects. Moreover, more pronounced AOA was shown for HS-AgNP samples as compared to the original HS matrices. Two putative mechanisms of the pronounced AOA of the tested compositions are proposed: firstly, the pronounced ability of HSs to inactivate ROS and, secondly, the large surface area and surface-to-volume ratio of HS-AgNPs, which facilitate electron transfer and mitigate kinetic barriers to the reduction reaction. As a result, the antioxidant properties of the tested HS-AgNPs might be of particular interest for biomedical applications aimed at inhibiting the growth of bacteria and viruses and the healing of purulent wounds.

Exposure of Arctic residents to environmental pollutants is an emerging public health problem receiving little global attention. The objective of this study was to assess whole blood concentrations of nine selected essential (Co, Cu, Mn, Se, Zn) and non-essential (As, Cd, Hg, Pb) elements among Nenets and non-Nenets adult residents of the Nenets Autonomous Okrug (NAO) living in seven coastal and inland settlements. Urine was collected in two settlements for assessment of iodine status. Altogether 297 whole blood and 68 urine samples were analysed by inductively coupled mass spectrometry and the accuracy of the measurements was assessed by use of human whole blood and urine quality control materials. Several essential and non-essential showed significant variations in whole blood concentrations characterized by gender, population group and locality. Cd levels among non-Nenets non-smokers (0.19 µg/L) indicated a dietary intake at a natural global background level. Hg concentrations in whole blood show that not more than 10% of women in the fertile age had a Hg intake above the EFAS's recommendation. The Pb concentrations were in the range of, or partly exceeding reference values for increased risk of nephrotoxicity, and there is a need for a continued effort to reduce Pb exposure among the population groups in NAO. With high prevalence of obesity among the Nenets and non-Nenets population, a high prevalence of Fe-deficiency among menstruating women (<50 years) (37.2%) and a lower I status than recommended by WHO, these nutritional dependent components deserve further attention.

Persistent organic pollutants (POPs) are heterogeneous carbon-based compounds that can seriously affect human health. The aim of this study was to measure serum concentrations of POPs in women residing in the Euro-Arctic Region of Russia. A total of 204 women from seven rural settlements of the Nenets Autonomous Okrug (NAO) took part in the study. We measured serum concentrations of 11 polychlorinated biphenyls (PCBs) and 17 organochlorine pesticides (OCPs) across the study sites and among Nenets and non-Nenets residents. Measurement of POPs was performed using an Agilent 7890A gas chromatograph equipped with an Agilent 7000 series MS/MS triple quadrupole system. The concentrations of all POPs were low and similar to findings from other Arctic countries. However, significant geographic differences between the settlements were observed with exceptionally high concentrations of PCBs in Varnek located on Vaygach Island. Both ΣDDT (p = 0.011) and ΣPCB (p = 0.038) concentrations were significantly lower in Nenets. Our main findings suggest that the serum concentrations of the legacy POPs in women in the Euro-Arctic Region of Russia are low and similar to those in other Arctic countries. Significant variations between settlements, and between Nenets and non-Nenets residents, were found. Arctic biomonitoring research in Russia should include studies on the associations between nutrition and concentrations of POPs.

Currently, monitoring of persistent organic pollutant (POP) content in various biological and environmental matrixes in the Arctic is an urgent task. The present study focused on the determination of POPs such as: PCB#28, PCB#52, PCB#101, PCB#105, PCB#118, PCB#123, PCB#153, PCB#128, p,p’-DDE, o,p’-DDE, p,p’-DDD, o,p’-DDD, hexachlorobenzene (HCB), cis-nonachlor, trans-nonachlor, cis-chlordane, trans-chlordane, mirex, 1,2,3,5-tetrachlorobenzene and 1,2,4,5-tetrachlorobenzene in fish consumed by the indigenous people of the Nenets Autonomous Okrug (NAO) of the Russian Arctic. Fish samples were analyzed by gas chromatography triple quadrupole mass spectrometry (GC-MS/MS) using the multiple reaction monitoring (MRM) technique. The obtained results show that the major POPs in fish were dichlorodiphenyltrichloroethane (DDT) breakdown products and polychlorinated biphenyls (PCB) congeners. The ∑PCB₈ in pink salmon, Arctic char, navaga, humpback whitefish and northern pike were 1.54, 1.58, 1.24, 0.72 and 0.32 ng/g (ww), respectively. The main PCB congeners maximum average medium concentrations were 0.68 ng/g (ww) and 0.51 ng/g (ww) of PCB#153 in navaga and PCB#128 in pink salmon, respectively. The main DDT breakdown product was p,p’-DDE. In Arctic char, pink salmon, navaga, humpback whitefish and northern pike, the concentration of p,p’-DDE was 0.58, 1.61, 0.49, 0.63 and 0.08 ng/g (ww), respectively. A moderate positive relationship between ∑PCB₈ and lipid content and a high positive relationship between ∑DDT and lipid content were observed. In fish samples with fat content 1% (pink salmon, Arctic char). Despite the large number of fish in the diet of indigenous peoples from NAO, no significant risks were identified. Most legacy POP and organochlorine pesticides (OCPs) tend to decrease, which can be explained by past national and regional bans and restriction on their use and emission.