scholarly journals Effects of Polymetallic Ore Occurrences on Mercury Accumulation by Aquatic Biota in River Ecosystems

2021 ◽  
Vol 14 (6) ◽  
pp. 766-776
Author(s):  
M. I. Shapovalov ◽  
V. A. Gremyachikh ◽  
V. T. Komov

Abstract The study represents the data on metal content in the body of stoneflies Perla pallida Guerin-Meneville, 1838 (Plecoptera, Perlidae) and in muscles of the fish family Cyprinidae from the small tributaries of the Belaya River (Republic of Adygea, Northwest Caucasus) with ore mineralization of various metals including mercury. It was found that mercury (Hg) concentrations in stoneflies are corresponds to from the water basins without local Hg sources. Mercury content in stoneflies depends on season and is more intensive in early ontogenesis in winter than in the warm season. Mercury concentration in 0.01–0.72 mg/kg dry weight can cause the pathomorphological changes in the structure of organs and decrease the adaptive potential in competitive population of stoneflies, in general. The Hg concentration reached 0.09–0.69 mg/kg in the studied fish species (bleak, gudgeons, and barbels) and was similar to concentrations in stonefly larvae. This can be related with low size-weight parameters of fishes in samples as wells as with similar feeding patterns of hydrobionts.

Author(s):  
Nadezhda Aleksandrovna Golubkina ◽  
Alisher Saidovich Hursanow ◽  
Tatiyana Sergeevna Ershova ◽  
Vyacheslav Fedorovich Zaitsev ◽  
Vladimir Aleksandrovich Chaplygin

The purpose of the research was to study accumulation of mercury and selenium in muscles and liver of Russian and Persian sturgeons caught in the Caspian Sea. Analysis of the data revealed preferential accumulation of mercury and selenium in liver compared to muscle tissues of both species. The article shows that the degree of mercury accumulation in the liver and muscles of the Persian sturgeon was higher than of the Russian. Correlation analysis of data showed that mercury content in the sturgeon liver and muscles statistically significantly depended on age, length and weight of the fish. In the course of these studies there has been identified a direct correlation between selenium content in muscle tissue and body weight of fish. The results of the analysis indicate that the accumulation of mercury and selenium in Persian and Russian sturgeon species is stipulated by their physiological characteristics and properties of the chemical elements. Mercury concentration in liver and muscles of the tested species is little, which corresponds to the standards adopted in Russia. The level of selenium in the liver increases with the concentration of mercury in it, which confirms the defensive function of selenium against heavy metals.


1968 ◽  
Vol 48 (2) ◽  
pp. 427-434
Author(s):  
A. E. BRAFIELD

1. The oxygen consumption of the echiuroid Bonellia viridis has been investigated by means of a continuous-flow polarographic respirometer. 2. The general rate of oxygen consumption per unit dry weight is similar to that characteristic of polychaetes, and declines exponentially with increasing body size. 3. The rate of oxygen consumption rises in the light and falls again if darkness is restored. 4. The oxygen consumption of the isolated proboscis plus that of the isolated body region corresponds closely to that of the entire animal. 5. The oxygen consumption per unit dry weight of the proboscis is considerably higher than that of the body region. 6. The oxygen consumption of an isolated body region increases in the presence of light, but that of an isolated proboscis does not. 7. These findings are discussed in relation to the biology of the animal, observed muscular activity, and the occurrence of the pigment bonellin.


2021 ◽  
Author(s):  
L.A. Yatsenko ◽  
N.V. Dzen ◽  
N.V. Gabbasova ◽  
N.P. Mamchik

Adaptive potential is an indicator of the level of adaptability of the human body to various and changing environmental factors. The adaptive capabilities of the body are influenced not only by external factors, but also by internal - the state of the body as a whole, by the presence or absence of chronic diseases. Therefore, the adaptive potential was used as an integral indicator of a person's adaptability to production factors. The aim of the study was to assess the adaptive capabilities of the organism of workers in greenhouse farms in the Voronezh region. The study was carried out at the enterprises of the closed ground of the region by the method of questioning, the objects of the study were 125 women aged 27-45 years. In most cases, there are violations of the adaptive capabilities of the organism among the studied workers of greenhouse farms, and even a breakdown in adaptation was revealed in 0.8%. In less than half of the cases, the adaptive potential of the greenhouses was within the normal. The adaptive reserves of the greenhouses workers decrease with age.


2021 ◽  
Vol 29 (1) ◽  
pp. 90-107
Author(s):  
Zdeněk Dolníček ◽  
Jana Ulmanová ◽  
Karel Malý ◽  
Jaroslav Havlíček ◽  
Jiří Sejkora

In the Pohled quarry near Havlíčkův Brod town (central part of Czech Republic), texturally and mineralogically simple contaminated anatectic pegmatites form dikes or irregular bodies cementing breccia of host metamorphic rocks (paragneisses, amphibolites) belonging to the Monotonous (Ostrong) Group of the Moldanubicum of the Bohemian Massif. They exhibit signs of intense hydrothermal overprint and also the presence of abundant disseminations, nests and veinlets of ore minerals. A detailed mineralogical study revealed the presence of an extraordinary rich ore assemblage (20 species in total, including one unnamed phase). The oldest minerals are sphalerite (rich in Fe), löllingite, Fe-Co-Ni sulphoarsenides (cobaltite, glaucodot, arsenopyrite, gersdorffite), pyrrhotite, galena and chalcopyrite, in later portion accompanied by inclusions of Bi-minerals (native bismuth, bismuthinite, joséite-A, joséite-B, ikunolite and a Pb-Bi sulphosalt). The composition of the Pb-Bi sulphosalt is equal to Ag,Fe-substituted eclarite; its identity was confirmed also by Raman spectrum. Pyrite is very abundant phase, present probably in several generations. The Fe-Co-Ni thiospinels disseminated in younger chlorite, and represented by siegenite, violarite, grimmite and an unnamed NiFe2S4 phase, are the youngest ore minerals. The mineral association as well as chemical composition of most ore minerals are well comparable to those of local polymetallic ore veins and Alpine-type veins, which give evidence for identical origin of all these ore mineralizations. The formation of pegmatite-hosted ore assemblage was long-lasting multiphase process, which took place at temperatures between ca. 350 and <120 °C during changing fugacities of sulphur, tellurium and oxygen. A distinct enrichment in cobalt and nickel of ore mineralization hosted by pegmatites (in comparison with hydrothermal veins) is explained in terms of pronounced interactions of fluids with amphibolites and serpentinites.


2020 ◽  
Vol 28 (1) ◽  
pp. 47-56
Author(s):  
Elena S. Ivanova ◽  
Anastasia I. Kornilova ◽  
Olga Yu. Rumyantseva

The research was conducted in 2018 and 1323 women of childbearing age from the city of Cherepovets in the Vologda region took part in it. The Hg content in the hair of women was determined on a RA-915M mercury analyzer. The average concentration of metal in the hair of residents was 0,427 0,015 mg/kg. A positive correlation was found between mercury accumulation and age ( r = 0,288), fish consumption, and blood biochemical parameters - erythrocytes (RBC) ( r = 0,097), hemoglobin (HYB) ( r = 0,172) and hematocrit (HCT) ( r = 0,158) with p 0,05.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Xiaoyi Guo ◽  
Wei Zhou ◽  
Qun Lu ◽  
Aiyan Du ◽  
Yinghua Cai ◽  
...  

Dry weight is the normal weight of hemodialysis patients after hemodialysis. If the amount of water in diabetes is too much (during hemodialysis), the patient will experience hypotension and shock symptoms. Therefore, the correct assessment of the patient’s dry weight is clinically important. These methods all rely on professional instruments and technicians, which are time-consuming and labor-intensive. To avoid this limitation, we hope to use machine learning methods on patients. This study collected demographic and anthropometric data of 476 hemodialysis patients, including age, gender, blood pressure (BP), body mass index (BMI), years of dialysis (YD), and heart rate (HR). We propose a Sparse Laplacian regularized Random Vector Functional Link (SLapRVFL) neural network model on the basis of predecessors. When we evaluate the prediction performance of the model, we fully compare SLapRVFL with the Body Composition Monitor (BCM) instrument and other models. The Root Mean Square Error (RMSE) of SLapRVFL is 1.3136, which is better than other methods. The SLapRVFL neural network model could be a viable alternative of dry weight assessment.


Author(s):  
Tat’yana A. Fisher ◽  
◽  
Svetlana S. Kolyvanova

The aim of this paper was to study changes in the haemodynamic and psychophysiological parameters of working age men as a result of repeated exposure to contrasting temperatures, depending on the type of autonomic regulation. Materials and methods. The research involved 14 men (aged 34.77 ± 5.66 years; office workers) divided into two groups according to Kérdö index: those with the sympathetic (n = 8) and parasympathetic (n = 6) types of self-regulation. Cold conditioning followed a certain plan of exposure to contrasting temperatures. The haemodynamic and psychophysiological parameters as well as adaptive potential were assessed 20 minutes before and 20 minutes after the exposure (alternating temperature cycles). We examined the following parameters: heart rate, systolic and diastolic blood pressure, pulse and mean arterial pressure, stroke volume, cardiac output, vascular resistance, and adaptive potential according to Baevsky. Integral psychophysiological parameters were determined using the Lüscher express method. Results. Subjects with predominance of sympathetic regulation both before and after the exposure to contrasting temperatures had higher values of heart rate and cardiac output and lower vascular resistance than the parasympathicotonic group. Individuals with predominance of parasympathetic regulation showed decreased cardiac output and a significant increase in vascular resistance after the exposure compared with the initial data. We found statistically significant differences in the integral parameters “heteronomy/autonomy” and “balance of personal traits” between the groups under study before the conditioning procedures. The research indicates that repeated exposure to contrasting temperatures not only affects the haemodynamic parameters, but also changes the psychophysiological parameters, motivated behaviour in particular. For citation: Fisher T.A., Kolyvanova S.S. Effect of Repeated Exposure to Contrasting Temperatures on the Body of Working Age Men with Different Types of Autonomic Regulation. Journal of Medical and Biological Research, 2021, vol. 9, no. 4, pp. 394–404. DOI: 10.37482/2687-1491-Z077


2019 ◽  
Vol 48 (2) ◽  
pp. 165-173 ◽  
Author(s):  
Agnieszka Grajewska ◽  
Lucyna Falkowska ◽  
Andrzej Reindl

Abstract Mercury enters the body of seabirds in its most toxic organic form, i.e. methylmercury, mainly via the alimentary tract. Inside the body, mercury is transformed into less toxic forms and accumulates in the internal organs. The process of mercury removal from the body, most effective during the formation of new feathers and claws, is beneficial for the bird. The presented research was undertaken on account of the high affinity of mercury to keratin – a protein that forms feathers and claws – to compare the concentration levels (HgTOT) in these structures and to assess their contribution to the purification of the body of herring gulls (Larus argentatus) Bird feathers are the only epidermal structure that is extensively described in the literature, whereas the claws have so far been poorly researched. The study has shown that mercury in claws is built in as effectively as in feathers, and the obtained concentrations were within a wide range of 127.2–5341.5 ng HgTOT g–1 of dry weight. In addition, the concentrations of total mercury accumulated in the claws were a better reflection of Hg levels in internal organs compared to feathers.


2003 ◽  
Vol 60 (7) ◽  
pp. 888-896 ◽  
Author(s):  
Martin Kainz ◽  
Marc Lucotte ◽  
Christopher C Parrish

Relationships between organic matter (OM) compounds and methyl mercury concentrations ([MeHg]) have been examined in littoral and offshore sediments of Lake Lusignan (Québec). The highest [MeHg] were generally found at the sediment–water interface with exceptionally high concentrations at littoral sites (5.8 ± 1.3 ng·g dry weight–1), which were four times more elevated than at offshore sites (1.6 ± 0.77 ng·g dry weight–1). Source-specific fatty acid (FA) biomarkers identified that littoral sediments contained more than twice as much terrestrial and bacterial OM compounds than offshore sediments, whereas the amount of labile algal OM was three times higher at littoral sites. Results indicate that [MeHg] were higher in the presence of labile OM substrates, and the amount of terrestrial OM compounds could not predict [MeHg]. Correlations between [MeHg] and FA of Desulfovibrio desulfuricans (a sulfate-reducing bacterium producing MeHg) could significantly account for 36% of [MeHg] at offshore sites; however, no significant relationships were found at littoral sites. This study illustrates that the microbial dynamics involved in producing and degrading MeHg in lacustrine sediments are complex and cannot be predicted solely by the quantification of FA biomarkers in D. desulfuricans or by biomarkers in the OM itself.


2020 ◽  
Vol 10 (12) ◽  
pp. 4342
Author(s):  
Camilla Roveta ◽  
Daniela Pica ◽  
Barbara Calcinai ◽  
Federico Girolametti ◽  
Cristina Truzzi ◽  
...  

Porifera are filter-feeding organisms known to bioaccumulate different contaminants in their tissues. The presence of mercury (Hg) has been reported in different Mediterranean species, mainly collected in the southern coast of France. In the present study, mercury concentrations in the tissue of the sponges of Montecristo and Giglio, two islands of Tuscany Archipelago National Park (TANP), are presented for the first time. Analyses of total mercury content were performed by Direct Mercury Analyzer. Statistical differences have been reported in the Hg concentrations of species collected in both islands, but they do not appear related to the anthropic impacts of the islands. Among the collected species, a high intra- and inter-variability have been recorded, with Cliona viridis showing the lowest concentration (0.0167–0.033 mg·kg−1 dry weight), and Chondrosia reniformis and Sarcotragus spinosulus the highest (0.57 ± 0.15 and 0.64 ± 0.01 mg·kg−1 dry weight, respectively). The variability of Hg measured did not allow us to identify sponges as bioindicators of toxic elements. Anyway, these results improve knowledge on the ecosystem of the TANP, underlining the species-specificity of metal concentrations for Porifera, and providing additional data to address the main input of the Marine Strategy guidelines to protect coasts, seas and oceans.


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