Distribution Of Mercury Research Articles

Distribution of Mercury in Drained Peatlands as the Effect of Secondary Transformation of Soil Organic Matter

Peat organic soils play a major role in the accumulation of soil organic matter (SOM) and the mercury (Hg) cycle. Large mercury resources in peatlands can be a source of methylmercury for many decades and centuries, even if deposition is significantly reduced. The organic matter of peatland soils drained for agricultural use is subject to secondary transformation, which may affect the accumulation and resources of mercury. The aim of our work is to assess the secondary transformation of organic matter in the soils of drained peatlands of the temperate climate zone and to examine whether it affects mercury resources and profile distribution in organic soils. Field research was conducted in peatlands located in eastern Poland. In the present study, evaluation of secondary transformations occurring after drainage was based on observations of soil morphological characteristics, physical and chemical properties as well as fractional composition of organic matter of the identified soil horizons (to depth 70 cm). Standard cold vapor atomic absorption spectrometry (CV-AAS) was used to measure the total mercury content. In our research, we found a significant effect of the secondary transformation of organic matter occurring in drained peatlands of the temperate climate zone on the total mercury content and stock in soils. The highest content and differentiation of mercury occurred in murshic horizons (up to a maximum depth of 43 cm). The average mercury content of the distinguished soil horizons is grouped in the following series (in μg kg−1): M1 (212.0) > M2 (182.8) > M3 (126.3) > Pt (84.9). The mercury stock, up to a depth of 70 cm in the tested soils, ranged from 17.5 to 39.6 mg m−2. As much as 82.2% of soil mercury was found in the upper murshic horizons. We found strong correlations between soil properties characteristically variable in the secondary transformation process and total mercury content. The increased content of humic substances in murshic horizons caused a significant increase in the total mercury content. Our research is of great importance for soil monitoring, as the amount of determined mercury was greatly influenced by the depth of sampling (up to 25 cm). The results of the research should be taken into account when planning the restoration of peatlands of the temperate climate zone. There is a potential risk that elevated mercury concentrations in the upper murshic horizons may be a source of methylmercury for a long period of time. In peat soils with a high concentration of mercury, the risk of contamination with this toxic metal should be determined before re-irrigation.

Impacts of anthropogenic discharge on distribution, mass budget, and long-term risk of total mercury in coastal region: A case study of the Jiaozhou Bay, China

Mercury (Hg) as a toxic pollutant in marine systems have been paid more attention. The Jiaozhou Bay (JZB) is located at the western coast of the Yellow Sea surrounded by Qingdao city, a developed city in China. >10 rivers and several sewage treatment plants carry lots of Hg input it, increasing the environmental risks JZB facing. However, there is still a lack of knowledge on its cycling in the JZB, limiting sound understanding of Hg fate in coastal regions. To address these needs, four cruises were conducted in different seasons, to investigate distribution, influencing factors, and mass budget of total Hg (THg) in the JZB. Higher THg concentrations were determined in seawater (22.8 ± 13.9 ng L−1) and sediment (148 ± 107 ng g−1), indicating serious Hg pollution in the JZB. Temperature, salinity in water and enrich factor (EF) in sediment were identified to be possible environmental factors influencing THg distribution in the JZB. Mass budget of THg showed that anthropogenic discharge (river, wastewater input, and atmospheric deposition) was dominant source of THg in the JZB. The results of statistical analyses and mass budget of THg also indicated that anthropogenic discharge plays important roles in long-term risk of THg in the JZB. These results suggested that anthropogenic discharge comprehensively affects distribution, mass budget, and long-term risk of THg in coastal systems. The outcomes highlighted that regular investigations of Hg cycling should be conducted to assess Hg pollution in coastal ecosystems. Our study also shed new light on control of long-term risk posed by Hg in marine systems according to investigations of Hg cycling and link between Hg contamination and other pollutant (e.g., nutrient).

Geospatial Distribution of Mercury in Surface Soils Across Ghana

Geospatial Distribution of Mercury in Surface Soils Across Ghana

Mercury distribution inthe great cormorant (Phalacrocorax carbo) from the Krogulna ponds and Nysa Kłodzka River (Poland).

Mercury belongs among the highly hazardous substances present inthe environment and represents agreat health risk for many animals including predatory and piscivorous birds. The aim ofthis study was toassess the total mercury content inthe main detoxifying organs (liver and kidney) and inthe muscles ofadult great cormorants (Phalacrocorax carbo) caught attwo localities (the Krogulna ponds and the Nysa Kłodzka River) insouthern Poland. The aim was tocompare the locality with the iron ore mining history (the Krogulna ponds) with asite without such load (the Nysa Kłodzka River). The total mercury content inthe great cormorants decreases asfollows: kidneys> liver> muscle inboth monitored localities and significantly differs between the localities. Theaverage mercury content varied from 0.58±0.38mg/kg (muscle) to1.39±1.42mg/kg (kidney) inthe cormorantfrom the Krogulna ponds and from 1.09±0.40mg/kg (muscle) to3.12±1.55mg/kg (kidney) inthe cormorant from the Nysa Kłodzka River. The accumulation ofmercury does not correlate with the mining history asit was higher atthe Nysa Kłodzka River, but itis probably influenced bythe different fish stocks inthese two localities (omnivorous fish inthe Krogulna ponds versus predatory fish inthe Nysa Kłodzka River).

Spatial distribution of Hg in Pra River Basin, Southwestern Ghana using HF acid combination method

The study assessed the spatial distribution of total mercury (THg) in soils, sediments, mining wastes, and Au-rich Hg-contaminated tailings from artisanal and small-scale gold mining (ASGM) from Offin, Lower and Upper Pra, Birim, and Anum Rivers, Pra River Basin, Southwestern Ghana. THg measurement using Cold Vapor Atomic Absorption Spectrometry (CVAAS) after acid digestion with HNO3/HCl/HF and k0-INAA, as a reference method, and both provided comparable results. A digestion method, HNO3/HClO2/H2SO4 acid mixture before CVAAS provided lower results, which indicates that the use of HF is of fundamental importance in THg analysis based on acid digestion and its omission may significantly underestimate the presence of Hg in soils and sediments. THg in soils, sediments, Au-rich Hg-contaminated tailings, and mining wastes from the river basin were liberated into a solution for measurement using HNO3/HCl/HF. The study revealed Offin and Lower Pra Rivers showed high distribution (ranges; mg Hg kg-1) of THg in soils (103-770) and sediments (0.20-20.8), respectively; Upper Pra and Anum rivers showed the lowest THg in soils (2.20-3.20) and sediments (0.004-0.02), respectively. About 76.0% of THg in sediments was lower than the USEPA guideline of 0.2mg Hg kg-1. The highest mean THg (mg Hg kg-1) in Au-rich Hg-contaminated tailings (1673 ± 4.8, n = 4) and mining wastes (17.3-21.5) were from the river Offin. The study showed Offin (Dunkwa-on-Offin site 1) and Lower Pra (Beposo Township) rivers are Hg hotspots that need attention.

A new hazard assessment workflow to assess soil contamination from large and artisanal scale gold mining

Gold mining activities are undertaken both at large and artisanal scale, often resulting in serious ‘collateral’ environmental issues, including environmental pollution and hazard to human and ecosystem health. Furthermore, some of these activities are poorly regulated, which can produce long-lasting damage to the environment and local livelihoods. The aim of this study was to identify a new workflow model to discriminate anthropogenic versus geogenic enrichment in soils of gold mining regions. The Kedougou region (Senegal, West Africa) was used as a case study. Ninety-four soil samples (76 topsoils and 18 bottom soils) were collected over an area of 6,742 km2 and analysed for 53 chemical elements. Robust spatial mapping, compositional and geostatistical models were employed to evaluate sources and elemental footprint associated with geology and mining activities. Multivariate approaches highlighted anomalies in arsenic (As) and mercury (Hg) distribution in several areas. However, further interpretation with enrichment factor (EFs) and index of geoaccumulation (IGeo) emphasised high contamination levels in areas approximately coinciding with the ones where artisanal and small scale mining (ASGM) activities occur, and robust compositional contamination index (RCCI) isolated potentially harmful elements (PHE) contamination levels in very specific areas of the Kedougou mining region. The study underlined the importance of complementary approaches to identify anomalies and, more significantly, contamination by hazardous material. In particular, the analyses helped to identify discrete areas that would require to be surveyed in more detail to allow a comprehensive and thorough risk assessment, to investigate potential impacts to both human and ecosystem health.

An example of artificial neural networks modeling the distribution of mercury (Hg), which poses a risk to human health in the selection of settlements: Sarayönü (Türkiye)

An example of artificial neural networks modeling the distribution of mercury (Hg), which poses a risk to human health in the selection of settlements: Sarayönü (Türkiye)

Distribution and bioavailability of mercury in size-fractioned atmospheric particles around an ultra-low emission power plant in Southwest China

Ultra-low emission (ULE) technology retrofits significantly impact the particulate-bound mercury (Hg) emissions from coal-fired power plants (CFPPs); however, the distribution and bioavailability of Hg in size-fractioned particulate matter (PM) around the ULE-retrofitted CFPPs are less understood. Here, total Hg and its chemical speciation in TSP (total suspended particles), PM10 (aerodynamic particle diameter ≤ 10 µm) and PM2.5 (aerodynamic particle diameter ≤ 2.5 µm) around a ULE-retrofitted CFPP in Guizhou Province were quantified. Atmospheric PM2.5 concentration was higher around this ULE-retrofitted CFPP than that in the intra-regional urban cities, and it had higher mass Hg concentration than other size-fractioned PM. Total Hg concentrations in PM had multifarious sources including CFPP, vehicle exhaust and biomass combustion, while they were significantly higher in autumn and winter than those in other seasons (P < 0.05). Regardless of particulate size, atmospheric PM-bound Hg had lower residual fractions (< 21%) while higher HCl-soluble fractions (> 40%). Mass concentrations of exchangeable, HCl-soluble, elemental, and residual Hg in PM2.5 were higher than those in other size-fractioned PM, and were markedly elevated in autumn and winter (P < 0.05). In PM2.5, HCl-soluble Hg presented a significantly positive relationship with elemental Hg (P < 0.05), while residual Hg showed the significantly positive relationships with HCl-soluble Hg and elemental Hg (P < 0.01). Overall, these results suggested that atmospheric PM-bound Hg around the ULE-retrofitted CFPP tends to accumulate in finer PM, and has higher bioavailable fractions, while has potential transformation between chemical speciation.

Аккумуляция ртути в двустворчатых моллюсках в гидроэкосистеме устьевой области реки Красная (Вьетнам)

The article presents analysis of mercury content in different tissues such as gills, mantle, hepatopancreas and body (leg) in 4 species of bivalve molluscs in the estuary of the Red River in Vietnam. The studies were carried out in 2016–2021 during the main hydrological seasons (during the summer flood and winter low water) at 37 stations in the delta and estuarine coast of the Red River. There are shown the dependences of mercury content in mollusc tissues on the age parameters (length and mass of tissues) and on the content of pollutant in dissolved, suspended forms of near-bottom water layers and in bottom sediments. The mercury content in the tissues of molluscs varies whithin 0,023 ± 0,001 to 0,459 ± 0,007 mg/kg wet weight. The highest content of mercury was found in the hepatopancreas &#x0D; of Austriella corrugata, and the lowest - in the leg of Lutraria rhynchaena. Significant close positive correlations were registered between the mercury concentrations in the mollusc tissues and the mercury content in the near-bottom water layer and in bottom sediments (r from 0.68 to 0.92, p &lt; 0.05). All studied species of molluscs are classified as macroconcentrators of mercury in water; Austriella corrugata can actively accumulate mercury not only from the water, but also from the bottom sediments. Bivalve molluscs can be used as an object of biomonitoring when studying the distribution of mercury in the estuary of the Red River.

Quantifying Mercury Distribution and Source Contribution in Surface Soil of Qinghai-Tibetan Plateau Using Mercury Isotopes.

Long-range transport and atmospheric deposition of gaseous mercury (Hg0) result in significant accumulation of Hg in the Qinghai-Tibetan Plateau (QTP). However, there are significant knowledge gaps in understanding the spatial distribution and source contribution of Hg in the surface soil of the QTP and factors influencing Hg accumulation. In this study, we comprehensively investigated Hg concentrations and isotopic signatures in the QTP to address these knowledge gaps. Results show that the average Hg concentration in the surface soil ranks as follows: forest (53.9 ± 36.9 ng g-1) > meadow (30.7 ± 14.3 ng g-1) > steppe (24.5 ± 16.1 ng g-1) > shrub (21.0 ± 11.6 ng g-1). Hg isotopic mass mixing and structural equation models demonstrate that vegetation-mediated atmospheric Hg0 deposition dominates the Hg source in the surface soil, with an average contribution of 62 ± 12% in forests, followed by 51 ± 10% in shrub, 50 ± 13% in steppe, and 45 ± 11% in meadow. Additionally, geogenic sources contribute 28-37% of surface soil Hg accumulation, and atmospheric Hg2+ inputs contribute 10-18% among the four types of biomes. The Hg pool in 0-10 cm surface soil over the QTP is estimated as 8200 ± 3292 Mg. Global warming, permafrost degradation, and anthropogenic influences have likely perturbed Hg accumulation in the soil of QTP.

Simulation of mercury distribution in an offshore natural gas processing platform

In this work, the distribution of mercury in an offshore natural gas processing platform in Norway is simulated, and the results are compared to field measurements regarding elemental and total mercury concentration in process fluids. The effect of a possible reaction between mercury and H2S that leads to solid β-HgS formation is also examined. For the simulation, the UMR-PRU group-contribution equation of state (EoS) and the SRK cubic EoS are employed, which have been extended to mercury mixtures in our previous works. The results show that both models satisfactorily predict mercury concentration in process gases, while they overpredict mercury concentration in condensates as compared to the field measurements. When the reaction is also considered, the predicted mercury concentrations in condensates are closer to the measured values. Overall, it is concluded that both models can satisfactorily predict the distribution of mercury in a gas processing plant.

Spatial distribution and risk assessments of mercury in topsoils of Central Asia

Central Asia is one of the largest arid areas on earth, yet little is known about the concentration levels and risks of mercury (Hg) in the soils of this region. In this study, extensive sampling of topsoils (0–10 cm) from representative landscapes was carried out over Central Asia (i.e., Tajikistan, Uzbekistan, and Kyrgyzstan). The total mercury (THg) concentrations in topsoils varied widely from 1.6 to 908.0 ng/g, with high values observed in samples collected in the capital cities and urban areas. Topsoil THg concentrations among different landscapes showed a decreasing order of urban (79.8±184.0 ng/g) > woodland (27.3±28.9 ng/g) > grassland (20.6±15.9 ng/g) > farmland (18.3±9.5 ng/g) > desert (12.3±8.0 ng/g). High THg concentrations were found in the capital cities/urban clusters, followed by a gradual decrease towards the peripheries. THg concentrations were found to be negatively correlated with the distance from the sampling sites to their nearest cities, indicating that anthropogenic emissions significantly influenced the spatial distribution of topsoil Hg. A significant correlation between THg concentrations and topsoil total organic carbon (TOC) contents was also observed, suggesting that TOC played an essential role in the spatial distribution of topsoil Hg. The assessments of pollution and potential ecological risk suggested that topsoils in highly densely-populated areas were contaminated by Hg and had higher degrees of potential ecological risks. The health risk assessment results showed that the exposure risk of topsoil Hg to children was higher than that to adults. Fortunately, there was no unacceptable human health risk of topsoil Hg. This study clarified the spatial distribution and risks of Hg in the Central Asian topsoils, offering new insight into the risk prevention and control of soil Hg.

Atmospheric mercury in forests: accumulation analysis in a gold mining area in the southern Amazon, Brazil.

The spatial distribution and dispersion of mercury (Hg) is associated with the structural conditions of the environment, primarily land use and vegetation cover. Man-made emissions of the metal from activities such as artisanal and small-scale gold mining (ASGM) can influence this distribution. Forest ecosystems are of particular importance as they constitute one of the most active environments in the biogeochemical cycle of Hg, and understanding these dynamics is essential to better understand its global cycle. In this study, we determined the content of Hg present in different forest strata (soil, leaf litter, herbaceous, underwood/bush, and arboreal), as well as the relationship between the presence of Hg and the landscape heterogeneity, percentage of gold mines, and ground slope. This study was carried out in tropical forest areas of the southern Brazilian Amazon. Accumulation and transport of Hg between forest strata was assessed in order to understand the influence of these forest environments on Hg accumulation in areas where ASGM occurs. We verified that there is a difference in Hg content between forest strata, indicating that atmospheric Hg is accumulated onto the arboreal stratum and transported vertically to strata below the canopy, i.e., underwood/bush and herbaceous, and subsequently accumulated in the leaf litter and transferred to the soil. Leaf litter was the stratum with the highest Hg content, characterized as a receptor for most of the Hg load from the upper strata in the forest. Therefore, it was confirmed that Hg accumulation dynamics are at play between the areas analyzed due to the proximity of ASGMs in the region. This indicates that the conservation of forest areas plays an important role in the process of atmospheric Hg deposition and accumulation, acting as a mercury sink in areas close to man-made emissions.

Plastics and Five Heavy Metals from Sea Beaches: A Geographical Synthesis of the Literary Information

Pollution of the oceans and seas, as well as their coastal zones, with plastics has become serious challenge, which is also related to the Anthropocene marine geology and geochemistry. Notably, plastics can bear heavy metals. The related knowledge is scattered through scientific publications, and, thus, it needs generalization. The present study synthesizes the published information about the geographical distribution of cadmium, chromium, mercury, nickel, and zinc associated with plastics on sea beaches. A bibliographical survey is undertaken, and the collected literary information is organized so as to document the principal localities of beached plastics bearing these metals. About twenty localities are established in many parts of the world, and the majority of them correspond to the coasts of the Atlantic and Indian oceans and their seas. Significant attention has been paid by the previous researchers to Northwest Europe and South and East Asia. The available information is enough to postulate the global extent of the problem of heavy metals association with plastics on beaches. Real or potential risks to the environment were reported in many cases. This review also shows that the industry of tourism, hospitality, and recreation contributes to the accumulation of such plastics. The analyzed literary information demonstrates several biases: for instance, Hg-bearing plastics on beaches were reported from the smaller number of localities relatively to the other metals, and the beaches and coastal recreational areas of many regions are yet to be studied in regard to heavy metals associated with plastics.

Accumulation and distribution of mercury in agricultural soils, food crops and associated health risks: A case study of Shenda gold mine-Geita Tanzania

Contamination of the environment and foodstuff by potentially harmful elements (PHEs) has become a serious concern due to the associated health risks to the population. In the present study total mercury (Hg) levels in soil and food crops from farms around Shenda gold mine in Geita Tanzania was determined by Cold Vapor Atomic Fluorescence Spectrometry (CVAFS). Generally, it was found that there was significant different of Hg content in soil and food crops (P < 0.05) among studied sites. The total Hg concentrations determined were in the ranges of; soils (0.003-0.1220 mg/kg), rice (0.0752-0.1587 mg/kg) and vegetables (0.0556-0.3439 mg/kg) all measurement were based on dry weight basis (dw). Total Hg levels in soil were compared with the maximum allowable concentration (MAC) set by Tanzania Bureau of Standards (TBS) and United Kingdom (UK). All studied soil samples were within acceptable range (2 mg/kg) set by TBS and UK (1 mg/kg). Total Hg contents in food crop samples were compared with Chinese MAC of Hg (0. 01 and 0.02 mg/kg for leafy vegetables and grains respectively in a fresh weight basis). It was observed that Hg contents in potato leaves, pumpkin leaves and Chinese cabbage were within the MAC while Hg levels in cassava leaves and rice grains exceeded the MAC. In addition, Hg associated health risks to consumers of contaminated foods for residents around Shenda gold mine were estimated. The estimated weekly intake (EWI) of Hg due to consumption of rice grain was above the provisional tolerable weekly intake (PTWI) set by FAO/WHO (1.6 mg/kg bw/week) while the EWI due to consumption of leafy vegetables were below the PTWI. Target hazard quotient (THQ) was < 1 due to consumption of vegetables while THQ value for rice was >1, indicating a potential non-carcinogenic risk to adult population from the consumption of rice grain from the study area. Therefore, people living near Shenda goldmine might be potential victim of Hg accumulation in soil and food crops, thus necessary management options have to be in place.

Organic Carbon Controls Mercury Distribution and Storage in the Surface Soils of the Water-Level-Fluctuation Zone in the Three Gorges Reservoir Region, China.

The particular condition of the water-level-fluctuation zone (WLFZ) in the Three Gorges Reservoir (TGR), the largest hydroelectric reservoir in China, raises great concerns about mercury (Hg) contamination and ecological risk. In addition, previous research found that soil organic carbon (SOC) plays an essential role in controlling Hg distribution and speciation. However, there is minimal information on the Hg storage distribution and their relationships with SOC in the WLFZ in TGR. This study investigated Hg distribution, storage, and their relationships with SOC in the surface soils in WLFZ. The results showed that the total Hg (THg) content in the surface soils ranged from 18.40 to 218.50 ng g-1, with an average value of 78.17 ± 41.92 ng g-1. About 89% of samples had THg content above the background value in Chongqing, showing specific enrichment of Hg in WLFZ due to contamination in the TGR. The surface soils have low SOC, with an average value of 8.10 ± 3.90 g kg-1. Moreover, THg content showed consistent distribution with the SOC in WLFZ, with a significantly positive correlation (R = 0.52, p < 0.01, n = 242). THg storage (201.82 ± 103.46 g ha-1) in the surface soils was also significantly positively correlated with the SOC storage (R = 0.47, p < 0.01, n = 242). The reduced SOC sequestration, due to the periodical alternative "flooding-draining" and frequent reclamation and utilization of WLFZ, decreased the Hg adsorption in soil. Those might result in the re-release of Hg into waters when WLFZ is flooded. Therefore, more attention should be directed towards Hg cycling and the consequent environmental risks in the TGR region.

New geochemical data for defining origin and distribution of mercury in groundwater of a coastal area in southern Tuscany (Italy)

A geochemical study was conducted in a coastal plain in the Orbetello Lagoon area in southern Tuscany (Italy), acquiring new data on groundwater, lagoon water, and stream sediment for insights into the origin, distribution, and behaviour of mercury in a Hg-enriched carbonate aquifer. The main hydrochemical features of the groundwater are ruled by the mixing of Ca–SO4 and Ca–Cl continental fresh waters of the carbonate aquifer and Na–Cl saline waters of the Tyrrhenian Sea and Lagoon of Orbetello. Groundwater had highly variable Hg concentrations (< 0.1–11 μg/L) that were not correlated with the percentage of saline water, depth in the aquifer, or distance from the lagoon. This excluded the possibility that saline water could be the direct source of Hg in groundwater and responsible for release of the element through interaction with the carbonate lithologies of the aquifer. The origin of Hg in groundwater could be ascribed to the Quaternary continental sediments overlying the carbonate aquifer because i) high Hg concentrations were found in the continental sediments of the coastal plain and in the contiguous lagoon sediments; ii) waters from the upper part of aquifer had the highest Hg concentrations; iii) Hg levels in groundwater increased with increasing thickness of the continental deposits. The high Hg content in the continental and lagoon sediments is geogenic due to regional and local Hg anomalies and to sedimentary and pedogenetic processes. It can be assumed that i) water circulating in these sediments dissolves the solid Hg-bearing constituents and mobilises this element mainly as chloride complexes; ii) Hg-enriched water moves from the upper part of the carbonate aquifer due to the cone of depression generated by intense pumping of groundwater by fish farms in the study area.

Evaluation of arsenic, selenium, tin and mercury in water and sediments of Bitter Lakes, Suez Canal, Egypt

Surface water and surface sediment samples were collected from Bitter Lakes from winter to autumn 2018 to evaluate the impact of land-based activities on the distribution of arsenic (As), selenium (Se), tin (Sn), and mercury (Hg). The metal concentrations were measured in 12 sampling sites along Bitter Lakes in the Suez Canal by the hydride system MH10 coupled with an atomic absorption spectrophotometer. The most industrialized regions in the lake showed elevated levels of metals in the water and sediments compared to other studied areas. As, Sn, and Hg showed the highest levels in water during winter (9.66, 1.03, and 0.25 µg/l, respectively), while Se recorded its highest values during summer (2.60 µg/L). Similarly, the highest total concentrations of the investigated elements in the sediments were 22400.00, 605.85, 40.91, and 446.55 ng/g, respectively.

Content and distribution of mercury in coal and its relation to depositional environment—A case study on coals from the Shanxi Formation in Huainan Coalfield

Mercury in coals might emit into the environment from coal combination, and finally cause environmental pollution. In this paper, 26 coal samples were selected from No. 1 which is coal in the Shanxi Formation of Zhangji and Xinjier mines in the Huainan coalfield. The mineralogical and geochemical components of coal samples were determined by DMA-80 mercury-measuring instrument, XRF, XRD, ICP-MS, and the relationship between the depositional environment of the coal seam and mercury enrichment was analyzed. The results show that the mercury content of coal in the study area ranged from 0.03 to 0.93 μg/g, with an arithmetic means of 0.21 μg/g, higher than the background values of coal in China and the world. The mercury content of Shanxi Formation coal varied among different mines, the arithmetic mean value of mercury in Zhangji coal mine and Xinjier mine coal is 0.35 μg/g and 0.12 μg/g respectively. Due to the complex depositional environment and depositional facies, the distribution of mercury content in the coal seam is quite different. XRD, Microscopic observation and the ratio of (CaO + MgO + Fe2O3)/(SiO2+ Al2O3) and Al2O3/TiO2 show that the main mineral in the depositional environment of this study area is kaolinite, quartz and pyrite, and the depositional facies are intercontinental and sea-land, so the parent rock type belongs to acid bedrock. The Ni/Co, Sr/Ba, and Sr/Cu ratios were used to indicate a weak oxidation-reduction, Marine salt water, and an arid and hot environment. The vertical distribution of mercury in coal and the characteristics of the depositional environment are combined to show that mercury in coal is easily affected by redox conditions, paleosalinity and paleoclimate in the depositional environment. At the same time, mercury accumulation is more easily in the depositional environment dominated by seawater intrusion than in the terrigenous input.

ЗВ’ЯЗОК ГЕРМАНІЮ ІЗ ЗОЛЬНІСТЮ ТА «ТОКСИЧНИМИ» ЕЛЕМЕНТАМИ У ВУГІЛЛІ НА ПРИКЛАДІ ПЛАСТА с5 ПОЛЯ ШАХТИ БЛАГОДАТНА ЗАХІДНОГО ДОНБАСУ

Purpose. The character and level of the statistical relationship between the content of germanium and “toxic elements” in coal seam c5 of the “Blahodatna” mine and the main features of their distribution were established for the assessment of possible environmental risks during the selective processing of coal enriched with this element. It has been proven that the correlation between germanium and all “toxic” elements is inverse and very weak. The existence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium was revealed. Methods. The research materials included analysis of 38 coal samples for germanium, beryllium, fluorine, mercury and arsenic, performed in accredited state laboratories after 1981. The content of germanium, beryllium and fluorine was determined by quantitative emission spectral analysis, mercury and arsenic – by atomic absorption analysis. The samples were taken during the work of production enterprises and research organizations with the participation of the authors, using the furrow method of sampling in mine workings and from the core of wells from 1981 to 2018. For primary processing of geochemical data, STATISTICA 13.3 and IBM SPSS Statistics 22 were used to calculate basic statistical characteristics, including mean, standard error of the mean, median, kurtosis, mode, standard deviation, variance, minimum and maximum values, coefficient of variation, and sample skewness . Frequency histograms were created for visual assessment of the studied parameters, as well as the characteristics of their distribution were determined. To achieve the objectives of the study, correlation and regression analyzes were carried out using the functions available in Micromine – the leading professional mining and geological information system for 3D modeling, statistical data processing and mining planning. Results. It was established that a general feature of the distribution of ash content, germanium, arsenic, fluorine, mercury and beryllium in the c5 coal seam of the Blahodatna mine field is their non-compliance with normal and lognormal laws and the polymodality of the distributions with a shift of the density nuclei to the left, except for beryllium and germanium. Each of the studied elements in seam c5 of the “Blahodatna” mine accumulated in several forms, which differed significantly in their genesis. At the same time, the forms of finding, which are responsible for the minimum contents, were jointly accumulated at the initial, syngenetic stage. The presence of an inverse and very weak correlation between germanium concentrations and ash content, arsenic, fluorine, and mercury contents in the c5 coal seam of the Blahodatna mine was revealed. The only element considered that forms a very weak positive correlation with germanium is beryllium. Scientific novelty of the results. The presence of genetically different forms of germanium and arsenic, fluorine, mercury and beryllium in coal seam c5 of the Blahodatna mine was revealed. The polymodality of the distributions was established for all the considered components, while the displacement of the density of their distribution to the left was proved, except for germanium and beryllium. It has been proven that the correlation between germanium and ash content and all “toxic” elements (except beryllium) is inverse and very weak. Practical significance of the results. Justification of the method of the most accurate assessment of the central tendency in the distribution of a sample population of concentrations of germanium and arsenic, fluorine, mercury and beryllium in coal seam c5 of the “Blahodatna” mine. The presence of a very weak correlation between the content of germanium and “toxic” elements makes it possible to predict the minimal nature of possible environmental risks during the selective processing of germanium-enriched coal.