Accumulation Of Trace Elements Research Articles

Trace Element Accumulation in Two Turtle Species, Malaclemys terrapin and Chelydra serpentina, in New Jersey, USA.

Trace elements in aquatic environments pose a risk to biological communities; this study investigates the total concentrations of arsenic (As), silver (Ag), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), selenium (Se), lead (Pb), and zinc (Zn) within muscle, carapace, liver, and adipose tissues of diamondback terrapins and common snapping turtles in New Jersey. The effects of tissue type, sex, size, and location upon trace element accumulation were studied. The data obtained indicates that within diamondback terrapins and common snapping turtles, trace element accumulations displayed a significant difference among tissue types and sex (p < 0.005). The data indicates that Ag, Cd, Cu, and Hg can accumulate within the liver of diamondback terrapin. Se was found to accumulate in the livers of both diamondback terrapin and common snapping turtles. The highest mean concentrations of Co, Cr, Ni, and Pb were found in the carapace of both turtle species. Sex was found to have an impact on As, Hg, and Zn accumulation within different tissue types of diamondback terrapins. Diamondback terrapin males were found to have higher concentrations of As within the carapace. Diamondback terrapin females possessed higher concentrations of Hg in muscle tissues and Hg and Zn in the carapace. Turtle size and collection location land type and land cover did not display any correlation with trace element bioaccumulation for either species.

Estimation of tilapia fish quality in Lake Edku through physiological analyses regarding trace element accumulation, antioxidant enzymes, proximate composition, and human health risk assessment as the ultimate consumer

Lake Edku is one of the most important northern lakes whose people with limited income depend on its fish as a cheap source of food. In 2016, the Egyptian government has developed a strategy to develop the historical and economic value of northern lakes included Edku Lake within the Egypt vision 2030. That is why this study was conducted to monitor the physiological state of tilapia fish caught by different fishermen around the Edku lagoon. The results reported that the highest concentration was for As in O. aureus (2.16±0.3μg/g), which increased the safe limits permitted by FAO/WHO, EU' and the EOSQC. S. galilaeus was recorded the lowest Hg level (0.35±0.1 μg/g). The results estimated that the highest mean carbohydrate (13.85±1.26), fats (22.26±1.32), and water content (77.66±0.62%) were found in O. aureus. Otherwise, the largest ash (10.66 ± 1.72%) and protein (65.16±1.27) concentrations were recorded in S. galilaeus. The current study showed that S. galilaeus had the highest activity of antioxidant enzymes in the liver. The present study suggested that the children should intake less than 18.51g/day or 129.62g/week O. niloticus muscle, 13.761g/day or 96.33 g/week O. aureus muscle, and 16.66g/day or 116.66 g/week S. galilaeus muscle. Youth, on the other hand, should consume no more than 49.38g/day or 345.67g/week O. niloticus muscle, 36.69g/day or 256.88g/week O. aureus muscles, and 44.44g/day or 311.11g/week S. galilaeus muscle. Finally, adults should intake fewer than 84.65g of O. niloticus muscle per day or 592.59g per week, 62.90g of O. aureus muscle per day or 440.36g per week, and 47.61g of S. galilaeus muscle per day or 333.33g per week.

Mineralogy and geochemistry of clay fractions in soils developed from different parent rocks in Limpopo Province, South Africa

This study investigates the mineralogical and geochemical characteristics of clay fractions in soils developed from different parent rocks in Limpopo Province, South Africa using the X-ray diffraction (XRD), X-ray Fluorescence (XRF) Spectrometry, Laser Ablation – Inductively Coupled Plasma – Mass Spectrometry (LA-ICP-MS), Fourier Transform Infrared (FTIR) Spectrophotometry, Thermogravimetric Analysis and Differential Scanning Calorimetry (TGA-DSC) analytical techniques. Health risk associated with the presence of some trace elements was also investigated. The results revealed that the clay fractions had kaolinite as the dominant clay component occurring with other weatherable minerals. The crystallinity based on FTIR for the soil kaolinites correspond to partially - poorly ordered structures. The geochemical data showed appreciable accumulation of trace elements in the clay fractions. The absence of negative Ce anomaly in the chrondrite-normalised rare earth elements (REE) pattern in the clay fractions suggest the alteration of the primary minerals took place under suboxic conditions. The average non-carcinogenic hazard index (HI) were 1.52, 1.08, and 2.01 for children and 0.18, 0.13, and 0.24 for adults in the clay fractions from basalt, granite, and arkosic sandstone, respectively. The HI > 1 for children suggest non-carcinogenic health risk to children with ingestion pathway contributing the highest. The average carcinogenic risk index values were >10−3 for children and adults with respect to Cr, Ni, and Pb in the clay fractions. This suggests very high carcinogenic risk to children and adult population in decreasing order from clay fractions in arkosic sandsone > basalt > granite, respectively.

Evaluation of trace element contents and human health risk assessment via consumption of Liza aurata from the southern coasts of the Caspian Sea, Iran

Knowledge of the effects of trace element accumulations in fish tissues on consumer health is of great importance. Concentration of trace elements (Hg, Pb, Cr, Cd, As, Fe, Zn, Mn, Co, Cu, Ni, Al, Sn, Ti, V) were determined in muscle of Liza aurata, wild fish caught from the southern coasts of the Caspian Sea in 2014 and 2015 in order to understand the accumulation pattern of trace elements in this fish and to assess the potential health risk posed by fish consumption. Following the standard instructions, the preparation and chemical digestion of the samples were performed using an atomic absorption spectrophotometer (AAS). The highest and lowest accumulations in the muscle belonged to Fe and V (13.988 ± 3.4 and 0.0009 ± 0.00079 µg g-1 wet weight) respectively. The accumulations of these elements were lower than the permissible range proposed by the WHO for human consumption. Results showed that element accumulations were not affected by sex. Negative correlation coefficients were found between Pb, Cd, As, Zn, Al, Cu, Mn and V levels in the tissues and the fish weight and total length. Moreover, in this study, the value of the hazard index (HI) was calculated to be 0.065. Estimated daily intakes (EDIs) of the elements were in the range of 0.0045 to 7.5934 for adults, and 0.021 to 36.675 for children, while the target hazard quotients (THQ) was below 1.0 for each element. These results exhibit that the consumption of the investigated L. aurata from the southern coasts of the Caspian Sea does not cause significant adverse health effects. However, some considerations should be observed regarding the consumption of fish by infants and pregnant women.

Composition of chemical elements in the biosubstrate (hair) of children of the Karaganda region

In the article we studied chemical elements in the hair of children as a form of environmental monitoring of metals in a given area, since one of the objective indicators of the ecological and hygienic well-being of a territory is the status of trace elements as the most sensitive part of the population, especially children. Many foreign scientific studies have shown that a hair sample is a good indicator of a negative technogenic impact on humans, and it is known that the unfavorable state of children characterizes the ecogeochemical features of the area, so we took into account the accumulation of trace elements in the hair. The study showed an increase in lead and cadmium and a decrease in zinc, copper and chromium.

Assessment of trace element accumulation on the Tunisian coasts using biochemical biomarkers in Perinereis cultrifera

Our study aimed to evaluate the effect of trace element pollution in the polychaete Perinereis cultrifera (Grube, 1840) from two Tunisian coasts (the port of Rades, S1; and the Punic port of Carthage, S2). To this end, we used an approach based on proximate composition, biomarker responses and trace element bioaccumulation. Our results showed a decreasing order of metals concentrations (Zn&gt;Cu&gt;Cd&gt;Pb) in P. cultrifera from S1 and S2. The accumulation of Cd, Cu and Zn was significantly higher in S1 than in S2, especially in summer. Lipid, protein and glycogen content also changed significantly between S1 and S2 in relation to trace metal accumulation and environmental conditions. The results revealed a higher level of thiobarbituric acid in P. cultrifera from S1 than from S2. In addition, the enzymatic and non-enzymatic antioxidant defence system (catalase, glutathione-S-transferase, superoxide dismutase, glutathione and metallothionein) was enhanced and acetylcholinesterase activities decreased in P. cultrifera in S1 in comparison with S2. A principal component analysis showed that P. cultrifera from S1 exhibited a clear disruption of oxidative stress responses and trace element bioaccumulation among seasons. Overall, these findings revealed the sensitivity of those organisms to environmental conditions.

Sedimentological-Geochemical Data Based Reconstruction of Climate Changes and Human Impacts from the Peat Sequence of Round Lake in the Western Foothill Area of the Eastern Carpathians, Romania

This paper presents the results of comparative sedimentological and geochemical analysis of the mire at Sânpaul, Round Lake (Kerek-tó). The palaeoecological site is situated in the western foothill area of the Eastern Carpathians in Romania. The primary objective of this study was to analyse the accumulation of major and trace elements in a 7500 year-long peat and lake deposition. The concentrations of 13 elements were determined by using handheld XRF. This paper presents the results of a multidisciplinary study, for which the principal aims were to examine the long-term relationship between land degradation in the Homoród Hills using various palaeoecological techniques, primarily comparative geochemical analyses. The PCA of elemental concentrations suggests that Round Lake is mainly controlled by the input of inorganic mineral matter and the LOI550 of peat. However, some elements are influenced by biological processes of vegetation and groundwater. Geohistorical studies compared with vegetation changes and elemental distribution helped the detection of erosion phases in the level of 12 prehistoric cultures.

Soil and plant growth response and trace elements accumulation in sweet corn and snow pea grown under fresh and carbonated coal fly ash amendment

AbstractWith the recent focus of using coal combustion residue fly ash in mineral carbonation for C capture, an end product, carbonated coal fly ash is generated. The physicochemical changes occur in fly ash during carbonation is hypothesized to improve its soil application potential compared to original fly ash. Therefore, in the present study, we tested carbonated coal fly ash against non‐carbonated (fresh) ash for its effect on soil, plant production, and elemental accumulation in plant parts. Plant pots of sweet corn (Zea mays L.) and snow pea (Pisum sativum L.) added with fresh or carbonated Australian coal fly ash to sandy loam Podosol soil at 5% (w/w) and 10% (w/w) mixing rates were used in the study. Alkalinity of fly ashes attenuated the strong acidity of the soil into weakly acidic to slightly alkaline ranges. Either fresh or carbonated fly ashes added trace elements such as B, Fe, Mn, Zn, Cu, Cd, Mo, Cr, Pb, and Ni into the soil which significantly enhanced the plant growth and yield compared to fly ash absent pots. Accumulation of heavy metals in plant parts were observed in fly ash‐treated pots. Fresh fly ash at 10% (w/w) application rate increased the soil salinity above admissible range and retarded the crop growth and yield. Carbonated fly ash continued to enhance the crop production of sweet corn and snow pea up to 10% (w/w) mixing rate. Carbonation has improved the fly ash from its original state to make it a safer soil amendment at higher dosages such as 10% (w/w).

Evaluation of trace metal accumulation in six vegetable crops intercropped with phytostabilizing plant species, in a French urban wasteland.

The extensive development of agriculture in urban and peri-urban wastelands polluted with several trace elements (TE) poses risks to human health through contaminated food products. The objective was to explore the accumulation of TE in the various parts of vegetable crop plants (tomato, French bean, radish, potato, spinach, and leek) intercropped with phytostabilizing plant species (ryegrass and white clover, respectively). Field studies were conducted in a multicontaminated French urban wasteland with Cd, Cu, Pb and Zn, and an alkaline soil pH. Analyses of the respective non-edible parts of monocultured vegetable crops showed accumulation of all TE, mostly Zn, then Pb and Cu, and finally Cd. The corresponding TE accumulation factors (soil to plant) were all below 0.25. In the edible parts, average concentrations for TE were above the limit values, according to European and Chinese standards. TE contents in the phytostabilizing species chosen were in the same orders of magnitude and the same ranking as described for vegetable crops and most accumulation was in the roots. Unexpectedly, the presence of the phytostabilizing plants had a very strong positive impact on the soil to plant accumulation factor. Moreover, the edible plant parts were poorly impacted by the co-cropping with phytostabilizing plants.

Accumulation of Major, Minor and Trace Elements in Pine Needles (Pinus nigra) in Vienna (Austria).

Increasing heavy metal pollution in the environment and the fact that pine needles are good bio-monitors for air pollutants was the reason to investigate their accumulation in pine needles in Vienna (Austria). Pinus nigra is widespread over the city, thus allowing the study of different parameters influencing metal accumulation. The sampling sites were chosen based on traffic volume (low, medium, high). Fresh shoots were collected alongside one-year-old needles once per week from May to August 2015. The needle samples were washed and dried prior to acidic microwave-assisted digestion followed by quantitative determination using spectrometric methods. The investigation was focused on the following elements: Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Se, Sr, U, V, and Zn. The one-year-old needles mainly contained higher contents of elements than fresh shoots; in many cases, the values differed statistically significantly. By correlating needle elemental contents with the sampling site, statistically significant differences were registered for the majority of the investigated elements. These differences originate from the local traffic situation, soil elemental levels, translocation processes, and not traffic-related sources. No general trend of metal accumulation from spring to summer was registered.

MIGRATION OF MICROELEMENTS AND HEAVY METALS IN THE SYSTEM «SOIL - PLANT - PLANT-BASED PRODUCTS»

In Russia, raw materials of plant origin are used in the production of national beverages and food products. Many plots for the cultivated crops are located near urbanized areas, oil refineries, and machine-building plants. The research focuses on determining the concentration of heavy metals in soil in urbanized and rural areas. The content and transition of heavy metals to rhubarb and its processed product - kvass produced by various technologies have been identified as well. The purpose of this study is to determine the content of certain trace elements and heavy metals in soil, rhubarb, and its processed product - kvass made in different ways. The level of copper and lead in soil in rural areas has been found to be considerably higher than in the city. The concentration of cadmium and zinc is higher in the urbanized area. In the soils of rural and urbanized areas, the concentration of all the metals studied is sure to be higher than in the background levels. This indicates that soil contamination is caused not only by natural presence of elements but anthropogenic pollution as well. In analysis of transition and character of trace element accumulation in a soil-plant system, there is a strong link between the level of Pb, Cd in the soil and a plant (r = 0.81 and 0.71; respectively). In analysis of transition and character of trace element accumulation in a soil-plant system, there is a strong link between the level of Pb, Cd in the soil and a plant (r = 0.81 and 0.71; respectively). In the course of the study we found a symbateness between the content of trace elements in the soil and rhubarb: a reliable very strong, close to functional, direct link between the level of Zn, Pb and Cu (r = 0.97; 0.90 and 0.67, respectively; at р &lt;0.05). When studying the cross-environments transition of trace elements from soil to plants, a significant direct weak bond was established only for Cu (r = 0.31), Zn (r = 0.33) and Pb (r = 0.35). In the raw material-product system, there is a reliable symbateness between the level of metal in kvass and the concentration in vegetable crops in terms of Zn (r = 0.32), Cu (r = 0.46) and Cd (r = 0.38). No other reliably significant links have been established. Plant material produced according to organic production principles and the processing technology we’ve developed contribute to both the least impact on its constituent parts and the increased macro- and microelements content, the content of toxic elements remaining within the limits of the existing regulatory documents.

Plant response to mycorrhizal inoculation and amendments on a contaminated soil

Understanding the combined effects of soil amendments and inoculation of mycorrhizal fungi on the response of different plant species during the phytostabilization process of trace elements contaminated soils is a challenge. This task is more difficult but more realistic when studied under field conditions. We assess the combined effects of two amendment doses and mycorrhizal inoculation on the response of saplings of two tree species planted in a contaminated field. The amendments were a mix of sugar beet lime and biosolid compost. The inoculation treatments were made with a commercial inoculum of arbuscular mycorrhizal fungi for wild olive and ectomycorrhizal fungi for stone pine. Results showed a weak or null effect of the mycorrhizal inoculation on plant growth, survival and trace element accumulation. There was a significant increase on P nutrition for stone pine, growing on non-amended conditions. Soil amendments were very effective reducing trace elements availability and their accumulation in both plant species, especially in roots. However, the effects on plant biomass were species-dependent and contrasted; low-dose amendments increased the biomass of wild olive by 33.3%, but reduced by 28% that of pine. The high doses of amendments (60 T ha−1) produced some negative effects on plant growth and nutrition, probably related to the increase of soil salinity. Both plant species, stone pine and wild olive, have been proved to be adequate for phytostabilization of contaminated soils under Mediterranean climate, due to their drought tolerance and the low transfer of trace elements from root to shoot, thus reducing toxicity for the food web. To implement microbial-assisted phytoremediation approaches, a better understanding of the diversity and ecology of plant-associated microorganisms is needed. The use of indigenous fungi, locally adapted and tolerant to contamination, would be more suitable for phytostabilization purposes.

ASSESSMENT OF TRACE ELEMENTS UPTAKE ON THE INVASIVE CRAB PORTUNUS SEGNIS HEPATOPANCREAS USING A MULTIVARIATE BIOCHEMICAL APPROACH

In the current investigation, we evaluated the biological consequences of trace elements contamination in the two Tunisian gulfs (Gabes gulf and Tunis gulf) on the blue swimming crabs hepatopancreas (Portunus segnis). The concentrations of three trace elements (cadmium, copper, and lead) in the hepatopancreas P.segnis were evaluated. Additionally, acetylcholinesterase (AChE), metallothioneins (MTs), hydroxide peroxidase (H2O2) and advanced oxidation protein products (AOPP) levels, were chosen as measurements to evaluate the environmental effects on the two crabs’ populations from different gulfs. Macromolecular (lipids, proteins, and DNA) were also determined in P.segnis hepatopancreas. The results of trace elements bioaccumulation in soft P. segnis hepatopancreas showed a high pollution in the Gabes gulf as evidence by significant accumulation of cadmium, cooper, and lead. These findings were confirmed by significant increases of metal pollution index (MPI) and metallothioneins (MTs) levels in the hepatopancreas of P. segnis from Gabes gulf than these from Tunis gulf. Consequently, the trace elements accumulation in P.segnis from Gabes gulf conduct to the generation of lipid peroxidation processes as documented by the high levels of H2O2and LOOH. A significant decrease of AChE activity was recorded in crabs collected from Gabes gulf as compared to these from Tunis gulf. The present study revealed depletion of proteins and lipids contents, while DNA showed significant degradation on crab hepatopancreas collected from Gabes gulf comparing to Tunis gulf. These evidences must be taken in consideration when using P. segnis as an ecological indicator species in the biomonitoring programs.

Trace Elemental Analysis of the Exoskeleton, Leg Muscle, and Gut of Three Hadal Amphipods.

Hadal trenches are the deepest areas worldwide. Amphipods are considered a key factor in hadal ecosystems because of their important impacts on the hadal environment. Amphipods have benthic habits, and therefore, serve as good metal biomonitors. However, little is known about the hadal amphipod metal accumulations. In the present study, Alicella gigantea, Hirondellea gigas, and Scopelocheirus schellenbergi were sampled from the New Britain Trench (8824m, 7.02S 149.16E), Mariana Trench (10,839m, 11.38N 142.42E), and Marceau Trench (6690m, 1.42N 148.74E) in the West Pacific Ocean, respectively. The elemental concentrations of the three hadal amphipods were subsequently investigated. Nine trace elements (V, Cr, Mn, Co, Ni, Se, Mo, Ag, and Cd) of three tissues (exoskeleton, leg muscle, and gut) of the hadal amphipods were detected by using inductively coupled plasma mass spectrometry (ICP-MS) method. The concentrations of Cr, Cd, and Mn were comparably higher among those nine examined elements. The greatest accumulations of the elements Cr, Ag, and V in the exoskeleton and leg muscle were observed in H. gigas, and elements Mn, Co, and Se showed the highest accumulations in the gut in H. gigas among the three hadal amphipods. In addition, comparisons of the leg muscle trace element accumulation between the hadal amphipods and non-abyssal and shallow water decapoda and amphipoda species showed that the hadal amphipods possessed comparably higher concentrations of the trace elements Cd, Co, Mo, Ag, and V. This finding suggested a bottom-up effect of food availability and indicated the effects of human activities within the hadal environments. This study reveals the trace element bio-accumulation of three hadal amphipods, and suggests that deep-sea amphipods are potential indicator species for trace element bioavailability in the deep-sea environment.

Trace Metals Do Not Accumulate Over Time in The Edible Mediterranean Jellyfish Rhizostoma pulmo (Cnidaria, Scyphozoa) from Urban Coastal Waters

Jellyfish as food represent a millennial tradition in Asia. Recently, jellyfish have also been proposed as a valuable source of protein in Western countries. To identify health risks associated with the potential human consumption of jellyfish as food, trace element accumulation was assessed in the gonads and umbrella tissues of the Mediterranean Rhizostoma pulmo (Macri, 1778), sampled over a period of 16 months along the shallow coastal waters a short distance from the city of Taranto, an area affected by metallurgic and oil refinery sources of pollution. Higher tissue concentrations of trace elements were usually detected in gonads than in umbrella tissue. In particular, significant differences in the toxic metalloid As, and in the metals Mn, Mo, and Zn, were observed among different tissues. The concentrations of vanadium were slightly higher in umbrella tissues than in gonads. No positive correlation was observed between element concentration and jellyfish size, suggesting the lack of bioaccumulation processes. Moreover, toxic element concentrations in R. pulmo were found below the threshold levels for human consumption allowed by Australian, USA, and EU Food Regulations. These results corroborate the hypothesis that R. pulmo is a safe, potentially novel food source, even when jellyfish are harvested from coastal areas affected by anthropogenic impacts.

Comparison of moss bag and native moss technique in monitoring airborne particulate and toxic elements

Introduction: In Vietnam, the government has invested in monitoring stations in a few big cities like Hanoi and Ho Chi Minh City, which have transportation centers and industrial zones, to assess and predict levels of air pollution. However, the main disadvantage of installing monitoring stations is the cost of investment for operations, maintenance, and equipment. It is also time-consuming to collect and analyze the results. Therefore, it is generally not suitable for the country as a whole.&#x0D; Methods: Using mosses to monitor air quality brings qualitative and quantitative data with simple, environmentally-friendly economic methods. Mosses have particular biological characteristics that make them very suitable adsorbents for a wide variety of chemical elements. When used as transplants like moss bags, allow them to monitor a highly dense sampling network of any site easily. Mosses are bioindicators, plants with artificial roots.&#x0D; Results: In this study, moss bag and native moss were the two methods used to evaluate the accumulation of trace elements in air through Barbula Indica. Observations showed that both methods could detect the same elements: Al, Si, P, S, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, Rb, Y, Sb, Ba, Pb, and U. However, the accumulation of the elements in native moss is higher than in moss bag. The main reason is that the absorption efficiency of native moss in air-deposited elements is higher than in moss bags.&#x0D; Conclusion: Moss bags have been used most extensively and successfully in urban areas, where vegetation samples are either unobtainable or are poorly located to the source. These areas can lack moss, or the native moss simply does not grow during the dry season.

Assessment of essential element accumulation in red swamp crayfish (Procambarus clarkii) and the highly efficient selenium enrichment in freshwater animals

The red swamp crayfish is an important aquatic food for humans. In this study, the accumulation of trace elements, such as manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), and selenium (Se) in the hepatopancreas, abdominal muscle, and exoskeleton of red swamp crayfish from four regions in China were investigated. The mean concentrations of Mn (21.01 mg/kg) and Fe (34.85 mg/kg) in the abdominal muscle were remarkably lower than those in the hepatopancreas (236.07 mg/kg and 2517.94 mg/kg) and exoskeleton (274.67 mg/kg and 111.34 mg/kg). The mean concentrations of Cu (19.62 mg/kg), Zn (73.95 mg/kg), and Se (1.04 mg/kg) in the abdominal muscle were remarkably higher than those (16.52 mg/kg, 21.79 mg/kg, 0.38 mg/kg) in the exoskeleton and lower than those (116.85 mg/kg, 124.74 mg/kg, 2.56 mg/kg) in the hepatopancreas, respectively. The concentrations of Cu (23.56 mg/kg) and Se (1.12 mg/kg) in the abdominal muscle of crayfish from the Ensi region were higher those in the other three regions. There was a highly significant positive correlation between the concentrations of Cu and Se in crayfish and those in the environment (r ≥ 0.68, P < 0.01). In addition, Se could be specifically enriched in the red swamp crayfish, and a similar situation was found in bighead carp and Chinese mitten crabs. These results highlight the level of intake of essential elements by humans. Importantly, the consumption of the abdominal muscles of crayfish does not result in the overdose of the five essential elements. Therefore, these findings provide new insights into food nutrition and safety control for the consumption of crayfish and other freshwater animals.

Influence of Mining Activities on Arsenic Concentration in Rice in Asia: A Review

Crop and livestock farming on contaminated soil has been found to induce the accumulation of trace elements in edible parts of plants, with subsequent risk to human and animal health. Since rice crop is a major source of energy in worldwide diets and is consumed by more than 3 billion people, the soil–rice pathway is regarded as a prominent route of human exposure to potentially toxic elements. This study provides an overview of arsenic contamination in paddy rice from mining-impacted areas in several Asian countries that are primary rice consumers. From this review, it may be concluded that mining activities, along with the associated residual waste, significantly contribute to arsenic contamination of this food crop as rice samples from these regions were highly contaminated, with the highest total arsenic concentrations recorded being 3–4 times higher than the maximum levels proposed by the Codex Alimentarius Commission. While the contamination in China, Korea, Indonesia, and Thailand appeared to be slightly affected by mining activities, the elevated levels of arsenic in rice from mining areas in India, Bangladesh, and Vietnam could be derived from arsenic-contaminated groundwater.

Effect of the temperature of different combustion zones in the boiler grate on changes in physical and chemical parameters of bituminous coal and slags

This paper presents the results of a study on the influence of the temperature of characteristic zones of coal combustion in a stoker fired boiler (drying, degassing, and burn-out), on changes in physical and chemical parameters of bituminous coal and slags. This information is important as it helps identify the impact of coal properties on the accumulation of trace elements, primarily mercury, in combustion waste. The study is the continuation of research work on the impact of mercury compounds accumulated in combustion waste on the natural environment (mercury from landfills of slag, and fly ash). Studies were undertaken because no in-depth analysis of the impact of the temperature of particular zones of stoker fired boilers on the physical and chemical parameters of the post-process slag, including mercury content, had been reported in literature. Both of the coals examined, classified as bituminous coal according to the International Classification of Seam Coals and of type 32.1 according to the PN-G-97002:1982 standard, showed an average mercury content of 0.0849 μg/g. In the chemical composition determined for the ash derived from burnt coal, the dominance of SiO2 and Al2O3 over other oxides was found. This feature results in the increase of the softening temperature and ash melting and, therefore, during the combustion of coal tested in a stoker fired boiler, only ash was subjected to the sintering process. Mercury content in the other examined samples taken from various locations of the stoker fired boiler (drying – 32–1050 °C, degassing – 1050–1020 °C, and burn-out – 1020–400 °C) varied from 0.0668 to 0.0009 μg/g and was determined with the use of a LECO atomic absorption spectrometer. The analyses of the elemental composition, performed with the application of XRF spectrometry, for ash obtained from samples collected from different sampling points of the stoker fired boiler showed that the largest concentration of trace elements was observed for the ash derived from the samples collected in the degassing zone (temperature range 1050–850 °C).

МИКРОЭЛЕМЕНТНЫЙ СОСТАВ ДЕРНОВО-КАРБОНАТНЫХ ПОЧВ СЕВЕРО-ЗАПАДНОГО КАВКАЗА

The aim of the work is to study the peculiarities of the formation of the microelement composition of sod-carbonate soils of the North-West Caucasus. Methods: Determination of the features of the formation of the microelement composition of sod-carbonate soils was carried out in the western part of the Labino-Malkinsky landscape district of forest-steppes and settled meadows. The Kuestov District occupies a band of ridges of the North-western Caucasus, composed of limestones, dolomites and sandstones of the Jurassic (K) and Cretaceous (k) periods. Chemical analysis of the soil was performed by conventional methods. The content of strongly bound compounds Pb, Cu, Zn, and Cd by acid decomposition using 5 M HNO3 was analyzed in the humus horizon of soils. The metal content was determined by the methods of inversion volt-amperometric and atomic absorption analyses. Results: In most cases, the microelement composition of sod-carbonate soils is characterized by the enrichment of Pb, Cu, Cd and depletion of Zn in comparison with the Clark soils. The constant anthropogenic input of pollutants into the soil as a depositing medium directly affects the trace element composition-the soils are intensively enriched with all the elements considered, especially strongly accumulated on CD and PB. In the radial distribution of trace elements between sod-carbonate soils and the soil-forming rock, a high intensity of accumulation of chemical elements in the humus horizon of soils was revealed. The intensity of the redistribution of trace elements in soils is largely determined by the position in the terrain. Within the Cretaceous cuesta, high Cd contents are typical for plakor soils, Cu and Zn-for the soils of the slope of the beam. On the slope of the Jurassic questi higher contents of Pb, Cd and Cu are typical for soils of placorestan cavage array Zn for soils of steep hillside with oak and beech forests. Conclusions: The microelement composition of sod-carbonate soils is a consequence of such soil-forming processes as humification, humus accumulation, leaching, glinting, and loess age, the specifics of which are largely determined by calcium carbonates. The microelement composition of sod-carbonate soils reflects the most significant features of the microelement composition of soil-forming rocks, which are characterized by low Zn content. The possible aerotechnogenic intake of trace elements affects the intensity of the radial accumulation of trace elements in the soil relative to the rocks. The degree of transformation of the microelement composition of anthropogenic disturbed soils depends on the intensity of anthropogenic impact on the soil. The conducted research is important in the aspect of revealing the regularities of the formation of the microelement composition of the soil as a depositing component of the landscape in modern conditions of anthropogenic pressure.