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We have demonstrated a highly sensitive novel platform for real-time detection of Mercury (Hg2+) ions after successfully making silver nanowires (AgNWs)-MoS2 nanocomposite and functionalizing it over ungated AlGaN/GaN high electron mobility transistor (HEMT). The AlGaN/GaN HEMT structures were grown over the sapphire substrate using Molecular Beam Epitaxy. AgNWs-MoS2 nanocomposites were optimized for the device functionalization and 1:4 ratio was found highly sensitive for Hg2+ ions. The sensor exhibits high sensitivity towards Hg2+ ions of 1.604 mA/ppb and calculated its Limit of Detection (LoD) up to the range of 20 ppt. The observed sensitivity is highest among previously reported AlGaN/GaN fabricated HEMT based sensors for Mercury (Hg2+) ions detection and is well below the standard permissible limits as set by World Health Organization (WHO) and Environmental Protection Agency (EPA). The enhancement in sensitivity is due to the enhanced surface to volume ratio of AgNW-MoS2 nanocomposite and the highly conductive nature of silver nanowires incorporated in MoS2. Moreover, we also performed sensing on real water samples of tap water and lake water. Further, we showed the smart sensing capability of our developed sensor by illustrating the Internet of Things (IoT) enabled system for next-generation heavy metal ion sensing.

Due to the water-insoluble nature of Hg0, its oxidization to Hg2+, which is water-soluble, is a viable approach for its effective removal at coal-fired plants using existing flue gas desulfurization (FGD) unit. In this study, the adsorption and oxidation of elemental mercury on an Mn-doped g-C3N4 material were investigated. The spin-polarized density functional theory method was adapted to optimize the geometry structures and then to determine the corresponding electronic structures, while the CI-NEB method was adopted to search for the stable intermediates during the reaction(s). The analysis of energy and project density of states shows that the Mn-g-C3N4 exhibits an excellent affinity to Hg atoms. It is found that it is feasible for Hg atoms to oxidize on the Mn-g-C3N4 surface via two possible E-R paths, but with relatively high energy barriers. This research provides insights into a viable way for mercury removal using O2 as the oxidizing agent.

The Steptoean Positive Isotopic Carbon Excursion, or SPICE event, was a globally recorded +2‰ to +6‰ shift in δ13C values during the later Cambrian (ca. 500 Ma). The excursion is associated with regional sea level change and trilobite extinctions documented from multiple paleocontinents, yet the mechanism(s) for these events and the excursion itself are not fully understood. Recent studies have suggested that the SPICE is accompanied by global changes in redox conditions, which may have served as an extinction driver. Here, we present new geochemical and mineralogical data from an outcrop of the SPICE located along the Port au Port Peninsula in western Newfoundland. We focus on paired sedimentary mercury and glauconite enrichments as a potential redox indicator in an effort to evaluate local redox conditions during the SPICE in Newfoundland and assess the validity of Hg as a redox proxy. These strata record small mercury enrichments (

The Welland Canal is the only source of raw water to the largest drinking water treatment plant in the Niagara Region in southern Ontario. The water of the Welland Canal has historically been contaminated from different sources, and identifying these potential pollutants to drinking water relies on direct chemical analysis that is time-consuming and costly to identifying the critical contaminants of concern. Therefore, the aim of this research is to access and prioritize the chemicals of concern and the possible sources of contamination impacting the Welland Canal water. Metals and organic contaminants originating from industrial effluent, agricultural runoff, Port Colborne STP effluent, Lake Erie sediments and antifouling paints on ship vessels are identified as major contributors of pollutant loads into the Welland Canal. Specifically, atrazine, glyphosate, metolachlor, TBT, mercury, lead and zinc are identified as major contaminants that could pose a health risk to over 300,000 residents in the Niagara Region.

Background: The nanocomposites are formed by introducing inorganic nano-clusters, fullerenes, clays, metals, oxides with numerous organic polymers. The assembly of these materials exhibits better properties such as catalytic, thermal stability and adsorption properties, etc. than the individual materials. Objective: The nanocomposite synthesized here by sol-gel method was primarily evaluated for cation exchange properties viz, elution concentration, elution behavior, effect of temperature on ion-exchange capacity. The synthesized composite was used as an electro-active component for fabrication of Hg2+ ion selective membrane electrode. Method : The sol-gel technique was used to synthesize multi-walled carbon nanotubes Zr(IV) phosphate composite cation exchanger. By the technique of solution casting the material as an electroactive part was used for the fabrication of mercury ion-selective membrane electrode. The potential response of the electrode was also investigated as a function of membrane composition and plasticizer. Results: The composite cation exchanger exhibited 1.8 meq g-1 ion-exchange capacity (IEC). It retained almost 65 % of its initial IEC upto a temperature of 400 °C. Distribution studies showed the selective nature of the composite for Hg(II) ions. The ion-selective membrane electrode exhibited typical Nernstian response towards Hg2+ ions in the concentration range 1×10-1 -1×10-7 M. Conclusion: The results discussed reveal that a new cation composite exchanger-multi-walled carbon nanotubes Zr (IV) phosphate exhibited excellent cation exchange properties and was found to be preferentially selective towards the Hg2+ ions. It was also used as an indicator electrode in the titration of Hg2+ using ethylenediaminetetraacetic acid as a titrant.

This work shows the technical feasibility to obtain uranium tetrafluoride through an electrochemical mercury cell. This technique represents a custom scaling-up methodology from our previous studies to obtain UF4 using the dropping mercury electrode cell. The UF4 products were obtained from natural UF6 gas, which was hydrolyzed to obtain a 50 g/L UO2F2 solution. The electrolysis cell was made using a mercury reservoir, to reach UF4 production rates of 1 Kg UF4/day. This custom design allowed a stable UF4 production thanks to the mercury cathode, which do not permit the accumulation of solid products in its surface. The cell was tested using current densities from 5.000 to 17.500 A/m2 and temperatures from 25 to 65 °C. The maximum current efficiency achieved under these conditions was 80%. The UF4 powders possessed spherical morphology, with diameters between 20 – 80 μm. Compared to the SnCl2 precipitation, this process did not allow preferential growth of the precipitates. This improved the compaction of the UF4 – Mg powders mixtures, with densities between 3.0 – 3.5 g/cm3. The purity of the UF4 products was over 98%.

We herein proposed a sample introduction technique based on solution cathode glow discharge (SCGD) of a portable design for inductively coupled plasma-optical emission spectrometry (ICP-OES) and its application in sensitive determination of mercury. The products from SCGD containing mercury vapor, were transported by an Ar flow to ICP spectrometer for detection. A gas liquid separator (GLS) and a dryer were used to condense and remove most of the accompanying moisture, which greatly improved both the stability and sensitivity of the signal. The detection limit (DL) acquired by this developed method was 0.22 μg/L (194.1 nm), which was nearly 82 times lower than that obtained by pneumatic nebulization (PN). The relative standard deviation (RSD) was 1.4% (n = 14) for a 50 μg/L standard. Blank solution (HNO3, pH 1) can effectively elute mercury residue. Its accuracy and practicality were also demonstrated by the determination of GBW10029 (fish) certified reference material, shrimp, crawfish, soil and human hair samples. The results showed good consistency with the certified values and the values obtained using inductively coupled plasma−mass spectrometry.

A simple and efficient dithizone-functionalized solid-phase extraction (SPE) procedure, online coupled with high-performance liquid chromatography (HPLC)-inductively coupled plasma mass spectrometry, was developed for the first time for enrichment and determination of ultra-trace mercury (Hg) species (inorganic divalent Hg (Hg(II)), methylmercury (CH3Hg(II)) and ethylmercury (C2H5Hg(II)) in cereals and environmental samples. In the proposed method, functionalization of the commercial C18 column with dithizone, enrichment, and elution of the above Hg species can be completed online with the developed SPE device. A simple solution of 2-mercaptoethanol (1% (V/V)) could be used as an eluent for both the SPE and HPLC separation of Hg species, significantly simplifying the method and instrumentation. The online SPE method was optimized by varying dithizone dose, 2-mercaptoethanol concentration, and sample volume. In addition, the effect of pH, coexisting interfering ions, and salt effect on the enrichment was also discussed. Under the optimized conditions, the detection limits of Hg species for 5 mL water sample were 0.15 ng/L for Hg(II), 0.07 ng/L for CH3Hg(II), and 0.04 ng/L for C2H5Hg(II) with recoveries in the range of 85%–100%. The developed dithizone-functionalized C18 SPE column can be reused after a single functionalization, which significantly simplifies the enrichment step. Moreover, the stability of Hg species enriched on the SPE column demonstrated its suitability for field sampling of Hg species for later laboratory analysis. This environment-friendly method offers a robust tool to detect ultra-trace Hg species in cereals and environmental samples.

The present study deal with determination of Se:Hg ratio in six fish species collected from Shatt Al-Arab river during the period June 2010 to Augest 2010. Muscles of the most important six commercial species of fish C. Carpio, B. luteus, L. abu, T. zilli, B. sharpeyi and T. ilisha have been analyzed after wet digestion with a mixture of concentrated acids (HClO4 / HNO3).The obtained results show that L. abu species having the highest Se:Hg ratio, while B. luteus species having the lowest Se:Hg ratio. Tissues analysis (skin, gills, kidney, liver, muscles) of B. sharpeyi reveals that skin accumulates the highest Se:Hg ratio levels, while muscles contained the lowest Se:Hg ratio. The values obtained are compared with literature data and selenium contents in fish muscle.

An environmental assessment of the Western Arabian Gulf Coastal regions was done by assessing heavy metals in sediments and seawater, as well as other environmental parameters. A total of 94 sediment samples and 94 water samples were collected from 22 locations to estimate 12 heavy metals in each sample. This was achieved by using Inductively Coupled Plasma-Optical Emission Spectrometer -ICP-OES and Direct Mercury Analyzer. In general, metals were significantly higher in sediment samples compared with water samples. The pollution index PI and sediments pollution index SPI proved that the study areas were unpolluted to slightly polluted with regard to sediments and water except for one location. Cadmium showed polluting levels in five sites of the studied area, thus it was considered as the most polluting heavy metal among the other studied metals. Zinc was contaminating two sites, while each of Mn, Cu, Pb, and Cr reached pollution levels in one site. On the other hand, Fe, Ni and Hg had non-polluting levels. The study revealed that about 82% of the Arabian Gulf western coasts are non-polluted to slightly polluted.

Background:: Compound Niuhuang Xiaoyan capsule is a realgar and cinnabar-containing traditional Chinese medicine, the contents of total arsenic and total mercury are found over regulation defined limits. However, only a small amount of arsenic in realgar and mercury in cinnabar are dissolved in the gastric juice, so the determination of soluble arsenic and soluble mercury is more significant than that of total arsenic and total mercury in Compound Niuhuang Xiaoyan capsule. Objective: : To study the contents of total arsenic, total mercury, soluble arsenic and soluble mercury in Compound Niuhuang Xiaoyan capsule. Method:: Microwave digestion and semi-bionic extraction were used to pretreat the samples of Compound Niuhuang Xiaoyan capsule, and the inductively coupled plasma mass spectrometry method was established to determine the contents of total arsenic, total mercury, soluble arsenic and soluble mercury in Compound Niuhuang Xiaoyan capsule. The accuracy of the established method was further evaluated by using a certified standard reference material prepared from dried citrus leaves (GBW10020(GSB-11)). Results: : The spiked recoveries were within 95-105 %. The R.S.D% of repeatability (N=6) and precision (N = 6) were below 5.0 %. The correlation coefficients of linear (R) for arsenic and mercury were both above 0.998. The limits of quantification (LOQ) were below 0.1 μg/L. The contents of As and Hg were defined in the dried citrus leaves and very near to the standard values provided by the manufacturer. The established method was applied to the analysis of three batches of Compound Niuhuang Xiaoyan capsule produced by three different manufacturers successfully. Insufficient realgar or cinnabar was formulated in some Compound Niuhuang Xiaoyan capsule samples. Conclusion: : The analysis showed that the contents of soluble arsenic and soluble mercury in artificial gastric juice were significantly less than that of total arsenic and total mercury in Compound Niuhuang Xiaoyan capsule. The results provided a reference for further study on the toxicology and pharmacokinetics of Compound Niuhuang Xiaoyan capsule.

Sediment samples from the Gomti River basin were investigated to determine and evaluate trace metal concentrations, their biological effect, and potential ecological and human health risks for adults and children. The mean concentrations of trace metals were organized in the descending order of mercury (Hg) (0.08 mg/kg) > chromium (Cr) (0.06 mg/kg) > lead (Pb) (0.05 mg/kg) > arsenic (As) (0.02 mg/kg) > cadmium (Cd) (0.01 mg/kg). The current study illustrated that metals were attributed to the area from natural sources and different anthropogenic sources especially from industries. However, the concentration levels were lower than the sediment quality guidelines (SQGs) based on the effect-range classifications of threshold effect concentration (TEC) and probable effect concentration (PEC). Therefore, the concentration of the elements showed no adverse biological effects on aquatic organisms. The evaluated potential ecological risk index also revealed the low toxicity to the aquatic environment. Moreover, the applied sediment quality indices, geo-accumulation index (Igeo), contamination factor (CF), and contamination severity index (CSI) suggested that the contamination levels of the elements were in the acceptable range, and the contamination had not notably impacted on the sediment quality. The risk index (HI) concerning age groups was significantly less than the threshold limit of 1 indicating that the contamination had no non-carcinogenic risk effect. The total carcinogenic risk (TCR) was less than a risk value of 1 × 10−4. Hence, the current study suggests that immediate remediation is not required due to an absence of alarming conditions in the study area. Proper monitoring of the attribution of the metal elements should be done for the betterment of human and environmental health.

We compared mercury bioaccumulation in triploid and diploid walleye (Sander vitreus) in Narraguinnep Reservoir, Colorado, USA, and made several hypotheses that sex- and ploidy-specific differences in the allocation of energy towards reproductive development would affect mercury bioaccumulation. We tested our hypotheses with linear regression and a bioenergetics model informed by field data. We found diploid walleye had 28%–31% higher mercury concentrations on average than triploids, but there were no differences between sexes of the same ploidy. Triploids of mature age exhibited minimal gonadal development when compared to diploids. After accounting for reproductive investment, the bioenergetics model accounted for most of the observed difference in average mercury concentration between ploidies for females. Conversely, the energetic cost of producing testes was low, and gonadal development could not explain observed patterns for males. Costs associated with elevated swimming activity and metabolism by diploid males relative to other groups could explain the difference but requires further investigation. The use of triploid fish in stocking programs could prove useful for reducing mercury in fish destined for human consumption.

Introduction. Mercury contamination is one of the most common environmental problems. The research objective was to study the qualitative composition and physicochemical properties of raw game meat obtained from the area near the Beloosipovo mercury deposit in order to define any possible contamination w ith xenobiotics. Study objects and methods. The research featured rib eye muscle tissue and soft flesh of elks shot on the hunting farms of the Kemerovo Region aka Kuzbass. Results and discussion. A complex set of experiments revealed the chemical composition of elk muscle tissue and flesh, as well as the mineral composition of elk muscle tissue. The samples were obtained from different parts of carcasses. The amino acid and fatty acid composition of elk muscle tissue made it possible to describe the biological value, mineral composition, and vitamin profile of elk meat. The physicochemical analysis included toughness, cooking losses, and moisture-retaining capacity, i.e. the properties that ensure juiciness. The research also featured the accumulation of xenobiotics in elk meat samples obtained from the biosinosis near the Beloosipovo merc ury deposit. Conclusion. The slaughter yield of elk meat was 51–53%, which exceeds the average yield of farm cattle meat by 4–6%. The moisture content was 73–78%, while the content of protein was between 20–24% and depended on the anatomical location of the muscle sample; the fat content reached 0.75–1.75%. The mercury accumulation at different storage temperature conditions ranged from 0.004 ± 0.001 to 0.009 ± 0.001 mg/kg, while the max imum allowable concentration of mercury is 0.03 mg/kg.

This study describes the residual mercury levels in canned fish marketed in Turkey. In total, 375 fish samples were analyzed by Inductive Coupled Plasma Optical Emission Spectrometry (ICP OES) for mercury residues. The quantification limit (LOQ) from the validation data ranged from 0.008 to 0.043 mg kg-1. Accuracy and precision were evaluated by means of recovery experiments at two concentration levels (30, and 50 μg L−1), obtaining recoveries between 87.5% and 109.3% and coefficient of variation below 10%. Also, the relative standard deviation (RSD) ranged from 0.2% to 9%. The expanded measurement uncertainty for mercury ranged from 11.1% to 19.2%. In investigated samples, 4.8% were detected at a detectable level of mercury, but these levels were below the legal limits. With regard to hg level were no significant correlations (p < 0.05) between species. According to Turkey's legislation, none of for example the maximum limit of 1.0 mg g-1 did not exceed the level, but 1.3% exceeded the limit recommended by the Food and Agriculture Organization/World Health Organization (0.5 ug g-1). The reproducibility limits obtained as a result of the validation study were found to be appropriate in accordance with both the NMKL 170 method and the Turkish Food Codex (Communiqué No: 2014/2), as well as the EU Commission Decision 2002/657/EC.

The Minamata Convention on Mercury is an international treaty with the objective of protecting human health by controlling and restricting mercury use and its release to the environment. Numerical modeling tools currently used to study the fate of mercury released to the atmosphere tend to answer questions such as ’what would be the result of a 50% decrease in mercury emissions from this region, or that emission sector?’. They are not generally designed to answer the questions of the type, ’How can a, say 25% reduction, in deposition be achieved for a particular terrestrial ecosystem/region or oceanic basin?’. This paper presents an optimization framework which exploits the numerical tractability and the real-time features of an emulator for Global Chemical Transport Mercury Models. The HERMES emulator uses the results of a large number of scenario simulations to provide the user in real-time the impact on mercury deposition resulting from changes in anthropogenic mercury emissions. The changes in emissions can be by emission sector, emission region or changes in the speciation of the emissions. The optimization framework extends the capabilities of the emulator to give the user the possibility to define a deposition reduction target in one or more regions, and the framework calculates the optimal set of emissions reductions from industrial macro-sectors considering all the geographical source regions. The user may set a maximum feasible emission reduction in each of the sectors or regions, and within these constraints the optimization framework calculates the minimum number of regions in which the emission abatement would need to be applied to achieve the target, or informs the user that the desired target is unattainable with the supplied constraints. The results from the case-study presented here not only demonstrate the need for action to implement the Convention to be concerted and coordinated internationally, but also the usefulness of an optimization framework to tailor policies for specific environmental targets.

Agricultural soils are under threat of toxic metal/metalloid contamination from anthropogenic activities, leading to excessive accumulation of arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg) in food crops that poses significant risks to human health. Understanding how these toxic metals and their methylated species are taken up, translocated, and detoxified is prerequisite to developing strategies to limit their accumulation for safer food. Toxic metals are taken up and transported across different cellular compartments and plant tissues via various transporters for essential or beneficial nutrients, e.g. As by phosphate and silicon transporters, and Cd by manganese (Mn), zinc (Zn), and iron (Fe) transporters. These transport processes are subjected to interactions with nutrients and the regulation at the transcriptional and post-translational levels. Complexation with thiol-rich compounds, such as phytochelatins, and sequestration in the vacuoles are the common mechanisms for detoxification and for limiting their translocation. A number of genes involved in toxic metal uptake, transport, and detoxification have been identified, offering targets for genetic manipulation via gene editing or transgenic technologies. Natural variations in toxic metal accumulation exist within crop germplasm, and some of the quantitative trait loci underlying these variations have been cloned, paving the way for marker-assisted breeding of low metal accumulation crops. Using plants to extract and remove toxic metals from soil is also possible, but this phytoremediation approach requires metal hyperaccumulation for efficiency. Knowledge gaps and future research needs are also discussed.

Recently, environmental pollution has become a serious concern worldwide. In this modern era, more Urbanization and Industrialization have led to the wide distribution of pollutants such as toxic chemicals, pesticides, petroleum products, and heavy metals in natural resources like water, soil, and air. Thus, it adversely affects plants and human beings. Currently, many heavy metals present in the environment in large amount like Cadmium, Lead, Arsenic, Mercury, and Nickel which cause a severe global environmental concern. They are more toxic to plants and human beings, as they mix with soil, they cause retardation in plant growth, reduce the nutritive value, affect photosynthesis, and also heavy metals pose harmful effects on human beings. In this review, we have summarized the adverse effect of heavy metals that alter plants' morphology, affects the germination of seeds, and growth of plants and summarized the effects of heavy metals on the humans which ultimately affects the human health.

Heavy metals are naturally occurring elements, but they are regarded as significant environmental pollutants due to their high density and high toxicity even at low concentrations. The aim of this paper is the evaluation of the pollution level of heavy metals in the river and riverbank sediments, as well as the estimation of their origin and spatial differences along the course of the Vrbas River through Banja Luka. The concentrations of metals have been assessed using the Inductively coupled plasma – optical emission spectrometry and Advanced mercury analyzer for mercury determination. The anthropogenic impact on heavy metal concentration in sediments was estimated by the calculating of pollution indices: geoaccumulation index (Igeo ), contamination factor (Cf ), pollution load index (PLI) and potential ecological risk index (Er). Obtained results indicate that there is no statistically significant spatial difference in metal concentration, indicating that heavy metals in sediments have a constant source. The anthropogenic impact expressed by the values of pollution indices showed that sites are generally uncontaminated by Co, Cr and V and moderately contaminated by Zn, Cu and Ni. On the contrary, lead, mercury and cadmium pose the highest ecological risk. The anthropogenic source of Pb, Hg and Cd is industry, municipal waste and the combustion of fossil fuels. The obtained results demonstrate the high ecological risk and the need for environmental monitoring, with the aim to support an efficient strategy to reduce local pollution and contamination of the investigated system. Тешки метали су елементи природног порекла, али се сматрају значајним полутантима животне средине због велике густине и токсичности, чак и при малим концентрацијама. Циљ овог рада је процена нивоа загађености речних и приобалних седимената тешким металима, као и процена њиховог порекла и просторне расподеле дуж тока реке Врбас кроз Бањалуку. Концентрације тешких метала одређиване су помоћу индуктивно спрегнуте плазме – оптичке емисионе спектрометрије и наменског живиног анализатора. Антропогени утицај на концентрацију тешких метала у седиментима процењен је израчунавањем различитих индекса загађења: индекса геоакумулације (Igeo),фактора контаминације (Cf), индекса оптерећења загађењем (PLI) и индекса потенцијалног еколошког ризика (Er). Добијени резултати указују да не постоје статистички значајне просторне разлике у концентрацији метала, што указује на то да тешки метали у испитиваним седиментима имају константан извор. Антропогени утицај изражен у вредностима индекса загађења показао је да су локације генерално незагађене кобалтом, хромом и ванадијумом, а умерено загађене цинком, бакром и никлом. С друге стране, кадмијум, жива и олово представљају највећи еколошки ризик. Антропогени извори ових метала су индустрија, комунални отпад и сагоревање фосилних горива. Добијени резултати показују висок еколошки ризик и потребу за мониторингом животне средине, подржавајући развој ефикасне стратегије за смањење локалног загађења и загађења испитиваног подручја.

The fluorescent probe fluorescein hydrazide was designed for mercury sensing by fluorescence assay. The probe was color less and non-fluorescent in the absence of Hg2+ ions and highly fluorescent and green colored in the presence of Hg2+ ions. The probe is highly specific to Hg2+ ions under pH 12 buffer conditions. No other ions interfered during fuolrimetric analysis of the Hg2+ ions. The fluorescence assay was done at excitation wavelength of 502 nm and emission wavelength at 520 nm. The emission wavelength measured at 520 nm is proportional to the concentration of Hg2+ ions in the assay solution. The developed fluorescence assay protocol based on fluorescein hydrazide as fluorescent probe was used for mercury speciation in lead acid battery samples successfully.

An ecofriendly microwave pyrolysis tactic was employed to synthesize N-doped fluorescent carbon nanodots (N-CNDs) using Gum ghatti and ethylenediamine as a carbon and nitrogen source. The fabricated N-CNDs exhibits high stability in water medium and emits bright blue fluorescence with the quantum yield of 23%. We further established N-CNDs as an excellent visual and selective fluorescent-based nanoprobe for mercury ions (Hg2+ ions) detection. The limit of detection was found to be 4.6 nM. When metal ion chelator ethylenediaminetetraacetic acid (EDTA) was added into the N-CNDs + Hg2+ ions system, the fluorescence was reverted effectively. Moreover, the fluorescent quenching principle of N-CNDs + Hg2+ ions system follows the static quenching mechanism. Finally, the Gum ghatti derived N-CNDs was efficiently applied in environmental water samples like tap and mineral water to determine mercury ions.

As the heaviest group 12 element known now, copernicium (Cn) often presents the oxidation states of +I, +II, and rarely +IV as in its homologue mercury. In this work we systematically studied the stability of some oxides, fluorides, and oxyfluorides of Cn by two-component relativistic calculations, and found that the CnF6 molecule with an oxidation state of +VI has an extraordinary stability. CnF6 may decompose into CnF4 by conquering an energy barrier of about 30 kcal/mol without markedly releasing heat. Our results indicates that CnF6 may exist under some special conditions.

Autism is a severe developmental disease characterized by social disengagement, communication impairments, and repetitive/stereotypic behaviour. Although the pathophysiological etiologies of autism remain obscure and contentious in many cases, genetic and environmental variables (and their interactions) have been identified. While autism is recognized to have multiple causative reasons, ecological variables have gained considerable attention. The Global debate has centred on neurotoxins such as Mercury, Cobalt, and Aluminium, with some claiming that these and other toxic metals contribute to the disorder's development. The study is performed in Al-Anbar province (Iraq) between march to December 2020. Seventy-five autistic patients suffered from ASD characterized by DSM-V compared with twenty-five control. Heavy metals and trace element Mercury, aluminum, and cobalt in hair specimens are measured by atomic absorption spectrophotometer are shown as higher in Aluminium concentration in patients versus healthy Control, and Global Value, more than Aluminium contributed as environmental risk-factor for ASD, While the level of Cobalt is described high in children with autistic and slightly in healthy Control compare with Global Value. These results come from environmental contaminated in Iraq's. Additively, Mercury concentration is significantly higher in autistic patients than in Control. Still, the concentration of both autism and Control typical compared with Global Value and Mercury consider no-environmental risk-factor for Iraqi community’s.

Mercury, Hg, is one of the most problematic metals from an environmental perspective. To assess the problems caused by Hg in the environment it is crucial to understand the processes of Hg biogeochemistry, but the exchange of Hg between the atmosphere and vegetation is not sufficiently well characterised. We explored the mercury concentration, [Hg], in foliage from a diverse set of plant types, locations and sampling periods to study whether there is a continuous accumulation of Hg in leaves/needles over time. Measurements of [Hg] were made in deciduous and conifer trees in Gothenburg, Sweden (Botanical Garden and city area) as well as of evergreen trees in Rwanda. In addition, data for wheat from an ozone experiment conducted at Östad, Sweden, were included. Conifer data were quantitatively compared with literature data. In every case where older foliage was directly compared with younger, [Hg] was higher in older tissue. Covering the range of current year up to four-year old needles, there was no sign of Hg saturation in conifer needles with age. Thus, over time scales of approximately one month to several years, the Hg uptake in foliage from the atmosphere always dominated over Hg evasion. Rwandan broadleaved trees had generally older leaves due to lack of seasonal abscission and higher [Hg] than Swedish broadleaved trees. The significance of atmospheric Hg uptake in plants was shown in a wheat experiment where charcoal filtrated air lead to significantly lower leaf [Hg]. To search for general patterns, the accumulation rates of Hg in the diverse set of tree species in the Gothenburg area were related to the specific leaf area (SLA). Leaf area based [Hg] was strongly negatively and non-linearly correlated with SLA, while mass-based [Hg] had a somewhat weaker positive relationship with SLA (both relationships with p < 0.001). An elaborated understanding of the relationship behind [Hg] and SLA would support large-scale modelling of Hg uptake by vegetation and Hg circulation in general.

Metallomacrocycles that include several metal ions with the Lewis acid properties are peculiar antipodes of crown ethers (referred to as ‘anticrowns’ in the literature). Recently these architectures have been extensively investigated when searching for efficient and selective anion receptors. In this review, we analyze the data on the molecular and crystal structures of supramolecular complexes of mercury-containing macrocycles (hosts) with anions or neutral nucleophiles (guests). The emphasis is on the identification and systematization of the structure types of complexes in dependence of the guest molecule nature, as well as the macrocycle composition and structure. The factors affecting the selectivity of coordination and competitive ability of various electron donor moieties of guest molecules to binding to the macrocycle are considered. The data in the literature on the nonvalent host – guest and host – host interactions, which are responsible for the formation of molecular complexes and their supramolecular association in crystals, are analyzed. The formulated structural regularities of these coordination compounds with an unusual type of molecular architecture open ways to design directly promising molecular materials on their basis. The bibliography includes 161 references.

Rice husk, as an abundant agricultural waste and renewable biomass, is adopted to produce porous silica which is used as a potential carbon-free adsorbent for mercury emission control of coal-fired power plants. The rice husk derived porous silica (RHS) exhibits a good Hg0 adsorption capability with Hg0 removal efficiency above 80% in the temperature range of 60–140 °C, which is plausibly due to the big specific surface area and mesoporous structure. The mercury removal performance of RHS can be evidently reinforced by KBr modification. The optimal KBr loading value and reaction temperature are 2 wt% and 140 °C, respectively. Acidic gas components, such as NO and SO2, both show slight inhibitive effects on Hg0 adsorption process probably owing to the competitive adsorption or the elimination of adsorption sites.

A synthetic method is described to produce some chromenone-pyrazole derivatives through a one-pot multicomponent reaction using SrFe12O19 as a magnetic catalyst. This method provides quite a few merits, including the use of an effective and easy separable nanocatalyst, high yields of products, short reaction time, and easy work-up. Two of the products showed fluorescence properties, which have detected mercury ions without any interference with other ions. They can detect a tiny amount of mercury ions, which were comparable with other chemosensors. The detection limit is 4 × 10-7 and 3 × 10-8 M, respectively, for the compound I and II, respectively, which were considered very low amounts. The effect of mercury on health and environmental pollution is essential in medical science.

Around population, worldwide 10% are affected by chronic kidney disease (CKD). Hemodialysis is the common choice of renal replacement therapy. Cigarette smokers has high lead level than non-smoker populalion.as Tobacco leaf grown on polluted soil. Mercury poisoning depend on dose and duration of exposure. Aim of the study is to determine two important toxic heavy metals elements lead and mercury concentrations in pre hemodialysis blood sample of CKD patients on maintenance hemodialysis for more than 6 months divided into non-smoker and smoker with exclusion of cases with occupational exposures by comparison with control group non-CKD, non-smoker persons. Our study is conducted in September 2019 in Al Mokattam insurance hospital in Cairo this study involved 60 persons are divided into 3 groups both sex with no racial exclusion criteria: CKD stage 5 patients on hemodialysis 40 patients divided into 2 groups (smoker) 20 patients and (non-smoker) 20 patients with history of eating fish and seafood are taken by comparison with healthy control group. Lead and mercury are analyzed by electro thermal atomic absorption spectrophotometer in Al Borg central Lab. Our study proves that prolonged duration on hemodialysis not raise lead and mercury level in blood, smoking raises lead level in blood, eating fish and sea food more than once per week lead to increase mercury level in blood, there is relation between raised lead level and anemia in hemodialysis patients.

In recent years, special attention has been given to emission research that led to the deposition of toxicants from road traffic. Thus, it is imperative to focus on heavy metal (HM) stressors in food items, their source contribution, and health risk assessment providing insight into their spatial role at the population level. In this study, heavy metal in the street vended noodles was studied while correlating the quality of noodle with different environmental origins. The samples were prepared using acid digestion and analysed by flame atomic absorption spectrophotometer, except Hg which was analysed by direct mercury analyser. The results showed that some heavy metals like Cr, Pb, Mn, Cd, and Hg exceed their permissible limits established by the international legislation for food products. In the noodle samples, the concentration of heavy metal ranged from

Olfactory sensory neurons (OSNs) of fish belong to three main types: ciliated olfactory sensory neurons (cOSNs), microvillous olfactory sensory neurons (mOSNs), and crypt cells. Mercury is a toxic metal harmful for olfaction. We exposed the olfactory epithelium of zebrafish to three sublethal Hg2+ concentrations. Molecular markers specific for the different types of OSNs were immunohistochemically detected. Image analysis of treated sections enabled counting of marked cells and measurement of staining optical density indicative of the response of OSNs to Hg2+ exposure. The three types of OSNs reacted to mercury in a different way. Image analysis revealed that mOSNs are more susceptible to Hg2+ exposure than cOSNs and crypt cell density decreases. Moreover, while the ratio between sensory/nonsensory epithelium areas is unchanged, epithelium thickness drops, and dividing cells increase in the basal layer of the olfactory epithelium. Cell death but also reduction of apical processes and marker expression could account for changes in OSN immunostaining. Also, the differential results between dorsal and ventral halves of the olfactory rosette could derive from different water flows inside the olfactory chamber or different subpopulations in OSNs.

Mercury (Hg) is a great concern for marine environments. Bird feathers have been widely used to assess Hg pollution. In this study, we determine mercury concentrations in body feathers of juvenile Magellanic penguins (Spheniscus magellanicus) from the southeastern sector of Buenos Aires province, Argentina, during a non-breeding season, considering both sexes. Hg levels, considering both females and males together, ranged between 265.5 and 1515.52 ng/g. These levels are well below the concentrations in feathers suggested for taking actions focused on the protection of seabirds. Non-significant differences between sexes regarding Hg levels were found, probably because juveniles were sexually immature and females did not excrete Hg by egg laying yet. Hg concentrations found in this study were an order of magnitude higher than those reported 10 years ago for the species in breeding areas on the Argentine coast. Thus, the present study provides relevant information indicating a possible increase of Hg pollution in the southwestern region of the Atlantic Ocean and thus trigger for the development of monitoring programs and regional strategies to improve the conservation status of this species.

The concentration of meHg in freshwater fish and seafood was investigated, as well as the consumption patterns of fish and seafood by different demographic groups (age, ethnicity, gender). A potential alarm for human health hazards was also assessed, and the results were compared to the provisional tolerable weekly intakes (PTWIs) and the hazard quotient parameter (HQ). The results showed that meHg levels of 67 species ranged from 0.013 to 0.252 mg/kg of wet weight (WW) with significant differences between different fish and seafood groups (χ2KW = 49.09; p pelagic fish (0.0686 mg/kg WW) > freshwater fish 0.045 mg/kg WW) > cephalopods (0.0405 mg/kg WW) crustaceans (0.0356 mg/kg WW). The results revealed that older population (> 40 years old) consumed significantly (p = 0.000) more fish compared to younger generations and the elderly consumed the highest amounts of fish (104.0 ± 113.0 g/day). The adolescents (10–17 years old) consumed more than double of amount for both cephalopod and crustacean compared to the older populations (p p = 0.000) higher amounts of fish and seafood compared to other ethnicities, similar to male subjects (95.2 ± 102 g/day; p = 0.026) when compared to the female (86 ± 96.3 g/day). The estimated weekly intake (EWI) values showed results below 1.6 µg/kg BW/week, the tolerable levels recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) for all different demographic factors except for higher consumers at 75th percentile and above. Consumption of marine fish contributed to a higher value of PTWI to all different demographic groups (the estimated weekly intake (EWI) range: 0.2988–0.6893 µg/kg BW/week) but for the adolescents, where from the consumption of crustaceans (0.3488 µg/kg BW/week or 21.8% of PTWI) and cephalopods (0.504 µg/kg BW/week or 31.5% of PTWI). The results from this study also revealed the HQ value for overall consumption of fish and seafood by the adolescents and elderly exceeded one. This was contributed from the consumption of demersal fish and cephalopods, thus indicating the nonacceptable level of noncarcinogenic adverse health effects.

Owing to the massive mercury emission from coal-fired power plants and other nonpower industries worldwide, it is imperative to develop non-carbon-based adsorbents for mercury removal. In this work...

Oceans play a key role in the global mercury (Hg) cycle, but studies on Hg isotopes in seawater are rare due to the extremely low Hg concentration and the lack of a good preconcentration method. Here, we introduce a new coprecipitation method for separating and preconcentrating Hg from seawater for accurate isotope measurement. The coprecipitation was achieved by sequential addition of 0.5 mL of 0.5 M CuSO4, 1 mL of 0.5 M Na2S, and 1 mL of 0.5 M CuSO4 reagents, which allowed for quantitatively precipitating Hg from up to 10 L of seawater. The protocol was validated by testing synthetic solutions with varying Hg and iodide (I-) concentrations and by comparing the reaction times of various reagents added. The method resulted in a quantitative recovery of 98 ± 12% (n = 32, two standard deviations, 2 SD) and a relatively low procedure blank (103 pg of Hg, n = 8). The precipitates were filtrated and analyzed for Hg isotopes. Repeated measurements of synthetic seawaters spiked with certificated standard materials (NIST 3133 and 3177) using the entire method gave identical Hg isotope ratios with near-quantitative Hg recovery, indicating no isotope fractionation during preconcentration. A total of six nearshore seawater samples from the Yellow Sea and the Bohai Sea (China) were analyzed using the coprecipitation method. The data showed a large fractionation of Hg isotopes and revealed the possible impact of both atmospheric and anthropogenic inputs to the coastal seawater Hg budget, implying the potential application of this method in studying marine Hg systematics and global Hg cycling.

The paper deals with the spectral characteristics of the radiation of a pulsed discharge into a cesium – mercury – xenon mixture during the formation of a plasma channel from the moment of ignition until reaching the nominal operating mode of the flash lamp. It is shown that as the electric power of the discharge increases, the spectral emission lines of mercury vapors change their intensity, and the cesium lines self-reversal. It is revealed that the intensity of spectral lines in different regions of the plasma channel differs due to the presence of longitudinal temperature gradients.

A cross-sectional survey of 425 male artisanal and small-scale goldminers (ASGM) was conducted to examine the relationship between the occupational activities of the miners and their blood mercury levels while controlling for relevant biosocial and socio-cultural factors. The data was subjected to descriptive and inferential statistics. Initial findings showed that 43.29% of the ASGM miners had blood mercury levels above the occupational exposure threshold. Among the occupational factors, ASGM miners who amalgamate gold, burn amalgam, and ASGM miners who smelt gold were 2.260, 1.881, and 2.094 times respectively more likely to have high blood mercury levels as compared to ASGM miners who did not carry out these activities. Also, ASGM miners who suck excess mercury with their mouth (OR = 0.197, p

An assessment is made of published data on concentrations of four toxic trace elements arsenic (As), cadmium (Cd), lead (Pb), mercury (Hg), and methyl mercury (MeHg) in seafood species from Algerian coastal waters. The data relate mainly to fish and mollusks, with Pb and Cd being the most studied elements. In contrast, no studies were found for As and MeHg in mollusks and crustaceans, and none for total Hg in crustaceans. Data analysis has shown that the element concentrations depend on the element analyzed, in particular its chemical form, and they vary with the species studied and the area where the organisms were sampled. As concentrations in muscle of sardine (Sardina pilchardus) from the eastern zone (Bejaia) (2.98 mg kg−1 wet weight), Pb in muscle of tuna (Euthynnus alletteratus) (0.49 mg kg−1 wet weight) from the western region (Mostaganem) and in muscle tissue of the mussel (Mytilus galloprovincialis) (10.67 mg kg−1 dry weight) from Oran all exceed the threshold risk limits set by national and international regulations. Given these findings, to guarantee seafood safety for the Algerian consumer, it is recommended to carry out monitoring of these trace elements in seafood species caught along the Algerian coast, particularly the most consumed fish, i.e., sardines, and predators such as swordfish and tuna which can accumulate high concentrations of toxic metals, particularly Hg. Obtaining a regional assessment based on similar analyses from Tunisia and Morocco was severely hampered since few similar species or taxonomic groups were analyzed in all three countries.

The public and environmental health consequences of mercury (Hg) methylation have drawn much attention and considerable research to Hg methylation processes and their dynamics in diverse environmen...

The chemical contaminants in dried fish are of great food safety concern and an emerging public health issue in Bangladesh. The aim of this study was to assess the public health risk associated with exposure to pesticides (organochlorine and organophosphorus) and heavy metals (lead, mercury, cadmium, chromium, arsenic) through the consumption of dried fish (Bombay duck, ribbon fish, silver jewfish, shrimp, Chinese promfret) in coastal districts (Cox’s Bazar, Chittagong, Bhola, Patuakhali, Khulna) of Bangladesh. Dried fish consumption data were collected from 500 adult respondents (100 from each district) using a food frequency questionnaire (FFQ). Pesticide residues were determined using QuEChERS extraction coupled to gas chromatography and gas chromatography mass spectrometry, and heavy metals were estimated using an atomic absorption spectrophotometric method. The results revealed that the frequency and amount of dried fish consumption was highest for Bombay duck in Cox’s Bazar (11.57 g/capita/day) and ribbon fish (12.10 g/capita/day) in Chittagong. The estimated daily intake (EDI, 7.40 × 10−5 to 1.10 × 10−4 mg/kg/day) and health risk index (HRI, 0.013 to 0.16) values expressed no health risk from pesticide residues in all the positive samples. For heavy metals, target hazard quotients (THQ) for non-carcinogenic health risk were below 1 (0.001–0.154), indicating no health risk for all samples. However, carcinogenic risk R value indicated a potential health risk for chromium (2.64 × 10−6 to 4.06 × 10−6), and carcinogenic RT value (2.82 × 10−6 to 5.71 × 10−6) indicated a potential health risk for all the metals. It is concluded that the risk of exposure to pesticides through the consumption of dried fish is low, while heavy metals pose moderate-to-high health risks to dried fish consumers in the study area. Thus, the study suggests an appropriate risk management policy that controls pesticides and heavy metals in dried fish to ensure safe food for local and global consumers, underpinned by a producers’ capacity building and consumers’ awareness raising strategy.