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Bimetallic compounds containing direct metal‐group 13 element bonds have been shown to display unprecedented patterns of cooperative reactivity towards small molecules, which can be influenced by the identity of the group 13 element. In this context, we present here a systematic appraisal of group 13 metallo‐ligands of the type [(NON)E]− (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene) for E=Al, Ga and In, through a comparison of structural and spectroscopic parameters associated with the trans L or X ligands in linear d10 complexes of the types LM{E(NON)} and XM′{E(NON)}. These studies are facilitated by convenient syntheses (from the In(I) precursor, InCp) of the potassium indyl species [{K(NON)In}⋅KCp]n (1) and [(18‐crown‐6)2K2Cp] [(NON)In] (1′), and lead to the first structural characterisation of Ag−In and Hg−E (E=Al, In) covalent bonds. The resulting structural, spectroscopic and quantum chemical probes of Ag/Hg complexes are consistent with markedly stronger σ‐donor capabilities of the aluminyl ligand, [(NON)Al]−, over its gallium and indium counterparts. [ABSTRACT FROM AUTHOR]

Bimetallic compounds containing direct metal‐group 13 element bonds have been shown to display unprecedented patterns of cooperative reactivity towards small molecules, which can be influenced by the identity of the group 13 element. In this context, we present here a systematic appraisal of group 13 metallo‐ligands of the type [(NON)E]− (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene) for E=Al, Ga and In, through a comparison of structural and spectroscopic parameters associated with the trans L or X ligands in linear d10 complexes of the types LM{E(NON)} and XM′{E(NON)}. These studies are facilitated by convenient syntheses (from the In(I) precursor, InCp) of the potassium indyl species [{K(NON)In}⋅KCp]n (1) and [(18‐crown‐6)2K2Cp] [(NON)In] (1′), and lead to the first structural characterisation of Ag−In and Hg−E (E=Al, In) covalent bonds. The resulting structural, spectroscopic and quantum chemical probes of Ag/Hg complexes are consistent with markedly stronger σ‐donor capabilities of the aluminyl ligand, [(NON)Al]−, over its gallium and indium counterparts. [ABSTRACT FROM AUTHOR]

A new ZnII coordination polymer (CP) based on 2,3‐pyrazine dicarboxylic acid (H2pzdc) and 4,4′‐bipyridine (bpy) (ZCP) was synthesized using a facile slow evaporation method. Single‐crystal X‐ray diffraction revealed that ZCP is a two‐dimensional porous CP, [Zn2(pzdc)2(bpy)(H2O)2]n, with van der Waals forces as the dominant interaction within its layers forming a 63 network. Employing energetic ultrasound irradiation, nanoscale ZCP (nZCP) was successfully synthesized and Eu3+ ions were incorporated within its host lattice (Eu@nZCP). The resulting platform exhibits superior fluorescence characteristics and demonstrates notable optical durability. Therefore, it was used as a dual detection fluorescent sensing platform for the detection of mercury and l‐cysteine (l‐Cys) in aqueous media through a turn‐off/on strategy. In the turn‐off process, the fluorescence emission of Eu@nZCP progressively quenches by the addition of HgIIvia a photo‐induced electron transfer (PET) mechanism. The fluorescence of Eu@nZCP is quenched to establish a low fluorescence background through the incorporation of HgII. This devised turn‐on fluorescent system is suitable for the recognition of l‐Cys (based on the strong affinity of l‐Cys to the HgII ion) through a quencher detachment mechanism. This method attained a relatively wide linear range, spanning from 0.001 to 25 µM, with the low detection limit of 5 nM for the sensing of HgII. Also, the corresponding limit of detection (LOD) for l‐Cys is 8 nM in a relatively wide linear range, spanning from 0.001 to 40 µM. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg), an environmental pollutant, is a ubiquitous neurotoxicant that ultimately leads to neurodegenerative diseases. New experimental models are needed for public health toxicity testing associated with this pollutant. In this study, a human pluripotent stem cell‐based brain‐on‐a‐chip, named Communicative Astrocyte–Neuron DYnamics chip (CANDY chip), is reported, which enables observation of the interactions of neurons with astrocytes and accurate assessment of responses to penetration of MeHg across the blood‐brain barrier. Five neurophysiological characteristics of the CANDY chip provide an exact emulation of the brain: i) co‐culture of neurons with astrocytes, ii) transport of nutrients from blood vessels to neurons via astrocytes, iii) glia‐to‐neurons ratio of 1:1, iv) low‐speed flow of brain interstitial fluid, and v) neuroprotection by astrocytes against MeHg‐induced toxicity. The remarkable vulnerability of neurons is identified to MeHg toxicity as shattered neurites and verifies the tolerance of astrocytes to MeHg toxicity despite morphological changes such as cell shrinkage. It is also confirmed that the chip faithfully recapitulates actual neurophysiological responses through high neuronal cell viability because of the astrocytes and increased brain‐derived neurotrophic factor as a neuroprotector. The CANDY chip can be a powerful platform for accurate neurotoxicity testing and modeling of complex neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Pore‐throat structure is a key factor that influences the storage and fluid flow capacity of tight sandstone reservoirs. Taking the tight sandstone reservoir of Xu2 Fm in Zhongba area as an example, the reservoir quality, pore‐throat type and pore size distribution of tight sandstone in the study area were described by casting thin section, scanning electron microscope and high‐pressure mercury injection test. In order to quantitatively characterize the complexity and heterogeneity of pore‐throat structure, fractal analysis was performed using mercury saturation and pore size data. This study mainly reveals the relationship between the geometric shape characteristics and fractal dimension of the binary pore structure of ultra‐low permeability tight sandstone and clarifies the influence of different scale pore throats on reservoir physical properties. The results indicate that the physical properties of the reservoir in the study area are poor, the pores are mainly intergranular pores and dissolution pores, the throat is flake and necked and the pore size distribution range is large. The fractal curve obtained by the mercury saturation method shows a significant turning point, and the pore‐throat system is divided into two types: small‐scale and large‐scale. The fractal dimension of large‐scale pore throat is greater than the three‐dimensional Euclidean space dimension, which does not conform to the fractal theory. The fractal dimension of small‐scale pore throat is closely related to the pore‐throat structure and has obvious fractal characteristics. The geometric shape of binary pore‐throat structure in tight sandstone is the main factor affecting the difference of fractal dimension. The development of small pores in sandstone is positively correlated with the total porosity, but its contribution to permeability is relatively low. The physical properties of tight sandstone are mainly controlled by the development degree of large‐scale pore throat. [ABSTRACT FROM AUTHOR]

Birds are used as bioindicators of environmental mercury (Hg) contamination, and toxicity reference values are needed for injury assessments. We conducted a comprehensive review, summarized data from 168 studies, performed a series of Bayesian hierarchical meta‐analyses, and developed new toxicity reference values for the effects of methylmercury (MeHg) on birds using a benchmark dose analysis framework. Lethal and sublethal effects of MeHg on birds were categorized into nine biologically relevant endpoint categories and three age classes. Effective Hg concentrations where there was a 10% reduction (EC10) in the production of juvenile offspring (0.55 µg/g wet wt adult blood‐equivalent Hg concentrations, 80% credible interval: [0.33, 0.85]), histology endpoints (0.49 [0.15, 0.96] and 0.61 [0.09, 2.48]), and biochemical markers (0.77 [<0.25, 2.12] and 0.57 [0.35, 0.92]) were substantially lower than those for survival (2.97 [2.10, 4.73] and 5.24 [3.30, 9.55]) and behavior (6.23 [1.84, >13.42] and 3.11 [2.10, 4.64]) of juveniles and adults, respectively. Within the egg age class, survival was the most sensitive endpoint (EC10 = 2.02 µg/g wet wt adult blood‐equivalent Hg concentrations [1.39, 2.94] or 1.17 µg/g fresh wet wt egg‐equivalent Hg concentrations [0.80, 1.70]). Body morphology was not particularly sensitive to Hg. We developed toxicity reference values using a combined survival and reproduction endpoints category for juveniles, because juveniles were more sensitive to Hg toxicity than eggs or adults. Adult blood‐equivalent Hg concentrations (µg/g wet wt) and egg‐equivalent Hg concentrations (µg/g fresh wet wt) caused low injury to birds (EC1) at 0.09 [0.04, 0.17] and 0.04 [0.01, 0.08], moderate injury (EC5) at 0.6 [0.37, 0.84] and 0.3 [0.17, 0.44], high injury (EC10) at 1.3 [0.94, 1.89] and 0.7 [0.49, 1.02], and severe injury (EC20) at 3.2 [2.24, 4.78] and 1.8 [1.28, 2.79], respectively. Maternal dietary Hg (µg/g dry wt) caused low injury to juveniles at 0.16 [0.05, 0.38], moderate injury at 0.6 [0.29, 1.03], high injury at 1.1 [0.63, 1.87], and severe injury at 2.4 [1.42, 4.13]. We found few substantial differences in Hg toxicity among avian taxonomic orders, including for controlled laboratory studies that injected Hg into eggs. Our results can be used to quantify injury to birds caused by Hg pollution. Environ Toxicol Chem 2024;43:1195–1241. Published 2024. This article is a U.S. Government work and is in the public domain in the USA. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Geothermal fields emit remarkable amounts of mercury (Hg) to the environment. To address the source, fate and geochemical cycling of Hg in geothermal fields, we investigated Hg concentrations and isotopic compositions of hot spring water and fumarole gases from Rehai and Dagejia in SW‐China. Elevated Hg concentrations in fumarole gases (10.0–167 ng m−3) and hot spring water (3.44–84.5 ng L−1) were observed, suggesting that both geothermal fields are of environmental concern. The variation in Δ199Hg (−0.06 to 0.23‰) and Δ200Hg (−0.09 to 0.19‰) in hot spring water supports Hg likely originating from endogenous volcanic degassing and/or rainwater. Negative and nearly zero Δ199Hg in fumarole gases (−0.32 to 0.03‰) supports volcanic degassing and background atmosphere origin. The ranges of δ202Hg in fumarole gases (−0.74 to 0.59‰) and hot spring water (−1.29 to 0.52‰) could reflect limited fluids boiling in geothermal fields. This study, thus, fills an important knowledge gap regarding Hg global cycling. Plain Language Summary: A large amount of mercury (Hg) is emitted into the atmosphere through geothermal activities. A knowledge gap exists regarding the source, fate and geochemical cycling of Hg in geothermal fields. Here, we studied Hg concentrations and isotopic compositions in hot spring water and fumarole gases from two large geothermal fields in SW‐China. Our results support that the two fields received Hg from endogenous volcanic degassing and rainwater. Deep magma chambers acted as heat sources, triggering fluid circulation in geothermal areas and entraining Hg from rainwater into geothermal systems. Key Points: Rehai and Dagejia geothermal fields are likely of local environmental concern regarding Hg emissionMercury isotopic ratios evidence that geothermal fields could receive Hg from endogenous volcanic degassing and rainwaterGeothermal fluid boiling is not common in geothermal fields in SW‐China [ABSTRACT FROM AUTHOR]

Sulfur polymers, prepared by inverse vulcanization using elemental sulfur and vinylic monomers, are emerging functional materials of current research interest; however, sulfur polymers suffer from limited water solubility due to the hydrophobic nature of conventional comonomers and sulfur. Herein, the preparation of ionic liquid (IL)‐containing sulfur polymers are reported using the hydrophilic ionic liquid, 1‐allyl‐3‐vinylimidazolium chloride (AVImCl) as a comonomer. The introduction of IL significantly enhances the hydrophilicity of sulfur polymers, enabling them to dissolve in water. Benefiting from the thorough contact with aqueous mercury ions, the resultant sulfur polymer possesses high uptake capacity (436 mg g−1). After binding mercury, a coordination complex is formed and precipitated. The charged sulfur polymers gain a new application in demulsification. The polymer quickly breaks oil‐in‐water (O/W) emulsions through anion exchange between Cl− of the polymer and dodecylbenzenesulfonate (DBS−) of the surfactant. In addition, the polymer has a growth inhibitory effect against Staphylococcus aureus. The integration of IL and elemental sulfur provides a novel approach to modifying the wettability of sulfur polymers. Also, this novel water‐soluble IL‐containing sulfur polymer, with mercury capture, demulsification, and antibacterial activity, can be considered as a multifunctional material in practical water purification. [ABSTRACT FROM AUTHOR]

A series of Fe6Mn1Cux adsorbents for mercury removal were prepared by using co‐precipitation and impregnation methods. The performance of mercury adsorption and anti‐SO2 characteristic was studied in a fixed‐bed experimental system. The effect of Cu doping amount, reaction temperature, and flue gas components on mercury removal was investigated. The mercury species on the spent adsorbent was analyzed through Hg‐TPD test. The physical–chemical features were characterized by using the N2 adsorption/desorption, VSM, XPS, and XRD. It was found that the Fe6Mn1Cu0.4 exhibited a high performance of mercury adsorption and well magnetic property and good sulfur resistance. Under high concentration of SO2, the average adsorption efficiency of Fe6Mn1Cu0.4 adsorbent achieved 99%. Cu modification optimized the pore structure and improved the mercury removal performance as well as SO2 resistance. The XPS analysis indicated that Mn4+ was the main form that played an important role in oxidizing Hg0, as a result of decrement of Mn4+ after mercury adsorption. Mercury adsorbed on the spent adsorbent was HgO and HgSO4. [ABSTRACT FROM AUTHOR]

This article reviews research on sediment flux impacts on the receiving estuary, ports, and society in Cartagena, Colombia. The city hosts both the country's largest touristic and coastal industrial sectors and is home to vulnerable coastal communities whose health and livelihoods are impacted by pollution. These marginalized artisanal fishing communities lack basic water and health services but have finally been recognized in a new intersectoral committee for Cartagena Bay's environmental management. To support the governance of these complex socioenvironmental challenges, the Cartagena Bay Observatory has been developed as a scientific tool to monitor the bay's conditions and forecast the effects of future sediment remediation plans. Cartagena Bay receives large freshwater discharges from the Dique Canal, draining from the 260,000 km2 Magdalena River watershed where 80% of the national population resides. This runoff transports sediment loads of 2.3 Mt/year, dispersing large plumes that affect the marine ecosystems and tourism and make the bay one of the Caribbean's largest sediment‐receiving estuaries. Following decades of watershed deforestation and erosion, the upward trending sediment inputs and accretion of the Dique delta have resulted in deposition rates of 1.8 cm/year, and the need for frequent dredging. Mercury dumped by a chemical industry in the 1970s can be found in concentrations as high as 18.8 μg/g buried below the bay's bottom. Mercury has also been found in the bay's biota and human populations, and so the dredging needed for the port's sustainability thereby presents a health risk by allowing this trapped mercury to surface. This article is categorized under:Science of Water > Hydrological ProcessesScience of Water > Water QualityScience of Water > Water and Environmental Change [ABSTRACT FROM AUTHOR]

Currently barrens communities only represent about 1% of their original area in the Great Lakes region. To maintain or restore barrens vegetation, prescribed fire is often applied to limit the regeneration of undesirable species and shrubs. Vegetation community response is a combination of direct fire effects on the vegetation vitality and the indirect effect of soil nitrogen (N) loss that favors nutrient‐poor adapted barren communities. In this study, we assessed forest floor and upper mineral soil (0–5 cm) pools of carbon (C), N, and mercury (Hg) before and after prescribed fire of the Moquah Barrens in northwest Wisconsin. Although we took measurements in four distinct cover types, we found no relationship between cover type and soil pools. Across all cover types, prescribed fire led to considerable emissions of C, N, and Hg in the forest floor but only Hg in the upper mineral soils (0–5 cm), presumably because maximum fire temperatures were met for Hg volatilization. We classified fire severity and soil surface temperatures at the quadrat scale, but no discernable relationships with emissions were observed. The lack of detectable relationships is likely the result of a mismatch between the scales of response variables and predictors. As a result, we calculated ecosystem‐scale fire emissions based on the total area burned because we could not discern other smaller scale predictors. Overall emissions from dormant, spring season prescribed fires at the Moquah Barrens were approximately 11,000 Mg (5.5 Mg ha−1) for C, 350 Mg for N (0.17 Mg ha−1), and 4,500 g for Hg (2.3 g ha−1). Core Ideas: Imperiled barrens communities only represent a small area of their original distribution.As a result of the decrease in barrens habitat, associated fauna and flora are also in decline.Prescribed fire is used to maintain or restore barrens ecosystems.Fire leads to the changes in soil carbon, nitrogen, and mercury pools and leads to associated emissions.Emissions from the Moquah Barrens prescribed fires were minor and did lead to the goal of decreasing soil nitrogen. [ABSTRACT FROM AUTHOR]

This paper investigates women's everyday reproductive struggles in contexts of toxic contamination and the tensions emerging between toxic exposure and care in women's experiences of motherhood. While scientific framings of reproductive disruptions understand social identities as pre‐existing the experience of toxic risks, in this paper I argue that, in toxic territories, the categories of “contaminating” and “contaminated” actors interact with other categories of identity, such as gender and race, shaping social relations. Drawing on 13 months of ethnographic fieldwork conducted in the Bajo Cauca region among gold mining and coca farming communities, I investigate the everyday processes of gendered subject formation that unfold in toxic territories and the emergence of “faulty” gendered identities for rural mothers. Building on scholarship in feminist geography and Latin American feminist science and technology studies, I argue that ineffective forms of integration of gender in the institutional debate on toxic contamination reproduce, rather than challenge, the invisibility of rural women before the state. [ABSTRACT FROM AUTHOR]

In this study, the primary objective is to synthesize a novel fluorescent Rh‐PP‐Rh compound and explore its extensive range of photochemical behaviors. Initially, the synthesis of the novel Rh‐PP‐Rh was carried out for this purpose. Subsequently, UV‐Vis and fluorescence spectroscopy were employed to investigate the interactions between Rh‐PP‐Rh and a diverse array of ions in aqueous solvent systems. Through fluorescence and UV‐Vis studies, it was observed that Rh‐PP‐Rh demonstrated turn‐on sensor properties in the presence of Hg2+ ions. Furthermore, the limits of detection (LOD) and association constant (Ka) values for Rh‐PP‐Rh/Hg2+ were determined as 334 nM and 9.13×1011 M−2, respectively. Additionally, the reversible studies demonstrated a switchable on/off response upon alternate addition of HgCl2 and [Bu4N]F to Rh‐PP‐Rh. These findings suggest that the probe Rh‐PP‐Rh also possesses specific sensor properties for F− ions in the presence of mercury. In addition, the investigation encompassed an assessment of the visual analysis of the color alterations of Rh‐PP‐Rh both on filter paper and in an EtOH/H2O solution. The findings demonstrated that Rh‐PP‐Rh can be successfully utilized in solutions containing mercury, as it generates significant color transformations. [ABSTRACT FROM AUTHOR]

The Cambro‐Ordovician interval marks a significant transition from extinction to bio‐diversification in deep time. However, the relationship of bio‐transition to volcanism, commonly characterized by mercury (Hg) systematics in sedimentary records, has not been examined. We present the first Cambro‐Ordovician Hg systematics from the Scandinavian Alum Shale. Our results show pronounced Furongian Hg enrichments, coupled with positive Δ199Hg, Δ200Hg, and Δ201Hg values and negative Δ204Hg values that we ascribe to atmospheric Hg transport over long‐distances, while Early Ordovician Hg anomalies, characterized by near‐zero mass‐independent isotope values, indicative of submarine source. Our findings are supported by two new proxies: molybdenum‐Hg and vanadium‐δ202Hg co‐variations, demonstrating Hg systematics were strongly influenced by changes in source and depositional conditions. Constrained by a synchronous atmospheric‐tectonic‐oceanic model, we hypothesize Furongian subaerial volcanism contributed to global extinction and oceanic anoxia, whereas Early Ordovician submarine volcanism concurrent with ocean water upwelling promoted the nascent bio‐diversification. Plain Language Summary: The late Cambrian‐Early Ordovician interval is a crucial time that bridges the Cambrian extinction and Great Ordovician Bio‐diversification events. The former is associated with 50% decrease in genera, whereas the latter displays threefold increase in species. Volcanism is associated with extinction and bio‐development events throughout Earth's history. Prior works investigated potential biogeochemical controls that could have supported the Cambro‐Ordovician bio‐transition, but none explored the role of volcanism. We, for the first time, examine Hg abundance ratios and isotopes in the Scandinavian Alum Shale core across this boundary. Two novel molybdenum‐Hg and vanadium‐δ202Hg models are proposed to improve our interpretation of the geochemical records about the effects of volcanism on environmental changes during this enigmatic transition. Constrained by a synchronous atmospheric‐oceanic‐tectonic model, our results demonstrate that late Cambrian subaerial volcanism contributed to oceanic anoxia and extinction, whereas Early Ordovician submarine volcanism and water upwelling led to the subsequent bio‐radiation. Key Points: Mercury is associated with organic matter in carbonaceous Alum shale deposited under sulfidic conditionsLate Cambrian‐Early Ordovician mercury was released by volcanism that also triggered major environmental changeMercury mass independent fractionation isotopes suggest late Cambrian subaerial volcanism but Early Ordovician submarine source [ABSTRACT FROM AUTHOR]

The exploration of high-performance mid- and far-infrared (IR) nonlinear optical (NLO) crystals is an urgent need. Herein, a new Hg-based selenide Hg7P2Se12 (HPSe) is designed and synthesized by a rigid and flexible units coupled strategy. It is interesting that in the compound, three types of NLO-active units, including linear [HgSe2], triangular [HgSe3], and tetrahedral (MSe4) (M= Hg/P) groups, simultaneously exist. It shows a wide transparency range (0.84-22.8 µm), large SHG response (1 x AGS), high laser-induced damage threshold (≈ 2 x AGS), and a large birefringence (0.102 @2090 nm). Moreover, the compound melts congruently along with good crystal growth habits, and single crystals with a maximum size of ≈ 7 x 5 x 2 mm³ are obtained. Theoretical analyses confirm that the large NLO response originates from the synergistic effects of Hg-Se units, (PSe4) and nonbonding electrons. The results indicate that HPSe is a promising mid- and far-IR NLO material, and inspire a path to finding new classes of IR NLO materials that are different from traditional chalcopyrite materials by grouping the linear, planar, and tetrahedral units. [ABSTRACT FROM AUTHOR]

Objective: To study the association between maternal exposure to arsenic, cadmium, lead, manganese and mercury, time‐to‐pregnancy (TTP) and infertility. Design: Pregnancy‐based retrospective TTP cohort study. Setting: Hospitals and clinics from ten cities across Canada. Population: A total of 1784 pregnant women. Methods: Concentrations of arsenic, cadmium, lead, manganese and mercury were measured in maternal whole blood during the first trimester of pregnancy as a proxy of preconception exposure. Discrete‐time Cox proportional hazards models generated fecundability odds ratios (FOR) for the association between metals and TTP. Logistic regression generated odds ratios (OR) for the association between metals and infertility. Models were adjusted for maternal age, pre‐pregnancy body mass index, education, income, recruitment site and plasma lipids. Main Outcome Measures: TTP was self‐reported as the number of months of unprotected intercourse to become pregnant. Infertility was defined as TTP longer than 12 months. Results: A total of 1784 women were eligible for the analysis. Mean ± SD maternal age and gestational age at interview were 32.2 ± 5.0 years, and 11.6 ± 1.6 weeks, respectively. Exposure to arsenic, cadmium, manganese or mercury was not associated with TTP or infertility. Increments of one standard deviation of lead concentrations resulted in a shorter TTP (adjusted FOR 1.09, 95% CI 1.02–1.16); however, the association was not linear when exposure was modelled in tertiles. Conclusion: Blood concentrations of metals at typical levels of exposure among Canadian pregnant women were not associated with TTP or infertility. Further studies are needed to assess the role of lead, if any, on TTP. [ABSTRACT FROM AUTHOR]

Bimetallic compounds containing direct metal‐group 13 element bonds have been shown to display unprecedented patterns of cooperative reactivity towards small molecules, which can be influenced by the identity of the group 13 element. In this context, we present here a systematic appraisal of group 13 metallo‐ligands of the type [(NON)E]− (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene) for E=Al, Ga and In, through a comparison of structural and spectroscopic parameters associated with the trans L or X ligands in linear d10 complexes of the types LM{E(NON)} and XM′{E(NON)}. These studies are facilitated by convenient syntheses (from the In(I) precursor, InCp) of the potassium indyl species [{K(NON)In}⋅KCp]n (1) and [(18‐crown‐6)2K2Cp] [(NON)In] (1′), and lead to the first structural characterisation of Ag−In and Hg−E (E=Al, In) covalent bonds. The resulting structural, spectroscopic and quantum chemical probes of Ag/Hg complexes are consistent with markedly stronger σ‐donor capabilities of the aluminyl ligand, [(NON)Al]−, over its gallium and indium counterparts. [ABSTRACT FROM AUTHOR]

An ongoing magnetic reconnection event was detected in the Mercury's high latitude magnetopause during a northward interplanetary magnetic field. The reconnection X‐line region was revealed in the Mercury's magnetopause based on the encountered flux ropes ejected away from this region both planetward and tailward. A series of magnetic flux ropes, known as flux transfer event shower were observed tailward of this X‐line region. These flux ropes were probably expanding and deflected as they were ejected away tailward from the X‐line region. Large‐amplitude variations in all three components of the magnetic field and a few small‐scale flux ropes were observed inside the X‐line region, which could be the seed of the flux rope shower at the magnetopause. The observations suggest that magnetic reconnection is highly dynamic and persistent in Mercury's magnetosphere. Plain Language Summary: Magnetic reconnection has been regarded as the most important process for dynamics of the Mercury's magnetosphere and for the interaction between the solar wind and the Mercury's magnetosphere also. Although magnetic flux ropes and flux transfer events (FTEs) resulting from magnetic reconnection have been extensively observed in the Mercury's magnetosphere, the key region of magnetic reconnection, namely the X‐line region, has never been reported so far by the spacecraft. Here, we present the first evidence of the reconnection X‐line region in the Mercury's magnetosphere. A few small‐scale magnetic flux ropes are observed inside the reconnection X‐line region, which could be the seed of the observed magnetic FTE shower. Furthermore, the evolution of these flux ropes is addressed also based on the spacecraft observations. Key Points: A reconnection X‐line region is first observed in the Mercury's magnetopause during the northward interplanetary magnetic fieldThe small‐scale magnetic flux ropes in the X‐line region could be the seed of the flux transfer event showerThe flux ropes probably expand and is deflected after they are ejected away from the X‐line region [ABSTRACT FROM AUTHOR]

A water‐soluble polymeric pyrene‐based polythioacetal (PTA‐Py) with thioacetal units in the main chain is simply synthesized by direct polycondensation of 3, 6‐dioxa‐1, 8‐octanedithiol, 1‐pyrene formaldehyde, and mPEG2k‐SH. The probe PTA‐Py shows a good fluorescence response to Hg2+ ions due to the Hg2+‐promoted deprotection reaction of thioacetal groups to regenerate the original 1‐pyrene formaldehyde compound. After adding Hg2+ to the PTA‐Py solution, the fluorescence intensity (FI) gradually increases with increasing concentrations of Hg2+. Compared with other metal ions, the probe exhibits high sensitivity, good selectivity, and rapid response to Hg2+. The low detection limits are 12.3 nm in ethanol‐PBS buffer and 13.3 nm in water, respectively. The results imply that the simply synthesized water‐soluble polymeric probe had potential applications in the rapid detection of Hg2+ ions in aqueous solutions. Moreover, the polymeric PTA‐Py shows high sensitivity for CH3Hg+ with detection limits of 26.5 nm in ethanol/PBS buffer. In addition, PTA‐Py can efficiently detect Hg2+ ions in HeLa cells. The results demonstrate that a valuable method is developed for biocompatible polymeric sensors for Hg2+ ions in biological and environmental samples. [ABSTRACT FROM AUTHOR]

Ten mixed‐ligand phenyl mercury(II) complexes containing 1‐methyl‐1H‐tetrazole‐5‐thiol (HmtzS) (1) and phosphine or amine ligands. These complexes fall into two groups: [PhHg(mtzS){Ph2P(CH2)PPh2}]2 (2) and [PhHg(mtzS){Ph2P(CH2)nPPh2}] (3‐6), where n varies, and [PhHg(mtzS)(diamine)] (8‐10), with diamine choices being 2,2′‐bipyridyl (Bipy, 8), 1,10‐phenathroline (Phen, 9), or ethylenediamine (en, 10). These complexes were synthesized with moderate to high yields and characterized using various techniques. Characterization data revealed that the mtzS− ligand coordinates as a monodentate ligand through the thiolate sulfur atom in all complexes, adopting a tetrahedral geometry around the Hg(II) center. Furthermore, complexes [PhHg(mtzS)] (1) and its diamine derivatives (8‐10) were assessed for hydrogen storage at 77 K using the VTI method. Results demonstrated that the incorporation of diamines improves hydrogen storage capacity at low pressure. The precursor stored (1) 2.3 wt.% at 80 bar, while the other complexes showed storage capacities ranging from 2.9 to 3.86 wt.% at pressures of 45‐60 bar. Thermodynamic properties of the [PhHg(mtzS)(Bipy)] complex was calculated at three different temperatures. The results prove that the entropy was equal to 0.50543599 J/mol H2. K while the enthalpy equal to 0.0942638 KJ/(mol H2). [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a global pollutant whose atmospheric deposition is a major input to the terrestrial and oceanic ecosystems. Gas‐particle partitioning (GPP) of gaseous oxidized mercury (GOM) redistributes speciated Hg between gas and particulate phase and can subsequently alter Hg deposition flux. Most 3‐dimensional chemical transport models either neglected the Hg GPP process or parameterized it with measurement data limited in time and space. In this study, CMAQ‐newHg‐Br (Ye et al., 2018, https://doi.org/10.1002/2017ms001161) was updated to CMAQ‐newHg‐Br v2 by implementing a new GPP scheme and the most up‐to‐date Hg redox chemistry and was run for the northeastern United States over January‐November 2010. CMAQ‐newHg‐Br v2 reproduced the measured spatiotemporal distributions of gaseous elemental mercury (GEM) and particulate bound mercury (PBM) concentrations and Hg wet deposition flux within reasonable ranges and simulated dry deposition flux in agreement with previous studies. The GPP scheme improved the simulation of PBM via increasing winter‐, spring‐ and fall‐time PBM concentrations by threefold. It also improved simulated Hg wet deposition flux with an increase of 2.1 ± 0.7 μgm2 in the 11‐month accumulated amount, offsetting half of the decreasing effect of the updated chemistry (−4.2 ± 1.8 μgm2). Further, the GPP scheme captured the observed Kp‐T relationship as reported in previous studies without using measurement data and showed advantages at night and in rural/remote areas where existing empirical parameterizations failed. Our study demonstrated CMAQ‐newHg‐Br v2 a promising assessment tool to quantify impacts of climate change and emission reduction policy on Hg cycling. Plain Language Summary: Mercury is a toxic global pollutant and can enter the food chain through atmospheric deposition to ecosystems. Atmospheric mercury was defined operationally in the forms of gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate bound mercury (PBM). GEM is relatively inert, but GOM and PBM are highly soluble and readily removed from the air via deposition. GEM gets oxidized to GOM and GOM can be transformed to PBM through gas particle partitioning (GPP). CMAQ‐newHg‐Br v2 was updated from its predecessor via implementing the most up‐to‐date Hg redox chemistry and a new GPP scheme. The model improved the simulation of GEM, PBM, and Hg wet deposition. Most notably the model reproduced the observed partitioning coefficient and temperature relationship (Kp‐T) and improved nighttime and less polluted PBM simulations. CMAQ‐newHg‐Br v2 can be used to assess how climate change and emission reduction policy impact environmental Hg cycling. Key Points: CMAQ‐newHg‐Br was updated to version 2 with a new gas‐particle partitioning (GPP) scheme and the most up‐to‐date Hg redox chemistryCMAQ‐newHg‐Br v2 better simulated gaseous elemental mercury (GEM), particulate bound mercury (PBM) and Hg wet depositionThe new GPP scheme captured the observed Kp‐T relation not using measurement data and improved nighttime and less polluted simulations [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD) is characterized by repetitive behaviors and deficits in social interaction. Its etiology is not completely clear, but both genetic and environmental factors contribute to and influence its development and course. The increased number of autism cases in recent years has been strongly associated with increased exposure to heavy metals. Mercury (Hg) has gained prominence in the scientific literature as a result of its presence as an urban pollutant and well‐described neurotoxicity. This review assessed the relationship between Hg exposure in the pre‐ and post‐natal period and ASD. The systematic review identified observational clinical studies and pre‐clinical trials in journals indexed in the PubMed, Embase, ProQuest, and LILACS databases. The aim of this study was to investigate the association between exposure to Hg and ASD and to define the critical period of exposure. A total of 57 articles were selected for this review, with 35 articles (61.40%) identifying a positive association between ASD and Hg, while 22 articles (38.60%) did not find the same outcome. The biological samples most used to analyze Hg body burdens were hair (36.84%) and blood (36.84%). Most case–control studies found an increase in Hg levels in individuals with ASD who were exposed to a polluted environment in the post‐natal period. Taken together, the studies suggest that these patients have a deficient detoxification system, and this could worsen the symptoms of the disorder. However, new studies addressing the influence of Hg on the post‐natal nervous system and its relationship with ASD should be carried out. [ABSTRACT FROM AUTHOR]

The Late Permian was marked by a series of important geological events and widespread organic‐rich black shale depositions, acting as important unconventional hydrocarbon source rocks. However, the mechanism of organic matter (OM) enrichment throughout this period is still controversial. Based on geochemical data, the marine redox conditions, paleogeographic and hydrographic environment, primary productivity, volcanism, and terrigenous input during the Late Permian in the Lower Yangtze region have been studied from the Putaoling section, Chaohu, to provide new insights into OM accumulation. Five Phases are distinguished based on the TOC and environmental variations. In Phase I, anoxic conditions driven by water restriction enhanced OM preservation. In Phase II, euxinic and cycling hydrological environments were the two most substantial controlling factors for the massive OM deposition. During Phase III, intensified terrestrial input potentially diluted the OM in sediment and the presence of oxygen in bottom water weakened the preservation condition. Phase IV was characterized by a relatively higher abundance of mercury (Hg) and TOC (peak at 16.98 wt%), indicating that enhanced volcanism potentially stimulated higher productivity and a euxinic environment. In Phase V, extremely lean OM was preserved as a result of terrestrial dilutions and decreasing primary productivity. Phases I, II and IV are characterized as the most prominent OM‐rich zones due to the effective interactions of the controlling factors, namely paleogeographic, hydrographic environment, volcanism, and redox conditions. [ABSTRACT FROM AUTHOR]

Geological maps of Earth typically incorporate field observations of rock lithology, structure, composition, and more. In contrast, conventional planetary geological maps are often made using primarily qualitative morphostratigraphic remote sensing observations of planetary surfaces. However, it is possible to define independent quantitative spectral units (SUs) of planetary surfaces, which potentially contain information about surface composition, grain size, and space weathering exposure. Here, we demonstrate a generic method to combine independently derived geomorphic and SUs, using the Rachmaninoff basin, Mercury, as an example to create a new geostratigraphic map. From this geostratigraphic map, we can infer some compositional differences within geomorphic units, which clarifies and elaborates on the geological evolution of the region. Plain Language Summary: Geological maps of rocks on Earth include information about what landforms the rocks exhibit, what they are made from, their orientation, and more. Many such details require ground observations, but these are generally not available for planetary geological maps, which rely on spacecraft data. Spacecraft images can be used to map planetary surface textures (geomorphology), but they can also be used to measure surfaces' responses to light (reflectance or emission spectra), which contain information about what the surface rocks are made from, their physical properties (e.g., grain size, roughness, porosity), and how long they have been exposed at the surface. We have combined earlier, independent geomorphic and spectral maps of the Rachmaninoff impact basin on Mercury to create a new "geostratigraphic" map that is more like a geological map that could be made of Earth. The new map highlights places that in the original geomorphic map would have been mapped all as a single unit, but are divisible based on spectral variations, attributable to differences in what the rocks are made from. This allows us to reconstruct a more detailed geological history of the region. Our method can be applied to other regions on Mercury and to other planetary surfaces. Key Points: We combine independent morphostratigraphic and spectral units of Rachmaninoff basin to create geostratigraphic unitsGeostratigraphic units can distinguish volcanic plains and impact melt in contact with each otherGeostratigraphic units imply a wider distribution of (LRM‐composition) impact melt than previously recognized [ABSTRACT FROM AUTHOR]

Mercury (Hg) contamination in the environment is a persistent issue as emissions from industry are ongoing and legacy cycling is prolonged. To quantify total mercury (total Hg) and methylmercury (MeHg) concentrations in lake sediments across a wide suite of temperate to subarctic lakes, measurements and modeling were conducted for 320 sites across Canada. Total Hg varied from 7 to 567 ng g−1 dry sediment with a mean (median) value of 148 (128) ng g−1 dry sediment, with lowest concentrations observed in eutrophic lakes of the Prairies and Boreal Plains. Average total Hg concentrations have increased twofold in contemporary sediments relative to their preindustrial pair. MeHg concentrations were generally low, with a mean of 0.8 ng g−1 dry sediment and this form representing on average 0.6% of the total contemporary mercury concentrations. Water column variables related to eutrophication were among the strongest predictors of contemporary total Hg, MeHg, and total Hg enrichment in the sediments. In lakes where sediment radiometric data were collected, contemporary total Hg accumulation rates were strongly related to longitude(+) and Hg atmospheric deposition(+). Latitude(−) and Hg atmospheric deposition(+) were the best predictors of MeHg accumulation rates. Chromophoric dissolved organic matter optical properties were key predictors of both total Hg concentrations and accumulation rates. Our work highlights the paramount importance of lake trophic state and the nature of organic matter as key predictors of lake sediment mercury metrics. [ABSTRACT FROM AUTHOR]

The mid‐Proterozoic (∼1.8–0.8 Ga) ocean‐atmosphere system is hypothesized to have experienced fluctuations in redox conditions with transient oxygenation events. One of these happened at ∼1.4 Ga, and it is speculated that this event may link to the emplacement of large igneous province (LIP) at this time. However, direct evidence for this relationship remains to be proved. Here, we report Hg/TOC, P, and trace element concentrations across the ∼1.4 Ga oxygenation event in the Xiamaling Formation of North China. A prominent increase in Hg/TOC is slightly earlier than that of nutrient contents (especially P), pyrite and TOC abundances, suggesting that this distinct oxygenation event was likely the result of LIP activity at ∼1.4 Ga, which increased nutrient and sulfate supply from continental weathering to the ocean, sustaining elevated primary productivity, organic carbon and pyrite burial. This study indicates that LIP weathering could trigger transient oxygenation events during the mid‐Proterozoic. Plain Language Summary: The mid‐Proterozoic (∼1.8–0.8 Ga) retains persistent low oxygen concentrations in atmosphere and shallow seawater but is occasionally punctuated by transient oxygenation events. Multiple lines of evidence from sedimentary geochemistry have argued a global oxygenation event at ∼1.4 Ga, and speculated that this event was closely related to large igneous province (LIP) activity at this time. Direct link between LIP activity and the oxygenation event, however, has rarely been addressed yet. As mercury in sedimentary rocks has been widely used to trace volcanism, we therefore report Hg/TOC, P, and trace element concentrations across the ∼1.4 Ga oxygenation event. The result shows that a prominent increase in Hg/TOC is clearly recognized in the shales that stratigraphically just underly the layers recording the oxygenation event, suggesting a close causal link between LIP emplacement and the oxygenation event. Accompanied with this Hg/TOC ratio peak, increased nutrient contents (especially P), pyrite and TOC abundances are also observed. Based on these observations, we proposed a model that the Xiamaling oxygenation event was the result of the LIP's emplacement at ∼1.4–1.35 Ga, which increased nutrient and sulfate supply from continental weathering to the ocean, sustaining elevated primary productivity, organic carbon and pyrite burial. Key Points: High Hg/TOC ratios associated with large igneous province (LIP) emplacement were detected in the ∼1.4 Ga Xiamaling Formation shales of North ChinaHigh P content accompanied with this interval indicates enhanced phosphorous input from LIP weathering to the oceanA causal link between the LIP weathering and oxygenation event at ∼1.4 Ga was suggested [ABSTRACT FROM AUTHOR]

Among nearly 300 near‐Mercury tail current sheet crossings performed by the MESSENGER spacecraft, we identified 37 traversals of an asymmetric current sheet, wherein the lobe densities on opposite sides differ by a factor of three or more. These asymmetric current sheet crossings primarily occur on the dawnside. A global magnetohydrodynamic (MHD) simulation was found to be in excellent agreement with the observations. The results suggest that the north–south density asymmetry is caused by solar wind entering via an upstream‐connected window in one hemisphere. Furthermore, the Parker spiral interplanetary magnetic field (IMF) controls the near‐tail density asymmetries, whereas Mercury's offset dipole magnetic field controls those in mid‐ or distant‐tail regions. We propose that hemispheric asymmetries in Mercury's magnetospheric convection occur under strong IMF conditions. Plain Language Summary: Mercury possesses a small magnetosphere owing to its weak planetary magnetic field and strong interactions with the solar wind in the inner heliosphere. The transport process of the solar wind mass and energy into its magnetosphere remains unclear. Previous MESSENGER observations suggest that although the Earth‐like plasma mantle is detected inside the near‐tail magnetopause in normal IMF magnitudes, it is not a permanent feature of Mercury's magnetosphere. Here we report, for the first time, that solar wind ions can enter deep into the near‐tail region via an upstream‐connected window in one hemisphere and form a density‐asymmetric current sheet under strong IMF conditions. Through MHD simulations, we revealed tail dawn–dusk asymmetries during the transport of solar wind plasma. Advanced data expected from BepiColombo will further improve our understanding of the solar wind–magnetosphere coupling. Key Points: North–south asymmetries exist in Mercury's magnetotailBoth the interplanetary magnetic field (IMF) BX polarity and intrinsic offset dipole magnetic field control the north–south density asymmetry in Mercury's tailThe IMF Parker spiral results in a dawnside preference for the plasma asymmetric current sheet [ABSTRACT FROM AUTHOR]

Modified silver nanoparticles with a self‐assembled disulfide functionalized 2,2'‐bipyridine (L1 and L2) monolayer, and the corresponding rhenium complex [Re(L2)(CO)3Br] are shown to provide a method to position the nanoparticles at a water/dichloromethane interface forming a lustrous metal‐like‐liquid film (MeLLF) with a unique SERS response. The film formed using L2 showed divergent behaviour in the presence of a range of metal ions whilst bound to the surface. [Re(L)(CO)3Br] (where L=2,2'‐bipyridine, L1 and L2) in solution demonstrates a selective interaction with Hg2+, observed by UV‐vis, emission and 1H NMR spectroscopy, attributed to abstraction of the bromide. This interaction was demonstrated by subtle changes in the characteristic Raman Re‐CO stretch at 510 cm−1 both with the MeLLF, and when the film is immobilized in a PVA surface‐exposed‐nano‐sheet (SENS). The work provides proof of concept that the organometallic complexes can be employed as "labels" to generate SERS‐active nanoparticle films that possess detection capabilities. [ABSTRACT FROM AUTHOR]

In response to the growing concerns surrounding water pollution and the presence of multiple metal ions in environmental matrices, we conducted a comprehensive study to explore the potential of a thiosemicarbazone Schiff base in the Zeolitic Imidazolate Framework (TSC‐ZIF‐1) as an efficient adsorbent for removing harmful metal ions from aqueous solutions. Our investigation assessed the adsorption capacity and efficiency of TSC‐ZIF 1 towards three key metal ions—Hg(II), Ag(I), and Pb(II)—in homo‐ionic, tertiary, and multi‐metal ion systems. TSC‐ZIF 1 exhibited unprecedented adsorption behavior towards all three metal ions in the homo‐ionic system, with the Langmuir isotherm models fitting well (R2 ~ 0.98 to 0.99). The maximum adsorption capacities were found to be 1,667 mg/g for Hg(II), as previously reported; 285 mg/g for Ag(I); and 769 mg/g for Pb(II); these values serve as baseline values. Subsequently, we conducted a comparative analysis for a tertiary system, Hg(II)/Ag(I)/Pb(II), where the three metals co‐existed in one solution. The adsorption capacity for each metal ion was reduced to varying extents; notably, the adsorption capacity for Pb(II) experienced the most significant reduction, reaching a qm value of 57 mg/g, representing an ~93% decrease compared to the homo‐ionic metal system. Conversely, the adsorption capacity for Ag(I) exhibited a minor decrease of ~3%. Despite a decrease in the adsorption capacity for Hg(II) by approximately 34%, the removal capacity remains the highest among the other metals. Our investigation of the competitive adsorption among the metal ions in the Hg(II)/Ag(I)/Pb(II) system revealed an antagonistic effect, indicating strong adsorption competition for available sites on TSC‐ZIF 1. When extending this study to a more complex multi‐metal ion system containing six metal ions, TSC‐ZIF 1 exhibited high selectivity (higher than 60% removal) towards Hg(II), Ag(I), and Pb(II) in a multi‐ionic system, including Hg(II), Ag(I), Pb(II), Cd(II), Ni(II), and Mg(II). [ABSTRACT FROM AUTHOR]

The deposition of different atmospheric mercury (Hg) species into oceans determines the atmospheric Hg lifetime and the production of neurotoxin methylmercury. Yet, the relative contribution of atmospheric Hg(II) and Hg(0) is largely unconstrained. Here, we report the concentrations of total Hg and methylmercury, as well as Hg isotope composition in living corals collected from the tropical South China Sea (SCS). The results show that the Hg in corals is mainly present as inorganic Hg, exhibiting slightly negative δ202Hg and small yet significant Δ199Hg and Δ200Hg. These isotope features closely resemble those of pelagic waters, suggesting that shallow‐water corals that are widely distributed in oligotrophic waters could be used to trace atmospheric Hg deposition pathways. A mixture model based on coral Δ200Hg indicates that approximately 49% of the seawater Hg in the tropical SCS, a region characterized by high rainfall, originates from atmospheric gaseous Hg(0), much larger than previous estimates. Plain Language Summary: Mercury (Hg) is a toxic heavy metal pollutant that has significant impacts on the environment. The ocean plays a crucial role in the global Hg cycle, with atmospheric Hg deposition being a major source of Hg in seawater. By elucidating the sources, transport, and transformations of Hg in the marine environment, we can develop effective strategies for its mitigation and environmental management. However, our current understanding of how atmospheric mercury enters the open sea is limited, due to challenges in directly measuring trace amounts of mercury in seawater. The widely distributed shallow‐water coral could be an important supplement. Here we present the first‐ever examination of mercury isotope compositions in coral polyps and their symbiotic zooxanthellae from the tropical South China Sea to investigate atmospheric Hg sources into the open ocean. The result shows that the ratio of atmospheric divalent Hg(II) to elemental Hg(0) deposition derived from coral isotopes is only about one quarter of the estimate based on current observations. Our study presents a novel approach to constrain atmospheric Hg deposition pathways into the ocean and challenges the prevailing viewpoint that Hg in tropical oceans mainly originates from precipitation. Key Points: First study of Hg isotope compositions in coral polyps and their symbiotic zooxanthellaeShallow‐water coral tissue can serve as an archive for Hg isotopic compositions of the surface seawaterCoral Δ200Hg reveals that ∼49% of seawater Hg in the tropical South China Sea is derived from atmospheric gaseous elemental Hg [ABSTRACT FROM AUTHOR]

This research involves evaluating the use of modified orange peel (MOP) in the removal of Pb2+ and Hg2+ from wastewater. For the modification process, certain concentrations of ethanol, NaOH, and CaCl2 solution were added to the washed and dried orange peel and kept at room temperature for 24 hours. The mixture was then subjected to filtration and rinsed with distilled water until the pH level reached 7. For this reason, the effects of Pb2+ and Hg2+ on the adsorption efficiency were examined by performing batch experiments. The surface properties of MOP were investigated using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT‐IR) techniques. The results revealed that, among the various models, the Langmuir isotherm model provided the best fit to the isotherm data for Hg2+ and Pb2+ ions. Based on the kinetic data of adsorption, the pseudo‐second‐order kinetic model provided a more accurate description of the adsorption process for Pb2+ and Hg2+ ions. According to thermodynamic analyses, both metal ions bind to MOP spontaneously and endothermally. MOP was determined to be a reliable and valid alternative material for the removal of Pb2+ and Hg2+ from aqueous environments based on its qualities such as high adsorption capacity, ease of availability, low cost, use of agricultural waste, recycling potential, and no environmental impact. [ABSTRACT FROM AUTHOR]

Climate‐driven changes including rising air temperatures, enhanced permafrost degradation, and altered precipitation patterns can have profound effects on contaminants, such as mercury (Hg), in High Arctic lakes. Two physically similar lakes, East Lake and West Lake at the Cape Bounty Arctic Watershed Observatory on Melville Island, Nunavut, Canada are being affected by climate change differently. Both lakes have experienced permafrost degradation in their catchments; however, West Lake has also undergone multiple underwater Mass Movement Events (MMEs; beginning in fall 2008), leading to a sustained 50‐fold increase in turbidity. This provided the unique opportunity to understand the potential impacts of permafrost degradation and other climate‐related effects on Hg concentrations and body condition of landlocked Arctic char (Salvelinus alpinus), an important sentinel species across the Circum‐Arctic. Our objectives were to assess temporal trends in char Hg concentrations and to determine potential mechanisms driving the trends. There was a significant decrease in Hg concentrations in East Lake char, averaging 6.5%/year and 3.8%/year for length‐adjusted and age‐adjusted means, respectively, from 2008 to 2019. Conversely, in West Lake there was a significant increase, averaging 7.9%/year and 8.0%/year for length‐adjusted and age‐adjusted mean Hg concentrations, respectively, for 2009 to 2017 (the last year with sufficient sample size). The best predictors of length‐adjusted Hg concentrations in West Lake were carbon and nitrogen stable isotope ratios, indicating a shift in diet including possible dietary starvation brought on by the profound increase in lake turbidity. Our study provides an example of how increasing lake turbidity, a likely consequence of climate warming in Arctic lakes, may influence fish condition and Hg concentrations. Environ Toxicol Chem 2023;42:2712–2725. © 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada. [ABSTRACT FROM AUTHOR]

The removal of heavy toxic metals from industrial effluents is extremely important, especially for mercury (Hg), which is classified as a highly toxic even at low concentrations. For this purpose, novel thiourea chelating resins were synthesized as sorbent for Hg (II). Six different polymers of formo‐phenolic types were characterized and evaluated for their chelating properties with respect to Hg (II) extraction. Batch adsorption studies of mercury (II) as a function of pH, initial metal ion concentration, temperature, and time showed that thiourea formo‐phenolic polymers have a good affinity for Hg removal and a high adsorption capacity. Adsorption isotherms (Langmuir and Freundlich) and kinetic models (pseudo‐first and pseudo‐second order) were used to interpret the sorption behavior of the materials. The Langmuir model yielded the best fit with a maximum adsorption capacity of 300 mg/g. Desorption studies were performed with aqueous thiourea solution and showed that the adsorbent is indeed regenerable and can be effectively used for up to three adsorption‐desorption cycles with negligible loss of performance. This study confirmed the potential of thiol‐modified formo‐phenolic resins in sorbent engineering with promising applications in the remediation of mercury‐contaminated water. [ABSTRACT FROM AUTHOR]

A calix[4]arene‐based gelator 1, with lower‐rim mono triazolylpyridine group, capable of spontaneous self‐assembly into microspheres in different ethanol/H2O mixtures, is synthesized. The concentration‐dependent 1H NMR spectra and X‐ray single‐crystal structure of 1 provided evidence for self‐assembly of gelator 1 via cooperative interactions of intermolecular noncovalent forces. Furthermore, metallogels by self‐assembly of 1 was found to exhibit remarkable selectivity toward Hg2+ ions. 1H NMR spectra support that Hg2+ ion was bound to the nitrogen atoms of two coordination sites of 1, which composed of triazole and pyridine. Moreover, the results of field emission scanning electron microscopy and rheology experiments indicated that Hg2+ ions not only enhanced the gelling ability of gelator 1 in ethanol but also led to morphological change of its self‐assembly through metal‐ligand interactions. Finally, the in situ gelation, triggered by mixing a gelator solution of 1 in ethanol with water samples such as deionized (DI), tap, and lake water, leads to the effective removal of Hg(II) from a water sample which reduced from 400 to 1.6 ppm. [ABSTRACT FROM AUTHOR]

Volcanism is the largest natural source of mercury (Hg) to the biosphere. However, past Hg emission estimates have varied by three orders of magnitude. Here, we present an updated central estimate and interquartile range (232 Mg a−1; IQR: 170–336 Mg a−1) for modern volcanic Hg emissions based on advances in satellite remote sensing of sulfur dioxide (SO2) and an improved method for considering uncertainty in Hg:SO2 emissions ratios. Atmospheric modeling shows the influence of volcanic Hg on surface atmospheric concentrations in the extratropical Northern Hemisphere is 1.8 times higher than in the Southern Hemisphere. Spatiotemporal variability in volcanic Hg emissions may obscure atmospheric trends forced by anthropogenic emissions at some locations. This should be considered when selecting monitoring sites to inform global regulatory actions. Volcanic emission estimates from this work suggest the pre‐anthropogenic global atmospheric Hg reservoir was 580 Mg, 7‐fold lower than in 2015 (4,000 Mg). Plain Language Summary: Volcanism is widely recognized as the most important natural source of mercury (Hg) globally, but existing emissions estimates contain substantial uncertainty. This study combines satellite observations of sulfur dioxide (SO2) in volcanic plumes and measured Hg:SO2 ratios to quantify the magnitude and spatiotemporal variability of global volcanic Hg emissions. Using a global model, we show that the spatial pattern of volcanic releases and atmospheric dynamics result in greater concentrations of volcanic Hg in the mid‐latitude Northern Hemisphere compared to the mid‐latitude Southern Hemisphere. Modeling results suggest that variability in volcanic Hg emissions at some locations may obscure trends in atmospheric Hg concentrations driven by human emissions. The influence of volcanic Hg emissions should therefore be considered during selection of global monitoring sites used to track the progress of regulatory actions designed to mitigate Hg pollution. Volcanic release estimates from this work suggest the natural atmospheric Hg reservoir was ∼7 times smaller than in 2015, reinforcing that humans have profoundly disrupted the global biogeochemical Hg cycle. Key Points: Volcanic mercury emissions of 232 Mg a−1 (IQR: 170–336 Mg a−1) are estimated by indexing to sulfur dioxide from satellite remote sensingOver 90% of volcanic mercury emissions occur in the tropics and mid‐latitude Northern HemisphereVolcanic emissions support a pre‐anthropogenic atmospheric mercury reservoir of approximately 580 Mg (7‐fold lower than in 2015) [ABSTRACT FROM AUTHOR]

The effective governance of Hg2+ in environmental wastewater is of profound significance to deal with the global pollution issues. However, the present methodologies usually only focused on a single function of either detection or removal, which encounters severe secondary pollution and cumbersome operation cost, while the integration of Hg2+ detection, removal, and recovery in one process is barely realized. In this study, an All‐In‐One photoelectrochemical system is built combining the detection, removal, and recovery of Hg2+ pollutant in a single process, by ingeniously developing a fundamental principle, namely alloying‐induced plasmonic quenching mechanism in Schottky heterostructures. Briefly, the high‐efficiency removal and recovery of Hg2+ in wastewater is realized via the favorable alloying of Hg in Ag nanoparticles that well‐dispersed on the free‐standing WO3 nanoplate networks. The formation of Ag–Hg alloy future leads to a remarkable plasmonic quenching effect of the Ag nanoparticles, which is used to modulate the photoelectrochemical singles to realize the high‐precision detection. Through this ingenious design, an ultralow Hg2+ detection limit of 0.296 nm is achieved with a broad detection range up to 12.5 µm, and meanwhile realize a removal/recovery rate of 100% in single Hg2+ solution and 97 ± 2% in industrial wastewater with multiple contamination ions. The detection and removal/recovery performance parameters reported in the study are much better as compared to the recently reported single function detection or removal/recovery systems. This work opens a fresh avenue in tackling the problem of heavy metal pollution using plasmonic Schottky heterostructure based All‐In‐One systems. [ABSTRACT FROM AUTHOR]

Per‐ and polyfluoroalkyl substances (PFAS) and mercury (Hg) are harmful compounds that are widely present in the environment, partly due to spills and atmospheric pollution. The presence of PFAS and Hg in the tissues of animals that are harvested by rural and Indigenous Alaskans is of great concern, yet fish in Arctic Alaska have not previously been assessed for concentrations of PFAS. Fish species of subsistence and recreational importance were collected from nearshore Beaufort and Chukchi Sea, Alaska habitats and assessed for PFAS and total mercury concentrations [THg]. We found multiple PFAS compounds present at low levels (<3 μg/kg) in the muscle tissue of inconnu, broad whitefish, Dolly Varden char, Arctic flounder, saffron cod, humpback whitefish, and least cisco. In addition, [THg] levels in these fish were well below levels triggering local fish consumption guidelines (<170 μg/kg). These initial results indicate no evidence of the Alaska Arctic nearshore fish species examined as an avenue of PFAS or Hg exposure to people who harvest them. However, sources and trends of these contaminants in the Arctic require further investigation. Environ Toxicol Chem 2023;42:2329–2335. © 2023 SETAC [ABSTRACT FROM AUTHOR]

A novel modified carbon paste electrode has been developed using a laboratory synthesized metal chelating ligand (L), N1‐hydroxy‐N1,N2‐diphenylbenzamidine (HDPBA) and multi‐walled carbon nanotubes (MWCNTs) composite (L‐MWCNTs/CPE). The developed modified electrode was applied for selective and sensitive simultaneous electrochemical determination of cadmium(II), lead(II), and mercury(II) using square wave anodic stripping voltammetry (SWASV). The accumulation of metal ions on the electrode surface was performed in 0.1 M acetate buffer solution (ABS, pH 5.0) by applying a potential of–1.10 V versus Ag/AgCl for 210 s, followed by stripping in the positive potential scan of the SWASV after a rest time of 10 s. Under the optimum experimental conditions, the linear dynamic ranges were found to be 2×10−4–2, 1×10−4–2 and 2×10−3–2 μM of cadmium(II), lead(II), and mercury(II), respectively, with the detection limits (LODs) of 2.5×10−2, 7.8×10−3 and 4.6×10−1 nM for cadmium(II), lead(II), and mercury(II), respectively. The proposed electrode exhibited high sensitivity for the determination of these metal ions with excellent reproducibility and stability. The influence of several ions on the simultaneous determination of Cd(II), Pb(II), and Hg(II) was studied, and the prepared electrode was found to be highly selective for the detection of the three metal ions. The developed electrode was effectively applied to the determination of the three metal ions in water, vegetable and tobacco samples, and the obtained results were similar to those measured with graphite furnace atomic absorption spectrometry (GFAAS). [ABSTRACT FROM AUTHOR]

Background: The role of contact sensitisation in the pathogenesis of oral lichen planus (OLP) has not been clearly defined. Objective: We aimed to evaluate relevant contact sensitisers in OLP. Methods: A retrospective study was conducted on OLP patients who underwent patch testing from 1 January 2006 to 31 December 2020 at an Australian tertiary dermatology institution, compared to cheilitis patients patch tested over the same time period. Results: Ninety‐six OLP patients and 152 cheilitis patients were patch tested during the 15‐year period. Seventy‐one (73.9%) OLP patients and 100 (65.8%) cheilitis patients recorded one or more relevant reactions. Forty‐three (44.8%), 22 (22.9%), 21 (21.9%) and 17 (17.7%) OLP patients had relevant reactions to mercury‐related chemicals, amalgam, spearmint and carvone, respectively, compared to 6 (3.9%), 3 (2.0%), 4 (2.6%) and 0 (0%) cheilitis patients, respectively (p‐value <0.001 each). Four (4.2%) OLP patients had relevant positive reactions to sodium metabisulfite, compared to none in the cheilitis group (p‐value 0.021). Conclusion: While dental amalgam is used less frequently these days, we report that mercury (found in amalgam) and additionally spearmint and carvone are relevant sensitisers in OLP in Australia. Sodium metabisulfite may also be a relevant sensitiser in OLP, which has not previously been reported. [ABSTRACT FROM AUTHOR]

One of the UN Sustainable Development Goals is to ensure universal access to clean drinking water. Among the various types of water contaminants, mercury (Hg) is considered to be one of the most dangerous ones. It is mostly its immense toxicity and vast environmental impact that stand out. To tackle the issue of monitoring water quality, a nanosensor based on carbon dots (CDs) is developed, whose surface is functionalized with carboxylic groups. CDs show Hg2+ concentration‐dependent photoluminescence (PL) lifetimes along with an ultrahigh sensitivity and selectivity. The selectivity of PL quenching by Hg2+ is rationalized by performing light‐induced electron paramagnetic resonance (LEPR) spectroscopy showing significant perturbation of the CD photoexcited state upon Hg2+ binding. The experimental findings are supported by time‐dependent density functional theory (TD‐DFT) calculations. These unveiled the emergence of a low‐lying charge transfer state involving a vacant 6s orbital of Hg2+ stabilized by relativistic effects. [ABSTRACT FROM AUTHOR]

Much has been published about the harmful effects to humans when they are exposed to mercury (Hg) in environmental media including their diet. Numerous health advisories around the world, including for the South River, Virginia, USA, warn against consumption of Hg‐contaminated fish species. Fewer studies have focused on other dietary sources of Hg and how to advise humans potentially exposed by this route. In undertaking a human health risk assessment for the former DuPont facility in Waynesboro, Virginia, USA, and the nearby South River and surrounding watershed, the available published information on Hg exposure through dietary consumption of nonfish items proved unsuitable for extrapolation purposes. In response, an evaluation of potential Hg exposure to residents who might consume livestock, poultry, and wildlife raised or collected in the South River watershed was conducted to inform the risk‐assessment process. The newly collected data on Hg in these dietary items filled an important data gap, suggesting that there was little concern about limiting dietary consumption for most items. These results were communicated to the public through print and electronic platforms, in the form of "fact sheets." We describe the studies and actions taken to better explain the potential for human exposures to Hg in nonfish dietary items from a portion of the watershed of the South River. Environ Toxicol Chem 2023;42:2237–2252. © 2023 SETAC [ABSTRACT FROM AUTHOR]

Toxic metal or element exposure has the potential to cause significant negative health effects in human populations. During the goldrushes of the colonial period, mercury amalgamation was one of the most common methods of extracting gold from alluvial deposits or crushed ore, and exposure to mercury was an occupational health hazard. In this study we examine mercury exposure in mining populations from New Zealand's first major goldrush, which began in Central Otago in 1861. We explore mercury toxicity through laser ablation inductively coupled mass spectrometric analysis of archaeological hair and sediment samples associated with the Tuapeka goldfields. Our analysis highlights ubiquitous low‐level mercury exposure on the goldfields, as well as one individual with such high mercury concentrations in their hair that we suspect direct mercury intake, perhaps medicinally, rather than from environmental contamination. [ABSTRACT FROM AUTHOR]

Mercury is a pollutant that poses a considerable health risk. The concentration of mercury in scalp hair can be used to estimate past mercury exposure. Methods such as atomic absorption spectrophotometry and inductively coupled plasma‐based techniques have been used to determine the concentrations of trace elements in scalp hairs; however, these analytical methods have several limitations, including the need for expensive equipment, complex sample preparation, and large samples of more than 100 hairs. Therefore, simpler and more cost‐effective methods are required. X‐ray fluorescence (XRF) spectroscopy is a simple and fast analytical method. To improve the sensitivity, we applied a secondary target method to enhance the XRF excitation and reduce the background. In conventional secondary target methods, the primary x‐rays irradiate a secondary target of a pure substance, and the sample is then irradiated with the fluorescent x‐rays from the secondary target. We placed high‐purity Y₂O₃ powder, which served as the secondary target, behind the hair samples. The XRF intensities of trace elements such as mercury and zinc in the hair were enhanced by applying the secondary target behind the hair. [ABSTRACT FROM AUTHOR]

Herein, a new tellurium and mercury containing mercuraazametallamacrocycle has been prepared via (2+2) condensation of bis(o‐aminophenyl)telluride and bis(o‐formylphenyl)mercury(II). The isolated bright yellow solid of mercuraazametallamacrocycle has adopted unsymmetrical figure‐of‐eight conformation in the crystal structure. To study the metallophilic interactions between closed shell metal ions, the macrocyclic ligand has been treated with two equiv. of AgOTf (OTf=trifluoromethansulfonate) and AgBF4, which afforded greenish‐yellow bimetallic silver complexes. The isolated silver complexes displayed intramolecular Hg⋅⋅⋅Ag, Te⋅⋅⋅Ag interactions as well as intermolecular Hg⋅⋅⋅Hg interactions and formed an extended 1D molecular chain by directing six atoms to interact as TeII⋅⋅⋅AgI⋅⋅⋅HgII⋅⋅⋅HgII⋅⋅⋅AgI⋅⋅⋅TeII in a non linear fashion. The Hg⋅⋅⋅Ag, Te⋅⋅⋅Ag interactions have also been studied in solution by 199Hg, 125Te NMR spectroscopy, absorption, and emission spectroscopy. In DFT calculations, the Atom in Molecule (AIM) analysis, non‐covalent interactions (NCI), natural bonding orbital (NBO) analysis strongly supported for experimental evidences and revealed that the intermolecular Hg⋅⋅⋅Hg interaction is stronger than the intramolecular Hg⋅⋅⋅Ag interactions. [ABSTRACT FROM AUTHOR]

The interactions between habitat fragmentation and other stressors are considered a key knowledge gap. The present study tested the hypotheses that mercury enhances the effects of fragmentation by (1) reducing the cumulative daily movement of organisms, (2) shifting their foraging behavior, and (3) altering the vertical movement of the marsh periwinkle (Littoraria irrorata) in a field experiment. Random walk simulations were used to access how changes in movement affect the search efficiency of organisms in the long term. Eighteen 1.5 m2 plots were constructed in a salt marsh where landscapes characteristics were manipulated to reach three different levels of habitat cover. Daily movement of 12 marked control and mercury‐exposed snails were measured in each plot. Bayesian models were used to analyze the data and evidence ratios were used to test the hypotheses. The results showed that the effects of fragmentation were consistent in both control and exposed treatments, with an increase in the cumulative displacement of organisms. However, mercury significantly reduced the movement of organisms in all levels of fragmentation, shifting their foraging behavior (evidence ratio > 1000). Exposed snails were more likely to be found inactive in comparison with the control treatment (evidence ratio > 1000). Fragmentation also reduced the vertical movement of organisms in both treatments. In contrast, mercury increased the vertical movement of organisms (evidence ratio > 1000). The search efficiency of organisms also increased in a highly fragmentated landscape, suggesting that changes in foraging behavior are likely due to reduced resources and consequently increase in foraging effort. The present study shows that mercury exposure can enhance the effects of habitat fragmentation by changing organisms' movement, foraging behavior, and search efficiency. Environ Toxicol Chem 2023;42:1971–1981. © 2022 SETAC [ABSTRACT FROM AUTHOR]

The article reviews an application of double deposition/accumulation and stripping steps as a new and beneficial manner of decreasing a detection limit and/or interferences elimination in stripping voltammetric determination of inorganic ions: Pb(II), Cd(II), Tl(I), U(VI), Au(III), As(III), Se(IV), In(III), Co(II), Cu(II), Bi(III) and Ga(III). A simple design of four‐electrodes system, containing two working electrodes differing in their surface area, allows for conducting two preconcentration and two stripping steps in one measurement cycle and in one voltammetric cell. Considerable analytes preconcentration and, consequently, an increase of sensitivity of determinations was obtained by conducting the first stripping step in a small volume of a solution near the microelectrode surface. An appropriate selection of the conditions of the first deposition/accumulation and the first stripping steps allowed for a minimization/elimination of interference effects. The proposed procedures allows for ultra‐trace levels determinations of mentioned inorganic ions (often impossible to determine by means of traditional three‐electrodes systems) without additional preconcentration outside the electrochemical cell and with the use of mercury‐free electrodes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Polymetallaynes are a promising branch of metallopolymers, in which the introduction of metal building blocks to organic conjugated backbones leads to their unique skeletons and versatile properties. Notably, the chemical structures, geometric configurations and functional properties in these organometallic systems can be adjusted flexibly by the appropriate selection of metal centers, auxiliary ligands, or bridging spacers. In recent years, both one‐dimensional and two‐dimensional polymetallaynes have attracted considerable attention owing to their excellent electronic, optical and magnetic properties. Furthermore, the studies on molecular metallaynes provide substantial insights for the exploration of the structure‐property‐activity relationships in these organometallic acetylide‐containing systems. The recent research progress of polymeric and molecular metallaynes containing platinum, mercury and gold is discussed in this article. A series of functional properties have been realized in these acetylide‐containing compounds by the rational structural design and refined synthetic strategies, leading to their emerging applications including energy conversion, nonlinear optics, data storage and memory, as well as chemo/biosensing. What is the most favorite and original chemistry developed in your research group? Chemistry plays a key role in providing solutions to many of the challenges facing the world today. In particular, an understanding of chemistry is essential as the basis for medicine and public health, in addressing challenges such as global climate change, in providing sustainable sources of clean energy, and in maintaining the environment for the well‐being of people. We aim at the cutting‐edge research areas of photofunctional metal‐organic molecules and polymers for optoelectronic and energy‐related applications. Photofunctional molecular materials are considered as versatile materials for energy interconversions and optoelectronic/photonic applications, including electrical energy generation in organic solar cells (OSCs) and light generation in organic light‐emitting diodes (OLEDs), as they offer a low cost, light weight and simple option for device fabrication. We have developed new synthetic methods to produce technologically useful materials (e.g., metallopolymers and metallophosphors) with specific functional roles. Such research clearly presents a promising way out of the worldwide energy problem. What is the most important personality for scientific research? Although there is no guarantee of success and practical gains in doing research, it is my belief that our efforts will get harvest if we work hard and do not give up. Patience, diligence, perseverence and confidence are the prerequisites for the successful research study. Besides, there are many good research opportunities in the Greater Bay Area and the Mainland by collaborating with the top researchers there in various joint projects, which would create more impact cases for the betterment of our society. How do you get into this specific field? Could you please share some experiences with our readers? Global energy consumption is depleting non‐renewable fossil fuels at a staggering rate. Mankind's life quality depends on the development of renewable energy sources. As such, our research is dedicated to advancing technologies in energy conversion and translating light into electricity and electricity into light, hence contributing to the sustainability of human life on earth. So, we moved to work in this field by developing molecular materials for fabricating OSCs and OLEDs. These developments are complementary in that solar devices produce energy, and light‐emitting devices save energy. How do you supervise your students? I was deeply inspired by the passion of my former supervisors for research when I did my PhD and postdoctoral studies. Their ability to captivate me with the inherently intriguing essence of science and to share with me their passion for the discipline was particularly rewarding for me. Certain qualities I developed, such as an analytic mind and creative thinking, are the key factors that help me handle my job well nowadays. I hope that young talents will make full use of the word "Chem‐is‐try" to try more in chemical research and explore new interesting science topics. Besides, students can realize the magic of scientific research which probes them to achieve more. [ABSTRACT FROM AUTHOR]

Herein, a newly‐developed material called Thiourea@WOx/Starch Polymer (TH@WOx/SP) is prepared by a one‐pot and high yield solvothermal method. It is not only equipped with porous structure but also has a superior adsorption capacity. The relevant characterizations and adsorption performance are analyzed by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), Zeta potential analysis, and differential pulse voltammetry (DPV). Surprisingly, with its abundant active sites, the TH@WOx/SP reveals its excellent adsorption capacity for heavy metal and organics dye, as high as 2201.16 mg g−1 for Hg(II) and 175.01 mg g−1 for methylene blue (MB), finished within 30 and 90 min, respectively. These satisfactorily fast and high adsorption capacities not only come down to its concave–convex structure, but also to its enriched functional groups serving as anchor sites for Hg(II) and MB. The adsorption mechanism of Hg(II) and MB on TH@WOx/SP is carefully evaluated, which can be attributed to covalent coordination, ion exchange, π–π interactions, hydrogen bonds, and electrostatic attraction. This work designs a new strategy to develop a novel porous metal organic polymer adsorbents and demonstrates its prospective application in the field of adsorption. [ABSTRACT FROM AUTHOR]

Our calculations of the global instability index (G) values for some diamond‐like materials with the general formula I2–II–IV–VI4 have indicated that the structures may be unstable or incorrectly determined. To compute the G value of a given compound, the bond valence sums (BVSs) must first be calculated using a crystal structure. Two examples of compounds with high G values, based on data from the literature, are the wurtz–stannite‐type dicopper cadmium silicon tetrasulfide (Cu2CdSiS4) and the stannite‐type dicopper mercury tin tetrasulfide (Cu2HgSnS4), which were first reported in 1967 and 1965, respectively. In the present study, Cu2CdSiS4 and Cu2HgSnS4 were prepared by solid‐state synthesis at 1000 and 900 °C, respectively. The phase purity was assessed by powder X‐ray diffraction. Optical diffuse reflectance UV/Vis/NIR spectroscopy was used to estimate the optical bandgaps of 2.52 and 0.83 eV for Cu2CdSiS4 and Cu2HgSnS4, respectively. The structures were solved and refined using single‐crystal X‐ray diffraction data. The structure type of Cu2CdSiS4 was confirmed, where Cd2+, Si4+ and two of the three crystallographically unique S2− ions lie on a mirror plane. The structure type of Cu2HgSnS4 was also verified, where all ions lie on special positions. The S2− ion resides on a mirror plane, the Cu+ ion is situated on a fourfold rotary inversion axis and both the Hg2+ and the Sn4+ ions are located on the intersection of a fourfold rotary inversion axis, a mirror plane and a twofold rotation axis. Using the crystal structures solved and refined here, the G values were reassessed and found to be in the range that indicates reasonable strain for a stable crystal structure. This work, together with some examples gathered from the literature, shows that accurate data collected on modern instrumentation should be used to reliably calculate BVSs and G values. [ABSTRACT FROM AUTHOR]

Widespread mercury (Hg) contamination of freshwater systems, due primarily to deposition of atmospheric inorganic Hg (IHg), poses a potential threat to recreational fisheries. In aquatic ecosystems, IHg is converted by bacteria to methylmercury (MeHg), a potent toxin that bioaccumulates in consumers and biomagnifies through the food web, reaching elevated concentrations in fish. Methylmercury has concentration‐dependent sublethal effects on fish, including reductions in reproductive output. In the present study, we conducted the first analysis of the potential health risks of MeHg contamination to largemouth bass (Micropterus salmoides), a popular game fish, in the southeastern United States. To assess the potential health risk posed by MeHg to largemouth bass, we compared MeHg concentrations in three sizes of adult largemouth bass to benchmarks associated with the onset of adverse health effects in fish. We also determined how the risk posed by MeHg to largemouth bass varied spatially throughout the southeastern United States. Our study suggests that in the southeastern United States MeHg poses a potential risk to largemouth bass health and that MeHg contamination may be detrimental to the fisheries of this economically important species of game fish. Environ Toxicol Chem 2023;42:1755–1762. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]