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Contaminants, such as heavy metals (HMs), accumulate in the Arctic environment and the food web. The diet of the Indigenous Peoples of North Greenland includes locally sourced foods that are central to their nutritional, cultural, and societal health but these foods also contain high concentrations of heavy metals. While bacteria play an essential role in the metabolism of xenobiotics, there are limited studies on the impact of heavy metals on the human gut microbiome, and it is so far unknown if and how Arctic environmental contaminants impact the gut microbes of humans living in and off the Arctic environment. Using a multiomics approach including amplicon, metagenome, and metatranscriptome sequencing, we identified and assembled a near-complete (NC) genome of a mercury-resistant bacterial strain from the human gut microbiome, which expressed genes known to reduce mercury toxicity. At the overall ecological level studied through α- and β-diversity, there was no significant effect of heavy metals on the gut microbiota. Through the assembly of a high number of NC metagenome-assembled genomes (MAGs) of human gut microbes, we observed an almost complete overlap between heavy metal-resistant strains and antibiotic-resistant strains in which resistance genes were all located on the same genetic elements. [ABSTRACT FROM AUTHOR]

Sensory disturbances and central nervous system symptoms are important in patients with Minamata disease. In the peripheral nervous system of these patients, motor nerves are not strongly injured, whereas sensory nerves are predominantly affected. In this study, we investigated the mechanisms underlying the sensory-predominant impairment of the peripheral nervous system caused by methylmercury. We found that the types of cell death in rat dorsal root ganglion (DRG) neurons caused by methylmercury included apoptosis, necrosis, and necroptosis. Methylmercury induced apoptosis in cultured rat DRG neurons but not in anterior horn neurons or Schwann cells. Additionally, methylmercury activated both caspase 8 and caspase 3 in DRG neurons. It increased the expression of tumor necrosis factor (TNF) receptor-1 and the phosphorylation of receptor-interacting protein kinase 3 (RIP3) and mixed-lineage kinase domain-like pseudokinase (MLKL). The expression of TNF-α was increased in macrophage-like RAW264.7 cells by methylmercury. The increase was suggested to be mediated by the NF-κB pathway. Moreover, methylmercury induced neurological symptoms, evaluated by a hindlimb extension response, were significantly less severe in TNF-α knockout mice. Based on these results and our previous studies, we propose the following hypothesis regarding the pathogenesis of sensory nerve-predominant damage by methylmercury: First, methylmercury accumulates within sensory nerve neurons and initiates cell death mechanisms, such as apoptosis, on a small scale. Second, cell death triggers the infiltration of macrophages into the sensory fibers. Third, the macrophages are stimulated by methylmercury and secrete TNF-α through the NF-κB pathway. Fourth, TNF-α induces cell death mechanisms, including necrosis, apoptosis through the caspase 8/3 pathway, and necroptosis through the TNFR1-RIP1-RIP3-MLKL pathway, activated by methylmercury in sensory neurons. Consequently, methylmercury exhibits potent cytotoxicity specific to the DRG/sensory nerve cells in the peripheral nervous system. This chain of events caused by methylmercury may contribute to sensory disturbances in patients with Minamata disease. [ABSTRACT FROM AUTHOR]

The purpose of this study was to test the protective effect of Withania somnifera (WS) against the harmful effects of mercuric chloride (HgCl2)‐induced kidney failure at the histological, biochemical, and immune levels in Wistar rats. The study assessed the biochemical and immunological changes in five groups (n = 6): Group 1 (G1) was the negative control, and the other rats received a single subcutaneous dose of HgCl2 (2.5 mg/kg in 0.5 mL of 0.9% saline solution) and randomly divided into 4 groups. Group 2 (G2) was the positive control and left without treatment. Groups 3, 4, and 5 (G3, G4, and G5) were treated with different doses of WS root powder for 30 days. The HgCl2‐positive group showed significant signs of renal toxicity as reflected by increased levels of kidney function parameters (blood urea nitrogen, urea, and creatinine), inflammatory biomarkers, immunological indices (SDF‐1, IL‐6, NGAL, and KIM‐1), and oxidative stress (SOD, TAC, CAT, GSH, and MDA). The positive group rats also showed drastic pathological changes in renal tissues. Different doses of WS treatment significantly reduced the levels of all biochemical markers and decreased pathological damage to the kidney tissues. The antioxidant, phenolic, and flavonoid constituents of WS root powder helped protect rats' kidneys against HgCl2‐induced kidney toxicity in male rats. [ABSTRACT FROM AUTHOR]

Simple Summary: Recent awareness highlights the significant impact of contaminants on the Mediterranean marine ecosystem and fishery resources. Monitoring these pollutants is crucial due to their accumulation in marine organisms and the health risks they pose through consumption. This study examines the levels of total mercury and PAHs in the muscle tissue of European hake from an important fishing ground in the Adriatic Sea. Seasonal and gender patterns as well as correlations with somatic indexes were explored to provide cost-effective bioindicators for pollution monitoring and mitigation. This research investigates the dynamics of contaminant exposure in European hake (Merluccius merluccius, L. 1758) from the Adriatic Sea (Central Mediterranean Sea) by examining the levels of total mercury (THg) and polycyclic aromatic hydrocarbons (PAHs) in the muscle fish tissues. The study explores the correlations between these pollutants and somatic indexes to identify the early warning signals of pollution and ecological effects. The levels of pollutants are influenced by season and sex. Lipids appear to have a minimal effect on the PAH levels, whereas they exhibit a positive correlation with mercury levels in the muscle. No significant relationships between the pollutants and condition indexes were observed, except for a positive correlation between THg and the gonadosomatic index, indicating a potential impact on the reproductive health of fish. In contrast, PAHs showed no meaningful correlation with condition indexes. Differences in contaminant accumulations and lipid levels between sexes reflect variations in metabolic activity, reproductive costs, and adaptive strategies to seasonal changes and energy demands. This study highlights the importance of long-term monitoring to improve pollution management, environmental conservation, and the protection of marine organisms' health. [ABSTRACT FROM AUTHOR]

An inflammatory skin condition called psoriasis results from immune system interactions that are out of balance. Reactive oxygen species are produced as a general mechanism of mercury toxicity. This study aimed to determine whether there was an association between blood total mercury and psoriasis in US adults. Utilizing data from the National Health and Nutrition Examination Survey (NHANES) 2005–2006 and 2013–2014. NHANES is a national research survey program every two years to assess the population's nutritional and physical health. The relationship between blood total mercury and psoriasis was studied using multivariable logistic regression models and smooth curve fitting. Subgroup analysis and interaction tests were used to investigate if this association was stable across populations. After adjusting for several factors, we found a positive association between blood total mercury and psoriasis in 6086 participants. According to the fully adjusted model, each 1-unit increase in blood total mercury was associated with an 8% increase in the prevalence of psoriasis [1.08 (1.03, 1.14)]. The favorable association seems to be more pronounced in non-diabetes. Our research shows a positive association between psoriasis and blood total mercury in US adults. The results of this study need to be supported by additional prospective research. [ABSTRACT FROM AUTHOR]

The Saimaa ringed seal (Pusa hispida saimensis) is a subspecies of ringed seal, landlocked in Lake Saimaa, Finland. The small population of less than 500 seals is facing many human-induced threats, including chemical contaminants. Mercury, in particular, has previously been suggested to be one of the chemicals affecting the viability of this endangered population. We analysed mercury concentrations from placentas and lanugo pup tissues (blubber, brain, kidney, liver, and muscle) to determine current prenatal exposure levels. These pups were found dead in or near birth lairs and were less than 3 months old. Additionally, we used threshold values available in the literature to estimate the potential mercury toxicity to the Saimaa ringed seal. We also determined selenium concentrations for its potential to alleviate the adverse effects of mercury. We further supplemented our study with brain samples collected from various seal age classes. These seals were found dead by either natural causes or by being caught in gillnets. The analysed chemicals were present in all tissues. For lanugo pups, mercury concentrations were the highest in the kidney and liver, whereas the highest selenium to mercury molar ratio was observed in placentas. The toxicity evaluation suggested that, in severe cases, mercury may cause adverse effects in lanugo and older pups. In these cases, the selenium concentrations were low and selenium to mercury ratio was below 1:1 threshold ratio and thus unlikely to provide adequate protection from the adverse effects of mercury. Furthermore, adverse effects are more likely to occur in adult seals, as mercury bioaccumulates, leading to higher concentrations in older individuals. Placental mercury concentrations correlated to those in the livers and muscle tissues of lanugo pups. This, together with the fact that placentas can be collected non-invasively and in good condition, provides a potential novel method for biomonitoring mercury exposure in Saimaa ringed seals. [ABSTRACT FROM AUTHOR]

Simple Summary: Mercury is one of the most common pollutants in agricultural and industrial areas; therefore, its study has become increasingly important. This element is often quantified using biomonitors, whose gradual response is representative of the entire community. This is especially important in areas where pollution is known or suspected, like the Mezquital Valley in central Mexico. Here, we aimed to determine the total mercury concentration in three species of small wild mammals that differ in diet to identify possible exposure threats in their habitat. We took hair and liver samples from two bat species and one wild mouse species over the course of a year. We found no difference in mercury concentration among species, but liver mercury was significantly lower during the dry season. This supports previous studies that pointed to wastewater as the main source of mercury exposure in this location. This is the first study to use small wild mammals as biomonitors in the Mezquital Valley, which is a critically contaminated site, as well as the first record of toxic metals in the protected bat species Leptonycteris yerbabuenae. Mercury (Hg) has been extensively studied due to its impact on the environment and health, but its effects on wild mammal populations are still poorly known. Therefore, the use of biomonitors has gained importance. Our objective was to report and compare, for the first time, the amount of mercury in small mammals belonging to three trophic guilds and to provide an initial toxicology perspective in the Mezquital Valley, a critically polluted area of Central Mexico. We quantified total Hg from the hair and liver of a nectarivorous bat (Leptonycteris yerbabuenae), an insectivorous bat (Corynorhinus townsendii) and a granivorous mouse (Peromyscus melanophrys) using atomic absorption spectrometry during the dry and rainy seasons. We compared the mercury concentrations between seasons, species and matrices. In all species, the average mercury content was higher in hair than liver, and there was no correlation between matrices. There was no difference in mercury content among species. Hg concentrations in the livers of P. melanophrys and C. townsendii were lower during the dry season than the rainy season, suggesting a seasonal decline in mercury availability. All of the values detected were below the neurotoxicity threshold reported in small mammals (10 ppm); however, we propose constant monitoring of Hg in their environment and confirm the utility of these species as biomonitors. [ABSTRACT FROM AUTHOR]

Minamata disease, caused by ingesting seafood contaminated with methylmercury dumped by corporations, was discovered in 1956; however, there has been no continued investigation to determine the full extent of the damage. Since 2004, it has been discovered that affected patients can be found in areas further away from Minamata than previously known. In the present study, we investigated various symptoms and somatosensory disturbances in western Miyanokawachi District, northern Himedo District, southwestern Nagashima District, and the uncontaminated Amami district and calculated the proportion of patients with sensory disturbances as a percentage of the population in each area. Both touch and pain sensations, with a predominance of the peripheral extremities, were observed in 58.6% of patients in Miyanokawachi, 53.9% in Himedo, 37.8% in Nagashima, and 1.4% in Amami. The lowest estimates of attributable fractions of the exposed group for four-limb-predominant sensory disturbance in the population of the contaminated districts were 94.1% in Miyanokawachi, 94.6% in Himedo, and 91.4% in Nagashima, and general and perioral sensory disturbances were also high. This suggests that the presence or absence of these sensory disturbances is useful in the diagnosis of Minamata disease, even in more distant parts of the Yatsushiro Sea area. [ABSTRACT FROM AUTHOR]

Mercury, particularly in its methylated form, poses a significant environmental and health risk in aquatic ecosystems. While the toxicity and bioaccumulation of mercury are well documented, there remains a critical gap in our understanding of the mechanisms governing mercury methylation and demethylation in aquatic environments. This review systematically examines the complex interplay of chemical, biological, and physical factors that influence mercury speciation and transformation in natural water systems. We provide a comprehensive analysis of methylation and demethylation processes, specifically focusing on the dominant role of methanogenic bacteria. Our study highlights the crucial function of hgcAB genes in facilitating mercury methylation by anaerobic microorganisms, an area that represents a frontier in current research. By synthesizing the existing knowledge and identifying key research priorities, this review offers novel insights into the intricate dynamics of mercury cycling in aquatic ecosystems. Our findings provide a theoretical framework to inform future studies and guide pollution management strategies for mercury and its compounds in aquatic environments. [ABSTRACT FROM AUTHOR]

There has been a significant rise in cancer-related mortality in the Ladakh region during the past 10 years. The most common type of case is gastrointestinal cancer, which has been linked in theory by medical research to lifestyle factors, high altitude conditions, and the prevalence of Helicobacter pylori bacteria brought on by poor hygiene. Nevertheless, the precise cause of the rise in cancer cases is still unknown. Concurrently, there has been a significant change in Ladakh's water use practices due to development, improved basic utilities, and related vocational shifts. The local population has become increasingly reliant on groundwater since it provides a year-round, continuous water supply for home and agricultural uses. In this study, we assessed heavy metal contamination in groundwaters and associated human health risks. The results indicate that 46–96% of the groundwater samples have heavy metal pollution with a health hazard index > 1, which means using these groundwaters for drinking, food preparation, and agriculture is likely to result in carcinogenic and non-carcinogenic health hazards. The main heavy metal contaminants found in the groundwater of the Leh district include Cr, As, Hg, and U. According to the health risk assessment, 46–76% of the groundwater samples contain unsafe levels of Cr and As. Prolonged exposure to these levels is likely to cause gastrointestinal cancer in the local population. Acute to chronic exposure to U and Hg concentrations present in some groundwater samples is likely to result in various non-carcinogenic health risks. [ABSTRACT FROM AUTHOR]

Mercury and lead toxicity in water has serious repercussions on human health. There is an urgent need to develop effective and efficient small moieties for their removal. The convenient one-pot synthesis of a few N3Se3 type small sized moieties is reported herein. The highest metal ion uptake capacity of Hg(II) and Pb(II) ions was found to be 314.3 mg g−1 and 93.5 mg g−1, respectively, by ICP-MS analysis. These ion uptake values are the highest for small sized moieties known in the literature to date. [ABSTRACT FROM AUTHOR]

Thiolate containing mercury(II) complexes of the general formula [Hg(SR) n] 2−n have been of great interest since the toxicity of mercury was recognized. 199Hg nuclear magnetic resonance spectroscopy (NMR) is a powerful tool for characterization of mercury complexes. In this work, the Hg shielding constants in a series of [Hg(SR) n] 2−n complexes are therefore investigated computationally with particular emphasis on their geometry dependence. Geometry optimizations and NMR chemical shift calculations are performed at the density functional theory (DFT) level with both the zeroth‐order regular approximation (ZORA) and four‐component relativistic methods. The four exchange‐correlation (XC) functionals PBE0, PBE, B3LYP, and BLYP are used in combination with either Dyall's Gaussian‐type (GTO) or Slater‐type orbitals (STOs) basis sets. Comparing ZORA and four‐component calculations, one observes that the calculated shielding constants for a given molecular geometry have a constant difference of ∼1070 ppm. This confirms that ZORA is an acceptable relativistic method to compute NMR chemical shifts. The combinations of four‐component/PBE0/v3z and ZORA/PBE0/QZ4P are applied to explore the geometry dependence of the isotropic shielding. For a given coordination number, the distance between mercury and sulfur is the key factor affecting the shielding constant, while changes in bond and dihedral angles and even different side groups have relatively little impact. [ABSTRACT FROM AUTHOR]

A rapid and timely response to the impacts of mercury chloride, which is indispensable to the chemical industry, on aquatic organisms is of great significance. Here, we investigated whether the YOLOX (improvements to the YOLO series, forming a new high-performance detector) observation system can be used for the rapid detection of the response of Daphnia magna targets to mercury chloride stress. Thus, we used this system for the real-time tracking and observation of the multidimensional motional behavior of D. magna. The results obtained showed that the average velocity ( v ¯ ), average acceleration ( a ¯ ), and cumulative travel (L) values of D. magna exposed to mercury chloride stress changed significantly under different exposure times and concentrations. Further, we observed that v ¯ , a ¯ and L values of D. magna could be used as indexes of toxicity response. Analysis also showed evident D. magna inhibition at exposure concentrations of 0.08 and 0.02 mg/L after exposure for 10 and 25 min, respectively. However, under 0.06 and 0.04 mg/L toxic stress, v ¯ and L showed faster toxic response than a ¯ , and overall, v ¯ was identified as the most sensitive index for the rapid detection of D. magna response to toxicity stress. Therefore, we provide a strategy for tracking the motile behavior of D. magna in response to toxic stress and lay the foundations for the comprehensive screening of toxicity in water based on motile behavior. [ABSTRACT FROM AUTHOR]

This article discusses the risks associated with mercury exposure, particularly focusing on at-risk populations in Canada, such as those living in remote areas, individuals living near toxic spills, and those who rely on fish consumption year-round. It underlines the detrimental health effects of mercury exposure, including liver and kidney damage, neurological changes, and developmental issues. The lack of awareness and screening for elevated mercury levels is identified as a significant issue along with the need for greater education regarding possible exposures to mercury. A screening pathway is proposed to aid primary care providers in identifying individuals at risk of elevated mercury levels, with the aim of preventing long-term health complications. Overall, the paper highlights the importance of proactive measures to mitigate mercury exposure and safeguard public health. [ABSTRACT FROM AUTHOR]

Mercury (Hg) pollution around artisanal and small-scale gold mining (ASGM) areas has been of much concern. Many studies have reported elevated Hg concentrations in environmental media, but studies on dust relating to inhalation exposure of Hg around ASGM area are limited. In this study, we investigated Hg in indoor and outdoor dust to reveal environmental and human health risk around ASGM in Amansie West district, Ghana. Indoor and outdoor dust samples were collected from Manso Abore and Manso Nkwanta in Ashanti Region. Concentration of Hg in the samples were analyzed using a direct Hg analyzer. The mean and median value of Hg concentration in the indoor dust (n = 31) were 2.2 ± 3.6 mg/kg and 0.72 mg/kg respectively while that of the outdoor dust (n = 60) were 0.19 ± 0.48 mg/kg and 0.042 mg/kg, respectively. The mean and median Hg concentration in indoor dust were about 11 and 17 times higher respectively than that in the outdoor dust. The Hg concentration in the indoor dust was statistically significantly higher than that of the non-miner in Manso Abore (p < 0.05) but was not significant in Manso Nkwanta, probably due to higher mining activity. The geo-accumulation index of the outdoor dust ranged from unpolluted to extremely polluted while that of the indoor dust ranged from moderately polluted to extremely polluted. Health risk assessments suggested that there was no potential non-carcinogenic health effect for Hg exposure relating to the dust to residents living in rooms of miners and non-miners. [ABSTRACT FROM AUTHOR]

BackgroundAdverse drug reactions (ADRs) to sodium dimercaptosulphonate (DMPS) mercury removal treatment have been reported in occupational mercury poisoning. In recent years, the number of cases of mercury poisoning due to mercury-containing cosmetics has been increasing, and ADRs to the use of DMPS are common in clinical practice.ObjectiveTo investigate the occurrence of ADRs and the influencing factors in patients with chronic mercury poisoning and mercury exposure treated with DMPS for mercury removal.MethodsPatients treated with DMPS due to mercury poisoning at the Occupational Disease Department of Nanjing Prevention and Treatment Center for Occupational Diseases from June 2017 to December 2023 were included in the study. Information on demographics, baseline characteristics, and treatment regimens was collected at admission. Information on secondhand smoke, place of residence, and blood groups not collected at admission was collected in follow-up. The patients were divided into two groups according to whether ADRs occurred after the use of DMPS and were compared for clinical characteristics, and the influencing factors related to the occurrence of ADRs after DMPS treatment were analyzed by binary logistic regression.ResultsA total of 72 patients were enrolled in the study, of which 26 reported ADRs during mercury removal. A total of 29 ADRs occurred, mainly rash in 11 cases (37.9%), fever in 5 cases (17.2%), and nausea in 4 cases (13.8%). Most ADRs occurred in the second course (7 cases, 26.9%) and the third course (9 cases, 34.6%). Of the 22 non-menopausal women who experienced ADRs, 13 (59.1%) used DMPS in the week prior to menstruation. The logistic regression analysis showed that smoking (OR=27.911, 95%CI: 2.835, 725.809) and blood type O (OR=6.885, 95%CI: 2.014, 26.896) were associated with elevated occurrence of ADRs after DMPS treatment.ConclusionsThe probability of ADRs after DMPS treatment is not low, but mild presentations are predominant and resolved with immediate treatment, with a favourable prognosis. The O blood group, smoking individuals, and female patients using DMPS one week before menstruation may be more prone to ADRs.

Fish mercury concentrations result in fish consumption advisories. However, selenium : mercury molar ratios >1 are protective to wildlife and humans. Therefore, we sampled total selenium (TSe) and total mercury (THg) concentrations and molar ratios in sport fish from 50 Idaho (ID) lakes >20 ha and 67 northeastern USA (NE) lakes >1 ha. Sample lakes were selected at random, to obtain unbiased estimates of mean fish tissue levels, with known confidence limits, for target populations of 95 ID lakes >20 ha in surface area and 12,557 NE lakes >1 ha. Bass and salmonids presented the greatest potential mercury toxicity risk to consumers based on their higher mercury content, desirability as game fish, and widespread distributions. Fish tissue THg exceeded safe consumption criteria in an estimated 20–80% of the lakes in the two regions and TSe exceeded safe consumption thresholds in an estimated 0–20% of the lakes in the two regions. However, the Se : Hg molar ratio was >1 in an estimated 90–97% of fish tested from NE and ID lakes. Therefore, we concluded that Se levels in these systems are usually sufficient to limit disruption of selenoprotein activities by Hg, and that fish consumption advisories based on Hg alone are unnecessarily restrictive. [ABSTRACT FROM AUTHOR]

Injection of mercury into the upper limb is a rare method of self-harm. We report two patients with varied clinical presentations – a 19-year-old male student who injected himself with mercury extracted from a sphygmomanometer bulb and reported to our emergency department 24 hours after the event and a 34-year-old industry worker who presented 2 years after injecting himself with elemental mercury. The management of mercury poisoning is described along with a brief review of literature. Mercury is a toxic element and adequate safety precautions must be taken by the surgical team in the management of such patients. Level of Evidence: Level V (Therapeutic) [ABSTRACT FROM AUTHOR]

This article explores the health challenges faced by sled dogs in the Canadian Arctic during the 19th century. As outsiders began to explore the region, they discovered the importance of using dog teams and wearing furs for warmth. However, diseases like distemper and rabies posed a threat to the dogs, with accounts of dogs exhibiting symptoms of hydrophobia (rabies) being recorded. Firsthand accounts from expeditions led by Dr. Elisha Kane and Dr. Isaac Israel Hayes describe the symptoms and deaths of their dogs, although the cause of these health issues remains unclear. The article also discusses the experiences of explorers Charles Francis Hall and Sir George S. Nares, who faced challenges with their dogs, including a mysterious disease that caused seizures and death. The explorers attempted various treatments, some of which may have contributed to the deaths of the dogs. The author emphasizes the need for a better understanding of the fate of these animals and acknowledges the limitations of medical knowledge during that time period. [Extracted from the article]

Aim: Multiple processes have been demonstrated to elucidate the biological toxicity of mercuric chloride, among which oxidative stress has been identified as a contributing factor. The superoxide radical has the potential to induce peroxidation of lipid membranes, alter the activities of proteins and antioxidant enzymes, and modulate gene transcription. Additionally, it has the ability to swiftly deactivate nitric Oxide, resulting in impairment of endothelial function and causing harm to macromolecules, membranes, and DNA by generating more harmful radicals including peroxynitrite and hydroxyl radicals. The formation of nitrotyrosine occurs through the interaction between peroxynitrite and tyrosine residues found in proteins. Nitrotyrosine serves as a useful marker for assessing the possible cytotoxic impacts of nitric oxide. While there have been previous animal tests undertaken, the existing literature we have reviewed does not provide evidence regarding the impact of direct mercury exposure and mercury toxicity on nitrotyrosine and nitric oxide. In order to achieve our research objectives, we have devised a plan to investigate the presence of nitrotyrosine and nitric oxide in the blood serum of children who have been exposed to mercury in our study. Materials and Methods: Our study included 65 patients, 42 girls and 23 boys, who had accidentally come into contact with mercury in the laboratories of some schools in Kahramanmaraş, and whose blood mercury level was over 10 µg/l and/or whose urine mercury level was over 15 µg/l. The control group of the study included a total of 23 children, 17 girls and 6 boys, who applied to the pediatric clinic with various complaints, without intoxication or neurological findings, and from whom blood samples would be taken for different diagnoses. Results: Nitric oxide and nitrotyrosine levels were found to be higher in children exposed to mercury than in the control group (p<0.01). Nitric oxide, nitrotyrosine and mercury levels in the patients were high in both genders, and no gender-related difference was detected (p>0.05). The mean duration of mercury exposure was 45 minutes. Of the 65 patients, 20 were asymptomatic and 40 were symptomatic. The most common symptoms were headache and nausea. Conclusion: The existing body of research predominantly focuses on investigating the association between mercury poisoning and oxidative stress biomarkers through animal studies, with a limited number of studies conducted on human subjects. Our study has made a valuable contribution to the existing literature by successfully detecting elevated levels of nitric oxide and nitrotyrosine in children who have been diagnosed with mercury poisoning. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a global pollutant and a bioaccumulative toxin that seriously affects the environment. Though increasing information has been obtained on the mechanisms involved in mercury toxicity, there is still a knowledge gap between the adverse effects and action mechanisms, especially at the molecular level. In the current study, we screened a diploid library of Saccharomyces cerevisiae single-gene deletion mutants to identify the nonessential genes associated with increased sensitivity to mercury ions. By genome-scale screening, we identified 64 yeast single-gene deletion mutants. These genes are involved in metabolism, transcription, antioxidant activity, cellular transport, transport facilitation, transport routes, and the cell cycle, as well as in protein synthesis, folding, modification, and protein destination. The concentration of mercury ions was different in the cells of yeast deletion mutants. Moreover, the disruption of antioxidant systems may play a key role in the mercurial toxic effects. The related functions of sensitive genes and signal pathways were further analyzed using bioinformatics-related technologies. Among 64 sensitive genes, 37 genes have human homologous analogs. Our results may provide a meaningful reference for understanding the action mode, cellular detoxification, and molecular regulation mechanisms of mercury toxicity. [ABSTRACT FROM AUTHOR]

Mercury is one of the main components of fluorescent lamps. Considering the adverse effects of mercury on human health and the environment, recovery of mercury-containing fluorescent lamps is very important in developed countries. The glass parts of used fluorescent lamps are among the dangerous wastes whose mercury content should be reduced to the lowest possible level according to international standards. The aim of this research is to achieve a systematic approach to minimize the amount of mercury present in fluorescent lamp glass residues according to the European Commission EC95/2002 regulations. In order to extract mercury from glasses, glass pieces were washed with deionized water, using stirring to increase washing efficiency. In order to achieve the maximum amount of extraction, parameters such as ratio of glass to deionized water (S/L), stirring time, temperature and pH were changed. The results showed that, the highest mercury extraction rate is about 98% and in the conditions S/L = 0.1, stirring time of 12 h, temperature of 60 °C and pH 1, which is using a combination of HCl and H3PO4 acid 5% with a ratio of 1:4 has been obtained. The success of this method not only increases environmental sustainability, but also classifies the resulting glass waste as non-hazardous. [ABSTRACT FROM AUTHOR]

Heavy metals exist in the ecosystem both naturally and due to anthropogenic activities and as recalcitrant pollutants; they are non-biodegradable and cause acute and chronic diseases to human beings and many lifeforms. A statistical experimental approach was applied in this current study to optimize the detoxification of mercury [Hg(II)] from mono-component biosorption system by a novel hybrid granular activated carbon (biosorbent) prepared from maize plant residues. The analysis of variance by the application of central composite design shows that all the studied independent factors greatly influence Hg(II) removal efficiency and uptake capacity. The optimum experimental condition of 30 min contact time, 0.5 g/L biosorbent dosage, and 15 mg/L initial Hg(II) concentration were achieved after seeking 20 optimization solutions at 0.903 desirability. The optimum percentage removal and uptake capacity of Hg(II) at the optimal experimental setup was 96.7% and 10.8 mg/g, respectively. To confirm the quadratic models developed for the prediction of the responses as a function of the independent factors, confirmatory laboratory experiments were performed at the optimum condition. The results show that at the established best experimental condition, the optimum Hg(II) removal efficiency of 98.3% and uptake capacity of 11.2 mg/g were attained, which were within the prediction intervals indicating the suitability of the quadratic models in predicting future cases. The TEM and XRD analyses show that the Hg(II) ions were adsorbed by the biosorbent successfully and this suggests the potential and applicability of this novel biosorbent in treating water contaminants, especially heavy metals. [ABSTRACT FROM AUTHOR]

Simple Summary: Mercury is a persistent and toxic metal that can affect marine life. Bottlenose dolphins are particularly vulnerable to mercury accumulation and toxicity because they are top predators and often inhabit near-shore environments with elevated mercury concentrations. This research assessed mercury accumulation in the tissues of bottlenose dolphins that were stranded during two time periods, 2013–2015 (dolphins that were stranded at an unusually high rate; heavily infected with morbillivirus) and 2016–2021 (dolphins that were stranded at a normal rate). We hypothesized that the immunosuppressed individuals would have higher mercury concentrations. Tissue selenium accumulation was also measured, as selenium has been shown to reduce mercury toxicity. Differences in tissue mercury concentrations were not observed between the two time periods; however, the tissue mercury concentrations were higher in adults than juveniles. The selenium distribution in the bottlenose dolphins was significantly different between the two time periods. These results suggest that selenium may not have been as protective against mercury toxicity in the bottlenose dolphins that were stranded during the UME. Bottlenose dolphins (Tursiops truncatus) are long-lived marine mammals, upper-level predators, and they inhabit near-shore environments, which increases their exposure to pollution. Mercury is a ubiquitous and persistent metal pollutant that can bioaccumulate and biomagnify up the food chain. Dolphins are known to accumulate mercury, and limited research has shown that mercury exposure can weaken the immune system of dolphins. The objectives of this study were to assess the mercury concentrations in the tissues (muscle, small intestine, liver) of stranded bottlenose dolphins and to compare the tissue mercury levels in dolphins that were stranded during the 2013–2015 morbillivirus Unusual Mortality Event (UME; immunosuppressed individuals) with the levels of those that were stranded at a normal rate (2016–2021). Selenium has been shown to reduce mercury toxicity in many animals; therefore, tissue selenium concentration and the molar ratio of selenium to mercury were also assessed. The tissue mercury (muscle, liver) and selenium (liver) concentrations increased with the age of the dolphins, with the liver accumulating the highest concentrations. No sex differences were observed in the mercury and selenium concentrations. While differences in tissue mercury concentrations were not observed due to the UME, the selenium accumulation profiles were significantly different between the two time periods. These results suggest that selenium may not have been as protective against mercury toxicity in the bottlenose dolphins that were stranded during the UME, possibly due to infection with morbillivirus. [ABSTRACT FROM AUTHOR]

In Ecuador, illegal gold mining has led to significant environmental impacts, with the release of harmful elements such as mercury (Hg) into the environment. Mercury, due to its physical–chemical characteristics and the transport elements involved between different environmental matrices, can easily percolate through the soil and reach groundwater. The purpose of this study was to evaluate the mercury concentration levels in the Andean region in order to perform a human health risk assessment. For this purpose, 175 water samples were analyzed, of which 9.71% exceeded the maximum permissible limit (MPL) established for drinking water in accordance with Ecuadorian regulations. The risk analysis was conducted by applying two approaches: deterministic and probabilistic. The deterministic approach involves a specific analysis based on the calculation of the risk quotient (HQ) and risk index (HI) for both receptors (adults and children) and scenarios (residential and recreational) considered; the probabilistic approach is based on the use of stochastic simulation techniques. The results obtained from the two approaches show a discrepancy, with the deterministic analysis providing more conservative results; however, they coincide in showing higher risk for the child population; decision-makers could use these results to identify areas to be monitored and plan more detailed investigation plans. [ABSTRACT FROM AUTHOR]

Heterocycles, including imidazole derivatives, are important chemicals due to their structural similarity to active natural molecules. This study explored the utilization of phenylimidazole derivatives for mercury removal from aqueous solutions. Three derivatives were tested, including one harboring a sulfhydryl functional group, thus offering distinct mercury-binding capabilities. Mercury binding experiments revealed modest mercury binding by two derivatives. However, extraordinary efficiency of mercury binding by the sulfhydryl-bearing compound was demonstrated through a reduction in mercury concentrations in pure water by 43-fold in just 15 min and decreasing below the analytical detection limit with prolonged exposure (30 min). Moreover, the ultra-efficiency of mercury binding was demonstrated by a capability to reduce mercury concentrations even in highly contaminated environmental water sample by a factor exceeding 1200-fold in 20 h, using minimal amounts of the compound. This phenylimidazole derivative exhibited comparable efficiency in binding mercury from authentic environmental water samples, hinting at practical applications for real-world remediation efforts. Kinetic investigations showed a pseudo-first order reaction with a rate constant of 0.26 min−1 and half-life of 2.69 min that governs mercury binding to this phenylimidazole derivative. These findings underscore the potential of the sulfhydryl-containing phenylimidazole derivative, as swift and effective binding material for aqueous mercury removal. Its rapid action, coupled with binding efficiency, suggests a promising material for addressing mercury contamination in highly contaminated environmental water samples. [ABSTRACT FROM AUTHOR]

Abstract Background The use of artificial intelligence in the field of health sciences is becoming widespread. It is known that patients benefit from artificial intelligence applications on various health issues, especially after the pandemic period. One of the most important issues in this regard is the accuracy of the information provided by artificial intelligence applications. Objective The purpose of this study was to the frequently asked questions about dental amalgam, as determined by the United States Food and Drug Administration (FDA), which is one of these information resources, to Chat Generative Pre-trained Transformer version 4 (ChatGPT-4) and to compare the content of the answers given by the application with the answers of the FDA. Methods The questions were directed to ChatGPT-4 on May 8th and May 16th, 2023, and the responses were recorded and compared at the word and meaning levels using ChatGPT. The answers from the FDA webpage were also recorded. The responses were compared for content similarity in “Main Idea”, “Quality Analysis”, “Common Ideas”, and “Inconsistent Ideas” between ChatGPT-4’s responses and FDA’s responses. Results ChatGPT-4 provided similar responses at one-week intervals. In comparison with FDA guidance, it provided answers with similar information content to frequently asked questions. However, although there were some similarities in the general aspects of the recommendation regarding amalgam removal in the question, the two texts are not the same, and they offered different perspectives on the replacement of fillings. Conclusions The findings of this study indicate that ChatGPT-4, an artificial intelligence based application, encompasses current and accurate information regarding dental amalgam and its removal, providing it to individuals seeking access to such information. Nevertheless, we believe that numerous studies are required to assess the validity and reliability of ChatGPT-4 across diverse subjects.

Background: The use of artificial intelligence in the field of health sciences is becoming widespread. It is known that patients benefit from artificial intelligence applications on various health issues, especially after the pandemic period. One of the most important issues in this regard is the accuracy of the information provided by artificial intelligence applications. Objective: The purpose of this study was to the frequently asked questions about dental amalgam, as determined by the United States Food and Drug Administration (FDA), which is one of these information resources, to Chat Generative Pre-trained Transformer version 4 (ChatGPT-4) and to compare the content of the answers given by the application with the answers of the FDA. Methods: The questions were directed to ChatGPT-4 on May 8th and May 16th, 2023, and the responses were recorded and compared at the word and meaning levels using ChatGPT. The answers from the FDA webpage were also recorded. The responses were compared for content similarity in "Main Idea", "Quality Analysis", "Common Ideas", and "Inconsistent Ideas" between ChatGPT-4's responses and FDA's responses. Results: ChatGPT-4 provided similar responses at one-week intervals. In comparison with FDA guidance, it provided answers with similar information content to frequently asked questions. However, although there were some similarities in the general aspects of the recommendation regarding amalgam removal in the question, the two texts are not the same, and they offered different perspectives on the replacement of fillings. Conclusions: The findings of this study indicate that ChatGPT-4, an artificial intelligence based application, encompasses current and accurate information regarding dental amalgam and its removal, providing it to individuals seeking access to such information. Nevertheless, we believe that numerous studies are required to assess the validity and reliability of ChatGPT-4 across diverse subjects. [ABSTRACT FROM AUTHOR]

Extraction and mineral processing, as well as the waste generated by old abandoned mining sites, are the main sources of contamination of water bodies and lands by potentially toxic elements (PTEs). The common carp (Cyprinus carpio Linnaeus 1758) has been reported to be a good ecological indicator of environmental pollution in water bodies. Hence, we evaluated the concentration of eleven PTEs (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) in different tissues of common carp in two reservoirs of the province of Jaén, southern Spain: El Tranco de Beas (S1) and La Fernandina (S2). We also assessed the concentration of PTEs in water and sediment samples. We used inductively coupled plasma mass spectrometry for all the collected samples. We found high concentrations of As and Fe in water in the S2 reservoir, above the maximum limits allowed by the sanitary criteria in Spain; however, the analysis of sediments indicated low ecological risk in S1 and moderate ecological risk for As in S2. The concentration of PTEs in common carp was higher in the S2 reservoir, exceeding the permissible limits in the case of As, Cd, Pb, and Zn. As and Cd showed higher concentrations in the kidney; Cu, Fe, and Zn showed higher concentrations in the liver; and Pb and Mn presented higher concentrations in the gill and gill bone. There was a good correlation between the concentrations found in water/sediment samples and those in common carp, corroborating its usefulness as a good ecological indicator, allowing the detection of environmental pollution and inferring previous or current anthropogenic activities such as mining. [ABSTRACT FROM AUTHOR]

Bottlenose dolphins (Tursiops spp.) inhabit bays, sounds, and estuaries (BSEs) throughout the southeast region of the U.S.A. and are sentinel species for human and ecosystem-level health. Dolphins are vulnerable to the bioaccumulation of contaminants through the coastal food chain because they are high-level predators. Currently, there is limited information on the spatial dynamics of mercury accumulation in these dolphins. Total mercury (THg) was measured in dolphin skin from multiple populations across the U.S. Southeast Atlantic and Gulf of Mexico coasts, and the influence of geographic origin, sex, and age class was investigated. Mercury varied significantly among sampling sites and was greatest in dolphins in St. Joseph Bay, Florida Everglades, and Choctawhatchee Bay (14,193 ng/g ± 2196 ng/g, 10,916 ng/g ± 1532 ng/g, and 7333 ng/g ± 1405 ng/g wet mass (wm), respectively) and lowest in dolphins in Charleston and Skidaway River Estuary (509 ng/g ± 32.1 ng/g and 530 ng/g ± 58.4 ng/g wm, respectively). Spatial mercury patterns were consistent regardless of sex or age class. Bottlenose dolphin mercury exposure can effectively represent regional trends and reflect large-scale atmospheric mercury input and local biogeochemical processes. As a sentinel species, the bottlenose dolphin data presented here can direct future studies to evaluate mercury exposure to human residents in St. Joseph Bay, Choctawhatchee Bay, and Florida Coastal Everglades, as well as additional sites with similar geographical, oceanographic, or anthropogenic parameters. These data may also inform state and federal authorities that establish fish consumption advisories to determine if residents in these locales are at heightened risk for mercury toxicity. [ABSTRACT FROM AUTHOR]

Purpose: Pejão Mining Complex locates in Castelo de Paiva municipality and, until its closure in 1994, was one of the most important coal mines in the Douro Coalfield. This work aims to study the presence, quantify, and evaluate the dissemination of mercury (Hg), a potentially toxic element (PTE) of major public health concern by the World Health Organization (WHO), from a waste pile affected by coal fires. Materials and methods: Samples from areas affected and unaffected by the combustion and from surrounding soil were collected from Fojo waste pile region. First, the Hg pseudo-total concentration was estimated for all collected samples by soil microwave–assisted digestion with aqua regia (USEPA 3051A). Then, a sequential extraction procedure (SEP), the USEPA 3200, was applied for Hg fractionation and speciation aiming to evaluate Hg mobility and bioavailability to surrounding ecosystems. Results and discussion: The results obtained showed a Hg enrichment in soil samples when compared to Portuguese and international reference values for soils. Relatively to the Hg availability and mobility, although it predominates in the semi-mobile fraction, the waste pile materials exposed to combustion showed a concerning increase of Hg levels in the mobile fraction that contains the more labile Hg species, being a major source of environmental contamination by Hg. Conclusions: This study allowed to conclude that combustion of mining residues increased Hg mobility, toxicity, and bioavailability, increasing the contamination potential of the coal waste pile. The methodology applied in this work can be replicated in other abandoned mines to monitor, control, and/or mitigate the Hg environmental impact in the surrounding soils and waters. [ABSTRACT FROM AUTHOR]

Methylmercury (MeHg) is a well-known environmental neurotoxicant that causes severe brain disorders such as Minamata disease. Although some patients with Minamata disease develop olfactory dysfunction, the underlying pathomechanism is largely unknown. We examined the effects of MeHg on the olfactory system using a model of MeHg poisoning in which mice were administered 30 ppm MeHg in drinking water for 8 weeks. Mice exposed to MeHg displayed significant mercury accumulation in the olfactory pathway, including the nasal mucosa, olfactory bulb, and olfactory cortex. The olfactory epithelium was partially atrophied, and olfactory sensory neurons were diminished. The olfactory bulb exhibited an increase in apoptotic cells, hypertrophic astrocytes, and amoeboid microglia, mainly in the granular cell layer. Neuronal cell death was observed in the olfactory cortex, particularly in the ventral tenia tecta. Neuronal cell death was also remarkable in higher-order areas such as the orbitofrontal cortex. Correlation analysis showed that neuronal loss in the olfactory cortex was strongly correlated with the plasma mercury concentration. Our results indicate that MeHg is an olfactory toxicant that damages the central regions involved in odor perception. The model described herein is useful for analyzing the mechanisms and treatments of olfactory dysfunction in MeHg-intoxicated patients. [ABSTRACT FROM AUTHOR]

Introduction: This article aimed to analyze the contributions of research related to relevant variables on the current state of safety and health of families of San Jorge by mercury from mining activities, allowing to glimpse possible future consequences to the health of the communities of Ayapel - Córdoba in the Colombian Caribbean from the meanings and practices developed and systematized in the different sources of information. Methodology: The review was carried out from 2010 to 2022 and was conducted through a systematic literature review and meta-analysis following PRISMA using different descriptors in the Scopus, Scielo and PUBMED databases, as well as in the Colombian regulations. Results: socio-environmental, socioeconomic and health and disease categories were obtained where it revealed that primary publications were evidently analytical and sociodemographic, which reveal different socio-environmental and symptomatological problems associated with the toxicity and genotoxicity of mercury coming mainly from artisanal and illegal mining. Conclusions: Conclusions: The studies conducted primarily focus on the department of Córdoba, highlighting the need for research in other regions of the country, with a focus on public health. This implies addressing the raised issue and properly addressing it, theorizing it from other scientific disciplines and from the perspective of public health, promoting new interdisciplinary research lines with the aim of preventing and providing timely knowledge about the health impacts on populations engaged in such practices. [ABSTRACT FROM AUTHOR]

Mercury (Hg) accumulation in rice is a health concern due to the consumption of rice as the staple food. This study evaluated the mercury contamination in rice plants, which are typical foods cultivated in the Red River Delta. During the harvest season, rice samples were collected and separated into husk and brown rice, together with polished white rice and bran rice from mill shop. For brown rice, the Hg concentration ranges from 7.18 ± 0.73 to 16.32 ± 2.57 µg/kg. Additionally, brown rice samples near landfill or highway tend to have higher Hg concentrations than sites farther away. Hazard quotient (HQ) was used to measure the health risk of Hg in this study. HQ values of male and female all were less than one, indicating that consuming rice from Nam Son and Bac Son might not cause potential human health risk of Hg exposure. [ABSTRACT FROM AUTHOR]

Like all life forms, plants suffer from high levels of mercury (Hg), known as one of the most harmful heavy metals in soil. The present study was performed to explore the effects of exogenous nitric oxide (NO) on Hg toxicity in maize (Zea mays L., cv. Arifiye-2) seedlings. Plants were grown in a hydroponic system containing 1/2 diluted Hoagland at 16 h day length, 25/20 °C (day/night) and 60% relative humidity. Eight day-old maize seedlings were first treated with NO (as 0.1 µM sodium nitroprusside) and then they were exposed to Hg toxicity (as 100 µM HgCl2) after 24 h. The toxic Hg decreased seedling growth, chlorophyll content, proline content, calcium and manganese contents, nonenzymatic antioxidant contents, cell membrane viscosity, and antioxidant enzyme activities (superoxide dismutase, catalase, peroxidases, and glutathione reductase) while it increased the generation of reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and super oxide anion (O2.-), and lipid peroxidation (as malondialdehyde, MDA) content and the amount of sodium ion (Na+) in the seedlings. However, NO treatment markedly enhanced the growth parameters (dry and fresh weight, and plant height) and manganese and potassium contents as well as contents of antioxidants and chlorophyll thus alleviating the negative effects caused by the Hg stress. Also, it decreased the generation of ROS and lipid peroxidation level by activating the antioxidant enzymes. These results show that NO in maize seedlings under Hg toxicity may improve stress response and mitigate oxidative stress by stimulating the antioxidant system and modulating ion homeostasis. [ABSTRACT FROM AUTHOR]

Because of their beneficial properties, natural products, especially medicinal plants, are becoming increasingly popular worldwide and play a significant role in research. This study was aimed to evaluate the nephroprotective effect of sinapic acid against mercuric chloride-induced renal toxicity in mice. The mice were allocated to four groups named a normal group (G1), model group (G2; received HgCl2, 1 mg/kg bw), treatments groups (G3 and G4: received 50 and 100 mg/kg bw of sinapic acid together with HgCl2). Mice received HgCl2 remarkably showed alteration in all examined biochemical biomarkers (urea, creatinine, and bilirubin), and induced alteration in blood cell picture and anemia. HgCl2 intoxication decreased both systemic and renal antioxidant activity and induced over all oxidative stress as indicated by alteration in inflammation and oxidative stress associated markers. HgCl2 affected renal histology with leukocytic and inflammatory cell infiltration, fibrosis and tubular necrosis. Administration of sinapic acid (50 and 100 mg/kg bw) markedly restored the HgCl2−induced oxidative stress (serum and renal: MDA, GSH, CAT, SOD, and T-AOC), proinflammatory cytokines (serum and renal: TNF-α, IL-6, IL-1β, and PGE2) and restored the changes on biochemical markers, and hematological parameters (hemoglobin, erythrocytes, platelets, and leukocytes). Taken together, the results of the present study disclose that sinapic acid has the potential to attenuate HgCl2-induced renal toxicity and may be an ideal choice against mercury poisoning. [ABSTRACT FROM AUTHOR]

This article discusses the design and analysis of a new chemical chemosensor for detecting mercury(II) ions. The chemosensor is a hydrazone made from 4-methylthiazole-5-carbaldehyde and fluorescein hydrazide. The structure of the chemosensor was confirmed using various methods, including nuclear magnetic resonance spectroscopy, infrared spectroscopy with Fourier transformation, mass spectroscopy, and quantum chemical calculations. The sensor's ability in the highly selective and sensitive discovery of Hg2+ ions in water was demonstrated. The detection limit for mercury(II) ions was determined to be 0.23 µM. The new chemosensor was also used to detect Hg2+ ions in real samples and living cells using fluorescence spectroscopy. Chemosensor 1 and its complex with Hg2+ demonstrate a significant tendency to enter and accumulate in cells even at very low concentrations. [ABSTRACT FROM AUTHOR]

Mill scale (MS) is considered to be a significant metallurgical waste, but there is no economical method yet to utilize its metal content. In this study, which covers various processes in several stages, the solution of iron in MS, which is the Iron and Steel Industry (I&SI) waste, as FeCl3 (MS-FeCl3) in the thermoreactor in the presence of HCl, was investigated. In the next step, the conditions for using this solution as a coagulant in the treatment of I&SI wastewater were investigated using the jar test. The results of the treated water sample were compared by chemical oxygen demand (COD), total suspended solids (TSS), color, and turbidity analyses using commercial aluminum sulfate (Al2(SO4)3) and FeCl3 (C-FeCl3). Additionally, heavy metal analyses were conducted, and the treatment performance of three coagulants was presented. Accordingly, while 2.0 mg/L anionic polyelectrolyte was consumed at a dosage of 4.05 mg/L Al2(SO4)3 at pH 7.0, 0.25 mg/L anionic polyelectrolyte was consumed at a dosage of 1.29 mg/L at pH 5.0 in the C-FeCl3 and MS-FeCl3 studies. Also, Fe, Cr, Mn, Ni, Zn, Cd, Hg, and Pb removal efficiencies were over 93.56% for all three coagulant usage cases. The results showed that the wastewater treatment performance of MS-FeCl3 by the recycling of MS, which is an I&SI waste, was at the same level as C-FeCl3. Thus, thanks to recycling, waste scale can be used as an alternative to commercial products for green production. [ABSTRACT FROM AUTHOR]

Toxicological effects of silver nanoparticles (SNPs) in different organisms have been studied; however, interactions of SNPs with other environmental pollutants such as mercury are poorly understood. Herein, bioassay tests were performed according to ΟECD 201 guideline to assess the toxic effects induced by mercury ions (mercury chloride, MCl) on the marine microalga Chaetoceros muelleri in the presence of SNPs or silver ions (silver nitrate, SN). Acute toxicity tests displayed that the presence of SNPs or SN (0.01 mg L−1) significantly reduced the toxicity of MCl (0.001, 0.01, 0.1, 1, 10, and 100 mg L−1) and increased the IC50 of MCl from 0.072 ± 0.014 to 0.381 ± 0.029 and 0.676 ± 0.034 mg L−1, respectively. In the presence of SN or SNPs, the mercury-reducing effect on algal population growth significantly decreased. Considering the increase of IC50, the mercury toxicity decreased approximately 5.44 and 9.66 times in the presence of SNPs or SN, respectively. The chlorophyll a and c contents decreased at all exposures; however, the decrease by MCl-SNPs and MCl-SN was significantly less than MCl except at 1 mg L−1. The lowering effect of MCl-SN on chlorophyll contents was less than MCl and MCl-SNPs. MCl exposure induced significant raises in total protein content (TPC) at concentrations < 0.01mg L−1, with a maximum of ~ 70.83% attained at 100 mg L−1. The effects of MCl-SNPs and MCl-SN on TPC were significantly less than MCl. Total lipid content (TLC) at all MCl concentrations was higher than the control, while at coexposure to MCl-SN, TLC did not change until 0.01 mg L−1 compared with the control. The effects of MCl-SN and MCL-SNPs on TPC and TLC were in line with toxicity results, and were significantly less than those of MCl individually, confirming their antagonistic effects on MCl. The morphological changes of algal cells and mercury content of the cell wall at MCl-SN and MCl-SNPs were mitigated compared with MCl exposure. These findings highlight the mitigatory impacts of silver species on mercury toxicity, emphasizing the need for better realizing the mixture toxicity effects of pollutants in the water ecosystem. [ABSTRACT FROM AUTHOR]

The high toxicity of mercury (Hg) poses a danger to the environment and humans, but studies of the concentration of this metal in organisms of terrestrial ecosystems are few. Ecotoxicologists also pay little attention to studying the role of antioxidant vitamins in protecting cells from toxic metals. The Republic of Karelia is one of the northwestern regions of Russia, the biogeochemical features of which can contribute to an increase in the mobility and bioavailability of Hg in food chains. The purpose of the work was to determine the concentration of Hg in the liver, kidneys, muscle and hair of ungulate mammals of the Republic of Karelia (wild boar Sus scrofa L. and moose Alces alces L.) and to analyze the relationship between the level of this toxic metal and the content of low molecular-weight antioxidants—reduced glutathione, retinol and α-tocopherol. Species and tissue-specific of the studied parameters in wild boars and moose are noted. The observations discovered by other researchers that omnivorous species accumulate more Hg in their tissues compared to herbivores, and also that this toxic metal is predominantly accumulated in the kidneys, while muscles contain a minimal amount, have been confirmed. Hg concentrations in most samples of liver and kidney of wild boars and in all samples of the same organs of moose were within the limits recorded for domestic pigs and deer, respectively. The levels of Hg we recorded in the tissues and hair of wild boars and moose were generally comparable to or lower than the levels of this metal noted in animals from other regions of Russia and other countries of the world. In wild boars and moose of Karelia, no statistically significant relationships were found between the Hg level and the content of the studied antioxidants in the internal organs. Moose were characterized by a higher content of α-tocopherol in the body than wild boars, which is a feature of this type of herbivorous ungulate mammal. The results of the study indicate a relatively low level of mercury pollution in terrestrial ecosystems in Karelia. [ABSTRACT FROM AUTHOR]

Acute and chronic exposure of heavy metals exerts detrimental effect at the cellular level and is a rising global concern. The pollutants once introduced in the water bodies, subsequently enters the food chain, and poses risks not only to the aquatic organisms, but to the human consumers as well. Therefore, understanding the toxicological level of these metals is vital for assessing the severity of potential risks. The study aimed to conduct a comparative analysis of the acute toxicity of mercury and cadmium on Channa punctatus through a 96-hour bioassay. It was carried out in a semi-static laboratory condition following the standard guidelines. The behavioural, and mortality response was recorded at the 24, 48, 72, and 96 h of exposure duration for both toxicants. The results demonstrated distinct differences in toxicity levels between mercury and cadmium. The 96h-LC50 value for cadmium was measured at 6.19 mg/l, while for mercury, it was significantly lower at 0.44 mg/l. It was revealed that even the trace concentration of metals can induce toxicity, if given for a prolonged period of time. Furthermore, the study observed heightened toxicity of mercury, exerting adverse effects at lower concentrations compared to cadmium within the same exposure duration. [ABSTRACT FROM AUTHOR]

Mercury (Hg) pollution is a global public health concern because of its adverse effects on the environment and health. Single-nucleotide polymorphisms (SNPs) have been associated with Hg levels and outcomes. The aim of this review was to describe the research and discuss the evidence on the genetic susceptibility of Hg-exposed individuals to the development of neurocognitive disorders. A systematic review was performed to identify the genes/SNPs associated with Hg toxicokinetics and that, therefore, affect neurological function in exposed populations. Observational and experimental studies were identified by screening three databases. Thirteen articles were included (quality score 82–100%) and 8124 individuals were evaluated. Hg exposure was mainly fish consumption (77%) and, in 31% of the studies, the Hg levels exceeded the reference limits. Genetic susceptibility to higher Hg levels and neurotoxicity risk in Hg poisoning were associated with eight (ALAD rs1800435, CYP3A4 rs2740574, CYP3A5 rs776746, CYP3A7 rs2257401, GSTP1 rs1695, MT1A rs8052394, MT1M rs2270836, and MT4 rs11643815) and three (MT1A rs8052394, MT1M rs2270837, and MT2A rs10636) SNPs, respectively, and rs8052394 was associated with both outcomes. The MT1A rs8052394 SNP may be used as a susceptibility biomarker to identify individuals at greater risk for higher Hg levels and the development of neurocognitive disorders in metal-exposed populations. [ABSTRACT FROM AUTHOR]

Widespread contamination of the Amazon basin with mercury has been reported to occur since at least the mid-80s due to heavy gold mining activity. Although initial studies have indicated that this may lead to deleterious neurological consequences to the indigenous populations living in the region, further research is needed to better characterize the neurological burden of such long-term exposure. With this aim, a cross-sectional exploratory study has been conducted with the Yanomami indigenous population residing in a northern Amazon region. All participants underwent a structured interview; detailed neurological examination, including assessment for cognitive, motor, coordination, and sensory functions; and laboratorial testing for serum hemoglobin, blood glucose, and methylmercury levels in hair samples. This study enrolled 154 individuals of 30.9 ± 16.8 years of age, of which 56.1% were female. Mean methylmercury levels in hair were 3.9 ± 1.7 µg/g. Methylmercury levels in hair > 6.0 µg/g were found in 10.3%. Among participants with hair methylmercury levels ≥ 6.0 μg/g, the prevalences of peripheral neuropathy and reduced cognitive performance were, respectively, 78.8% (95%CI 15–177%, p = 0.010) and 95.9% (95%CI 16–230.8%, p = 0.012) higher than those of individuals with lower levels. These results suggest that chronic mercury exposure may lead to significant and potentially irreversible neurotoxicity to Yanomami population living in the northern Amazon basin. [ABSTRACT FROM AUTHOR]

Background: Since the introduction of amalgam for tooth fillings, there have been concerns that mercury toxicity could pose unacceptable health risks. Rasa shastra is an ancient medical discipline that focuses on the utilization of metals and minerals for the treatment of diseases. Nevertheless, these minerals cannot be directly administered to the human body in their natural state due to their potential adverse effects. Hence, for medicinal purposes, these metals and minerals need to undergo purification (Shodhana) to eliminate impurities and modify their physical, chemical, and biological characteristics. Methodology: Human gingival fibroblasts (HGF) were exposed to commercially available mercury (CAHg) and ayurvedically purified mercury (AP-Hg) at concentrations of 6.25 μM, 12.5 μM, 25 μM and 50 μM. The unexposed HGF cultured in basal media was considered a control. All the samples were cultured for 24 hours and 48 hours, and the cytotoxicity was analyzed by MTT assay. Results: Cell viability between the control and experimental groups varied at 24 hours, however, the results were not statistically significant (p>0.05). At 48 hours, cell viability was higher in the AP-Hg group as compared to the CA-Hg group at the concentration of 6.25 μM, and the difference was statistically significant (p<0.05). The cell proliferation assay results demonstrated a statistically significant difference in the mean optical density values (p<0.05) between CA-Hg and AP-Hg at 12.50 μM, 25 μM, and 50, μM concentrations observed at 24 hours. At 48 hours, a statistically significant difference in the mean OD values (p<0.05) between CA-Hg and AP-Hg at all four concentrations was observed. Conclusion: AP-Hg at a concentration of 6.25 μM demonstrated higher cell viability at 48 hours. Further, the cell proliferation rate was also higher for AP-Hg at all concentrations at 24 and 48 hours. These results indicated a less cytotoxic effect of AP-Hg than CA-Hg in HGF and hence could be employed for dental amalgam preparations. [ABSTRACT FROM AUTHOR]

A 64-year-old man had progressive unsteadiness over several years, with tingling in his feet. He was a longstanding bodybuilding enthusiast. Clinical assessment and neurophysiology confirmed a cerebellar ataxia and axonal peripheral neuropathy. His serum mercury concentration was significantly raised. We diagnosed chronic mercury toxicity secondary to excessive tuna consumption. We advised him to stop eating tuna and prescribed dimercaptosuccinic acid, after which his serum mercury concentrations subsequently fell. This case report highlights the importance of considering dietary and nutritional causes of neurological disease. We also discuss the mechanisms, diagnosis and treatment of mercury toxicity. [ABSTRACT FROM AUTHOR]

Several types of pollutants have acute adverse effects on living bodies, and the effective removal of these pollutants remains a challenge. Safranin O (a biological dye) and merbromin (a topical mercury-containing antiseptic) are considered organic pollutants, and there are only a few reports on their removal. Synthesized and well-characterized (through PXRD, FTIR, FESEM, and EDS analysis) MOF-5 was used for the first time in the removal of safranin O and merbromin from simulated wastewater and real wastewater. In both cases, MOF-5 effectively removed contaminants. We found that in simulated wastewater, the highest efficiency of removal of safranin O was 53.27% (for 15 mg/L) at pH 10, and for merbromin, it was 41.49% (for 25 mg/L) at pH 6. In the case of real wastewater containing natural ions (Na+, K+, F−, Cl−, SO42−, PO43−, Mg2+, and Ca2+) and other molecules, the removal efficiencies of these two dyes decreased (34.00% and 26.28% for safranin O and merbromin, respectively) because of the presence of other ions and molecules. A plausible mechanism for the removal of these pollutants using MOF-5 was proposed. [ABSTRACT FROM AUTHOR]