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Abstract Heavy metals are encountered in nature, and are used in several human endeavors, including in dental fillings. It is well known that the safety of metals depends on their chemical form, as well as the dose and route through which biological systems are exposed to them. Here, we used the Nauphoeta cinerea model to examine the mechanism by which salts of the heavy metals used in dental fillings – silver and mercury – exert their neurotoxicity. Nymphs exposed to heavy metals presented with reduced motor and exploratory abilities as they spent more time immobile, especially in the periphery of a novel object, and covered less distance compared with control nymphs. Exposure to AgNO3 and HgCl2 also exacerbated levels of oxidative stress markers (MDA & ROS) and the neurotransmitter regulators – AChE and MAO, while reducing antioxidant activity markers, both in biochemical (thiol & GST) and RT-qPCR (TRX, GST, SOD, Catalase) examinations, in neural tissues of the cockroach. The observed disruptions in neurolocomotor control, synaptic transmission and redox balance explain how heavy metal salts may predispose organisms to neurological disorders.

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]

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Fisher’s Exact Test test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Objectives: This study investigated the presence of mercury in commonly used over the counter skin-lightening creams available in Trinidad and Tobago. The objective of this study was to evaluate if skin-lightening creams commonly used in Trinidad and Tobago contained Mercury, and establish the health risks presented by these products. Methods: Nineteen skin-lightening creams were analysed using Cold Capor Atomic Absorption Spectrophotometry (CV-AAS). Margin of Safety (MoS) and Hazard Quotient (HQ) calculations were used to assess risk to users. Results: Of the nineteen creams assessed, sixteen contained high concentrations of mercury (0.294-14414.5 μg/g), only three creams had no mercury detected. 9 of the 19 samples contained levels of mercury that exceed the Minamata convention's accepted limit of 1μg/g, with 3 samples exceeding 3800.000 μg/g. Risk assessments using MoS and HQ showed that 3 of the samples were unsafe for use and are considered hazardous. The study also revealed that many creams do contain mercury even if it did not constitute part of the product formulation. Conclusion: The data infers that some manufacturers do add mercury to their formulations while others are the victims of contaminated raw materials. MoS and HQ show that 21% of the samples were unsafe and 16% can be considered hazardous for human use. It is possible that with such levels of mercury in these products and the popularity of these products within the Caribbean Community and its diaspora, that there exists a significant amount of members with higher than acceptable mercury levels, with undiagnosed clinical symptoms. [ABSTRACT FROM AUTHOR]

The main entrance point of highly toxic organic Hg forms, including methylmercury (MeHg), into the aquatic food web is phytoplankton, which is greatly represented by various natural microalgal species. Processes associated with MeHg fate in microalgae cells such as uptake, effects on cells and toxicity, Hg biotransformation, and intracellular stability are detrimental to the process of further biomagnification and, as a consequence, have great importance for human health. The study of MeHg uptake and distribution in cultures of marine halophile Dunaliella salina and freshwater acidophilic alga Coccomyxa onubensis demonstrated that most of the MeHg is imported inside the cell, while cell surface adhesion is insignificant. Almost all MeHg is removed from the culture medium after 72 h. Significant processes in rapid MeHg removal from liquid medium are its abiotic photodegradation and volatilization associated with algal enzymatic activity. The maximum intracellular accumulation for both species was in 80 nM MeHg-exposed cultures after 24 h of exposure for D. salina (from 27 to 34 µg/gDW) and at 48 h for C. onubensis (up to 138 µg/gDW). The different Hg intakes in these two strains could be explained by the lack of a rigid cell wall in D. salina and the higher chemical ability of MeHg to pass through complex cell wall structures in C. onubensis. Electron microscopy studies on the ultrastructure of both strains demonstrated obvious microvacuolization in the form of many very small vacuoles and partial cell membrane disruption in 80 nM MeHg-exposed cultures. Results further showed that Coccomyxa onubensis is a good candidate for MeHg-contaminated water reclamation due to its great robustness at nanomolar concentrations of MeHg coupled with its very high intake and almost complete Hg removal from liquid medium at the MeHg levels tested. [ABSTRACT FROM AUTHOR]

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Fisher’s Exact Test test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Chi-square test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

The toxic metal mercury (Hg) exhibits inhibitory effects on several plant physiological processes. Multiple attempts have been tried in the past to lessen the phytotoxic effects of Hg in plants. However, so far no information is available on the possible beneficial effects of magnetopriming in soybean plants subjected to Hg toxicity. In the present study, the soybean seeds were magnetoprimed by static magnetic field (SMF) of 200 mT for 1 h to assess the influence of magnetopriming on germination and early growth features of seedlings under Hg toxicity. Reduction in germination percentage and growth parameters such as seedling length, fresh and dry weight of seedlings and vigor indices of seedlings emerged from unprimed seeds under different concentrations of mercuric chloride (0.0, 0.05, 0.1 mM HgCl2), indicated the negative effects of Hg toxicity on seedling growth at all the concentrations of HgCl2. However, magnetopriming has been found to be effective in alleviating the Hg stress. Along with hydrogen peroxide (H2O2) and nitric oxide (NO), the activities of total amylase, protease, and nitrate reductase (NR) were elevated in seedlings emerged from SMF-primed seeds in non-stress as well as Hg toxicity conditions. The proline and malondialdehyde (MDA) contents were increased with the increasing Hg concentrations in the seedlings emerged from unprimed seeds; however, magnetopriming reduced their content. Antioxidant enzyme system revealed higher activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GuPOX) along with higher antioxidants (total ascorbate, AsA and reduced glutathione, GSH content) after SMF priming in comparison to unprimed seeds during germination at all the concentrations of HgCl2 used. It is conceivable that the positive effect of magnetopriming is mediated by the reduced lipid peroxidation and enhancement of H2O2 and NO levels along with the activation of antioxidant defense system to protect the soybean seedlings against Hg toxicity during seed germination. [ABSTRACT FROM AUTHOR]

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Many organizations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. The percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analyzed using Students-t test and Chi-square test. Results Most dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions Despite satisfaction with DA for its minimal failure, longevity and affordability, the authors found that most practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Heavy metal exposure leads to multiple system dysfunctions. The mechanisms are likely multifactorial and involve inflammation and oxidative stress. The aim of this study was to evaluate markers and risk factors for atherosclerosis in the LDL receptor knockout mouse model chronically exposed to inorganic mercury (Hg) in the drinking water. Results revealed that Hg exposed mice present increased plasma levels of cholesterol, without alterations in glucose. As a major source and target of oxidants, we evaluated mitochondrial function. We found that liver mitochondria from Hg treated mice show worse respiratory control, lower oxidative phosphorylation efficiency and increased H2O2 release. In addition, Hg induced mitochondrial membrane permeability transition. Erythrocytes from Hg treated mice showed a 50% reduction in their ability to take up oxygen, lower levels of reduced glutathione (GSH) and of antioxidant enzymes (SOD, catalase and GPx). The Hg treatment disturbed immune system cells counting and function. While lymphocytes were reduced, monocytes, eosinophils and neutrophils were increased. Peritoneal macrophages from Hg treated mice showed increased phagocytic activity. Hg exposed mice tissues present metal impregnation and parenchymal architecture alterations. In agreement, increased systemic markers of liver and kidney dysfunction were observed. Plasma, liver and kidney oxidative damage indicators (MDA and carbonyl) were increased while GSH and thiol groups were diminished by Hg exposure. Importantly, atherosclerotic lesion size in the aorta root of Hg exposed mice were larger than in controls. In conclusion, in vivo chronic exposure to Hg worsens the hypercholesterolemia, impairs mitochondrial bioenergetics and redox function, alters immune cells profile and function, causes several tissues oxidative damage and accelerates atherosclerosis development.

Background For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Yet, many organisations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. Percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analysed using Students-t test and Chi-square test. Results The majority of dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions In spite of satisfaction with DA for its minimal failure, longevity and affordability, the authors found that a majority of practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Mercury has been described as been in daily household items such as soaps, skin-lightening creams (SLC), and topical disinfectants. Mercury exposure can reportedly cause damage to the optic nerve and retina. A 30-year-old Somali woman presented with decreased vision and was found to have bilateral optic atrophy. Neuroimaging and laboratory work-up for nutritional deficiencies, heavy metals, and syphilis were performed. Evaluation revealed normal neuroimaging and laboratory work-up except for elevated serum and urine mercury levels. Mercury levels at the initial blood test was 11.1 ug/L (normal limits < 10.0 ug/L) and was 15.7 ug/L on repeat testing. A 24-h urine test showed elevated mercury at 16 ug/24 h (normal limits < 2 ug/24 h). Evaluation of an unlabelled SLC that she was using showed the presence of mercury. It is worth testing for heavy metals in the work-up of bilateral optic atrophy. Clinicians should consider cosmetic products as a potential source of mercury exposure and recommend discontinuation if mercury is present. [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]

In several cultures, black cumin, also known as Nigella sativa, has long been used medicinally. Recent research has revealed that this plant has potent anti-inflammatory and antioxidant qualities, making it a possible treatment for several medical conditions. Additionally, because of its capacity to detoxify the liver and protect it from harm, Nigella sativa has demonstrated positive results as an antidote for poisoning. Consumption of hazardous substances by accident or planned poisoning are two prevalent causes of poisoning. The liver is the primary organ in detoxification. According to studies, Nigella sativa can help the liver operate better and defend it from toxins' harmful effects. Additionally, it has been demonstrated that Nigella sativa protects against heavy metal toxicity. Thymoquinone and thymohydroquinone, the plant's active components, have been demonstrated to bond with heavy metals and stop the body from absorbing them. Further studies are needed to evaluate the efficacy and safety of Nigella sativa as an antidote for poisoning cases. Nigella sativa presents an interesting natural alternative for treating poisoning cases, potentially complementing traditional medical approaches. The main goal of this review is to explore the potential application of Nigella sativa as an antidote for poisoning cases. The article discusses the plant's strong ability to detoxify and protect the liver. The review highlights preclinical studies that have shown promising results but also emphasizes the need for further clinical trials to determine the efficacy and safety of Nigella sativa as a natural alternative for treating poisoning cases. [ABSTRACT FROM AUTHOR]

Purpose The popularity of dental amalgam arises from its excellent long-term performance, ease of use, and low cost. However, there is a concern about the potential adverse health effects arising from exposure to mercury in amalgam. This review article critically discusses the safety of dental amalgam as a restorative material and our preparedness for a mercury-free road ahead. Materials and Methods A database search was performed on PubMed and Google scholar using the keywords: "mercury-free dentistry", "mercury toxicity", "amalgam substitutes", "amalgam mercury toxicity". Inclusion and exclusion criteria were specified clearly. Relevant literature was also searched in the dental textbooks. Results Around 40 articles, highlighting mercury exposure among dental professionals and patients were included. Despite the overwhelming body of scientific evidence demonstrating amalgam to be a safe restorative material, concerns about the toxic effects of mercury persist. Conclusion The real challenge is to find a suitable amalgam substitute and to follow the mercury hygiene measures closely. [ABSTRACT FROM AUTHOR]

The main entrance point of highly toxic organic Hg forms, including methylmercury (MeHg), into the aquatic food web is phytoplankton, which is greatly represented by various natural microalgal species. Processes associated with MeHg fate in microalgae cells such as uptake, effects on cells and toxicity, Hg biotransformation, and intracellular stability are detrimental to the process of further biomagnification and, as a consequence, have great importance for human health. The study of MeHg uptake and distribution in cultures of marine halophile Dunaliella salina and freshwater acidophilic alga Coccomyxa onubensis demonstrated that most of the MeHg is imported inside the cell, while cell surface adhesion is insignificant. Almost all MeHg is removed from the culture medium after 72 h. Significant processes in rapid MeHg removal from liquid medium are its abiotic photodegradation and volatilization associated with algal enzymatic activity. The maximum intracellular accumulation for both species was in 80 nM MeHg-exposed cultures after 24 h of exposure for D. salina (from 27 to 34 µg/gDW) and at 48 h for C. onubensis (up to 138 µg/gDW). The different Hg intakes in these two strains could be explained by the lack of a rigid cell wall in D. salina and the higher chemical ability of MeHg to pass through complex cell wall structures in C. onubensis. Electron microscopy studies on the ultrastructure of both strains demonstrated obvious microvacuolization in the form of many very small vacuoles and partial cell membrane disruption in 80 nM MeHg-exposed cultures. Results further showed that Coccomyxa onubensis is a good candidate for MeHg-contaminated water reclamation due to its great robustness at nanomolar concentrations of MeHg coupled with its very high intake and almost complete Hg removal from liquid medium at the MeHg levels tested.

In nature, thiolate‐based systems are the primary targets of divalent mercury (HgII) toxicity. The formation of Hg(Cys)x cores in catalytic and structural protein centers mediates mercury's toxic effects and ultimately leads to cellular damage. Multiple studies have revealed distinct HgII‐thiolate coordination preferences, among which linear HgII complexes are the most commonly observed in solution at physiological pH. Trigonal or tetrahedral geometries are formed at basic pH or in tight intraprotein Cys‐rich metal sites. So far, no interprotein tetrahedral HgII complex formed at neutral pH has been reported. Rad50 protein is a part of the multiprotein MRN complex, a major player in DNA damage‐repair processes. Its central region consists of a conserved CXXC motif that enables dimerization of two Rad50 molecules by coordinating ZnII. Dimerized motifs form a unique interprotein zinc hook domain (Hk) that is critical for the biological activity of the MRN. Using a series of length‐differentiated peptide models of the Pyrococcus furiosus zinc hook domain, we investigated its interaction with HgII. Using UV‐Vis, CD, PAC, and 199Hg NMR spectroscopies as well as anisotropy decay, we discovered that all Rad50 fragments preferentially form homodimeric Hg(Hk)2 species with a distorted tetrahedral HgS4 coordination environment at physiological pH; this is the first example of an interprotein mercury site displaying tetrahedral geometry in solution. At higher HgII content, monomeric HgHk complexes with linear geometry are formed. The Hg(Cys)4 core of Rad50 is extremely stable and does not compete with cyanides, NAC, or DTT. Applying ITC, we found that the stability constant of the Rad50 Hg(Hk)2 complex is approximately three orders of magnitude higher than those of the strongest HgII complexes known to date. [ABSTRACT FROM AUTHOR]

Background: For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Yet, many organisations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods: This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. Percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analysed using Students-t test and Chi-square test. Results: The majority of dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions: In spite of satisfaction with DA for its minimal failure, longevity and affordability, the authors found that a majority of practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

Background: For more than 150 years, dental amalgam (DA) has been popular as a dental restorative material. Yet, many organisations oppose its use due to perceived toxicity and environmental concerns. Hence, this study aimed to explore the continued use of DA from a South Indian dental practitioners’ perspective. Methods: This cross-sectional study was conducted among fifty-two private and public dental practitioners of Udupi district in Southern India. A self‑administered questionnaire was distributed, that involved assessment of their preferences, continuation of use and concerns of using DA as a restorative material. Percentage contribution of each variable was calculated. Preferences for continuation of use of silver amalgam based upon the age, experience and mercury toxicity as a risk factor were analysed using Students-t test and Chi-square test. Results: The majority of dentists were satisfied (87%) with the results of the DA, found minimal failures (96%) and found DA more economical (89%). More than half (54%) of the participants reported that they would not continue the use of DA owing to mercury toxicity and environmental concerns. Dentists with higher age and longer clinical experience preferred continuation of DA. Conclusions: In spite of satisfaction with DA for its minimal failure, longevity and affordability, the authors found that a majority of practitioners did not prefer its continued usage. This highlights their concerns over mercury toxicity and soft tissue lesions and accentuates their community social responsibility. There is also an urgent need to educate dentists on mercury hygiene, mercury waste management and disposal.

There has been a serious health and environmental concern in conversion of inorganic mercury (Hg) to the neurotoxin, methylmercury (MeHg) by anaerobic microbes, while very little is known about the potential role of vitamin B9 (VB9) regulator in the biochemical generation of MeHg. This study innovatively investigated bacterial Hg methylation by Geobacter sulfurreducens PCA in the presence of VB9 under two existing scenarios. In the low-complexing scenario, the bacterial MeHg yield reached 68 % higher than that without VB9 within 72 h, which was attributed to free VB9-protected PCA cells relieving oxidative stress, as manifested by the increased expression of Hg methylation gene (hgcAB cluster by 19-48 %). The high-complexing scenario emphasized the intracellular Hg accumulation (38-45 %) after 12 h, as indicated by the increased expression of outer membrane protein-related and mercuric reductase-encoding genes, indicating the inefficient bioavailability of Hg due to a gradual shift from Hg reduction toward Hg 0 re-oxidation controlled by competitive ligand exchange. These results suggested that VB9 application significantly raised the potential for bacterial Hg methylation and cellular accumulation, thus proposing insights into the biochemical behaviors of hazardous Hg in farming environments where vulnerable organisms are more possibly co-exposed to higher levels of Hg and VB9., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Heavy metals are harmful environmental pollutants that have attracted widespread attention, attributed to their health hazards to humans and animals. Due to the non-degradable property of heavy metals, organisms are inevitably exposed to heavy metals such as arsenic (As), cadmium (Cd), lead (Pb), and mercury (Hg). Several studies revealed that heavy metals can cause reproductive damage by the excessive production of reactive oxygen species (ROS), which exacerbates oxidative stress, inflammation, and endocrine disruption. Natural antioxidants, mainly polyphenols, carotenoids, and vitamins, have been shown to mitigate heavy metal-induced reproductive toxicity potentially. In this review, accumulated evidences on the influences of four non-essential heavy metals As, Cd, Pb, and Hg on both males and females reproductive system were established. The purpose of this review is to explore the potential mechanisms of the effects of heavy metals on reproductive function and point out the potential biomarkers of natural antioxidants interventions toward heavy metal-induced reproductive toxicity. Notably, increasing evidence proven that the regulations of hypothalamic-pituitary-gonadal axis, Nrf2, MAPK, or NF-κB pathways are the important mechanisms for the amelioration of heavy metal induced reproductive toxicity by natural antioxidants. It also provided a promising guidance for prevention and management of heavy metal-induced reproductive toxicity.

Strain SAICEUPBM T was isolated from soils of Almadén (Ciudad Real, Spain), subjected to a high mercury concentration. SAICEUPBM T significantly increased aerial plant weight, aerial plant length and the development of secondary roots under mercury stress; increased twice the absorption of mercury by the plant, while favoring its development in terms of biomass. Similarly, plants inoculated with SAICEUPBM T and grown in soils contaminated with mercury, express a lower activity of antioxidant enzymes; catalase enzymes (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR) for defense against ROS (reactive oxygen species). Whole genome analysis showed that ANI (95. 96 %), dDDH (72.9 %), AAI (93.3 %) and TETRA (0.99) values were on the thresholds established for differentiation a subspecies. The fatty acids analysis related the strain with the Peribacillus frigoritolerans species. And the synapomorphic analysis reveals a common ancestor with analysis related the strain with the Peribacillus frigoritolerans species. Results from genomic analysis together with differences in phenotypic features and chemotaxonomic analysis support the proposal of strain SAICEUPBM T as the type strain of a novel subspecies for which the name Peribacillus frigoritolerans subps. mercuritolerans sp. nov is proposed. The absence of virulence genes and transmissible resistance mechanisms reveals its safety for agronomic uses, under mercury stress conditions. The ability of Peribacillus frigoritolerans subsp. mercuritolerans subsp. nov to improve plant development was tested in a Lupinus albus model, demonstrating a great potential for plant phytoprotection against mercury stress., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Twenty-eight beekeepers around Slovakia were included in the research to evaluate the presence of mercury in honeybee bodies and selected bee-related products: bee pollen and honey. The samples were collected in May, June, and July (honeybee bodies only in May and June). During this period, moss and lichen bags for air quality assessment were exposed around the beehives and relative accumulation factor (RAF) was used for its evaluation. Mercury content in evaluated bioindicators was determined using AMA 254 analyser. Percentage of provisional tolerable intake (%PTWI) and target hazard quotient (THQ) were used to determine health risks related to bee pollen and honey consumption. Around the beehives the proportion of landscape structure elements was determined for each sampling locality, using a geographical informational system QGIS. The aim of the study was a comprehensive evaluation of the mercury content in the environment around beehives using several bioindicators and an assessment of the relationship between the presence of mercury pollution and the proportion of landscape structure elements in the vicinity of the beehives. The study also aimed to evaluate the transfer of contaminants between bee bodies and bee-related products and the health risks resulting from their consumption., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

This study analyzes the activities, poisoning, and medical treatment of the "La Esperanza" mercury mine workers in Aranzazu (Caldas, Colombia) between 1948 and 1975. The mining work there was difficult due to the geological instability of the area and the use of inappropriate mining technology, which generated a high occurrence of poisoning manifested in tremors of limbs, bleeding gums, loss of teeth, and bad mouth odor. The mine was the first Colombian company to treat its poisoned workers with dimercaprol and penicillamine. Occupational toxicology in Colombia was thus born during one of the most significant occupational health disasters in the country.

Here, we subjected the marine copepod Tigriopus japonicus to environmentally-relevant concentrations of microplastics (MPs) and mercury (Hg) for three generations (F0-F2) to investigate their physiological and molecular responses. Hg accumulation and phenotypic traits were measured in each generation, with multi-omics analysis conducted in F2. The results showed that MPs insignificantly impacted the copepod's development and reproduction, however, which were significantly compromised by Hg exposure. Interestingly, MPs significantly increased Hg accumulation and consequently aggravated this metal toxicity in T. japonicus, demonstrating their carrier role. Multi-omics analysis indicated that Hg pollution produced numerous toxic events, e.g., induction of apoptosis, damage to cell/organ morphogenesis, and disordered energy metabolism, ultimately resulting in retarded development and decreased fecundity. Importantly, MPs enhanced Hg toxicity mainly via increased oxidative apoptosis, compromised cell/organ morphogenesis, and energy depletion. Additionally, phosphoproteomic analysis revealed extensive regulation of the above processes, and also impaired neuron activity under combined MPs and Hg exposure. These alterations adversely affected development and reproduction of T. japonicus. Overall, our findings should offer novel molecular insights into the response of T. japonicus to long-term exposure to MPs and Hg, with a particular emphasis on the carrier role of MPs on Hg toxicity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The presence of heavy metals in food products may seem an archaic concern; however, our study reveals that the risk is significant, unexpectedly in Food for Special Medical Purposes (FSMP) for oncology patients available in Polish pharmacies. This investigation fills that gap through a detailed toxicological analysis and health risk assessment of these heavy metals in FSMP products (n = 23) using inductively coupled plasma mass spectrometry (ICP-MS). Our comprehensive risk assessment involved evaluating (1) the concentrations of As, Cd, Hg, and Pb in both liquid and powdered FSMP formulations, (2) the amount of heavy metals ingested per serving as specified by the manufacturer, and (3) the cumulative daily and weekly intake adjusted for body weight, benchmarked against the provisional tolerable weekly intake (PTWI). While most samples were below PTWI limits, Cd levels raised concerns due to potential cumulative exposure risks, particularly for oncology patients consuming these products regularly. This study underscores the hidden dangers of heavy metal contamination in FSMP, emphasizing the need for vigilant monitoring and stringent regulatory frameworks to ensure patient safety. By uncovering these latent risks through meticulous toxicological assessment, our research provides crucial insights that could safeguard vulnerable populations. This study is significant due to concerns related to the complex risk assessment of FSMP for cancer patients, considering the complexity of oncological diseases and other comorbid factors, as well as the verification of available legal and regulatory acts of FSMP at the European Community level., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Mercury (Hg) is a persistent soil pollutant, and its toxicity can be evaluated using soil enzyme indicators. However, a thorough understanding of how the enzyme resists and remains resilient to Hg stress is essential, as it significantly impacts the accuracy of toxicity assessments. Therefore, it is worthwhile to understand the functional stability of urease in soil under Hg pollution. This study compares the effects of Hg at different concentrations and exposure times on soil urease. Results indicate that soil urease activity was enhanced in the first two hours under low levels of Hg pollution, decreased after six hours of acute Hg pollution, and reached its maximum reduction in 24 hours. The urease in fluvo-aquic soil, with higher soil organic matter showed higher resistance to Hg acute pollution than that in red soil. Over a longer aging process, soil urease activity gradually recovered with time. Hormesis effects were observed in red soil under high Hg stress after 30 days, showing the strong resilience of urease enzyme function to Hg pollution. The ecological dose, ED 10 , (the Hg concentration causing a 10% reduction in soil urease activity) ranged from 0.09 to 0.59 mg kg -1 under short-term exposure, and was lower than that under a longer aging process (0.28 to 2.71 mg kg -1 ). Further, aging reduced the Hg ecotoxicity due to decreased Hg availability and the resilience of soil urease activity. This indicates that the risk of Hg pollution estimated by soil urease as an indicator depends on exposure time and enzyme stability. These factors need consideration in heavy metal pollution assessments using soil enzymes., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Emerging evidence suggests that plants experiencing abiotic stress actively seek help from soil microbes. However, the empirical evidence supporting this strategy is limited, especially in response to heavy metal stress. We used integrated microbial community profiling and culture-based methods to investigate the interaction between mercury (Hg) stress, the entophytic root microbiome, and maize seedlings. The results of the pot experiment showed that soil Hg (20 mg/kg) strongly inhibited maize growth, indicating its strong phytotoxicity. Furthermore, Hg stress significantly altered the structure of the bacterial and fungal communities and enriched the potentially pathogenic Fusarium sp., suggesting that soil Hg stress may enhance the bio-stress induced by Fusarium species in maize. Additionally, soil Hg also led to the enrichment of beneficial bacterial members of Streptomyces, Lysobacter, and Sphingomonas (defined as differential species), which were also identified as keystone species in the Hg treatment by the analysis of co-occurrence networks. Therefore, it can be postulated that the members of Streptomyces, Lysobacter, and Sphingomonas function as stress-alleviating microbes. We successfully isolated the representatives of these stress-alleviating microbes. As expected, these strains mitigated the detrimental effects of Hg stess for the maize seedlings, suggesting that plants recruit the stress-alleviated microbiota to combat Hg stress. This study provides insights into the potential of manipulating the root microbiome to enhance plant growth in polluted environments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Tributyltin (TBT) and mercury (Hg) are endocrine-disrupting chemicals that individually cause reproductive complications. However, the reproductive consequences of exposure to a mixture of TBT plus Hg are not well known. We hypothesized that exposure to a mixture of TBT plus Hg would alter hypothalamic-pituitary-gonadal (HPG) axis function. Female rats were exposed to this mixture daily for 15 days, after which chemical accumulation in the tissues, morphology, hormone levels, inflammation, fibrosis, and protein expression in the reproductive organs were assessed. Increases in tin (Sn) and Hg levels were detected in the serum, HPG axis, and uterus of TBT-Hg rats. TBT-Hg rats exhibited irregular estrous cycles. TBT-Hg rats showed an increase in gonadotropin-releasing hormone (GnRH) protein expression and follicle-stimulating hormone (FSH) levels and a reduction in luteinizing hormone (LH) levels. Reduced ovarian reserve, antral follicles, corpora lutea (CL) number, and estrogen levels and increased atretic and cystic follicles were found, suggesting that TBT-Hg exposure exacerbated premature ovarian insufficiency (POI) features. Furthermore, TBT-Hg rats exhibited increased ovarian mast cell numbers, expression of the inflammatory markers IL-6 and collagen deposition. Apoptosis and reduced gland number were observed in the uteri of TBT-Hg rats. A reduction in the number of pups/litter for 90 days was found in TBT-Hg rats, suggesting impaired fertility. Strong negative correlations were found between serum and ovarian Sn levels and ovarian Hg levels and ovarian reserve and CL number. Collectively, these data suggest that TBT plus Hg exposure leads to abnormalities in the HPG axis, exacerbating POI features and reducing fertility in female rats., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: We quantified the effect of acute exposure to a high dosage of inorganic mercury on gene expression in Drosophila melanogaster using RNA-sequencing of whole adult females., Results: We found 119 genes with higher gene expression following treatment (including all 5 Drosophila metallothionine genes and a number of heat shock protein genes), and 31 with lower expression (several of which are involved in egg formation). Our results highlight biological processes and genetic pathways impacted by exposure to this toxic metal, and provide motivation for future studies to understand the genetic basis of response to mercury., (© 2024. The Author(s).)

Environmental heavy metals pollution have seriously threatened the health of human beings. An increasing number of researches have demonstrated that environmental heavy metals can influence the telomere length of Peripheral Blood Mononuclear Cells (PBMCs), which implicate biological aging as well as predicts diseases. Our previous study has shown that methylmercury (MeHg)-induced telomere shortening in rat brain tissue was associated with urinary melatonin metabolite 6-sulfatoxymelatonin (aMT6s) levels. Here, we aimed to further elucidate the impact of 4 typical heavy metals (As, Hg, Cd and Pb) on telomere length of PBMCs and their association with urinary aMT6s in rats. In this study, eighty-eight male Sprague-Dawley rats were randomized grouped into eleven groups. Among them, forty 3-month-old (young) and forty 12-month-old (middle-aged) rats were divided into young or middle-aged control groups as well as typical heavy metals exposed groups, respectively. Eight 24-month-old rats (old) was divided into aging control group. The results showed that MeHg exposure in young rats while sodium arsenite (iAs), MeHg, cadmium chloride (CdCl 2 ), lead acetate (PbAc) exposure in middle-aged rats for 3 months significantly reduced the levels of and urinary aMT6s, as well as telomere length of PBMCs. In addition, they also induced abnormalities in serum oxidative stress (SOD, MDA and GPx) and inflammatory (IL-1β, IL-6 and TNF-α) indicators. Notably, there was a significant positive correlation between declined level of urinary aMT6s and the shortening of telomere length in PBMCs in rats exposed to 4 typical heavy metals. These results suggested that 4 typical heavy metals exposure could accelerate the reduction of telomere length of PBMCs partially by inducing oxidative stress and inflammatory in rats, while ageing may be an important synergistic factor. Urinary aMT6s detection may be a alternative method to reflect telomere toxic effects induced by heavy metal exposure., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Fifteen poplar varieties were used in a field trial to investigate the phytoremediation efficiency, stress resistance, and wood property of poplar hybrid varieties with diverse genetic backgrounds under the composite pollution of heavy metals. The coefficient of variation and clone repeatability for growth traits and Cd concentration were large. The Cd accumulation of poplar varieties 107 and QHQ reached 1.9 and 1.7 mg, respectively, followed by QHB, Ti, 69, and Pa, in which Cd accumulation reached 1.3 mg. Most of the intra-specific hybrid varieties (69, QH1, SL4, T3, and ZL46) had low Cd concentrations and small biomass, resulting in weak Cd accumulation and low phytoremediation efficiency for Cd-polluted soil. By contrast, the inter-sectional and inter-specific hybrid varieties exhibited better growth performance and accumulated higher concentrations of heavy metals than the intra-specific hybrids. The bioconcentration factor and translocation factor of Hg, As, and Pb were less than 1, indicating that poplars have low phytoremediation efficiency for these heavy metals. The hybrids between section Aigeiros and Tacamahaca (QHQ and QHB) and the inter-specific hybrid 107 within section Aigeiros were more resistant to composite heavy metal stress than the other poplar varieties were partially because of their high levels of free proline that exceeded 93 μg·g -1 FW. According to the correlation analysis of the concentrations of the different heavy metals, the poplar roots absorbed different heavy metals in a cooperative manner, indicating that elite poplar varieties with superior capacity for accumulating diverse heavy metals can be bred feasibly. Compared with the intra-specific hybrid varieties, the inter-sectional (QHQ and QHB) and inter-specific (107) hybrid varieties had higher pollution remediation efficiency, larger biomass, higher cellulose content, and lower lignin content, which is beneficial for pulpwood. Therefore, breeding and extending inter-sectional (QHQ and QHB) and inter-specific hybrid varieties can improve the phytoremediation of composite pollution., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Mercury is a well-known neurotoxicant for humans and wildlife. The epidemic of mercury poisoning in Japan has clearly demonstrated that chronic exposure to methylmercury (MeHg) results in serious neurological damage to the cerebral and cerebellar cortex, leading to the dysfunction of the central nervous system (CNS), especially in infants exposed to MeHg in utero. The occurrences of poisoning have caused a wide public concern regarding the health risk emanating from MeHg exposure; particularly those eating large amounts of fish may experience the low-level and long-term exposure. There is growing evidence that MeHg at environmentally relevant concentrations can affect the health of biota in the ecosystem. Although extensive in vivo and in vitro studies have demonstrated that the disruption of redox homeostasis and microtube assembly is mainly responsible for mercurial toxicity leading to adverse health outcomes, it is still unclear whether we could quantitively determine the occurrence of interaction between mercurial and thiols and/or selenols groups of proteins linked directly to outcomes, especially at very low levels of exposure. Furthermore, intracellular calcium homeostasis, cytoskeleton, mitochondrial function, oxidative stress, neurotransmitter release, and DNA methylation may be the targets of mercury compounds; however, the primary targets associated with the adverse outcomes remain to be elucidated. Considering these knowledge gaps, in this article, we conducted a comprehensive review of mercurial toxicity, focusing mainly on the mechanism, and genes/proteins expression. We speculated that comprehensive analyses of transcriptomics, proteomics, and metabolomics could enhance interpretation of "omics" profiles, which may reveal specific biomarkers obviously correlated with specific pathways that mediate selective neurotoxicity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Processing conditions applied during food production could affect food component contents and bioaccessibility. Here, possible changes in Hg and Se total and species contents and bioaccessibility have been tracked in each stage of the production chain of processed fish-derived products. Therefore, Se:Hg molar ratio and Selenium Health Benefit Value (HBV Se ) were calculated for final products and raw materials, resulting favorable in all cases, suggesting the safety of surimi-based products regarding mercury. Speciation studies revealed the presence of SeMeSeCys and SeMet in all samples. Thus, the integrity of the selenium species seems to be maintained. Moreover, in vitro gastrointestinal digestion model evidenced that Se bioaccessibility ranged between 20-39 % for all samples, while in case of Hg was between 8-37 %. Additionaly, SeMeSeCys and SeMet were also identified in the gastrointestinal extracts. Finally, no cytotoxicity was observed after exposure of Caco-2 cells to the gastrointestinal extracts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

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., (© 2024 International Society for Neurochemistry.)

The main route of human exposure to toxic contaminants is through the consumption of contaminated food. To protect against potential negative health effects of rice consumption, the concentration of total mercury (THg) in rice and rice products sold in Poland was determined, and a consumer risk assessment was carried out. In this study, the concentration of THg in selected types of rice and rice products was determined and assessed. The determinations were carried out using atomic absorption spectroscopy (AAS) in a DMA-1 mercury analyzer. Based on the estimated daily intake (EDI), target hazard quotient values (THQ), and tolerable weekly intake (TWI), the toxicological risk associated with the intake of total mercury and methylmercury (MeHg) from the products tested was also estimated. The analysis indicated that the highest Hg content was in rice cakes and the lowest in white rice and rice noodles. Total mercury content was found to be below the maximum permitted level. The estimated daily intake (EDI) and target hazard quotient (THQ) values for THg and MeHg in rice and rice products were lower than 1. These findings suggest that the food items examined pose no health risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study aimed to evaluate the environmental impact of dental materials: commercial composite Tetric EvoCeram®, glass ionomer Equia Forte® HT Fil, laboratory-prepared composite, alkasite Cention® Forte, amalgam Amalcap® Plus, and samples from dental chair drainage systems (DCDS). Methacrylate monomers were detected in the eluates of experimental and commercials composites, and alkasite. In DCDS samples solely mercury was found at concentrations of 0.08-1.86 μg/L. The experimental composite (48 h incubation) exhibited the highest toxicity on zebrafish Danio rerio (LC 50 =0.70 g/L), followed by amalgam (LC 50 =8.27 g/L) < Tetric EvoCeram® (LC 50 =10.94 g/L) < Equia Forte® HT Fil (LC 50 =24.84 g/L) < Cention® Forte (LC 50 =32.22 g/L). Exposure of zebrafish to DCDS samples resulted in decreased larval body length and increased occurrences of edema and blood accumulation. The results obtained highlight the need for additional monitoring and further research on the release of unreacted monomers and mercury from dental materials and their environmental impact., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The primary route of mercury exposure for the general population is through consumption of contaminated seafood. There is a biological basis for an adverse effect of mercury exposure on human fertility. The goal of this review was to evaluate the existing literature on the association between mercury and pregnancy, among men and women attempting to conceive with and without assisted reproductive technology (ART). Systematic searches were performed in PubMed, EMBASE, Scopus and Web of Science for papers published up to March 2023 with no early date restriction, only including studies with a biomarker measurement of mercury exposure. We identified 11 studies examining mercury and natural fertility and 12 studies examining mercury and outcomes of assisted reproduction (implantation or clinical pregnancy). The accumulated evidence provides some support for a null association between bodily mercury concentrations and natural fertility among women, however, a large proportion of studies did not report adjusted estimates or were extremely imprecise. The majority of studies of natural fertility were also cross-sectional in nature. There was no evidence for an inverse or null association between mercury and natural fertility among men, or mercury and ART outcomes among men or women. In spite of biological plausibility, the existing evidence includes studies that are imprecise and often conflicting and does not allow us to make definitive conclusions on the associations of mercury exposure with successful pregnancy. Additional, larger studies are warranted, especially among individuals with high concentrations of mercury exposure as these individuals may be underrepresented in the current literature., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Mercury (Hg) toxicity is an increasing problem worldwide, with a negative impact on the environment and living organisms including both animals and plants. In this study, we analyzed molecular and biochemical changes related to Hg toxicity in wheat (Triticum aestivum L.) seedlings. Seven-day-old seedlings were exposed to various concentrations (5, 10, and 20 µM) of HgCl2 for 24 and 48 h. Our results showed that HgCl2 treatments led to an increase in the Hg content of wheat leaves in a time- and concentration-dependent manner. Furthermore, significant increases were observed in hydrogen peroxide, malondialdehyde, and proline contents in response to Hg toxicity. While all HgCl2 treatments decreased the level of superoxide dismutase (SOD), the level of catalase (CAT) was reduced only in seedlings exposed to 5 µM of HgCl2. Mercury stress caused a decline in the expression of Cu/Zn-SOD, Fe-SOD, TaWRKY19, and TaDREB1 genes at both exposure times. On the other hand, 10 and 20 µM HgCl2 treatments caused significant induction (1.9 to 6.1-fold) in the expression of the CAT gene in wheat leaves. The mRNA level of the Mn-SOD and TaWRKY2 genes showed different patterns depending on the concentration and exposure period of HgCl2. In conclusion, the findings of this work demonstrate that Hg toxicity causes oxidative damage in wheat seedlings and changes the expression of some genes encoding WRKY and DREB transcription factor families, which have important functions in abiotic stress response. [ABSTRACT FROM AUTHOR]

The toxic effects of mercury in earthworms and the potential alleviation effect of hydrogen-rich water (HRW) using ATR-FTIR and LC–MS analysis methods were investigated. Different concentrations of mercury chloride (H1: 5 µg/mL, H2: 10 µg/mL, H3: 20 µg/mL, H4: 40 µg/mL, and C1: control) and mercury chloride prepared in hydrogen-rich water (H5: 5 µg/mL, H6: 10 µg/mL, H7: 20 µg/mL, H8: 40 µg/mL, and C2: control) were injected into earthworms. The changes and reductions in some bands representing proteins, lipids, and polysaccharides (3280 cm−1, 2922 cm−1, 2855 cm−1, 1170 cm−1, and 1047 cm−1) showed that protective effects could occur in groups prepared with hydrogen-rich water. In the FTIR results, it was found that these bands in the H3 group were more affected and decreased by the influence of mercury on earthworms than the H7 group prepared with hydrogen. LC–MS analysis showed that the changes in some ions of the highest dose groups (H4 and H8) were different, and mercury caused oxidative DNA damage in earthworms. When the high-level application groups of mercury, i.e., H4 and H8 were compared with the controls, the ion exchange ([M + H] + ; m/z 283.1) representing the 8-Oxo-dG level in earthworms was higher in the H4 group than the H8 group. This reveals that HRW exhibited the potential ability to alleviate the toxic effects of mercury; however, a longer period of HRW treatment may be necessary to distinguish an obvious effect. The ATR-FTIR spectroscopy provided a rapid and precise method for monitoring the changes in biological tissues caused by a toxic compound at the molecular level. [ABSTRACT FROM AUTHOR]

Background: The extent to which prenatal low-level mercury (Hg) exposure through maternal fish intake and heavy metals exposure affect children’s neurodevelopment is controversial and may appear in the long term. In 2007, a prospective cohort, the Northern Adriatic Cohort II (NAC-II), was established to investigate the association between prenatal Hg exposure from maternal fish consumption and child neurodevelopment. The study enrolled 900 pregnant women, and 632 and 470 children underwent neurodevelopmental evaluation at 18 and 40 months of age, respectively. The NAC-II cohort is a part of the Mediterranean cohort in the “Public health impact of long-term, low-level, mixed element exposure in susceptible population strata” project. Methods: This protocol describes the follow-up assessment of the effects of prenatal low level Hg and other heavy metals exposure on the developing nervous system of the children born within the NAC-II who reached the age of 7 years. Child diet components are estimated through a Diet Diary. Child hair and urine are collected for determination of Hg level. In addition, levels of other potentially neurotoxic metals, namely Manganese, Cadmium, Lead, Arsenic, and Selenium, are also measured in the same matrices. Discussion: This protocol extends to the first years of schooling age the evaluation of the neurotoxicant effect of Mercury and of the other heavy metals on children’s neurodevelopment, adjusting for the potential confounders, such as the lifestyles and social economic status of children’s families. Longitudinal analysis of neurodevelopment, assessed in different ages (18 months, 40 months, and 7 years), are performed.

Rapid development has been associated with mercury pollution in the aquatic environment, leading to mercury toxicity in fish and other aquatic organisms. Histopathological abnormalities such as hyperplasia, inflammation, and necrosis have been observed in various fish tissues as a result of mercury contamination based on organic mercury (methylmercury) and inorganic mercury (mercuric chloride) exposure via dietary or water exposure, respectively, with different duration doses of mercury. Knowing that tissue changes occurred at an important part of each organ that played various critical roles in the normal physiological actions of fish, it is critical to understand how fish respond to mercury contamination and how this heavy metal element affects their general well-being. This review paper focuses on major tissue histopathology changes in response to mercury toxicity and their potential use as a mercury contamination indicator in fish.

Mercury (Hg) toxicity impairs plant growth and yield. Thus, a better understanding of Hg-induced impairment is needed. In alfalfa, Hg toxicity caused a significant decrease in morphological parameters, as well as increased electrolyte leakage and cell death. The Hg toxicity also adversely affected chlorophyll score and Fv/Fm (maximal quantum yield of PSII) in leaves. This was linked to lower MsIRT1 (Fe-regulated transporter) expression in roots, implying that Hg hinders Fe acquisition in alfalfa. Further, MsSULTR1;2 (sulfate transporter 1.2) and MsSULTR1;3 (sulfate transporter 1.3) were downregulated accompanied by the lower S status in root and shoot, indicating disturbance in S uptake in Hg-treated alfalfa. In silico analysis demonstrated that MsIRT1, MsSULTR1;2 and MsSULTR1;3 proteins are localized in the plasma membrane and showed close partnerships with several Arabidopsis genes, such as FRO2 (ferric reduction oxidase 2), FRU (FER-like regulator of Fe), bHLH39 (stress-responsive bHLH transcription factor) and protein domains (sulfate anion transporter, SLC26A/SuIP transporter) mainly linked to Fe and S uptake, respectively. Finally, photosynthetic disturbance induced by low Fe and S levels along with oxidative stress in cells is related to growth retardation in Hg-exposed alfalfa. These results could be used to develop Hg-tolerant alfalfa plants through breeding or transgenic programs. Supplemental data for this article is available online at https://doi.org/10.1080/11263504.2021.1985005. [ABSTRACT FROM AUTHOR]

Rapid development has been associated with mercury pollution in the aquatic environment, leading to mercury toxicity in fish and other aquatic organisms. Histopathological abnormalities such as hyperplasia, inflammation, and necrosis have been observed in various fish tissues as a result of mercury contamination based on organic mercury (methylmercury) and inorganic mercury (mercuric chloride) exposure via dietary or water exposure, respectively, with different duration doses of mercury. Knowing that tissue changes occurred at an important part of each organ that played various critical roles in the normal physiological actions of fish, it is critical to understand how fish respond to mercury contamination and how this heavy metal element affects their general well-being. This review paper focuses on major tissue histopathology changes in response to mercury toxicity and their potential use as a mercury contamination indicator in fish. [ABSTRACT FROM AUTHOR]

Coix lacryma-jobi L. is a traditional medicinal plant in east Asia and is an important crop in Guizhou province, southwest China, where there are elevated levels of soil mercury and arsenic (As). Exposure to multiple potentially toxic elements (PTEs) may affect plant accumulation of metal(loid)s and food safety in regions with high geological metal concentrations. Field experiments were conducted to study the effects of PTEs on metal(loid) accumulation and physiological response of C. lacryma in different plant parts at three pollution levels. Total root length, number of root tips, number of branches, and number of root crosses increased with increasing pollution level, with increases in highly polluted areas of 44.2, 57.0, 79.6, and 97.2%, respectively, compared to lightly polluted areas. Under multi-element stress the activity of C. lacryma antioxidant oxidase showed an increase at low and medium PTE concentrations and inhibition at high concentrations. The As contents were all below the maximum limit of cereal food contaminants in China (GB 2762-2022, As < 0.5 mg kg -1 ). The stems had high Tl bioconcentration factors but the translocation factors from stem to grain were very low, indicating that the stems may be a key plant part restricting Tl transport to the grains. C. lacryma increased root retention and reduced the transport effect, thus reducing metal accumulation in the grains. C. lacryma adapted to PTE stress through root remodeling and enhanced antioxidant enzyme activities., (© 2024. The Author(s).)