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Arsenic pollution in paddy fields has become a public concern by seriously threatening rice growth, food security and human health. In this review, we delve into the biogeochemical behaviors of arsenic in paddy soil-rice system, systemically revealing the complexity of its migration and transformation processes, including the release of arsenic from soil to porewater, uptake and translocation of arsenic by rice plants, as well as transformation of arsenic species mediated by microorganism. Especially, microbial processes like reduction, oxidation and methylation of arsenic, as well as the coupling of arsenic with carbon, iron, sulfur and nitrogen cycling through microbes and related mechanisms were highlighted. Environmental factors like pH, redox potential, organic matter, minerals, nutrient elements, microorganisms and periphyton significantly influence these processes through different pathways, which are discussed in this review. Furthermore, the current progress in remediation strategies, including agricultural interventions, passivation, phytoremediation and microbial remediation is explored, and their potential and limitations are analyzed to address the gaps. This review offers comprehensive perspectives on the complicated behaviors of arsenic and influence factors in paddy soil-rice system and provides a scientific basis for developing effective arsenic pollution control strategies.
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Metalloproteins binding with trace elements play a crucial role in biological processes and on the contrary, those binding with exogenous heavy metals have adverse effects. However, the methods for rapid, high sensitivity and simultaneous analysis of these metalloproteins are still lacking. In this study, a fast method for simultaneously determination of both essential and toxic metal-containing proteins was developed by coupling size exclusion chromatography (SEC) with inductively coupled plasma tandem mass spectrometry (ICP-MS/MS). After optimization of the separation and detection conditions, seven metalloproteins with different molecular weight (from 16.0 to 443.0 kDa) were successfully separated within 10 min and the proteins containing iron (Fe), copper (Cu), zinc (Zn), iodine (I) and lead (Pb) elements could be simultaneously detected with the use of oxygen as the collision gas in ICP-MS/MS. Accordingly, the linear relationship between log molecular weight and retention time was established to estimate the molecular weight of unknown proteins. Thus, the trace metal and toxic metal containing proteins could be detected in a single run with high sensitivity (detection limits in the range of 0.0020-2.5 µg/mL) and good repeatability (relative standard deviations lower than 4.5 %). This method was then successfully used to analyze metal (e.g., Pb, Zn, Cu and Fe) binding proteins in the blood of Pb-intoxicated patients, and the results showed a negative correlation between the contents of zinc and lead binding proteins, which was identified to contain hemoglobin subunit. In summary, this work provided a rapid and sensitive tool for screening metal containing proteins in large number of biological samples.
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Cromatografia em Gel , Limite de Detecção , Metaloproteínas , Espectrometria de Massas em Tandem , Cromatografia em Gel/métodos , Espectrometria de Massas em Tandem/métodos , Humanos , Reprodutibilidade dos Testes , Metaloproteínas/sangue , Metaloproteínas/química , Metaloproteínas/análise , Modelos Lineares , Metais Pesados/sangue , Metais Pesados/análise , Metais Pesados/química , AnimaisRESUMO
Complexes with low-molecular-weight thiols are crucial species of methylmercury (MeHg) excreted by anaerobic Hg-methylating microbes, notably, MeHg-cysteine (MeHg-Cys). As MeHg-Cys diffuses into surface water, it would undergo a ligand exchange process with dissolved organic matter (DOM) under nonsulfidic conditions, inevitably altering MeHg speciation and bioavailability to phytoplankton. In this study, we investigated the competitive binding kinetics between MeHg-Cys and Suwannee River natural organic matter, and their influence on the adsorption and uptake of MeHg by the cyanobacterium, Synechocystis sp. PCC6803. Liquid chromatography-inductively coupled plasma mass spectrometry was employed to monitor the kinetics processes involving competition of DOM with Cys for MeHg binding, which revealed that competitive binding kinetics were dictated by the abundance of thiol moieties in DOM. Thiol concentrations of 0.97 and 49.34 µmol of thiol (g C)-1 resulted in competitive binding rate constant (k values) of 0.30 and 3.47 h-1, respectively. Furthermore, the time-dependent competitive binding of DOM toward MeHg-Cys significantly inhibited MeHg adsorption and uptake by cyanobacteria, an effect that was amplified by an increased thiol abundance in DOM. These findings offer valuable insights into the kinetic characteristics of MeHg's fate and transport, as well as their impact on bioconcentration in aquatic organisms within natural aquatic ecosystems.
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Compostos de Metilmercúrio , Compostos de Sulfidrila , Compostos de Metilmercúrio/metabolismo , Compostos de Metilmercúrio/química , Adsorção , Cinética , Compostos de Sulfidrila/metabolismo , Compostos de Sulfidrila/química , Cisteína/metabolismo , Cisteína/química , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/químicaRESUMO
Dominant microorganisms and functional genes, including hgcA, hgcB, merA, and merB, have been identified to be responsible for mercury (Hg) methylation or methylmercury (MeHg) demethylation. However, their in situ correlation with MeHg levels and the processes of Hg methylation and MeHg demethylation in coastal areas remains poorly understood. In this study, four functional genes related to Hg methylation and MeHg demethylation (hgcA, hgcB, merA, and merB) were all detected in the sediments of the Eastern China Coastal Seas (ECCSs) (representative coastal seas highly affected by human activities) using metagenomic approaches. HgcA was identified to be the key gene controlling the in situ net production of MeHg in the ECCSs. Based on metagenomic analysis and incubation experiments, sulfate-reducing bacteria were identified as the dominant microorganisms controlling Hg methylation in the ECCSs. In addition, hgcA gene was positively correlated with the MeHg content and Hg methylation rates, highlighting the potential roles of Hg methylation genes and microorganisms influenced by sediment physicochemical properties in MeHg cycling in the ECCSs. These findings highlighted the necessity of conducting similar studies in other natural systems for elucidating the molecular mechanisms underlying MeHg production in aquatic environments.
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Sedimentos Geológicos , Compostos de Metilmercúrio , Oceanos e Mares , Poluentes Químicos da Água , Sedimentos Geológicos/microbiologia , Compostos de Metilmercúrio/metabolismo , China , Poluentes Químicos da Água/metabolismo , Bactérias/metabolismo , Bactérias/genética , Biodegradação Ambiental , Metilação , Mercúrio/metabolismo , Genes BacterianosRESUMO
Zinc (Zn) is an essential trace element that is required for various biological functions, but excessive exposure to Zn is associated with many disorders and even diseases. However, the health effects and underlying mechanisms of long-term and high concentration exposure of Zn remain to be unclear. In the present study, we investigated the association between occupational exposure to Zn and liver function indicators (like alanine aminotransferase (ALT)) in workers. We found a positive association between Zn exposure and ALT level in workers. Workers having higher blood Zn (7735.65 (1159.15) µg/L) shows a 30.4 % increase in ALT level compared to those with lower blood Zn (5969.30 (989.26) µg/L). Furthermore, we explored the effects of phospholipids (PLs) and their metabolism on ALT level and discovered that Zn exposure in workers was associated with changes in PL levels and metabolism, which had further effects on increased ALT levels in workers. The study provides insights into the relationship between occupational Zn exposure and liver function, highlights the risk of long-term exposure to high concentrations of Zn, and paves the way for understanding the underlying mechanisms of Zn exposure on human health.
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Alanina Transaminase , Exposição Ocupacional , Fosfolipídeos , Zinco , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alanina Transaminase/sangue , Alanina Transaminase/metabolismoRESUMO
Sulfate-reducing bacteria (SRB) play pivotal roles in the biotransformation of mercury (Hg). However, unrevealed global responses of SRB to Hg have restricted our understanding of details of Hg biotransformation processes. The absence of protein-protein interaction (PPI) network under Hg stimuli has been a bottleneck of proteomic analysis for molecular mechanisms of Hg transformation. This study constructed the first comprehensive PPI network of SRB in response to Hg, encompassing 67 connected nodes, 26 independent nodes, and 121 edges, covering 93% of differentially expressed proteins from both previous studies and this study. The network suggested that proteomic changes of SRB in response to Hg occurred globally, including microbial metabolism in diverse environments, carbon metabolism, nucleic acid metabolism and translation, nucleic acid repair, transport systems, nitrogen metabolism, and methyltransferase activity, partial of which could cover the known knowledge. Antibiotic resistance was the original response revealed by this network, providing insights into of Hg biotransformation mechanisms. This study firstly provided the foundational network for a comprehensive understanding of SRB's responses to Hg, convenient for exploration of potential targets for Hg biotransformation. Furthermore, the network indicated that Hg enhances the metabolic activities and modification pathways of SRB to maintain cellular activities, shedding light on the influences of Hg on the carbon, nitrogen, and sulfur cycles at the cellular level.
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Mercúrio , Mercúrio/metabolismo , Mapas de Interação de Proteínas , Proteínas de Bactérias/metabolismo , Biotransformação , Sulfatos/metabolismo , Bactérias/metabolismo , Proteômica , Bactérias Redutoras de Enxofre/metabolismoRESUMO
Household products, in response to regulations, increasingly incorporate phthalate (PAE) alternatives instead of traditional PAEs. However, limited information exists regarding the fate and exposure risk of these PAE alternatives and their monoesters in indoor environments. The contamination levels of PAE alternatives and their monoesters in indoor dust might vary across regions due to climate, population density, industrial activities, and interior decoration practices. By analyzing indoor dust samples from six geographical regions across China, this study aims to shed light on concentrations, profiles, and human exposure to 12 PAE alternatives and 9 their monoesters. Bis(2-ethylhexyl) benzene-1,4-dicarboxylate (DEHTP), tributyl 2-acetyloxypropane-1,2,3-tricarboxylate (ATBC), and tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate (TOTM) were the main PAE alternatives in dust across all regions. The total concentrations of 12 PAE alternatives ranged from 0.125 to 4160 µg/g in indoor dust. High molecular weight PAE alternatives had significantly correlated concentrations (p < 0.05) based on Spearman analysis, suggesting their co-use in heat-resistant plastic products. A collective of nine monoesters were identified in most samples, with total concentrations ranging from 0.048 to 29.6 µg/g. The median concentrations of PAE alternatives were highest in North China (66.8 µg/g), while those of monoesters were highest in Southwest China (6.93 µg/g). A significant correlation (p < 0.05) between the concentrations of DEHTP and its monoester suggested that degradation could be a potential source of monoesters. Although hazard quotients (HQs) have been calculated to suggest that the current exposure is unlikely to pose a significant health risk, the lack of toxicity threshold data and the existence of additional exposure pathways necessitate a further confirmation.
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Poluição do Ar em Ambientes Fechados , Poeira , Ácidos Ftálicos , Poeira/análise , China , Ácidos Ftálicos/análise , Humanos , Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/análise , Poluentes Atmosféricos/análise , Ésteres/análise , Monitoramento AmbientalRESUMO
BACKGROUND: Trace levels of organic and inorganic lead and mercury species in the environment, including divalent lead (Pb2+), trimethyllead (TML), divalent mercury (Hg2+), monomethylmercury (MeHg), and ethylmercury (EtHg), are highly toxic to humans and ecology. It is of great importance for speciation of lead and mercury to evaluate the toxicity of lead and mercury and their biogeochemistry in the environment. However, simultaneous multi-elemental enrichment and speciation at trace level remains a challenge. There are few reports of simultaneous magnetic solid-phase extraction (MSPE) of organic and inorganic lead and mercury species at trace level in the real water. RESULTS: In this work, a novel core-shell magnetic hydrazine-linked covalent organic frameworks (Fe3O4@COF-TCH) was prepared for the first time by grafting hydrazine-linked COFs on the Fe3O4 nanoparticles. Fe3O4@COF-TCH with abundant thione and imino groups has strong adsorption for lead and mercury species. Based on it, a simple and practical magnetic solid-phase extraction high-performance liquid chromatography-inductively coupled plasma mass spectrometry (MSPE-HPLC-ICP-MS) method was developed for extraction and determination of trace lead and mercury species, including Hg2+, MeHg, EtHg, Pb2+ and TML. The limits of detection (3δ) of the developed method were 0.08, 0.81, 0.90, 0.56 and 0.88 ng L-1 with the enrichment factors (EFs) of 384, 376, 379, 389 and 360-fold for Pb2+, TML, Hg2+, MeHg and EtHg, respectively. The high accuracy and reproducibility have been proved by the spiked recoveries (94.4-103 %) in real samples. SIGNIFICANCE: The proposed method with simple operation and high sensitivity has been successfully applied to simultaneous speciation of lead and mercury at trace levels in the water samples with complicated matrices, including underground water, surface water, sea water. Meanwhile, it has the advantages of cost-saving, labor-saving and time-saving and is suitable for the investigation and risk assessment in water. The development of MSPE-HPLC-ICP-MS method provides ideas and guidance for the simultaneous multi-elemental enrichment and speciation.
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Permeabilities of various trace elements (TEs) through the blood-follicle barrier (BFB) play an important role in oocyte development. However, it has not been comprehensively described as well as its involved biological pathways. Our study aimed to construct a blood-follicle distribution model of the concerned TEs and explore their related biological pathways. We finally included a total of 168 women from a cohort of in vitro fertilization-embryo transfer conducted in two reproductive centers in Beijing City and Shandong Province, China. The concentrations of 35 TEs in both serum and follicular fluid (FF) samples from the 168 women were measured, as well as the multiomics features of the metabolome, lipidome, and proteome in both plasma and FF samples. Multiomics features associated with the transfer efficiencies of TEs through the BFB were selected by using an elastic net model and further utilized for pathway analysis. Various machine learning (ML) models were built to predict the concentrations of TEs in FF. Overall, there are 21 TEs that exhibited three types of consistent BFB distribution characteristics between Beijing and Shandong centers. Among them, the concentrations of arsenic, manganese, nickel, tin, and bismuth in FF were higher than those in the serum with transfer efficiencies of 1.19-4.38, while a reverse trend was observed for the 15 TEs with transfer efficiencies of 0.076-0.905, e.g., mercury, germanium, selenium, antimony, and titanium. Lastly, cadmium was evenly distributed in the two compartments with transfer efficiencies of 0.998-1.056. Multiomics analysis showed that the enrichment of TEs was associated with the synthesis and action of steroid hormones and the glucose metabolism. Random forest model can provide the most accurate predictions of the concentrations of TEs in FF among the concerned ML models. In conclusion, the selective permeability through the BFB for various TEs may be significantly regulated by the steroid hormones and the glucose metabolism. Also, the concentrations of some TEs in FF can be well predicted by their serum levels with a random forest model.
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Aprendizado de Máquina , Oligoelementos , Humanos , Oligoelementos/metabolismo , Feminino , Líquido Folicular/metabolismo , Líquido Folicular/química , China , MultiômicaRESUMO
Background: The fetal stage is pivotal for growth and development, making it susceptible to the adverse effects of prenatal metal(loid)s exposure. This study evaluated the influence of gestational diabetes mellitus (GDM) on the placental transfer efficiency (PTE) of metal(loid)s and thus assessed the associated risks of prenatal metal(loid)s exposure.Materials and method: Designed as a case-control study, it incorporated 114 pregnant participants: 65 without complications and 49 diagnosed with GDM. We utilized inductively coupled plasma mass spectrometry to quantify seven metal(loid)s - manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), arsenic (As), and cadmium (Cd) - in both maternal venous blood and umbilical cord blood.Result: We compared metal(loid)s concentrations and their PTE in the maternal and cord blood between the two groups. Notably, Cu, Ga, As, and Co levels in the umbilical cord blood of the GDM group (657.9 ± 167.2 µg/L, 1.23 ± 0.34 µg/L, 5.19 ± 2.58 µg/L, 1.09 ± 2.03 µg/L) surpassed those of the control group, with PTE of Co showing a marked increase in GDM group (568.8 ± 150.4 µg/L, 1.05 ± 0.31 µg/L, 4.09 ± 2.54 µg/L, 0.47 ± 0.91 µg/L), with PTE of Co showing a marked increase in GDM group (p < 0.05). The PTE of Ni exhibited a reduction in the GDM group relative to the control group, yet this decrease did not reach statistical significance.Conclusion: This study indicates that GDM can influence the placental transfer efficiency of certain metal(loid)s, leading to higher concentrations of Co, Cu, Ga, and As in the umbilical cord blood of the GDM group. The marked increase in the PTE of Co suggests a potential link to placental abnormal angiogenesis due to GDM.
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Arsênio , Diabetes Gestacional , Gravidez , Feminino , Humanos , Cobalto , Mães , Estudos de Casos e Controles , PlacentaRESUMO
The Paris Agreement and the Minamata Convention on Mercury are two of the most important environmental conventions being implemented concurrently, with a focus on reducing carbon and mercury emissions, respectively. The relation between mercury and carbon influences the interactions and outcomes of these two conventions. This perspective investigates the link between mercury and CO2, assessing the consequences and exploring the policy implications of this link. We present scientific evidence showing that mercury and CO2 levels are negatively correlated under natural conditions. As a result of this negative correlation, the CO2 level under the current mercury reduction scenario is predicted to be 2.4-10.1 ppm higher than the no action scenario by 2050, equivalent to 1.0-4.8 years of CO2 increase due to human activity. The underlying causations of this negative correlation are complex and need further research. Economic analysis indicates that there is a trade-off between the benefits and costs of mercury reduction actions. As reducing mercury emission may inadvertently undermine efforts to achieve climate goals, we advocate for devising a coordinated implementation strategy for carbon and mercury conventions to maximize synergies and reduce trade-offs.
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Dióxido de Carbono , Mercúrio , Humanos , Mercúrio/análise , Políticas , ClimaRESUMO
Algae are an entry point for mercury (Hg) into the food web. Bioconcentration of Hg by algae is crucial for its biogeochemical cycling and environmental risk. Herein, considering the cell heterogeneity, we investigated the bioconcentration of coexisting isotope-labeled inorganic (199IHg) and methyl Hg (201MeHg) by six typical freshwater and marine algae using dual-mass single-cell inductively coupled plasma mass spectrometry (scICP-MS). First, a universal pretreatment procedure for the scICP-MS analysis of algae was developed. Using the proposed method, the intra- and interspecies heterogeneities and the kinetics of Hg bioconcentration by algae were revealed at the single-cell level. The heterogeneity in the cellular Hg contents is largely related to cell size. The bioconcentration process reached a dynamic equilibrium involving influx/adsorption and efflux/desorption within hours. Algal density is a key factor affecting the distribution of Hg between algae and ambient water. Cellular Hg contents were negatively correlated with algal density, whereas the volume concentration factors almost remained constant. Accordingly, we developed a model based on single-cell analysis that well describes the density-driven effects of Hg bioconcentration by algae. From a novel single-cell perspective, the findings improve our understanding of algal bioconcentration governed by various biological and environmental factors.
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Mercúrio , Mercúrio/metabolismo , Espectrometria de Massas , Compostos de Metilmercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Cadeia Alimentar , Análise de Célula ÚnicaRESUMO
Mounting evidence suggests that environmental pollutants may affect reproductive health, potentially leading to adverse outcomes like pregnancy loss. However, it remains unclear whether exposure to synthetic phenolic antioxidants (SPAs) correlates with early pregnancy loss (EPL). This study explores SPA exposure's link to EPL and its potential molecular mechanisms. From 2021 to 2022, 265 early pregnant women (136 serum and 129 villus samples) with and without EPL were enrolled. We quantified 17 SPAs in serum and chorionic villus, with AO1010, AO3114, BHT, AO2246, and BHT-Q frequently being detected, suggesting their ability to cross the placental barrier. AO1135 showed a positive relationship with EPL in sera, indicating a significant monotonic dose-response relationship (p-trend <0.001). BHT-Q exhibited a similar relationship with EPL in villi. Inhibitory effects of BHT-Q on estradiol (E2) were observed. Molecular docking revealed SPA-protein interactions involved in E2 synthesis. SPA-induced EPL might occur with specific serum levels of AO1135 and certain villus levels of AO1010, BHT-Q, and AO2246. BHT-Q emerges as a potential biomarker for assessing EPL risk. This study provides insights into understanding of the exposure to SPAs and potential adverse outcomes in pregnant women.
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Aborto Espontâneo , Antioxidantes , Fenóis , Feminino , Humanos , Gravidez , Aborto Espontâneo/induzido quimicamente , Adulto , Simulação de Acoplamento Molecular , Poluentes AmbientaisRESUMO
Biodegradation of soil organic matter (SOM), which involves greenhouse gas (GHG) emissions, plays an essential role in the global carbon cycle. Over the past few decades, this has become an important research focus, particularly in natural ecosystems. SOM biodegradation significantly affects contaminants in the environment, such as mercury (Hg) methylation, producing highly toxic methylmercury (MeHg). However, the potential link between GHG production from SOM turnover in contaminated soils and biogeochemical processes involving contaminants remains unclear. In this study, we investigated the dynamics of GHG, MeHg production, and the relationship between biogeochemical processes in soils from two typical Hg mining sites. The two contaminated soils have different pathways, explaining the significant variations in GHG and MeHg production. The divergence of the microbial communities in these two biogeochemical processes is essential. In addition to the microbial role, abiotic factors such as Hg species can significantly affect MeHg production. On the other hand, we found an inverse relationship between CH4 and MeHg, suggesting that carbon emission reduction policies and management could inadvertently increase the MeHg levels. This highlights the need for an eclectic approach to organic carbon sequestration and contaminant containment. These findings suggest that it is difficult to establish a general pattern to describe and explain the SOM degradation and MeHg production in contaminated soils within the specific scenarios. However, this study provides a case study and helpful insights for further understanding the links between environmental risks and carbon turnover in Hg mining areas.
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Mercúrio , Compostos de Metilmercúrio , Oryza , Poluentes do Solo , Solo , Ecossistema , Poluentes do Solo/análise , Mercúrio/análise , Carbono , Biodegradação Ambiental , Monitoramento AmbientalRESUMO
Pseudomonas aeruginosa (P. aeruginosa), a drug-resistant Gram-negative pathogen, is listed among the "critical" group of pathogens by the World Health Organization urgently needing efficacious antibiotics in the clinics. Nanomaterials especially silver nanoparticles (AgNPs) due to the broad-spectrum antimicrobial activity are tested in antimicrobial therapeutic applications. Pathogens rapidly develop resistance to AgNPs; however, the health threat from antibiotic-resistant pathogens remains challenging. Here we present a strategy to prevent bacterial resistance to silver nanomaterials through imparting chirality to silver nanoclusters (AgNCs). Nonchiral AgNCs with high efficacy against P. aeruginosa causes heritable resistance, as indicated by a 5.4-fold increase in the minimum inhibitory concentration (MIC) after 9 repeated passages. Whole-genome sequencing identifies a Rhs mutation related to the wall of Gram-negative bacteria that possibly causes morphology changes in resistance compared to susceptible P. aeruginosa. Nevertheless, AgNCs with laevorotary chirality (l-AgNCs) induce negligible resistance even after 40 repeated passages and maintain a superior antibacterial efficiency at the MIC. l-AgNCs also show high cytocompatibility; negligible cytotoxicity to mammalian cells including JB6, H460, HEK293, and RAW264.7 is observed even at 30-fold MIC. l-AgNCs thus are examined as an alternative to levofloxacin in vivo, healing wound infections of P. aeruginosa efficaciously. This work provides a potential opportunity to confront the rising threat of antimicrobial resistance by developing chiral nanoclusters.
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Anti-Infecciosos , Nanopartículas Metálicas , Animais , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Prata/farmacologia , Prata/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Células HEK293 , Pseudomonas aeruginosa , Testes de Sensibilidade Microbiana , MamíferosRESUMO
Mono(2-ethylhexyl) phthalate (MEHP), as a highly toxic and biologically active phthalate metabolite, poses considerable risks to the environment and humans. Despite the existence of in vitro studies, there is a lack of in vivo experiments assessing its toxicity, particularly thyroid toxicity. Herein, we investigated the thyroid-disrupting effects of MEHP and the effects on growth and development of maternal exposure to MEHP during pregnancy and lactation on the offspring modeled by SD rats. We found that thyroid hormone (TH) homeostasis was disrupted in the offspring, showing a decrease in total TH levels, combined with an increase in free TH levels. Nonhomeostasis ultimately leads to weight loss in female offspring, longer anogenital distance in male offspring, prolonged eye-opening times, and fewer offspring. Our findings indicate that maternal exposure to MEHP during pregnancy and lactation indirectly influences the synthesis, transport, transformation, and metabolism of THs in the offspring. Meanwhile, MEHP disrupted the morphology and ultrastructure of the thyroid gland, leading to TH disruption. This hormonal disruption might ultimately affect the growth and development of the offspring. This study provides a novel perspective on the thyroid toxicity mechanisms of phthalate metabolites, emphasizing the health risks to newborns indirectly exposed to phthalates and their metabolites.
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Dietilexilftalato , Dietilexilftalato/análogos & derivados , Ácidos Ftálicos , Humanos , Gravidez , Masculino , Feminino , Animais , Ratos , Ratos Sprague-Dawley , Hormônios Tireóideos , Ácidos Ftálicos/metabolismo , Dietilexilftalato/toxicidade , Dietilexilftalato/metabolismo , Lactação , Homeostase , Crescimento e DesenvolvimentoRESUMO
The complex and cumbersome preparation of magnetic covalent organic frameworks (COFs) nanocomposites on a small scale limits their application. Herein, a rapid and easy route was employed for the preparation of magnetic thiourea-based COFs nanocomposites. COFs were coated on Fe3O4 nanoparticles at room temperature without a catalyst within approximately 30 min. This method is suitable for the large-scale preparation of magnetic adsorbent. Using the as-prepared magnetic adsorbent (Fe3O4@COF-TpTU), we developed a simple, efficient, and sensitive magnetic solid-phase extraction-high performance liquid chromatography-inductively coupled plasma-mass spectrometry (MSPE-HPLC-ICP-MS) for the enrichment and determination of mercury species, including Hg2+, methylmercury (MeHg), and ethylmercury (EtHg). The effects of the experimental parameters on the extraction efficiency, including solution pH, adsorption and desorption time, composition and volume of the elution solvent, salinity, coexisting ions, and dissolved organic matter, were comprehensively investigated. Under optimised conditions, the limits of detection in the developed method were 0.56, 0.34, and 0.47 ng L-1 with enrichment factors of 190, 195, and 180-fold for Hg2+, MeHg, and EtHg, respectively. The satisfactory spiked recoveries (97.0-103%) in real water samples and high consistency between the certified and determined values in a certified reference material demonstrate the high accuracy and reproducibility of the developed method. The as-proposed method with simple operation, high sensitivity, and excellent anti-matrix interference performance was successfully applied to the enrichment and determination of trace levels of mercury species in the natural samples with complicated matrices, such as underground water, surface water, seawater and biological samples.
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Mercúrio , Estruturas Metalorgânicas , Compostos de Metilmercúrio , Mercúrio/análise , Estruturas Metalorgânicas/química , Cromatografia Líquida de Alta Pressão/métodos , Tioureia , Reprodutibilidade dos Testes , Temperatura , Compostos de Metilmercúrio/análise , Água/química , Fenômenos Magnéticos , Extração em Fase Sólida/métodosRESUMO
To elucidate the potential risks of the toxic pollutant mercury (Hg) in polar waters, the study of accumulated Hg in fish is compelling for understanding the cycling and fate of Hg on a regional scale in Antarctica. Herein, the Hg isotopic compositions of Antarctic cod Notothenia coriiceps were assessed in skeletal muscle, liver, and heart tissues to distinguish the differences in Hg accumulation in isolated coastal environments of the eastern (Chinese Zhongshan Station, ZSS) and the antipode western Antarctica (Chinese Great Wall Station, GWS), which are separated by over 4000 km. Differences in odd mass-independent isotope fractionation (odd-MIF) and mass-dependent fractionation (MDF) across fish tissues were reflection of the specific accumulation of methylmercury (MeHg) and inorganic Hg (iHg) with different isotopic fingerprints. Internal metabolism including hepatic detoxification and processes related to heart may also contribute to MDF. Regional heterogeneity in iHg end-members further provided evidence that bioaccumulated Hg origins can be largely influenced by polar water circumstances and foraging behavior. Sea ice was hypothesized to play critical roles in both the release of Hg with negative odd-MIF derived from photoreduction of Hg2+ on its surface and the impediment of photochemical transformation of Hg in water layers. Overall, the multitissue isotopic compositions in local fish species and prime drivers of the heterogeneous Hg cycling and bioaccumulation patterns presented here enable a comprehensive understanding of Hg biogeochemical cycling in polar coastal waters.
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Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Mercúrio/análise , Regiões Antárticas , Isótopos de Mercúrio/análise , Bioacumulação , Camada de Gelo , Monitoramento Ambiental , Compostos de Metilmercúrio/metabolismo , Peixes/metabolismo , Isótopos , Água/metabolismo , Poluentes Químicos da Água/análiseRESUMO
Particulate HgS play crucial roles in the mercury (Hg) cycle. Approximately 20-90% of dissolved Hg can be transformed into particulate HgS by algae. However, detailed knowledge regarding these particles, including sizes and distribution, remains unknown. The present study explored the formation, distribution, and excretion of mercury nanoparticles (HgNPs) in diatom Chaetoceros curvisetus. The results demonstrated that HgNPs (HgS nanoparticles, 29.6-66.2 nm) formed intracellularly upon exposure to 5.0-100.0 µg L-1 Hg(II), accounting for 12-27% of the total Hg. HgNP concentrations significantly increased with increasing intracellular Hg(II) concentrations, while their sizes remained unaffected. HgNPs formed intracellularly and partly accumulated inside the cells (7-11%). Subsequently, the sizes of intracellular HgNPs gradually decreased to facilitate expulsion, 21-50% of which were excreted. These suggested the vital roles of HgNPs in comprehending marine Hg fate. Their unique physicochemical properties and bioavailability would influence Hg biotransformation in the ocean. Additionally, both intracellular and extracellular HgNPs contributed to Hg settling with cells, ultimately leading to Hg burial in sediments. Overall, these findings further deepened our understanding of Hg biotransformation and posed challenges in accurately estimating marine Hg flux and Hg burial.