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1.
J Vis Exp ; (207)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829117

RESUMO

Through various studies on thermoelectric (TE) materials, thin film configuration gives superior advantages over conventional bulk TEs, including adaptability to curved and flexible substrates. Several different thin film deposition methods have been explored, yet magnetron sputtering is still favorable due to its high deposition efficiency and scalability. Therefore, this study aims to fabricate a bismuth telluride (Bi2Te3) and antimony telluride (Sb2Te3) thin film via the radio frequency (RF) magnetron sputtering method. The thin films were deposited on soda lime glass substrates at ambient temperature. The substrates were first washed using water and soap, ultrasonically cleaned with methanol, acetone, ethanol, and deionized water for 10 min, dried with nitrogen gas and hot plate, and finally treated under UV ozone for 10 min to remove residues before the coating process. A sputter target of Bi2Te3 and Sb2Te3 with Argon gas was used, and pre-sputtering was done to clean the target's surface. Then, a few clean substrates were loaded into the sputtering chamber, and the chamber was vacuumed until the pressure reached 2 x 10-5 Torr. The thin films were deposited for 60 min with Argon flow of 4 sccm and RF power at 75 W and 30 W for Bi2Te3 and Sb2Te3, respectively. This method resulted in highly uniform n-type Bi2Te3 and p-type Sb2Te3 thin films.


Assuntos
Antimônio , Bismuto , Telúrio , Bismuto/química , Antimônio/química , Telúrio/química , Ondas de Rádio
2.
BMC Plant Biol ; 24(1): 364, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38702592

RESUMO

BACKGROUND: This study aimed to investigate the alterations in biochemical and physiological responses of oat plants exposed to antimony (Sb) contamination in soil. Specifically, we evaluated the effectiveness of an arbuscular mycorrhizal fungus (AMF) and olive mill waste (OMW) in mitigating the effects of Sb contamination. The soil was treated with a commercial strain of AMF (Rhizophagus irregularis) and OMW (4% w/w) under two different levels of Sb (0 and 1500 mg kg-1 soil). RESULTS: The combined treatment (OMW + AMF) enhanced the photosynthetic rate (+ 40%) and chlorophyll a (+ 91%) and chlorophyll b (+ 50%) content under Sb condition, which in turn induced more biomass production (+ 67-78%) compared to the contaminated control plants. More photosynthesis in OMW + AMF-treated plants gives a route for phenylalanine amino acid synthesis (+ 69%), which is used as a precursor for the biosynthesis of secondary metabolites, including flavonoids (+ 110%), polyphenols (+ 26%), and anthocyanins (+ 63%) compared to control plants. More activation of phenylalanine ammonia-lyase (+ 38%) and chalcone synthase (+ 26%) enzymes in OMW + AMF-treated plants under Sb stress indicated the activation of phenylpropanoid pathways in antioxidant metabolites biosynthesis. There was also improved shifting of antioxidant enzyme activities in the ASC/GSH and catalytic pathways in plants in response to OMW + AMF and Sb contamination, remarkably reducing oxidative damage markers. CONCLUSIONS: While individual applications of OMW and AMF also demonstrated some degree of plant tolerance induction, the combined presence of AMF with OMW supplementation significantly enhanced plant biomass production and adaptability to oxidative stress induced by soil Sb contamination.


Assuntos
Antimônio , Micorrizas , Olea , Poluentes do Solo , Micorrizas/fisiologia , Olea/microbiologia , Poluentes do Solo/metabolismo , Antimônio/metabolismo , Adaptação Fisiológica , Resíduos Industriais , Fotossíntese/efeitos dos fármacos , Biodegradação Ambiental , Biomassa
3.
Environ Pollut ; 352: 124082, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38697246

RESUMO

Antimony (Sb) contamination in certain areas caused by activities such as antimony mining and smelting poses significant risks to human health and ecosystems. In this study, a stable composite material consisting of natural zeolite-supported nanoscale zero-valent iron (Z-ZVI) was successfully prepared. The immobilization effect of Z-ZVI on Sb in contaminated soil was investigated. Experimental results showed that Z-ZVI exhibited superior performance compared to pure nano zero-valent iron (nZVI) in terms of stability, with a lower zeta potential (-25.16 mV) at a pH of 7 and a higher specific surface area (54.54 m2/g). It can be easily applied and dispersed in contaminated soils. Additionally, Z-ZVI demonstrated a more abundant porous structure. After 60 days of treatment with 3% Z-ZVI, the leaching concentration of Sb in the contaminated soil decreased from 1.32 mg/L to 0.31 mg/L (a reduction of 76%), and the concentration of available Sb species decreased from 19.84 mg/kg to 0.71 mg/kg, achieving a fixation efficiency of up to 90%. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis confirmed the effective immobilization of Sb in the soil through reduction of antimonate to antimonite, precipitation, and adsorption processes facilitated by Z-ZVI. Moreover, the addition of Z-ZVI effectively reduced the bioavailability of Sb in the contaminated soil, thereby mitigating its toxicity to earthworms. In conclusion, Z-ZVI can be utilized as a promising material for the safe remediation and antimony and other heavy metal-contaminated soils.


Assuntos
Antimônio , Ferro , Poluentes do Solo , Solo , Zeolitas , Antimônio/química , Poluentes do Solo/química , Zeolitas/química , Ferro/química , Solo/química , Recuperação e Remediação Ambiental/métodos , Adsorção , Animais
4.
Environ Monit Assess ; 196(5): 448, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607467

RESUMO

Soil in mining wastelands is seriously polluted with heavy metals. Zero-valent iron (ZVI) is widely used for remediation of heavy metal-polluted soil because of its excellent adsorption properties; however, the remediation process is affected by complex environmental conditions, such as acid rain and freeze-thaw cycles. In this study, the effects of different pH values and freeze-thaw cycles on remediation of antimony (Sb)- and arsenic (As)-contaminated soil by ZVI were investigated in laboratory simulation experiments. The stability and potential human health risks associated with the remediated soil were evaluated. The results showed that ZVI has a significant stabilizing effect on Sb and As in both acidic and alkaline soils contaminated with dual levels of Sb and As, and the freeze-thaw process in different pH value solution systems further enhances the ability of ZVI to stabilize Sb and As, especially in acidic soils. However, it should be noted that apart from the pH=1.0 solution environment, ZVI's ability to stabilize As is attenuated under other circumstances, potentially leading to leaching of its unstable form and thereby increasing contamination risks. This indicates that the F1 (2% ZVI+pH=1 solution+freeze-thaw cycle) processing exhibits superior effectiveness. After F1 treatment, the bioavailability of Sb and As in both soils also significantly decreased during the gastric and intestinal stages (about 60.00%), the non-carcinogenic and carcinogenic risks of Sb and As in alkaline soils are eliminated for children and adults, with a decrease ranging from 60.00% to 70.00%, while in acidic soil, the non-carcinogenic and carcinogenic risks of As to adults and children is acceptable, but Sb still poses non-carcinogenic risks to children, despite reductions of about 65.00%. These findings demonstrate that soil pH is a crucial factor influencing the efficacy of ZVI in stabilizing Sb and As contaminants during freeze-thaw cycles. This provides a solid theoretical foundation for utilizing ZVI in the remediation of Sb- and As-contaminated soils, emphasizing the significance of considering both pH levels and freeze-thaw conditions to ensure effective and safe treatment.


Assuntos
Antimônio , Arsênio , Humanos , Adulto , Criança , Ferro , Monitoramento Ambiental , Medição de Risco , Solo , Concentração de Íons de Hidrogênio
5.
Nanoscale ; 16(20): 9754-9769, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38625086

RESUMO

Pnictogen nanomaterials have recently attracted researchers' attention owing to their promising properties in the field of electronic, energy storage, and nanomedicine applications. Moreover, especially in the case of heavy pnictogens, their chemistry allows for nanomaterial synthesis using both top-down and bottom-up approaches, yielding materials with remarkable differences in terms of morphology, size, yield, and properties. In this study, we carried out a comprehensive structural and spectroscopic characterization of antimony-based nanomaterials (Sb-nanomaterials) obtained by applying different production methodologies (bottom-up and top-down routes) and investigating the influence of the synthesis on their oxidation state and stability in a biological environment. Indeed, in situ XANES/EXAFS studies of Sb-nanomaterials incubated in cell culture media were carried out, unveiling a different oxidation behavior. Furthermore, we investigated the cytotoxic effects of Sb-nanomaterials on six different cell lines: two non-cancerous (FSK and HEK293) and four cancerous (HeLa, SKBR3, THP-1, and A549). The results reveal that hexagonal antimonene (Sb-H) synthesized using a colloidal approach oxidizes the most and faster in cell culture media compared to liquid phase exfoliated (LPE) antimonene, suffering acute degradation and anticipating well-differentiated toxicity from its peers. In addition, the study highlights the importance of the synthetic route for the Sb-nanomaterials as it was observed to influence the chemical evolution of Sb-H into toxic Sb oxide species, playing a critical role in its ability to rapidly eliminate tumor cells. These findings provide insights into the mechanisms underlying the dark cytotoxicity of Sb-H and other related Sb-nanomaterials, underlining the importance of developing therapies based on controlled and on-demand nanomaterial oxidation.


Assuntos
Antimônio , Nanoestruturas , Oxirredução , Humanos , Antimônio/química , Nanoestruturas/química , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Células HEK293 , Células HeLa , Células A549
6.
Sci Total Environ ; 926: 171937, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38527534

RESUMO

The tremendous application potentiality of transitional metal dichalcogenides (TMDs), such as molybdenum disulfide (MoS2) nanosheets, will unavoidably lead to increasing release into the environment, which could influence the fate and toxicity of co-existed contaminants. The present study discovered that 59.8 % of trivalent antimony [Sb(III)] was transformed by MoS2 to pentavalent Sb [Sb(V)] in aqueous solutions under light illumination, which was due to hole oxidation on the nanosheet surfaces. A synergistic toxicity between MoS2 and Sb(III, V) to algae (Chlorella vulgaris) was observed, as demonstrated by the lower median-effect concentrations of MoS2 + Sb(III)/Sb(V) (13.1 and 20.9 mg/L, respectively) than Sb(III)/Sb(V) (38.8 and 92.5 mg/L, respectively) alone. Particularly, MoS2 at noncytotoxic doses notably increased the bioaccumulation of Sb(III, V) in algae, causing aggravated oxidative damage, photosynthetic inhibition, and structural alterations. Metabolomics indicated that oxidative stress and membrane permeabilization were primarily associated with down-regulated amino acids involved in glutathione biosynthesis and unsaturated fatty acids. MoS2 co-exposure remarkably decreased the levels of thiol antidotes (glutathione and phytochelatins) and aggravated the inhibition on energy metabolism and ATP synthesis, compromising the Sb(III, V) detoxification and efflux. Additionally, extracellular P was captured by the nanosheets, also contributing to the uptake of Sb(V). Our findings emphasized the nonignorability of TMDs even at environmental levels in affecting the ecological hazard of metalloids, providing insight into comprehensive safety assessment of TMDs.


Assuntos
Chlorella vulgaris , Dissulfetos , Metaloides , Antimônio/metabolismo , Molibdênio/toxicidade , Adsorção , Chlorella vulgaris/metabolismo , Glutationa
7.
J Hazard Mater ; 469: 133897, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38442599

RESUMO

Microbial antimony (Sb) oxidation in the root rhizosphere and the formation of iron plaque (IP) on the root surface are considered as two separate strategies to mitigate Sb(III) phytotoxicity. Here, the effect of an Sb-oxidizing bacterium Bacillus sp. S3 on IP characteristics of rice exposed to Sb(III) and its alleviating effects on plant growth were investigated. The results revealed that Fe(II) supply promoted IP formation under Sb(III) stress. However, the formed IP facilitated rather than hindered the uptake of Sb by rice roots. In contrast, the combined application of Fe(II) and Bacillus sp. S3 effectively alleviated Sb(III) toxicity in rice, resulting in improved rice growth and photosynthesis, reduced oxidative stress levels, enhanced antioxidant systems, and restricted Sb uptake and translocation. Despite the ability of Bacillus sp. S3 to oxidize Fe(II), bacterial inoculation inhibited the formation of IP, resulting in a reduction in Sb absorption on IP and uptake into the roots. Additionally, the bacterial inoculum enhanced the transformation of Sb(III) to less toxic Sb(V) in the culture solution, further influencing the adsorption of Sb onto IP. These findings highlight the potential of combining microbial Sb oxidation and IP as an effective strategy for minimizing Sb toxicity in sustainable rice production systems.


Assuntos
Bacillus , Oryza , Poluentes do Solo , Ferro , Antimônio/toxicidade , Raízes de Plantas , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Bactérias , Oxirredução , Compostos Ferrosos
8.
Acta Trop ; 254: 107190, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508372

RESUMO

Pentavalent antimonials are the mainstay treatment against different clinical forms of leishmaniasis. The emergence of resistant isolates in endemic areas has led to treatment failure. Unraveling the underlying resistance mechanism would assist in improving the treatment strategies against resistant isolates. This study aimed to investigate the RNA expression level of glutathione synthetase (GS), Spermidine synthetase (SpS), trypanothione synthetase (TryS) genes involved in trypanothione synthesis, and thiol-dependent reductase (TDR) implicated in drug reduction, in antimony-sensitive and -resistant Leishmania tropica isolates. We investigated 11 antimony-resistant and 11 antimony-sensitive L. tropica clinical isolates from ACL patients. Drug sensitivity of amastigotes was determined in mouse macrophage cell line J774A.1. The RNA expression level in the promastigote forms was analyzed by quantitative real-time PCR. The results revealed a significant increase in the average expression of GS, SpS, and TrpS genes by 2.19, 1.56, and 2.33-fold in resistant isolates compared to sensitive ones. The average expression of TDR was 1.24-fold higher in resistant isolates, which was insignificant. The highest correlation coefficient between inhibitory concentration (IC50) values and gene expression belonged to the TryS, GS, SpS, and TDR genes. Moreover, the intracellular thiol content was increased 2.17-fold in resistant isolates compared to sensitive ones and positively correlated with IC50 values. Our findings suggest that overexpression of trypanothione biosynthesis genes and increased thiol content might play a key role in the antimony resistance of L. tropica clinical isolates. In addition, the diversity of gene expression in the trypanothione system and thiol content among L. tropica clinical isolates highlighted the phenotypic heterogeneity of antimony resistance among the parasite population.


Assuntos
Antimônio , Antiprotozoários , Resistência a Medicamentos , Glutationa , Glutationa/análogos & derivados , Leishmania tropica , Espermidina/análogos & derivados , Leishmania tropica/genética , Leishmania tropica/efeitos dos fármacos , Resistência a Medicamentos/genética , Animais , Antimônio/farmacologia , Humanos , Antiprotozoários/farmacologia , Camundongos , Glutationa/metabolismo , Linhagem Celular , Macrófagos/parasitologia , Concentração Inibidora 50 , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/tratamento farmacológico , Feminino , Adulto , Testes de Sensibilidade Parasitária , Masculino , Reação em Cadeia da Polimerase em Tempo Real
9.
J Hazard Mater ; 469: 133948, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38493633

RESUMO

Bioaccessibility and relative bioavailability of As, Cd, Pb and Sb was investigated in 30 legacy gold mining wastes (calcine sands, grey battery sands, tailings) from Victorian goldfields (Australia). Pseudo-total As concentration in 29 samples was 1.45-148-fold higher than the residential soil guidance value (100 mg/kg) while Cd and Pb concentrations in calcine sands were up to 2.4-fold and 30.1-fold higher than the corresponding guidance value (Cd: 20 mg/kg and Pb: 300 mg/kg). Five calcine sands exhibited elevated Sb (31.9-5983 mg/kg), although an Australian soil guidance value is currently unavailable. Arsenic bioaccessibility (n = 30) and relative bioavailability (RBA; n = 8) ranged from 6.10-77.6% and 10.3-52.9% respectively. Samples containing > 50% arsenopyrite/scorodite showed low As bioaccessibility (<20.0%) and RBA (<15.0%). Co-contaminant RBA was assessed in 4 calcine sands; Pb RBA ranged from 73.7-119% with high Pb RBA associated with organic and mineral sorbed Pb and, lower Pb RBA observed in samples containing plumbojarosite. In contrast, Cd RBA ranged from 55.0-67.0%, while Sb RBA was < 5%. This study highlights the importance of using multiple lines of evidence during exposure assessment and provides valuable baseline data for co-contaminants associated with legacy gold mining activities.


Assuntos
Arsênio , Poluentes do Solo , Arsênio/análise , Cádmio , Antimônio , Chumbo , Ouro , Areia , Disponibilidade Biológica , Poluentes do Solo/análise , Austrália , Solo , Mineração
10.
Environ Sci Technol ; 58(4): 1934-1943, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38180751

RESUMO

Antimony (Sb) biomethylation is an important but uninformed process in Sb biogeochemical cycling. Methylated Sb species have been widely detected in the environment, but the gene and enzyme for Sb methylation remain unknown. Here, we found that arsenite S-adenosylmethionine methyltransferase (ArsM) is able to catalyze Sb(III) methylation. The stepwise methylation by ArsM forms mono-, di-, and trimethylated Sb species. Sb(III) is readily coordinated with glutathione, forming the preferred ArsM substrate which is anchored on three conserved cysteines. Overexpressing arsM in Escherichia coli AW3110 conferred resistance to Sb(III) by converting intracellular Sb(III) into gaseous methylated species, serving as a detoxification process. Methylated Sb species were detected in paddy soil cultures, and phylogenetic analysis of ArsM showed its great diversity in ecosystems, suggesting a high metabolic potential for Sb(III) methylation in the environment. This study shows an undiscovered microbial process methylating aqueous Sb(III) into the gaseous phase, mobilizing Sb on a regional and even global scale as a re-emerging contaminant.


Assuntos
Arsênio , Arsenitos , Nostoc , Arsenitos/metabolismo , S-Adenosilmetionina/metabolismo , Antimônio , Arsênio/química , Nostoc/metabolismo , Ecossistema , Filogenia , Metiltransferases/química , Metiltransferases/genética , Metiltransferases/metabolismo
11.
Ecotoxicol Environ Saf ; 270: 115948, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38184976

RESUMO

The increasing production and prevalence of antimony (Sb)-related products raise concerns regarding its potential hazards to reproductive health. Upon environmental exposure, Sb reportedly induces testicular toxicity during spermatogenesis; moreover, it is known to affect various testicular cell populations, particularly germline stem cell populations. However, the cell-cell communication resulting from Sb exposure within the testicular niche remains poorly understood. To address this gap, herein we analyzed testicular single-cell RNA sequencing data from Sb-exposed Drosophila. Our findings revealed that the epidermal growth factor receptor (EGFR) and WNT signaling pathways were associated with the stem cell niche in Drosophila testes, which may disrupt the homeostasis of the testicular niche in Drosophila. Furthermore, we identified several ligand-receptor pairs, facilitating the elucidation of intercellular crosstalk involved in Sb-mediated reproductive toxicology. We employed scRNA-seq analysis and conducted functional verification to investigate the expression patterns of core downstream factors associated with EGFR and WNT signatures in the testes under the influence of Sb exposure. Altogether, our results shed light on the potential mechanisms of Sb exposure-mediated testicular cell-lineage communications.


Assuntos
Drosophila , Testículo , Masculino , Animais , Testículo/metabolismo , Drosophila/metabolismo , Antimônio/toxicidade , Antimônio/metabolismo , Comunicação Celular , Receptores ErbB/metabolismo , Análise de Sequência de RNA
12.
Int J Environ Health Res ; 34(4): 1977-1994, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37097044

RESUMO

In this study investigation of accumulations of critical raw materials (cobalt (Co), antimony (Sb), vanadium (V), lanthanum (La) and tungsten (W)) from wastewater by using C. fracta were aimed. Besides, assessment of the potential health risks in terms of the use of organic fertilizer obtained from the macroalga to be harvested from the treatment were also aimed. Highest Co, Sb, V, La and W accumulations by algae in reactor were 125±6.2%, 201.25±10%, 318.18±15%, 357.97±18%, and 500±25%, respectively. When compared with control, Co, Sb, V, La and W in algae increased 2.25, 3.01, 4.18, 4.58, and 6 times, respectively. The algae was very high bioaccumulative for Co and La. Highest MPI was calculated as 3.94. Non-carcinogenic risk of CRMs according to different exposure types (ingestion, inhalation, and dermal) were calculated for man, woman and child. There is not any non-carcinogenic risk from the investigated exposure ways of algae as organic fertilizer.


Assuntos
Fertilizantes , Águas Residuárias , Masculino , Criança , Feminino , Humanos , Águas Residuárias/toxicidade , Antimônio/análise , Tungstênio
13.
J Inorg Biochem ; 251: 112452, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38070433

RESUMO

Three gold(I) linear compounds, sharing the general formula [AuI(LPh3)], have been synthesized and characterized. The nature of the ligand has been modified by moving down among some of the elements of group 15, i.e. phosphorus, arsenic and antimony. The structures of derived compounds have been solved through XRD and the reactivity behaviour towards selected biomolecules has been investigated through a multi-technique approach involving NMR, high-resolution mass spectrometry and IR. Moreover, the biological activity of the investigated compounds has been comparatively analyzed through classical methodologies and the disclosed differences are discussed in detail.


Assuntos
Antineoplásicos , Auranofina , Auranofina/química , Antimônio/farmacologia , Ligantes , Antineoplásicos/farmacologia , Antineoplásicos/química
14.
J Biochem Mol Toxicol ; 38(1): e23548, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37867459

RESUMO

Four novel antimony (III) and bismuth(III) complexes of the kind Cl-Sb-O-C(OR)-CH(CH3 )C-NH-(CH2 )2 -NH-C(CH3 )CH:C(OR)-O [where R = -CH3 , M = Sb (1a); R = -C2 H5 , M = Sb (1b); R = -CH3, M = Bi (1c); R = -C2 H5 , M = Bi (1d)] were successfully prepared by reacting antimony(III)chloride and bismuth(III)chloride with sodium salt of ß-enamino esters in 1:1 stoichiometry, which were further structurally characterized by physicochemical and IR, 1 H, 13 C NMR spectral and mass spectrometry. Structural analysis revealed that all four derivatives of both antimony and bismuth display octahedarl geometry which has been optimized through computational studies. These derivatives along with their parent ligands were subsequently assayed in vitro for antibacterial (Bacillus subtilis, Pseudomonas aeruginosa) and antifungal (Aspergillus niger and Candida albicans) activities. Synthesized complexes were more efficacious in terms of biological activities as compared to parent ligands Further synthesized compounds were evaluated for their in vitro cytotoxic activity against lung cancer cell line A549 using MTT method. IC50 value for all four complexes was determined and all of them are found active. Computational studies of the representative complexes have been done using B3LYP/631-G* basis sets to provide optimized geometry.


Assuntos
Anti-Infecciosos , Antineoplásicos , Antimônio/farmacologia , Bismuto/farmacologia , Bismuto/química , Teoria da Densidade Funcional , Cloretos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Testes de Sensibilidade Microbiana
15.
Environ Sci Technol ; 58(1): 695-703, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38141021

RESUMO

The fate of antimony (Sb) is strongly affected by adsorption, yet Sb isotope fractionation and the associated mechanism have not been widely reported. Here we experimentally investigated the process of Sb(V) adsorption on iron (oxyhydr)oxides and the associated isotope effects. Sb isotope fractionation occurs during adsorption (Δ123Sbsolution-mineral = 1.20 ± 0.02‰ for ferrihydrite and 2.35 ± 0.04‰ for goethite). Extended X-ray absorption fine structure (EXAFS) analysis shows that Sb(V) adsorption on iron (oxyhydr)oxides occurs via inner-sphere surface complexation, including mononuclear bidentate edge-sharing (2E) and binuclear bidentate corner-sharing (2C) complexes. A longer atom distance of Sb-Fe in ferrihydrite leads to less Sb isotope fractionation during Sb adsorption than in goethite. The Gibbs free energy and Mayer bond order were calculated based on density functional theory (DFT) and suggested that the strength of the bonding environment can be summarized as Sb(OH)6- > 2E > 2C. In turn, the bonding environment indicates the mechanism of Sb isotope fractionation during the process. This study reveals that Sb isotope fractionation occurs during Sb(V) adsorption onto iron (oxyhydr)oxides, providing a basis for the future study of Sb isotopes and further understanding of the fractionation mechanism.


Assuntos
Ferro , Óxidos , Ferro/química , Antimônio/química , Adsorção , Compostos Férricos/química , Isótopos
16.
Wei Sheng Yan Jiu ; 52(6): 863-870, 2023 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-38115648

RESUMO

OBJECTIVE: To investigate the association between levels of twenty-three plasma metals/metalloids and the risk of arrhythmia among occupational population. METHODS: In 2017, a total of 765 workers aged 18 and above were recruited from a non-ferrous metal factory. The general demographic characteristics were obtained by using questionnaire. Plasma metal/metalloid levels were determined by inductively coupled plasma mass spectrometry(ICP-MS). Participants were followed up in 2018, 2019 and 2020 respectively. After the elements that may affect the incidence of arrhythmia were screened out by least absolute shrinkage and selection operator(LASSO) regression, Cox regression model was used to analyze the relationship between levels of selected elements and risk of arrhythmia occurrence, Quantile g-computation model was used to analyze the effect of element mixture exposure on arrhythmia, and the dose-response curve was estimated by using restricted cubic spline(RCS) function. RESULTS: Of all the research subjects, 386(50.5%) were ≤45 years old; 401(52.4%) had 20 years or more of work experience; 712(93.1%) subjects were male workers. The incidence of arrhythmia was 17.6%. After adjusting for age, seniority, gender, body mass index(BMI), marital status, education level, smoking, drinking, drinking tea, regular exercise, chronic diseases(hypertension, hyperlipidemia), sleep quality and psychological stress, chromium, molybdenum and antimony increased the risk of arrhythmia with HR(95%CI) values of 1.22(1.11-1.34), 1.51(1.20-1.90) and 2.38(1.03-5.49), respectively, while barium reduced the risk of arrhythmia with HR(95%CI) value of 0.98(0.95-1.00). CONCLUSION: Chromium, molybdenum and antimony are the risk factors while barium is the protective factor for arrhythmia.


Assuntos
Metaloides , Molibdênio , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Estudos Prospectivos , Antimônio , Bário , Metais , Cromo
17.
Toxicol Appl Pharmacol ; 480: 116746, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37931756

RESUMO

BACKGROUND: Cancers that primarily affect women in the US include breast, uterine, and cervical cancers. There may be associations between these different types of cancer in women and environmental pollutant exposure. PURPOSE: This study aimed to assess seven species of arsenic, six polycyclic aromatic hydrocarbon (PAH) compounds, and fourteen different metal concentrations in urine and their correlation with cancer among women. METHODS: We conducted a cross-sectional analysis using 2011--2012 to 2015-2016 National Health and Nutrition Examination Survey data (n = 4,956) and logistic regression modeling of the complex weighted survey design. RESULTS: Breast cancer was inversely correlated with arsenocholine (3rd quantile), monomethylarsonic acid (4th quantile), manganese (4th quantile), and antimony (3rd, 4th quantiles). Cervical cancer was inversely correlated with 3-hydroxyfluorene (3rd quantile), molybdenum (2nd, 4th quantiles), antimony (3rd quantile), tin (4th quantile), and thallium (4th quantile) exposure and positively associated with arsenic acid (3rd quantile), arsenobetaine (2nd, 4th quantiles). Uterine cancer was correlated with 1-hydroxynaphthalene (3rd, 4th quantiles), 2-hydroxynaphthalene (4th quantile), 1-hydroxyphenathrene (2nd, 4th quantiles), 1-hydroxypyrene (3rd quantile), cobalt (2nd, 3rd quantiles) and inversely with mercury (4th quantile). CONCLUSION: This study determined breast cancer and arsenic and some metal species exposure, indicating an inverse association. Arsenic acid and arsenobetaine exposure showed a positive correlation with cervical cancer. For uterine cancer, the correlations for the PAH compounds and cobalt showed a positive correlation, and the arsenic species and mercury were inversely associated. Further research is required to establish or refute the findings.


Assuntos
Arsênio , Neoplasias da Mama , Poluentes Ambientais , Mercúrio , Hidrocarbonetos Policíclicos Aromáticos , Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/induzido quimicamente , Neoplasias do Colo do Útero/epidemiologia , Antimônio , Inquéritos Nutricionais , Estudos Transversais , Metais , Poluentes Ambientais/urina , Cobalto , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/epidemiologia , Biomarcadores/urina
18.
ACS Sens ; 8(11): 4132-4142, 2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-37938135

RESUMO

Wearable gas sensors demonstrate broad potential for environmental monitoring and breath analysis applications. Typically, they require a highly stable and high-performance flexible gas sensing unit that can work with a small, flexible circuit to enable real-time accurate concentration analysis and prediction. This work proposes a flexible gas sensor using antimony-doped tin dioxide composite polyaniline as the sensing material for room-temperature ammonia detection over a wide humidity range. The sensor exhibits high sensitivity (response value at 33.1 toward 100 ppm ammonia at 70% relative humidity), excellent selectivity, and good long-term and mechanical stability. The increased sensitivity is due to a reduction in the hole concentration of polyaniline in air, achieved through compositing and doping. Subsequently, regression analysis equations are developed to establish the relationship between the gas concentration and sensor response under varying environmental humidity conditions. The sensor was integrated with a small, low-power circuit module to form a wearable smart bracelet with signal acquisition, processing, and wireless transmission functions, which could achieve early and remote warning of gas leakage in different humidity environments. This research demonstrates a promising approach to designing high-performance, high-stability, and flexible gas sensors and their corresponding wireless sensing systems.


Assuntos
Nanocompostos , Dispositivos Eletrônicos Vestíveis , Amônia/análise , Antimônio , Umidade
19.
Environ Int ; 181: 108269, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37866238

RESUMO

BACKGROUND: Limited evidence suggests that antimony induces vascular inflammation and oxidative stress and may play a role in cardiovascular disease (CVD) risk. However, few studies have examined whether environmental antimony from sources other than tobacco smoking is related with CVD risk. The general population may be exposed through air, drinking water, and food that contains antimony from natural and anthropogenic sources, such as mining, coal combustion, and manufacturing. OBJECTIVES: To examine the association of urine antimony with incident acute myocardial infarction (AMI), heart failure, and stroke among people who never smoked tobacco. METHODS: Between 1993 and 1997, the Danish Diet, Cancer and Health (DCH) cohort enrolled participants (ages 50-64 years), including n = 19,394 participants who reported never smoking at baseline. Among these never smokers, we identified incident cases of AMI (N = 809), heart failure (N = 958), and stroke (N = 534) using the Danish National Patient Registry. We also randomly selected a subcohort of 600 men and 600 women. We quantified urine antimony concentrations in samples provided at enrollment. We used modified Cox proportional hazards models to estimate adjusted hazard ratios (HR) for each incident CVD outcome in relation to urine antimony, statistically adjusted for creatinine. We used a separate prospective cohort, the San Luis Valley Diabetes Study (SLVDS), to replicate these results. RESULTS: In the DCH cohort, urine antimony concentrations were positively associated with rates of AMI and heart failure (HR = 1.52; 95%CI = 1.12, 2.08 and HR = 1.58; 95% CI = 1.15, 2.18, respectively, comparing participants in the highest (>0.09 µg/L) with the lowest quartile (<0.02 µg/L) of antimony). In the SLVDS cohort, urinary antimony was positively associated with AMI, but not heart failure. DISCUSSION: Among this sample of Danish people who never smoked, we found that low levels of urine antimony are associated with incident CVD. These results were partially confirmed in a smaller US cohort.


Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Infarto do Miocárdio , Acidente Vascular Cerebral , Feminino , Humanos , Masculino , Antimônio , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Dinamarca/epidemiologia , Infarto do Miocárdio/epidemiologia , não Fumantes , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Estudos Prospectivos
20.
Food Chem Toxicol ; 181: 114107, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37858840

RESUMO

Antimony (Sb) is a metalloid widely present in plastics used for food contact packaging, toys and other household items. Since Sb can be released by these plastics and come into contact with humans, health concerns have been highlighted. The effect of Sb on human tissues is yet controversial, and biochemical mechanisms of toxicity are lacking. In the present study, the effect of very low nanomolar concentrations of Sb(III), able to mimicking chronic human exposure, was evaluated in 3T3-L1 murine cells during the differentiation process. Low nanomolar Sb exposure (from 0.05 to 5 nM) induced lipid accumulation and a marked increase in C/EBP-ß and PPAR-γ levels, the master regulators of adipogenesis. The Sb-induced PPAR-γ was reverted by the estrogen receptor antagonist ICI 182,780. Additionally, Sb stimulated preadipocytes proliferation inducing G2/M phase of cell cycle and this effect was associated to reduced cell-cycle inhibitor p21 levels. In addition to these metabolic dysfunctions, Sb activated the proinflammatory NF-κB pathway and altered endoplasmic reticulum (ER) homeostasis inducing ROS increase, ER stress markers XBP-1s and pEIF2a and downstream genes, such as Grp78 and CHOP. This study, for the first time, supports obesogenic effects of low concentrations exposure of Sb during preadipocytes differentiation.


Assuntos
Adipogenia , Antimônio , Humanos , Animais , Camundongos , Células 3T3-L1 , Antimônio/toxicidade , Antimônio/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Adipócitos , Diferenciação Celular , Retículo Endoplasmático/metabolismo , Homeostase , PPAR gama/metabolismo
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