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1.
Sci Rep ; 14(1): 15074, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956098

RESUMEN

In our study, blood concentrations of lead (Pb), arsenic (As), and cadmium (Cd) and urine concentrations of thallium (Tl) were measured together with related symptoms of heavy metal poisoning in cigarette smoking volunteers diagnosed with schizophrenia, in cigarette smokers not diagnosed with schizophrenia, and in the control group of non-smokers and not diagnosed with schizophrenia volunteers. Our study was performed on 171 volunteers divided into the following subgroups: patients diagnosed with schizophrenia with at least 1 year of continuous cigarette smoking experience (56 participants), cigarette smokers not diagnosed with schizophrenia with at least one year of continuous smoking experience (58), and control group (not diagnosed with schizophrenia and non-smoking volunteers) (57). Smoking durations of cigarette smokers diagnosed with schizophrenia and cigarette smokers not diagnosed with schizophrenia are not similar (p = 0.431). Blood Pb, As, and Cd concentrations and urine Tl concentrations were the highest in the subgroup of cigarette smokers not diagnosed with schizophrenia, followed by the subgroup of cigarette smokers diagnosed with schizophrenia, and the control group. Only blood Pb concentrations were significantly higher (probability value p < 0.05) in the group of cigarette smokers not diagnosed with schizophrenia (5.16 µg/dL), comparing to the group of cigarette smokers diagnosed with schizophrenia (3.83 µg/dL) and to the control group (3.43 µg/dL). Blood Cd and As concentrations and urine Tl concentrations were significantly higher (p < 0.05) in cigarette smokers not diagnosed with schizophrenia than in the control group. The results revealed a statistically significant positive correlation (p < 0.001) in the cigarette smokers in the schizophrenia diagnosed group between blood Pb, blood As, and urine Tl concentrations and the duration of cigarette smoking.


Asunto(s)
Cadmio , Fumar Cigarrillos , Plomo , Esquizofrenia , Humanos , Esquizofrenia/sangre , Esquizofrenia/etiología , Masculino , Adulto , Femenino , Fumar Cigarrillos/efectos adversos , Fumar Cigarrillos/sangre , Plomo/sangre , Plomo/orina , Cadmio/sangre , Cadmio/orina , Persona de Mediana Edad , Metales Pesados/sangre , Metales Pesados/orina , Arsénico/sangre , Arsénico/orina , Talio/sangre , Talio/orina , Estudios de Casos y Controles
2.
J Environ Manage ; 365: 121524, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38897082

RESUMEN

Thallium (Tl) as a prominent priority contaminant in aquatic environment necessitates rigorous regulation. However, limited horizon devotes the impact of selective oxidation on the process of thallium purification. In this study, selective active radical of singlet oxygen (1O2) was continually generated for Tl(Ⅰ) oxidation accomplished with efficient Tl(Ⅲ) immobilization using iron-driven copper oxide (CuFe)/peroxymonosulfate (PMS). Fe-doping changed the active center of electronic structure for enhancing the catalytic and adsorptive reactivities, and installed magnetism for solid-liquid separation. Rapid reaction rate (0.253 min-1) coupled with vigorous elimination efficiency (98.32%) relied on electrostatic attraction, surface complexation, and H-bond interaction. EPR and XPS analyses demonstrated that the synergistic effects of ≡ Cu(Ⅰ)/≡Cu(Ⅱ) and ≡ Fe(Ⅲ)/≡Fe(Ⅱ) redounded to the sustained generation of 1O2 through the pathway of PMS → •O2- → 1O2, and 1O2 exploited an advantage to selectively oxidize Tl(Ⅰ) to Tl(Ⅲ). 3D isosurface cubic charts revealed that the immobilizing ability of Tl(Ⅲ) hydrate for CuFe was notably superior to that of Tl(Ⅲ) hydrate for CuO and Tl(Ⅰ) hydrate for CuO/CuFe, which further attested surface reactivity promoted stable immobilization form. This work develops the continuous generation of 1O2 and stable immobilization with the goal of efficiently cleansing Tl-containing wastewater.


Asunto(s)
Hierro , Oxígeno Singlete , Talio , Talio/química , Hierro/química , Oxígeno Singlete/química , Oxidación-Reducción , Cobre/química , Catálisis
3.
Nature ; 631(8020): 335-339, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38867053

RESUMEN

The initial rise of molecular oxygen (O2) shortly after the Archaean-Proterozoic transition 2.5 billion years ago was more complex than the single step-change once envisioned. Sulfur mass-independent fractionation records suggest that the rise of atmospheric O2 was oscillatory, with multiple returns to an anoxic state until perhaps 2.2 billion years ago1-3. Yet few constraints exist for contemporaneous marine oxygenation dynamics, precluding a holistic understanding of planetary oxygenation. Here we report thallium (Tl) isotope ratio and redox-sensitive element data for marine shales from the Transvaal Supergroup, South Africa. Synchronous with sulfur isotope evidence of atmospheric oxygenation in the same shales3, we found lower authigenic 205Tl/203Tl ratios indicative of widespread manganese oxide burial on an oxygenated seafloor and higher redox-sensitive element abundances consistent with expanded oxygenated waters. Both signatures disappear when the sulfur isotope data indicate a brief return to an anoxic atmospheric state. Our data connect recently identified atmospheric O2 dynamics on early Earth with the marine realm, marking an important turning point in Earth's redox history away from heterogeneous and highly localized 'oasis'-style oxygenation.


Asunto(s)
Atmósfera , Planeta Tierra , Oxígeno , Agua de Mar , Atmósfera/química , Sedimentos Geológicos/química , Historia Antigua , Océanos y Mares , Oxidación-Reducción , Oxígeno/análisis , Oxígeno/historia , Oxígeno/metabolismo , Agua de Mar/química , Sudáfrica , Isótopos de Azufre/análisis , Talio/análisis , Talio/química
4.
Plant Physiol Biochem ; 213: 108853, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38901231

RESUMEN

To reduce heavy metal toxicity, like that induced by thallium (TI) in plants, growth-promoting bacteria (GPB) are a widely used to enhance plant tolerance to heavy metals toxicity. In our study, we characterized seven GPB and identified Actinoplanes spp., as the most active strain. This bioactive strain was then applied to alleviate TI phytotoxicity. TI contamination (20 mg/kg soil) induced TI bioaccumulation, reducing wheat growth (biomass accumulation) and photosynthesis rate, by about 55% and 90%, respectively. TI stress also induced oxidative damages as indicated by increased oxidative markers (H2O2 and lipid peroxidation (MDA)). Interestingly, Actinoplanes spp. significantly reduced growth inhibition and oxidative stress by 20% and 70%, respectively. As a defense mechanism to mitigate the TI toxicity, wheat plants showed improved antioxidant and detoxification defense including increased phenolic and tocopherols levels as well as peroxidase (POX), catalase (CAT), superoxide dismutase (SOD), and glutathione reductase (GR) enzymes activities. These defense mechanisms were further induced by Actinoplanes spp. Additionally, Actinoplanes spp. increased the production of heavy metal-binding ligands such as metallothionein, phytochelatins, total glutathione, and glutathione S-transferase activity by 100%, 90%, 120%, and 100%, respectively. This study, therefore, elucidated the physiological and biochemical bases underlying TI-stress mitigation impact of Actinoplanes spp. Overall, Actinoplanes spp. holds promise as a valuable approach for ameliorating TI toxicity in plants. KEYBOARD: Actinobacteria, Bioaccumulation, Detoxification, Membrane damage, Redox regulation.


Asunto(s)
Estrés Oxidativo , Talio , Triticum , Triticum/efectos de los fármacos , Triticum/metabolismo , Estrés Oxidativo/efectos de los fármacos , Talio/metabolismo , Talio/toxicidad , Peroxidación de Lípido/efectos de los fármacos , Antioxidantes/metabolismo , Peróxido de Hidrógeno/metabolismo , Fotosíntesis/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Catalasa/metabolismo
5.
Methods Mol Biol ; 2796: 97-103, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38856897

RESUMEN

The development of cell-based fluorescent assays has resulted in an incredible tool for searching new ion channels' modulators with a biophysical and clinical profile. Among all the ion channels, potassium (K+)-permeable channels represent the most diverse and relevant for cell function, making them attractive targets for drug discovery. Some of the cell-based assays for K+ channels take advantage of a thallium-sensitive dye whose fluorescence increased upon the binding of thallium (Tl+), an ion able to move through K+ channels. We optimize the FLIPR Potassium Assay Kit based on thallium influx to measure the Kv10.1 activity.


Asunto(s)
Talio , Talio/metabolismo , Humanos , Colorantes Fluorescentes/química , Células HEK293 , Fluorescencia , Canales de Potasio Éter-A-Go-Go
6.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38731969

RESUMEN

This review offers a synthesis of the current understanding of the impact of low-dose thallium (Tl) on public health, specifically emphasizing its diverse effects on various populations and organs. The article integrates insights into the cytotoxic effects, genotoxic potential, and molecular mechanisms of thallium in mammalian cells. Thallium, a non-essential heavy metal present in up to 89 different minerals, has garnered attention due to its adverse effects on human health. As technology and metallurgical industries advance, various forms of thallium, including dust, vapor, and wastewater, can contaminate the environment, extending to the surrounding air, water sources, and soil. Moreover, the metal has been identified in beverages, tobacco, and vegetables, highlighting its pervasive presence in a wide array of food sources. Epidemiological findings underscore associations between thallium exposure and critical health aspects such as kidney function, pregnancy outcomes, smoking-related implications, and potential links to autism spectrum disorder. Thallium primarily exerts cellular toxicity on various tissues through mitochondria-mediated oxidative stress and endoplasmic reticulum stress. This synthesis aims to shed light on the intricate web of thallium exposure and its potential implications for public health, emphasizing the need for vigilant consideration of its risks.


Asunto(s)
Salud Pública , Talio , Humanos , Talio/toxicidad , Animales , Exposición a Riesgos Ambientales/efectos adversos , Estrés Oxidativo/efectos de los fármacos
7.
Ecotoxicol Environ Saf ; 279: 116470, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38772147

RESUMEN

Several studies have suggested an association between exposure to various metals and the onset of type 2 diabetes (T2D). However, the results vary across different studies. We aimed to investigate the associations between serum metal concentrations and the risk of developing T2D among 8734 participants using a prospective cohort study design. We utilized inductively coupled plasmamass spectrometry (ICP-MS) to assess the serum concentrations of 27 metals. Cox regression was applied to calculate the hazard ratios (HRs) for the associations between serum metal concentrations on the risk of developing T2D. Additionally, 196 incident T2D cases and 208 healthy control participants were randomly selected for serum metabolite measurement using an untargeted metabolomics approach to evaluate the mediating role of serum metabolite in the relationship between serum metal concentrations and the risk of developing T2D with a nested casecontrol study design. In the cohort study, after Bonferroni correction, the serum concentrations of zinc (Zn), mercury (Hg), and thallium (Tl) were positively associated with the risk of developing T2D, whereas the serum concentrations of manganese (Mn), molybdenum (Mo), barium (Ba), lutetium (Lu), and lead (Pb) were negatively associated with the risk of developing T2D. After adding these eight metals, the predictive ability increased significantly compared with that of the traditional clinical model (AUC: 0.791 vs. 0.772, P=8.85×10-5). In the nested casecontrol study, a machine learning analysis revealed that the serum concentrations of 14 out of 1579 detected metabolites were associated with the risk of developing T2D. According to generalized linear regression models, 7 of these metabolites were significantly associated with the serum concentrations of the identified metals. The mediation analysis showed that two metabolites (2-methyl-1,2-dihydrophthalazin-1-one and mestranol) mediated 46.81% and 58.70%, respectively, of the association between the serum Pb concentration and the risk of developing T2D. Our study suggested that serum Mn, Zn, Mo, Ba, Lu, Hg, Tl, and Pb were associated with T2D risk. Two metabolites mediated the associations between the serum Pb concentration and the risk of developing T2D.


Asunto(s)
Diabetes Mellitus Tipo 2 , Metales , Humanos , Diabetes Mellitus Tipo 2/sangre , Estudios Prospectivos , Masculino , Femenino , Persona de Mediana Edad , China , Metales/sangre , Adulto , Anciano , Contaminantes Ambientales/sangre , Estudios de Cohortes , Metabolómica , Estudios de Casos y Controles , Talio/sangre , Exposición a Riesgos Ambientales/estadística & datos numéricos , Pueblos del Este de Asia
8.
Artículo en Inglés | MEDLINE | ID: mdl-38781478

RESUMEN

Dietary supplements are drastically growing as a category of consumer products all over the world. The abuse of supplements marketed for slimming purposes and physical fitness has been observed worldwide in recent years, which raises concerns in terms of public health. In this study, different types of dietary supplements marketed and delivered through the e-commerce were studied for the determination of thallium as a hazardous inorganic contaminant. The total content of thallium was determined by a sensitive voltammetric method after a microwave-assisted oxidative digestion of the sample. In addition, a comparative spectrometric method was applied for validation of the results in the samples. The maximum concentration found for thallium was found to be 2.89 mg kg-1, which well agree with the comparative measurement. Considering the 32 studied formulations, it can be pointed out that ∼24% of the of dietary supplements presented Tl concentrations at concentrations higher than 1 mg kg-1. The results permitted the assessment of the health risk related to thallium from contaminated samples, based on the calculation of the estimated daily intake (EDI) and the risk quotient (HQ). The highest daily intake of thallium was calculated as 82.0 µg day-1 in a protein-based supplement, which is equivalent to an EDI of 1.17 µg kg-1 day-1. This work highlights the need to develop regulations on the limits of toxic elements such as thallium in widely consumed dietary supplements, as well as an in-depth look at the adverse effects caused by this element in the human body.


Asunto(s)
Suplementos Dietéticos , Contaminación de Alimentos , Talio , Pérdida de Peso , Talio/análisis , Suplementos Dietéticos/análisis , Humanos , Contaminación de Alimentos/análisis
9.
Org Biomol Chem ; 22(23): 4748-4756, 2024 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-38804097

RESUMEN

Ion channels are essential proteins for all organisms. Electrophysiology is a useful and commonly employed method to study ion channels, however there is a need for operationally simpler, cost-effective and higher throughput techniques to study ion channel functions in their native environments. Fluorescent ion indicators, such as Fluo-4 and Thallos, have been used for decades to study ion channel activity by measuring the flux of ions through channels of interest. In this work, we present ION Thallos-HTL, a thallium indicator that can be localized using HaloTag technology. This novel indicator enables specific labeling of cells and intracellular compartments in live cells and responds to changes in thallium concentration within these environments. We demonstrate the utility of ION Thallos-HTL by conducting a thallium flux assay using high-throughput instrumentation in a mixed cell population where some cells are expressing HaloTag and some are not.


Asunto(s)
Colorantes Fluorescentes , Talio , Talio/química , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Humanos , Células HEK293 , Canales Iónicos/metabolismo , Estructura Molecular
10.
Environ Sci Technol ; 58(19): 8510-8517, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38695484

RESUMEN

Anthropogenic activities have fundamentally changed the chemistry of the Baltic Sea. According to results reported in this study, not even the thallium (Tl) isotope cycle is immune to these activities. In the anoxic and sulfidic ("euxinic") East Gotland Basin today, Tl and its two stable isotopes are cycled between waters and sediments as predicted based on studies of other redox-stratified basins (e.g., the Black Sea and Cariaco Trench). The Baltic seawater Tl isotope composition (ε205Tl) is, however, higher than predicted based on the results of conservative mixing calculations. Data from a short sediment core from East Gotland Basin demonstrates that this high seawater ε205Tl value originated sometime between about 1940 and 1947 CE, around the same time other prominent anthropogenic signatures begin to appear in the same core. This juxtaposition is unlikely to be coincidental and suggests that human activities in the surrounding area have altered the seawater Tl isotope mass-balance of the Baltic Sea.


Asunto(s)
Sedimentos Geológicos , Océanos y Mares , Agua de Mar , Talio , Agua de Mar/química , Sedimentos Geológicos/química , Actividades Humanas , Humanos , Monitoreo del Ambiente , Contaminantes Químicos del Agua , Isótopos
11.
Chemosphere ; 358: 142201, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38692367

RESUMEN

Thallium (Tl) is a potential toxicity element that poses significant ecological and environmental risks. Recently, a substantial amount of Tl has been released into the environment through natural and human activities, which attracts increasing attention. The determination of this hazardous and trace element is crucial for controlling its pollution. This article summarizes the advancement and progress in optimizing Tl detection techniques, including atomic absorption spectroscopy (AAS), voltammetry, inductively coupled plasma (ICP)-based methods, spectrophotometry, and X-ray-based methods. Additionally, it introduces sampling and pretreatment methods such as diffusive gradients in thin films (DGT), liquid-liquid extraction, solid phase extraction, and cloud point extraction. Among these techniques, ICP-mass spectrometry (MS) is the preferred choice for Tl detection due to its high precision in determining Tl as well as its species and isotopic composition. Meanwhile, some new materials and agents are employed in detection. The application of novel work electrode materials and chromogenic agents is discussed. Emphasis is placed on reducing solvent consumption and utilizing pretreatment techniques such as ultrasound-assisted processes and functionalized magnetic particles. Most detection is performed in aqueous matrices, while X-ray-based methods applied to solid phases are summarized which provide non-destructive analysis. This work improves the understanding of Tl determination technology while serving as a valuable resource for researchers seeking appropriate analytical techniques.


Asunto(s)
Monitoreo del Ambiente , Talio , Talio/análisis , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Espectrofotometría Atómica , Extracción en Fase Sólida/métodos , Espectrometría de Masas/métodos , Extracción Líquido-Líquido/métodos
12.
J AOAC Int ; 107(4): 632-640, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38565261

RESUMEN

BACKGROUND: An interlaboratory study was conducted at the U.S. Food and Drug Administration's (FDA) Northeast Food and Feed Laboratory (NFFL) and the Center for Food Safety and Applied Nutrition (CFSAN) with the purpose to expand FDA Elemental Analysis Manual (EAM) method 4.7 (Inductively Coupled Plasma-Mass Spectrometric Determination of Arsenic, Cadmium, Chromium, Lead, Mercury, and Other Elements in Food Using Microwave Assisted Digestion) to include new analytes. OBJECTIVE: The goal of the study was to demonstrate the performance of FDA EAM method 4.7 when analyzing new analytes cobalt (Co), strontium (Sr), thallium (Tl), tin (Sn), uranium (U), and vanadium (V). This analyte extension method validation of EAM 4.7 for six additional elements, Co, Sr, Tl, Sn, U, and V, followed all guidelines for a Level 2 or single-laboratory validation and met all acceptance criteria for analyte extensions as per the Guidelines for the Validation of Chemical Methods. METHOD: As per EAM 4.7, this study followed the procedures and used specified equipment operated under recommended conditions. The analyte extension method validation was performed in accordance with protocol and with no deviations. RESULTS: All quality control (QC) requirements for this analyte extension method validation of EAM 4.7 passed as evidenced by the analytical data. The results presented demonstrate accuracy, linearity, and precision by successful analyses of method blanks, matrix spikes, unfortified test samples, and reference materials. The data analyzed met each of the validation requirements for each analyte in all representative matrixes. CONCLUSIONS: The study showed that the new analytes performed satisfactorily using EAM 4.7 for total acidic extractable elemental analysis of food according to FDA's guidelines. HIGHLIGHTS: The method met or exceeded the performance criteria.


Asunto(s)
Cobalto , Estroncio , Talio , Estaño , Uranio , Cobalto/análisis , Talio/análisis , Uranio/análisis , Estaño/análisis , Estroncio/análisis , Vanadio/análisis , Análisis de los Alimentos/métodos , Espectrometría de Masas/métodos , Estados Unidos , United States Food and Drug Administration
13.
Arch Toxicol ; 98(7): 2085-2100, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38619592

RESUMEN

Thallium (Tl) and its two cationic species, Tl(I) and Tl(III), are toxic for most living beings. In this work, we investigated the effects of Tl (10-100 µM) on the viability and proliferation capacity of the adherent variant of PC12 cells (PC12 Adh cells). While both Tl(I) and Tl(III) halted cell proliferation from 24 h of incubation, their viability was ~ 90% even after 72 h of treatment. At 24 h, increased levels of γH2AX indicated the presence of DNA double-strand breaks. Simultaneously, increased expression of p53 and its phosphorylation at Ser15 were observed, which were associated with decreased levels of p-AKTSer473 and p-mTORSer2448. At 72 h, the presence of large cytoplasmic vacuoles together with increased autophagy predictor values suggested that Tl may induce autophagy in these cells. This hypothesis was corroborated by images obtained by transmission electron microscopy (TEM) and from the decreased expression at 72 h of incubation of SQSTM-1 and increased LC3ß-II to LC3ß-I ratio. TEM images also showed enlarged ER that, together with the increased expression of IRE1-α from 48 h of incubation, indicated that Tl-induced ER stress preceded autophagy. The inhibition of autophagy flux with chloroquine increased cell mortality, suggesting that autophagy played a cytoprotective role in Tl toxicity in these cells. Together, results indicate that Tl(I) or Tl(III) are genotoxic to PC12 Adh cells which respond to the cations inducing ER stress and cytoprotective autophagy.


Asunto(s)
Autofagia , Proliferación Celular , Supervivencia Celular , Estrés del Retículo Endoplásmico , Talio , Autofagia/efectos de los fármacos , Células PC12 , Animales , Ratas , Estrés del Retículo Endoplásmico/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Talio/toxicidad , Proliferación Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Roturas del ADN de Doble Cadena/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Fosforilación , Microscopía Electrónica de Transmisión
14.
Ecotoxicol Environ Saf ; 276: 116290, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599154

RESUMEN

Thallium (Tl) is a non-essential metal mobilized through industrial processes which can lead to it entering the environment and exerting toxic effects. Plants are fundamental components of all ecosystems. Therefore, understanding the impact of Tl on plant growth and development is of great importance for assessing the potential environmental risks of Tl. Here, the responses of Arabidopsis thaliana to Tl were elucidated using physiological, genetic, and transcriptome analyses. Thallium can be absorbed by plant roots and translocated to the aerial parts, accumulating at comparable concentrations throughout plant parts. Genetic evidence supported the regulation of Tl uptake and movement by different molecular compartments within plants. Thallium primarily caused growth inhibition, oxidative stress, leaf chlorosis, and the impairment of K homeostasis. The disturbance of redox balance toward oxidative stress was supported by significant differences in the expression of genes involved in oxidative stress and antioxidant defense under Tl exposure. Reduced GSH levels in cad2-1 mutant rendered plants highly sensitive to Tl, suggesting that GSH has a prominent role in alleviating Tl-triggered oxidative responses. Thallium down-regulation of the expression of LCHII-related genes is believed to be responsible for leaf chlorosis. These findings illuminate some of the mechanisms underlying Tl toxicity at the physiological and molecular levels in plants with an eye toward the future environment management of this heavy metal.


Asunto(s)
Arabidopsis , Estrés Oxidativo , Talio , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Talio/toxicidad , Estrés Oxidativo/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Contaminantes del Suelo/toxicidad
15.
Sci Total Environ ; 927: 172294, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38593882

RESUMEN

Biochar colloids entering the soil undergo aging over time and exhibit strong capabilities in adsorbing and transporting pollutants. Therefore, investigating the cotransport of aged biochar colloids and thallium (Tl(I)) in quartz sand media is crucial for understanding Tl(I) migration in underground environments. This study investigated the migration of biochar colloids with two different aging degrees and Tl(I) in quartz sand media at various pH and ionic strengths (ISs). The results revealed that under all ISs and pH, 30%AWB (biochar aged with 30 % (w/w) HNO3) inhibited Tl(I) migration in media. This inhibition primarily arose from the introduction of hydroxyl and carboxyl groups during aging, which significantly enhanced colloid adsorption onto Tl(I). At lower ISs, 30%AWB colloids exhibited greater inhibition of Tl(I) migration due to their increased adsorption capacity. Additionally, aging promoted the migration of biochar colloids in the media. Greater biochar aging notably enhanced this promotion, potentially owing to reduced colloidal particle size and the formation of biochar derivatives. Moreover, 50%AWB (biochar aged with 50 % (w/w) HNO3) inhibited Tl(I) migration under low ISs but had almost no impact under high ISs. Nonetheless, at high pH, 50%AWB colloids facilitated Tl(I) migration. This phenomenon might be attributed to the inhibitory effect of aged biochar colloids on Tl(I) adsorption onto media at a high pH, as well as the stable binding between Tl(I) and aged biochar colloids. This study discusses the cotransport of biochar with various degrees of aging and Tl(I) in media, providing insights into remediating soils contaminated with Tl.


Asunto(s)
Carbón Orgánico , Coloides , Talio , Carbón Orgánico/química , Concentración de Iones de Hidrógeno , Coloides/química , Concentración Osmolar , Adsorción , Porosidad , Modelos Químicos
16.
Phys Med Biol ; 69(11)2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38657638

RESUMEN

Objective. Prompt gamma timing (PGT) uses the detection time of prompt gammas emitted along the range of protons in proton radiotherapy to verify the position of the Bragg peak (BP). Cherenkov detectors offer the possibility of enhanced signal-to-noise ratio (SNR) due to the inherent physics of Cherenkov emission which enhances detection of high energy prompt gamma rays relative to other induced uncorrelated signals. In this work, the PGT technique was applied to 3 semiconductor material slabs that emit only Cherenkov light for use in a full scale system: a 3 × 3 × 20 mm3TlBr, a 12 × 12 × 12 mm3TlBr, and a 5 × 5 × 5 mm3TlCl.Approach. A polymethyl methacrylate (PMMA) target was exposed to a 67.5 MeV, 0.5 nA proton beam and shifted in 3 mm increments at the Crocker nuclear laboratory (CNL) in Davis, CA, USA. A fast plastic scintillator coupled to a photomultiplier tube (PMT) provided the start reference for the proton time of flight. Time of flight (TOF) distributions were generated using this reference and the gamma-ray timestamp in the Cherenkov detector.Main results. The SNR of the proton correlated peaks relative to the background was 20, 29, and 30 for each of the three samples, respectively. The upper limit of the position resolutions with the TlCl sample were 2 mm, 3 mm, and 5 mm for 30k, 10k, and 5k detected events, respectively. The time distribution of events with respect to the reference reproduced with clarity the periodicity of the beam, implying a very high SNR of the Cherenkov crystals to detect prompt gammas. Background presence from the neutron-induced continuum, prompt gammas from deuterium, or positron activation were not observed. Material choice and crystal dimensions did not seem to affect significantly the outcome of the results.Significance. These results show the high SNR of the pure Cherenkov emitters TlBr and TlCl for the detection of prompt gammas in a proton beam with current of clinical significance and their potential for verifying the proton range. The accuracy in determining shifts of the BP was highly dependent on the number of events acquired, therefore, the performance of these detectors are expected to vary with different beam conditions such as current, pulse repetition, and proton bunch width.


Asunto(s)
Rayos gamma , Terapia de Protones , Factores de Tiempo , Terapia de Protones/instrumentación , Talio , Lutecio/química , Protones , Polimetil Metacrilato/química
17.
Wei Sheng Yan Jiu ; 53(2): 294-299, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-38604967

RESUMEN

OBJECTIVE: To establish an analytical method for determining the migration of 24 elements in Yixing clay pottery in 4% acetic acid simulated solution by inductively coupled plasma mass spectrometry. METHODS: Four types of Yixing clay pottery, including Yixing clay teapot, Yixing clay kettle, Yixing clay pot, and Yixing clay electric stew pot, were immersed in 4% acetic acid as a food simulant for testing. The migration amount of 24 elements in the migration solution was determined using inductively coupled plasma mass spectrometry. RESULTS: Lithium, magnesium, aluminum, iron, and barium elements with a mass concentration of 1000 µg/L; Lead, cadmium, total arsenic, chromium, nickel, copper, vanadium, manganese, antimony, tin, zinc, cobalt, molybdenum, silver, beryllium, thallium, titanium, and strontium elements within 100 µg/L there was a linear relationship within, the r value was between 0.998 739 and 0.999 989. Total mercury at 5.0 µg/L, there was a linear relationship within, the r value of 0.995 056. The detection limit of the elements measured by this method was between 0.5 and 45.0 µg/L, the recovery rate was 80.6%-108.9%, and the relative standard deviation was 1.0%-4.8%(n=6). A total of 32 samples of four types of Yixing clay pottery sold on the market, including teapots, boiling kettles, casseroles, and electric stewing pots, were tested. It was found that the migration of 16 elements, including beryllium, titanium, chromium, nickel, cobalt, zinc, silver, cadmium, antimony, total mercury, thallium, tin, copper, total arsenic, molybdenum, and lead, were lower than the quantitative limit. The element with the highest migration volume teapot was aluminum, magnesium, and barium; The kettle was aluminum and magnesium; Casserole was aluminum, magnesium, and lithium; The electric stew pot was aluminum. CONCLUSION: This method is easy to operate and has high accuracy, providing an effective and feasible detection method for the determination and evaluation of element migration in Yixing clay pottery.


Asunto(s)
Arsénico , Mercurio , Oligoelementos , Acetatos , Aluminio/análisis , Antimonio/análisis , Arsénico/análisis , Bario/análisis , Berilio/análisis , Cadmio/análisis , Cromo , Arcilla , Cobalto/análisis , Cobre , Litio/análisis , Magnesio , Espectrometría de Masas , Mercurio/análisis , Molibdeno/análisis , Níquel , Plata/análisis , Talio/análisis , Estaño/análisis , Titanio/análisis , Oligoelementos/análisis , Zinc , China
18.
Wei Sheng Yan Jiu ; 53(2): 267-274, 2024 Mar.
Artículo en Chino | MEDLINE | ID: mdl-38604963

RESUMEN

OBJECTIVE: To investigate the association of metals/metalloids exposure with risk of liver disfunction among occupational population in Hunan Province, and to explore the potential dose-response relationship. METHODS: In 2017, a mining area in Hunan Province was chosen as the research site, and eligible workers were recruited as study subjects. General demographic characteristics, levels of 23 metals/metalloids in plasma and urine, and liver function index(total bilirubin(TBIL), alanine amino transferase(ALT), globulin(GLB) and γ-glutamyl transferase(GGT)) were obtained by questionnaire, physical examination and laboratory tests. Participants were followed up in 2018, 2019 and 2020 respectively. Cox proportional risk model was used to evaluate the relationship between metal/metalloids exposure and risk of liver disfunction, and dose-response relationship curves were plotted by using the restricted cubic spline function. RESULTS: A total of 891 employees were recruited in the study, 576(65.0%)were aged ≤45 years, 832(93.4%) were male and 530(59.5%) worked as smelters. After adjusting various factors such as age, gender, BMI, type of work, education, smoking, alcohol consumption, diet, stress, medical history, exercise and tea consumption, positive correlations were found between plasma tungsten(HR=4.90, 95%CI 1.17-20.48) and urinary barium(HR=1.07, 95%CI 1.02-1.12) levels with abnormally elevated TBIL levels. Additionally, a significant association was observed between plasma thallium and the risk of elevated ALT levels(HR=11.15, 95%CI 1.97-63.29). CONCLUSION: Plasma tungsten and thallium, along with barium found in urine, are risk factors for the development of abnormally elevated liver function indices in occupational groups.


Asunto(s)
Hepatopatías , Metaloides , Humanos , Masculino , Femenino , Estudios Prospectivos , Talio , Bario , Tungsteno , Metales
19.
Medicine (Baltimore) ; 103(9): e37317, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38428895

RESUMEN

To evaluate the correlation between thallium and diabetes risk among participants with hearing loss. This retrospective cohort study extracted related data such as demographic characteristics, lifestyle factors, and laboratory findings from the National Health and Nutrition Examination Survey (NHANES) database (2013-2018). Logistic regression analysis and interaction analysis were adopted to analyze the correlation between thallium and diabetes risk among patients with hearing loss. Then, the restricted cubic spline was employed to assess the nonlinear relationship between thallium and diabetes risk. The receiver operating characteristic curve and decision curve analysis were used to assess the predictive values of 3 multivariate models with or without thallium for diabetes risk. The Delong test was adopted to assess the significant change of the area under the curves (AUCs) upon thallium addition. A total of 425 participants with hearing loss were enrolled in the study: without diabetes group (n = 316) and diabetes group (n = 109). Patients with hearing loss in the diabetes group had significantly lower thallium (P < .05). The thallium was an independent predictor for diabetes risk after adjusting various covariates (P < .05). The restricted cubic spline (RCS) result showed that there was a linear correlation between thallium and diabetes risk (P nonlinear > .05). Finally, the receiver operating characteristic and decision curve analysis results revealed that adding thallium to the models slightly increased the performance in predicting diabetes risk but without significance in AUC change. Thallium was an independent predictor of diabetes risk among patients with hearing loss. The addition of thallium might help improve the predictive ability of models for risk reclassification. However, the conclusions should be verified in our cohort in the future due to the limitations inherent in the NHANES database.


Asunto(s)
Sordera , Diabetes Mellitus , Pérdida Auditiva , Humanos , Encuestas Nutricionales , Talio , Estudios Retrospectivos , Pérdida Auditiva/epidemiología , Pérdida Auditiva/etiología , Diabetes Mellitus/epidemiología
20.
Environ Pollut ; 347: 123711, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38447654

RESUMEN

Nano-scale Mn oxides can act as effective stabilizers for Tl in soil and sediments. Nevertheless, the comprehensive analysis of the capacity of MnO2 to immobilize Tl in such porous media has not been systematically explored. Therefore, this study investigates the impact of γ-MnO2, a model functional nanomaterial for remediation, on the mobility of Tl in a water-saturated quartz sand-packed column. The mechanisms involved are further elucidated based on the adsorption and aggregation kinetics of γ-MnO2. The results indicate that higher ionic strength (IS) and the presence of ion Ca(II) promote the aggregation of γ-MnO2, resulting from the reduced electrostatic repulsion between particles. Conversely, an increase in pH inhibits aggregation due to enhanced interaction energy. γ-MnO2 significantly influences Tl retention and mobility, with a substantial fraction of γ-MnO2-bound Tl transported through the column. This might be attributed to the high affinity of γ-MnO2 for Tl through ion exchange reactions and precipitation at the surface of γ-MnO2. The mobility of Tl in the sand column is influenced by the γ-MnO2 colloids, exhibiting either inhibition or promotion depending on the pH, IS, and cation type of the solution. In solutions with higher IS and Ca(II), the mobility of Tl decreases as γ-MnO2 colloids tend to aggregate, strain, and block, facilitating colloidal Tl retention in porous media. Although higher pH reduces the mobility of individual Tl, it promotes the mobility of γ-MnO2 colloids, facilitating a substantial fraction of colloidal-form Tl. Consequently, the optimal conditions for stabilizing Tl by γ-MnO2 involve either high IS and low pH or the presence of competitive cations (e.g., Ca(II)). These findings provide new insights into Tl immobilization using MnO2- and Mn oxide-based functional materials, offering potential applications in the remediation of Tl contamination in soil and groundwater.


Asunto(s)
Nanopartículas , Agua , Óxidos , Arena , Talio , Porosidad , Compuestos de Manganeso , Coloides , Suelo
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