RESUMEN
The arsenic (As) release from sediments in great lakes is affected by various factors. In this study, the characteristics of As release from sediments was investigated, and the As sources and sinks with the strengths in sediments from different areas (grass-type, algae-type, and grass-algae alternation areas) in great shallow lakes (Taihu Lake, China) were analyzed, and the influence of P competition in the process of As release was also studied. The results showed that changing trend of the values of equilibrium As concentration in sediments were consistent with the regional changes (0 to 28.12 µg/L), and the sediments from algae-type areas had the higher values. The sediments from western lake and northwest lake bay were a strong As and a weak P source, and the north lake bay had the opposite trend of these two regions. Intense P source competition with As from the sediments occurred in algae-type areas. The grass-type areas had strong As and P retention capacities, indicating a sink role of sediment with high As and P sorption capacities. The degree of As and P saturation had similar trend in sediments, and the grass-type areas had the higher values, 18.3%-21.4% and 15.31%-20.34%, respectively. Contribution analysis results showed that most of As release contribution was from the bottom (30-50 cm) sediments, and the surface (0-10 cm) sediments from algae-type areas contributed more to the overlying water than other region.
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Arsénico , Monitoreo del Ambiente , Sedimentos Geológicos , Lagos , Fósforo , Contaminantes Químicos del Agua , Lagos/química , Fósforo/análisis , Arsénico/análisis , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , China , PoaceaeRESUMEN
Arsenic (As) methylation in soils affects the environmental behavior of As, excessive accumulation of dimethylarsenate (DMA) in rice plants leads to straighthead disease and a serious drop in crop yield. Understanding the mobility and transformation of methylated arsenic in redox-changing paddy fields is crucial for food security. Here, soils including un-arsenic contaminated (N-As), low-arsenic (L-As), medium-arsenic (M-As), and high-arsenic (H-As) soils were incubated under continuous anoxic, continuous oxic, and consecutive anoxic/oxic treatments respectively, to profile arsenic methylating process and microbial species involved in the As cycle. Under anoxic-oxic (A-O) treatment, methylated arsenic was significantly increased once oxygen was introduced into the incubation system. The methylated arsenic concentrations were up to 2-24 times higher than those in anoxic (A), oxic (O), and oxic-anoxic (O-A) treatments, under which arsenic was methylated slightly and then decreased in all four As concentration soils. In fact, the most plentiful arsenite S-adenosylmethionine methyltransferase genes (arsM) contributed to the increase in As methylation. Proteobacteria (40.8%-62.4%), Firmicutes (3.5%-15.7%), and Desulfobacterota (5.3%-13.3%) were the major microorganisms related to this process. These microbial increased markedly and played more important roles after oxygen was introduced, indicating that they were potential keystone microbial groups for As methylation in the alternating anoxic (flooding) and oxic (drainage) environment. The novel findings provided new insights into the reoxidation-driven arsenic methylation processes and the model could be used for further risk estimation in periodically flooded paddy fields.
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Arsénico , Oryza , Microbiología del Suelo , Contaminantes del Suelo , Suelo , Arsénico/análisis , Contaminantes del Suelo/análisis , Metilación , Suelo/química , Microbiota , Oxidación-Reducción , Bacterias/metabolismoRESUMEN
In this study, we investigated improving the performance of a layered double hydroxide (LDH) for the adsorption of As(III) and As(V) by controlling the morphology of LDH crystals. The LDH was synthesized via a simple coprecipitation method using barely soluble MgO as a precursor and succinic acid (SA) as a morphological control agent. Doping the LDH crystals with carboxylate ions (RCOO-) derived from SA caused the crystals to develop in a radial direction. This changed the pore characteristics and increased the density of active surface sites. Subsequently, SA/MgFe-LDH showed excellent affinity for As(III) and As(V) with maximum sorption densities of 2.42 and 1.60 mmol/g, respectively. By comparison, the pristine MgFe-LDH had sorption capacities of 1.56 and 1.31 mmol/g for As(III) and As(V), respectively. The LDH was effective over a wide pH range for As(III) adsorption (pH 3-8.5) and As(V) adsorption (pH 3-6.5). Using a combination of spectroscopy and sorption modeling calculations, the main sorption mechanism of As(III) and As(V) on SA/MgFe-LDH was identified as inner-sphere complexation via ligand exchange with hydroxyl group (-OH) and RCOO-. Specifically, bidentate As-Fe complexes were proposed for both As(III) and As(V) uptake, with the magnitude of formation varying with the initial As concentration. Importantly, the As-laden adsorbent had satisfactory stability in simulated real landfill leachate. These findings demonstrate that SA/MgFe-LDH exhibits considerable potential for remediation of As-contaminated water.
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Arsénico , Hidróxidos , Óxido de Magnesio , Ácido Succínico , Contaminantes Químicos del Agua , Adsorción , Contaminantes Químicos del Agua/química , Cinética , Arsénico/química , Ácido Succínico/química , Hidróxidos/química , Óxido de Magnesio/química , Purificación del Agua/métodos , Modelos QuímicosRESUMEN
Arsenic (As) pollution in soils is a pervasive environmental issue. Biochar immobilization offers a promising solution for addressing soil As contamination. The efficiency of biochar in immobilizing As in soils primarily hinges on the characteristics of both the soil and the biochar. However, the influence of a specific property on As immobilization varies among different studies, and the development and application of arsenic passivation materials based on biochar often rely on empirical knowledge. To enhance immobilization efficiency and reduce labor and time costs, a machine learning (ML) model was employed to predict As immobilization efficiency before biochar application. In this study, we collected a dataset comprising 182 data points on As immobilization efficiency from 17 publications to construct three ML models. The results demonstrated that the random forest (RF) model outperformed gradient boost regression tree and support vector regression models in predictive performance. Relative importance analysis and partial dependence plots based on the RF model were conducted to identify the most crucial factors influencing As immobilization. These findings highlighted the significant roles of biochar application time and biochar pH in As immobilization efficiency in soils. Furthermore, the study revealed that Fe-modified biochar exhibited a substantial improvement in As immobilization. These insights can facilitate targeted biochar property design and optimization of biochar application conditions to enhance As immobilization efficiency.
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Arsénico , Carbón Orgánico , Aprendizaje Automático , Contaminantes del Suelo , Suelo , Carbón Orgánico/química , Arsénico/química , Contaminantes del Suelo/química , Contaminantes del Suelo/análisis , Suelo/química , Modelos QuímicosRESUMEN
With the increasing severity of arsenic (As) pollution, quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the precise control strategies. Taking the industrial-intensive Jinsha River Basin as typical area, a two-dimensional hydrodynamic water quality model coupled with Soil and Water Assessment Tool (SWAT) model was developed to accurately simulate the watershed-scale distribution and transport of As in the terrestrial and aquatic environment at high spatial and temporal resolution. The effects of hydro-climate change, hydropower station construction and non-point source emissions on As were quantified based on the coupled model. The result indicated that higher As concentration areas mainly centralized in urban districts and concentration slowly decreased from upstream to downstream. Due to the enhanced rainfall, the As concentration was significantly higher during the rainy season than the dry season. Hydro-climate change and the construction of hydropower station not only affected the dissolved As concentration, but also affected the adsorption and desorption of As in sediment. Furthermore, As concentration increased with the input of non-point source pollution, with the maximum increase about 30%, resulting that non-point sources contributed important pollutant impacts to waterways. The coupled model used in pollutant behavior analysis is general with high potential application to predict and mitigate water pollution.
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Arsénico , Monitoreo del Ambiente , Ríos , Contaminantes Químicos del Agua , Arsénico/análisis , China , Contaminantes Químicos del Agua/análisis , Ríos/química , Monitoreo del Ambiente/métodos , Modelos Químicos , Modelos TeóricosRESUMEN
Non-ferrous metal smelting poses significant risks to public health. Specifically, the copper smelting process releases arsenic, a semi-volatile metalloid, which poses an emerging exposure risk to both workers and nearby residents. To comprehensively understand the internal exposure risks of metal(loid)s from copper smelting, we explored eighteen metal(loid)s and arsenic metabolites in the urine of both occupational and non-occupational populations using inductively coupled plasma mass spectrometry with high-performance liquid chromatography and compared their health risks. Results showed that zinc and copper (485.38 and 14.00 µg/L), and arsenic, lead, cadmium, vanadium, tin and antimony (46.80, 6.82, 2.17, 0.40, 0.44 and 0.23 µg/L, respectively) in workers (n=179) were significantly higher compared to controls (n=168), while Zinc, tin and antimony (412.10, 0.51 and 0.15 µg/L, respectively) of residents were significantly higher than controls. Additionally, workers had a higher monomethyl arsenic percentage (MMA%), showing lower arsenic methylation capacity. Source appointment analysis identified arsenic, lead, cadmium, antimony, tin and thallium as co-exposure metal(loid)s from copper smelting, positively relating to the age of workers. The hazard index (HI) of workers exceeded 1.0, while residents and control were approximately at 1.0. Besides, all three populations had accumulated cancer risks exceeding 1.0 × 10-4, and arsenite (AsIII) was the main contributor to the variation of workers and residents. Furthermore, residents living closer to the smelting plant had higher health risks. This study reveals arsenic exposure metabolites and multiple metals as emerging contaminants for copper smelting exposure populations, providing valuable insights for pollution control in non-ferrous metal smelting.
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Metalurgia , Exposición Profesional , Humanos , Exposición Profesional/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Metales/orina , Metales/análisis , Medición de Riesgo , Arsénico/análisis , Monitoreo del Ambiente , Adulto , Contaminantes Ambientales/análisis , Persona de Mediana EdadRESUMEN
Cadmium (Cd) and arsenic (As) co-contamination has threatened rice production and food safety. It is challenging to mitigate Cd and As contamination in rice simultaneously due to their opposite geochemical behaviors. Mg-loaded biochar with outstanding adsorption capacity for As and Cd was used for the first time to remediate Cd/As contaminated paddy soils. In addition, the effect of zero-valent iron (ZVI) on grain As speciation accumulation in alkaline paddy soils was first investigated. The effect of rice straw biochar (SC), magnesium-loaded rice straw biochar (Mg/SC), and ZVI on concentrations of Cd and As speciation in soil porewater and their accumulation in rice tissues was investigated in a pot experiment. Addition of SC, Mg/SC and ZVI to soil reduced Cd concentrations in rice grain by 46.1%, 90.3% and 100%, and inorganic As (iAs) by 35.4%, 33.1% and 29.1%, respectively, and reduced Cd concentrations in porewater by 74.3%, 96.5% and 96.2%, respectively. Reductions of 51.6% and 87.7% in porewater iAs concentrations were observed with Mg/SC and ZVI amendments, but not with SC. Dimethylarsinic acid (DMA) concentrations in porewater and grain increased by a factor of 4.9 and 3.3, respectively, with ZVI amendment. The three amendments affected grain concentrations of iAs, DMA and Cd mainly by modulating their translocation within plant and the levels of As(III), silicon, dissolved organic carbon, iron or Cd in porewater. All three amendments (SC, Mg/SC and ZVI) have the potential to simultaneously mitigate Cd and iAs accumulation in rice grain, although the pathways are different.
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Arsénico , Cadmio , Carbón Orgánico , Magnesio , Oryza , Contaminantes del Suelo , Suelo , Oryza/química , Cadmio/análisis , Cadmio/química , Carbón Orgánico/química , Contaminantes del Suelo/análisis , Arsénico/análisis , Suelo/química , Magnesio/química , Hierro/química , Restauración y Remediación Ambiental/métodosRESUMEN
Growing evidences showed that heavy metals exposure may be associated with metabolic diseases. Nevertheless, the mechanism underlying arsenic (As) exposure and metabolic syndrome (MetS) risk has not been fully elucidated. So we aimed to prospectively investigate the role of serum uric acid (SUA) on the association between blood As exposure and incident MetS. A sample of 1045 older participants in a community in China was analyzed. We determined As at baseline and SUA concentration at follow-up in the Yiwu Elderly Cohort. MetS events were defined according to the criteria of the International Diabetes Federation (IDF). Generalized linear model with log-binominal regression model was applied to estimate the association of As with incident MetS. To investigate the role of SUA in the association between As and MetS, a mediation analysis was conducted. In the fully adjusted log-binominal model, per interquartile range increment of As, the risk of MetS increased 1.25-fold. Compared with the lowest quartile of As, the adjusted relative risk (RR) of MetS in the highest quartile was 1.42 (95% confidence interval, CI: 1.03, 2.00). Additionally, blood As was positively associated with SUA, while SUA had significant association with MetS risk. Further mediation analysis demonstrated that the association of As and MetS risk was mediated by SUA, with the proportion of 15.7%. Our study found higher As was remarkably associated with the elevated risk of MetS in the Chinese older adults population. Mediation analysis indicated that SUA might be a mediator in the association between As exposure and MetS.
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Arsénico , Exposición a Riesgos Ambientales , Síndrome Metabólico , Ácido Úrico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arsénico/sangre , Arsénico/toxicidad , China/epidemiología , Pueblos del Este de Asia , Exposición a Riesgos Ambientales/efectos adversos , Síndrome Metabólico/epidemiología , Síndrome Metabólico/inducido químicamente , Síndrome Metabólico/sangre , Ácido Úrico/sangreRESUMEN
Arsenic-related oxidative stress and resultant diseases have attracted global concern, while longitudinal studies are scarce. To assess the relationship between arsenic exposure and systemic oxidative damage, we performed two repeated measures among 5236 observations (4067 participants) in the Wuhan-Zhuhai cohort at the baseline and follow-up after 3 years. Urinary total arsenic, biomarkers of DNA oxidative damage (8-hydroxy-2'-deoxyguanosine (8-OHdG)), lipid peroxidation (8-isoprostaglandin F2alpha (8-isoPGF2α)), and protein oxidative damage (protein carbonyls (PCO)) were detected for all observations. Here we used linear mixed models to estimate the cross-sectional and longitudinal associations between arsenic exposure and oxidative damage. Exposure-response curves were constructed by utilizing the generalized additive mixed models with thin plate regressions. After adjusting for potential confounders, arsenic level was significantly and positively related to the levels of global oxidative damage and their annual increased rates in dose-response manners. In cross-sectional analyses, each 1% increase in arsenic level was associated with a 0.406% (95% confidence interval (CI): 0.379% to 0.433%), 0.360% (0.301% to 0.420%), and 0.079% (0.055% to 0.103%) increase in 8-isoPGF2α, 8-OHdG, and PCO, respectively. More importantly, arsenic was further found to be associated with increased annual change rates of 8-isoPGF2α (ß: 0.147; 95% CI: 0.130 to 0.164), 8-OHdG (0.155; 0.118 to 0.192), and PCO (0.050; 0.035 to 0.064) in the longitudinal analyses. Our study suggested that arsenic exposure was not only positively related with global oxidative damage to lipid, DNA, and protein in cross-sectional analyses, but also associated with annual increased rates of these biomarkers in dose-dependent manners.
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Arsénico , Exposición a Riesgos Ambientales , Estrés Oxidativo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , 8-Hidroxi-2'-Desoxicoguanosina , Arsénico/toxicidad , Biomarcadores/orina , China , Estudios Transversales , Daño del ADN , Pueblos del Este de Asia , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/toxicidad , Peroxidación de Lípido/efectos de los fármacos , Estudios Longitudinales , Estrés Oxidativo/efectos de los fármacosRESUMEN
Environmental pollution caused by arsenic or its compounds is called arsenic pollution. Arsenic pollution mainly comes from people's mining and smelting of arsenic compounds. In addition, the widespread use of arsenic compounds, such as the use and production of arsenic-containing pesticides, is also a source of arsenic contamination. Arsenic contamination leads to an increased risk of arsenic exposure, and the multi-organ toxicity induced by arsenic exposure is a global health problem. As a non-mammalian vertebrate with high nutrient levels, chickens readily absorb and accumulate arsenic from their food. Relevant studies have shown that arsenic exposure induces hepatotoxicity in chickens, and there has been a steady stream of research into the specific mechanisms involved. PANoptosis, a newly discovered and unique mode of programmed cell death (PCD) characterized by both apoptosis, cellular pyroptosis, and necroptosis. There are no studies to indicate whether chicken liver toxicity due to arsenic is associated with PANoptosis. Therefore, we established chicken animal models and chicken primary hepatocyte models exposed to different arsenic concentrations to dissect the role and mechanism of PANoptosis in arsenic exposure-induced hepatotoxicity in chickens. Our histopathological results showed that arsenic treatment caused dose-dependent damage to chicken liver structure. Meanwhile, different doses of arsenic treatment groups caused significant up-regulation of the protein level of ZBP1, a key factor of PANoptosis. And then consequently triggered the abnormal gene and protein expression levels of apoptosis-associated factors (Caspase-8, Caspase-7, Caspase-3), cellular pyroptosis-associated factors (NLRP3, ASC, GSDMD) and necroptosis-associated factors (RIPK1, RIPK3, MLKL). In conclusion, our study revealed that PANoptosis is involved in arsenic-induced chicken hepatotoxicity. Our findings provide a new perspective on the pathogenesis of arsenic exposure-induced hepatotoxicity in chickens.
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Arsénico , Pollos , Hígado , Animales , Arsénico/toxicidad , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Hepatocitos/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Necroptosis/efectos de los fármacos , Apoptosis/efectos de los fármacosRESUMEN
BACKGROUND: Oxidative stress mediated by reactive oxygen species (ROS) is a common denominator in arsenic toxicity. Arsenic stress in soil affects the water absorption, decrease stomatal conductance, reduction in osmotic, and leaf water potential, which restrict water uptake and osmotic stress in plants. Arsenic-induced osmotic stress triggers the overproduction of ROS, which causes a number of germination, physiological, biochemical, and antioxidant alterations. Antioxidants with potential to reduce ROS levels ameliorate the arsenic-induced lesions. Plant growth promoting rhizobacteria (PGPR) increase the total soluble sugars and proline, which scavenging OH radicals thereby prevent the oxidative damages cause by ROS. The main objective of this study was to evaluate the potential role of Arsenic resistant PGPR in growth of maize by mitigating arsenic stress. METHODOLOGY: Arsenic tolerant PGPR strain MD3 (Pseudochrobactrum asaccharolyticum) was used to dismiss the 'As' induced oxidative stress in maize grown at concentrations of 50 and 100 mg/kg. Previously isolated arsenic tolerant bacterial strain MD3 "Pseudochrobactrum asaccharolyticum was used for this experiment. Further, growth promoting potential of MD3 was done by germination and physio-biochemical analysis of maize seeds. Experimental units were arranged in Completely Randomized Design (CRD). A total of 6 sets of treatments viz., control, arsenic treated (50 & 100 mg/kg), bacterial inoculated (MD3), and arsenic stress plus bacterial inoculated with three replicates were used for Petri plates and pot experiments. After treating with this MD3 strain, seeds of corn were grown in pots filled with or without 50 mg/kg and 100 mg/kg sodium arsenate. RESULTS: The plants under arsenic stress (100 mg/kg) decreased the osmotic potential (0.8 MPa) as compared to control indicated the osmotic stress, which caused the reduction in growth, physiological parameters, proline accumulation, alteration in antioxidant enzymes (Superoxide dismutase-SOD, catalase-CAT, peroxidase-POD), increased MDA content, and H2O2 in maize plants. As-tolerant Pseudochrobactrum asaccharolyticum improved the plant growth by reducing the oxidation stress and antioxidant enzymes by proline accumulation. PCA analysis revealed that all six treatments scattered differently across the PC1 and PC2, having 85.51% and 9.72% data variance, respectively. This indicating the efficiency of As-tolerant strains. The heatmap supported the As-tolerant strains were positively correlated with growth parameters and physiological activities of the maize plants. CONCLUSION: This study concluded that Pseudochrobactrum asaccharolyticum reduced the 'As' toxicity in maize plant through the augmentation of the antioxidant defense system. Thus, MD3 (Pseudochrobactrum asaccharolyticum) strain can be considered as bio-fertilizer.
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Antioxidantes , Arsénico , Estrés Oxidativo , Agua , Zea mays , Zea mays/microbiología , Zea mays/efectos de los fármacos , Zea mays/crecimiento & desarrollo , Estrés Oxidativo/efectos de los fármacos , Arsénico/toxicidad , Antioxidantes/metabolismo , Agua/metabolismo , Burkholderiales/metabolismo , Burkholderiales/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Environmental Arsenic (As) exposure is one of the main health challenges in different area of the world. As is a significant factor responsible to the reproductive system toxicity in both male and female. In this study, the most important effects mechanisms and biomarkers related to environmental exposure to As and the reproductive system toxicity, and infertility risk are reviewed in male and female. The results showed that the most important As-induced reproductive system toxicity in the male were alteration in the quantity and quality of semen, testicular toxicity, oxidative stress, testosterone reduction, and sperm apoptosis. For female were oxidative stress, spontaneous miscarriage, reproductive cycle disruption, decrease in the estradiol, progesterone, and testosterone levels and impair fecundity. The main mechanisms of reproductive system toxicity caused by As exposure in male were, genotoxic effects, reduction of glutathione, disruption of sex hormones, sperm flagellum formation impairment, inhibition of spermatogenesis, disruption of cell signaling pathways, and metabolites disruption. For female were abnormal signaling in gene expression, hormonal homeostasis, As-accumulation in placental tissue and creation of reactive oxygen, disruption in the neurotransmitters balance, and sex hormones disruption. The suitable biomarkers for As-induced reproductive toxicity in male were changes in testosterone, one-carbon and lipid metabolism, noncoding RNAs, and steroid hormone homeostasis, and for female was human chorionic gonadotropin (hCG) changes. Finaly, taking selenium, zinc, silymarin, vitamins (C and E) and phytonutrients can be effective in reducing the As-induced reproductive system toxicity and infertility risk.
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Arsénico , Exposición a Riesgos Ambientales , Reproducción , Femenino , Masculino , Humanos , Arsénico/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Reproducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Contaminantes Ambientales/toxicidadRESUMEN
BACKGROUND: Arsenic, classified as a priority pollutant and human carcinogen by the IARC, is subject to stringent regulatory limits in food and water. Among various arsenic species found in water samples, arsenite (As(III)) is identified as the most toxic form. Given the limitations of conventional spectroscopic techniques in speciation analysis, there is a crucial need for innovative and sustainable methodologies that enable arsenic speciation. Simplifying these methodologies is essential for widespread applicability and effective environmental monitoring. RESULTS: This study proposes a simple and cost-effective analytical methodology for speciating inorganic arsenic in water samples. The method involves extracting As(III) into a polymer inclusion membrane (PIM) containing the extractant Cyanex 301 (bis(2,4,4-trimethylpentyl) dithiophosphinic acid), followed by analysis using energy dispersive X-ray fluorescence (EDXRF) spectrometry. The concentration of arsenate was measured after a reduction step using a thiosulfate/iodide mixture. This simple methodology allows a limit of quantification for trivalent arsenic (2 µg L-1), which is well below the World Health Organization's recommended maximum permissible level of As in drinking water (10 µg L-1). The method that is developed allows the determination of As at trace levels in waters with naturally occurring arsenic. SIGNIFICANCE AND NOVELTY: This study represents a significant advance in the field, providing a novel and efficient methodology for arsenic speciation analysis in water samples. By combining the advantages of polymer inclusion membrane (PIM) extraction with energy dispersive X-ray fluorescence (EDXRF) spectrometry, this study offers a cost-effective and environmentally friendly approach to address the critical issue of arsenic contamination in water sources, thereby contributing to enhanced environmental monitoring and public health protection.
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Arsénico , Polímeros , Espectrometría por Rayos X , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Polímeros/química , Arsénico/análisis , Espectrometría por Rayos X/métodos , Membranas ArtificialesRESUMEN
To better understand the impact of long-term irrigation practices on arsenic (As) accumulation in agricultural soils, 100 soil samples from depths of 0-20â¯cm were collected from the Datong basin, where the As-contaminated groundwater has been used for irrigation for several decades. Soil samples were analyzed for major elements, trace elements, and As, Fe speciation. Results reveal As content ranging from 4.00 to 14.5â¯mg/kg, an average of 10.2 ± 2.05â¯mg/kg, consistent with surveys conducted in 1998 and 2007. Arsenic speciation ranked in descending order as follows: As associated with silicate minerals (AsSi, 29.70 ± 7.53â¯%) > amorphous Fe-minerals associated As (AsFeox1, 26.40 ± 3.27â¯%) > crystalline Fe-minerals associated As (AsFeox2, 24.02 ± 4.60â¯%) > strongly adsorbed As (AsSorb, 14.29 ± 2.81â¯%) > As combined with carbonates and Fe-carbonates (AsCar, 2.30 ± 0.44â¯%) > weakly adsorbed As (AsDiss, 2.59 ± 1.00â¯%). The anomalous negative correlation between As and Fe content reflects the primary influence of soil provenance. Evidence from major element compositions and rare earth element patterns indicates that total As and Fe contents in soils are controlled by parent materials, exhibiting distinct north-south differences (As: higher levels in the north, lower levels in the south; Fe: higher levels in the south, lower levels in the north). Evidence from the Chemical Index of Alteration (CIA) and As/Ti ratio suggests that chemical weathering has led to As enrichment in the central basin. Notably, relationships such as AsDiss/Ti, AsSorb/Ti with CIA and total Fe content indicate significant influences of irrigation practices on adsorbed As (both weakly and strongly adsorbed) contents, showing a pattern of higher levels in the central basin and lower levels in the Piedmont. However, total As content remained stable after long-term irrigation, potentially due to the re-release of accumulated As via geochemical pathways during non-irrigated periods. These findings demonstrate that the soil systems can naturally remediate exogenous As contamination induced by irrigation practices. Quantitative assessment of the balance between As enrichment and re-release in soil systems is crucial for preventing soil As contamination, highlighting strategies like water-saving techniques and fallow periods to manage As contamination in agricultural areas using As-contaminated groundwater for irrigation.
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Riego Agrícola , Arsénico , Monitoreo del Ambiente , Agua Subterránea , Contaminantes del Suelo , Suelo , Riego Agrícola/métodos , Arsénico/análisis , Contaminantes del Suelo/análisis , Suelo/química , Agua Subterránea/química , Hierro/análisis , Hierro/química , Agricultura/métodos , Adsorción , Minerales/análisis , Minerales/químicaRESUMEN
Arsenic is a widespread carcinogen and an important etiological factor for lung cancer. Dysregulated miRNAs have been implicated in arsenic carcinogenesis and the mechanisms of arsenic-induced dysregulated miRNAs have not been fully elucidated. N6-methyladenosine (m6A) modification is known to modulate pri-miRNA processing. However, whether m6A-mediated pri-miRNA processing is involved in arsenic carcinogenesis is poorly understood. Here, we found that m6A modification was significantly increased in arsenite-transformed human bronchial epithelial BEAS-2B cells (0.5⯵M arsenite, 16 weeks). Meanwhile, METTL3 was significantly upregulated at week 12 and 16 during cell transformation. The proliferation, migration, invasion, and anchorage-independent growth of arsenite-transformed cells were inhibited by the reduction of m6A levels through METTL3 knockdown. Further experiments suggest that the oncogene miR-106b-5p is a potentially essential m6A target mediating arsenic-induced lung cancer. miR-106b-5p was observed to be upregulated after exposure to arsenite for 12 and 16 weeks, and the reduction of m6A levels caused by METTL3 knockdown inhibited miR-106b-5p maturation in arsenite-transformed cells. What's more, miR-106b-5p overexpression successfully rescued METTL3 knockdown-induced inhibition of the neoplastic phenotypes of transformed cells. Additionally, Basonuclin 2 (BNC2) was uncovered as a potential target of miR-106b-5p and downregulated by METTL3 via enhancing miR-106b-5p maturation. Additionally, the METTL3 inhibitor STM2457 suppressed neoplastic phenotypes of arsenite-transformed BEAS-2B cells by blocking pri-miR-106b methylation. These results demonstrate that m6A modification promotes the neoplastic phenotypes of arsenite-transformed BEAS-2B cells through METTL3/miR-106b-5p/BNC2 pathway, providing a new prospective for understanding arsenic carcinogenesis.
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Adenosina , Bronquios , Células Epiteliales , Metiltransferasas , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Adenosina/análogos & derivados , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Metiltransferasas/genética , Metiltransferasas/metabolismo , Bronquios/efectos de los fármacos , Bronquios/patología , Transformación Celular Neoplásica/inducido químicamente , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/efectos de los fármacos , Arsénico/toxicidad , Arsenitos/toxicidad , Proliferación Celular/efectos de los fármacos , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Línea Celular , FenotipoRESUMEN
Non-invasive proxies, such as fur and feathers, are likely to be increasingly used to assess the potential exposure of chemicals, including trace metals and metalloids. However, the amount of external contamination is usually unknown, and there is no standard method for removing external contamination of trace metals in fur or feathers. To date, 40â¯% of studies published related to the measurement of trace metal levels in fur or the hair of non-human mammals and 24â¯% of studies in feathers do not state any washing methods or did not wash the samples before analysis. We assessed three washing techniques to remove external contamination of arsenic (As), lead (Pb), and zinc (Zn) from bat fur. We selected the three most frequently used fur washing methods from literature. To test these methods, fur samples from great flying foxes (Pteropus neohibernicus neohibernicus, n=15 individuals) from Papua New Guinea preserved over eight decades (AMNH, USA) were used. Percentages of trace metal removed are 87.19â¯% (SD= 12.28), 92.99â¯% (SD= 5.5) and 88.57â¯% (SD= 9.33) for As, 54.72â¯% (SD= 31.64), 55.89â¯% (SD= 37.87), and 53.93â¯% (SD= 41.28) for Pb, and 74.03â¯% (SD= 22.96), 22.93â¯% (SD= 73), and 24.95â¯% (SD= 49.5) for Zn using M2, M3, and M4, respectively. We also assessed four washing techniques to remove external contamination of arsenic (As), mercury (Hg), and zinc (Zn) from bird feathers. We identified the four most prevalent washing techniques in the literature used for feathers. We used feathers from the great horned owl (Bubo virginianus) and the great blue heron (Ardea herodias) to test these methods. Percentages of trace metal removed are 34.35â¯% (SD= 44.22), 69.22â¯% (SD= 36.5), 62.59â¯% (SD= 48.37), and 80.89â¯% (SD= 14.54) for As, 66.97â¯% (SD= 13.26), 29.4â¯% (SD= 67.06), 49.68â¯% (SD= 42.33), and 28.88â¯% (SD= 69) for Hg, and <0â¯% (SD= 80.1), 0â¯% (SD= 29.55), 11.23â¯% (SD= 47.73), and 57.09â¯% (SD= 21.2) for Zn using M2, M3, M4, and M5, respectively. This study shows the importance of washing fur and feather samples prior to trace metals analyses in ecotoxicology and biomonitoring studies.
Asunto(s)
Pelaje de Animal , Arsénico , Quirópteros , Monitoreo del Ambiente , Plumas , Plomo , Oligoelementos , Zinc , Animales , Plumas/química , Oligoelementos/análisis , Monitoreo del Ambiente/métodos , Pelaje de Animal/química , Plomo/análisis , Arsénico/análisis , Zinc/análisis , Contaminantes Ambientales/análisis , Aves , Cabello/químicaRESUMEN
The primary purpose of present study was to explore the effects of arsenic exposure on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/nuclear transcription factor-κB (NF-κB) signaling pathway in the hippocampus of offspring mice at different developmental stages. Sodium arsenite (NaAsO2) at doses of 0, 15, 30 or 60â¯mg/L administered to female mice and their pups. The nuclear translocation levels of NF-κB were assessed by EMSA. Real-time RT-PCR was used to measure Akt, NF-κB and PI3K mRNA levels. Protein expressions of PI3K, p-Akt, inhibitor kappa B kinase (IKK), p-NF-κB, protein kinase A (PKA), inhibitor kappa B (IκB), and cAMP response element-binding protein (CREB) were measured by Western blot. Results disclosed that exposure to 60â¯mg/L NaAsO2 could suppress NF-κB levels of nuclear translocation of postnatal day (PND) 20 and PND 40 mice. Arsenic downregulated the transcriptional and translational levels of PI3K, Akt and NF-κB. Additionally, protein expressions of p-IKK, p-IκB, PKA and p-CREB also reduced. Taken together, results of present study indicated that arsenic could downregulate the PI3K/Akt/NF-κB signaling pathway, particularly on PND 40, which might be involved in the cognitive impairments.
Asunto(s)
Arsénico , Hipocampo , FN-kappa B , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Animales , Femenino , Transducción de Señal/efectos de los fármacos , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Ratones , Arsénico/toxicidad , Fosfatidilinositol 3-Quinasas/metabolismo , Arsenitos/toxicidad , Compuestos de Sodio/toxicidad , Embarazo , Masculino , Efectos Tardíos de la Exposición Prenatal/inducido químicamenteRESUMEN
The association between metal mixtures and kidney function has been reported. However, reports on the mechanism of metal toxicity were limited. Oxidative stress was reported as a possible cause. This study aimed to determine the association between of kidney function and metals, such as arsenic (As), cadmium (Cd), cobalt (Co), copper (Cu), lead (Pb), selenium (Se), and zinc (Zn), and to explore the possible mediating role of tumor necrosis factor alpha (TNF-α) between metal toxicity and kidney function. In this study, we recruited 421 adults from a health examination. The concentration of blood metals was analyzed using inductively coupled plasma mass spectrometry. We used linear regression models to assess the association between metals and TNF-α. Then, mediation analysis was applied to investigate the relationship between metal exposure, TNF-α, and kidney function. In univariate linear regression, blood As, Cd, Co, Cu, Pb, and Zn levels significantly increased TNF-α and decreased kidney function. Higher blood As and Pb levels significantly increased TNF-α in multivariable linear regressions after adjusting for covariates. We found that blood levels of As (coefficients = -0.021, p = 0.011), Pb (coefficients = -0.060, p < 0.001), and Zn (coefficients = -0.230, p < 0.001) showed a significant negative association with eGFR in the multiple-metal model. Furthermore, mediation analysis showed that TNF-α mediated 41.7â¯%, 38.8â¯%, and 20.8â¯% of blood Cd, As and Pb, respectively. Among the essential elements, TNF-α mediated 24.5â¯%, 21.5â¯% and 19.9â¯% in the effects of blood Co, Cu, and Zn on kidney function, respectively. TNF-α, acting as a mediator, accounted for 20.1â¯% of the contribution between the WQS score of metal mixtures and the eGFR (pâ¯<â¯0.001). This study suggested that TNF-α may be a persuasive pathway mediating the association between metals and kidney function. Inflammation and kidney injury could be the underlying mechanisms of metal exposure. However, there is still a need to clarify the biochemical mechanism in follow-up studies.
Asunto(s)
Riñón , Análisis de Mediación , Metales Pesados , Factor de Necrosis Tumoral alfa , Factor de Necrosis Tumoral alfa/sangre , Humanos , Masculino , Femenino , Riñón/efectos de los fármacos , Persona de Mediana Edad , Metales Pesados/sangre , Metales Pesados/toxicidad , Adulto , Contaminantes Ambientales/sangre , Contaminantes Ambientales/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Modelos Lineales , Arsénico/sangre , Arsénico/toxicidad , Metales/sangre , Metales/toxicidadRESUMEN
Arsenic, a neurotoxic metalloid, poses significant health risks. However, ellagic acid, renowned for its antioxidant properties, has shown potential in neuroprotection. This study aimed to investigate the neuroprotective effects of ellagic acid against arsenic-induced neuronal ferroptosis and cognitive impairment and elucidate the underlying mechanisms. Using an arsenic-exposed Wistar rat model and an arsenic-induced HT22 cells model, we assessed cognitive ability, measured serum and brain arsenic levels, and evaluated pathological damage through histological analysis and transmission electron microscopy. Additionally, we examined oxidative stress and iron ion levels using GSH, MDA, ROS and tissue iron biochemical kits, and analyzed the expression of ferroptosis-related markers using western blot and qRT-PCR. Our results revealed that arsenic exposure increased both serum and brain arsenic levels, resulting in hippocampal pathological damage and subsequent decline in learning and memory abilities. Arsenic-induced neuronal ferroptosis was mediated by the inhibition of the xCT/GSH/GPX4/Nrf2 signaling axis and disruption of iron metabolism. Notably, ellagic acid intervention effectively reduced serum and brain arsenic levels, ameliorated neuronal damage, and improved oxidative stress, ferroptosis, and cognitive impairment. These beneficial effects were associated with the activation of the Nrf2/Keap1 signaling pathway, upregulation of GPX4 expression, and enhanced iron ion excretion. In conclusion, ellagic acid demonstrates promising neuroprotective effects against arsenic-induced neurotoxicity by mitigating neuronal ferroptosis and cognitive impairment.
Asunto(s)
Arsénico , Disfunción Cognitiva , Ácido Elágico , Ferroptosis , Factor 2 Relacionado con NF-E2 , Neuronas , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Ratas Wistar , Transducción de Señal , Animales , Ácido Elágico/farmacología , Ferroptosis/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/tratamiento farmacológico , Arsénico/toxicidad , Transducción de Señal/efectos de los fármacos , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Ratas , Masculino , Neuronas/efectos de los fármacos , Neuronas/patología , Estrés Oxidativo/efectos de los fármacos , Fármacos Neuroprotectores/farmacologíaRESUMEN
Fifteen poplar varieties were used in a field trial to investigate the phytoremediation efficiency, stress resistance, and wood property of poplar hybrid varieties with diverse genetic backgrounds under the composite pollution of heavy metals. The coefficient of variation and clone repeatability for growth traits and Cd concentration were large. The Cd accumulation of poplar varieties 107 and QHQ reached 1.9 and 1.7â¯mg, respectively, followed by QHB, Ti, 69, and Pa, in which Cd accumulation reached 1.3â¯mg. Most of the intra-specific hybrid varieties (69, QH1, SL4, T3, and ZL46) had low Cd concentrations and small biomass, resulting in weak Cd accumulation and low phytoremediation efficiency for Cd-polluted soil. By contrast, the inter-sectional and inter-specific hybrid varieties exhibited better growth performance and accumulated higher concentrations of heavy metals than the intra-specific hybrids. The bioconcentration factor and translocation factor of Hg, As, and Pb were less than 1, indicating that poplars have low phytoremediation efficiency for these heavy metals. The hybrids between section Aigeiros and Tacamahaca (QHQ and QHB) and the inter-specific hybrid 107 within section Aigeiros were more resistant to composite heavy metal stress than the other poplar varieties were partially because of their high levels of free proline that exceeded 93⯵g·g-1 FW. According to the correlation analysis of the concentrations of the different heavy metals, the poplar roots absorbed different heavy metals in a cooperative manner, indicating that elite poplar varieties with superior capacity for accumulating diverse heavy metals can be bred feasibly. Compared with the intra-specific hybrid varieties, the inter-sectional (QHQ and QHB) and inter-specific (107) hybrid varieties had higher pollution remediation efficiency, larger biomass, higher cellulose content, and lower lignin content, which is beneficial for pulpwood. Therefore, breeding and extending inter-sectional (QHQ and QHB) and inter-specific hybrid varieties can improve the phytoremediation of composite pollution.