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High temperatures and providing sufficient time for the thermal desorption of persistent organic pollutants (POPs) from contaminated clay soils can lead to intensive energy consumption. Therefore, this article provides a critical review of the potential additives which can improve soil texture and increase the volatility of POPs, and then discusses their enhanced mechanisms for contributing to a green economy. Ca-based additives have been used to reduce plasticity of bentonite clay, absorb water and replenish system heat. In contrast, non-Ca-based additives have been used to decrease the plasticity of kaolin clay. The soil structure and soil plasticity can be changed through cation exchange and flocculation processes. The transition metal oxides and alkali metal oxides can be applied to catalyze and oxidize polycyclic aromatic hydrocarbons, petroleum and emerging contaminants. In this system, reactive oxygen species (â¢O2- and â¢OH) are generated from thermal excitation without strong chemical oxidants. Moreover, multiple active ingredients in recycled solid wastes can be controlled to reduce soil plasticity and enhance thermal catalysis. Alternatively, the alkali, nano zero-valent iron and nano-TiN can catalyze hydrodechlorination of POPs under reductive conditions. Especially, photo and photo-thermal catalysis are discussed to accelerate replacement of fossil fuels by renewable energy in thermal remediation.
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Arcilla , Restauración y Remediación Ambiental , Contaminantes del Suelo , Suelo , Arcilla/química , Suelo/química , Catálisis , Contaminantes del Suelo/química , Restauración y Remediación Ambiental/métodos , CalorRESUMEN
Persulfate advanced oxidation technology is widely utilized for remediating organic-contaminated groundwater. Post-remediation by persulfate oxidation, the aromaticity of dissolved organic matter (DOM) in groundwater is significantly reduced. Nevertheless, the evolution trends of aromaticity and related structural changes in DOM remained unclear. Here, we selected eight types of DOM to analyze the variation in aromaticity, molecular weight, and fluorescence characteristics during oxidation by persulfate using optical spectroscopy and parallel faction analysis combined with two-dimensional correlation spectroscopy analysis (2D PARAFAC COS). The results showed diverse trends in the changes of aromaticity and maximum fluorescence intensity (Fmax) among different types of DOM as the reaction time increases. Four types of DOM (humic acid 1S104H, fulvic acid, and natural organic matters) exhibited an initially noteworthy increase in aromaticity followed by a decrease, while others demonstrated a continuous decreasing trend (14.3%-69.4%). The overall decreasing magnitude of DOM aromaticity follows the order of natural organic matters ≈ commercial humic acid > fulvic acid > extracted humic acid. The Fmax of humic acid increased, exception of commercial humic acid. The Fmax of fulvic acid initially decreased and then increased, while that of natural organic matters exhibited a decreasing trend (86.4%). The fulvic acid-like substance is the main controlling factor for the aromaticity and molecular weight of DOM during persulfate oxidation process. The oxidation sequence of fluorophores in DOM is as follows: fulvic-like substance, microbial-derived humic-like substance, humic-like substance, and aquatic humic-like substance. The fulvic-like and microbial-derived humic-like substances at longer excitation wavelengths were more sensitive to the response of persulfate oxidation than that of shorter excitation wavelengths. This result reveals the structure evolution of DOM during persulfate oxidation process and provides further support for predicting its environmental behavior.
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Immune checkpoints are essential regulators of immune responses, either by activating or suppressing them. Consequently, they are regarded as pivotal elements in the management of infections, cancer, and autoimmune disorders. In recent years, researchers have identified numerous soluble immune checkpoints that are produced through various mechanisms and demonstrated biological activity. These soluble immune checkpoints can be produced and distributed in the bloodstream and various tissues, with their roles in immune response dysregulation and autoimmunity extensively documented. This review aims to provide a thorough overview of the generation of various soluble immune checkpoints, such as sPD-1, sCTLA-4, sTim-3, s4-1BB, sBTLA, sLAG-3, sCD200, and the B7 family, and their importance as indicators for the diagnosis and prediction of autoimmune conditions. Furthermore, the review will investigate the potential pathological mechanisms of soluble immune checkpoints in autoimmune diseases, emphasizing their association with autoimmune diseases development, prognosis, and treatment.
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Enfermedades Autoinmunes , Proteínas de Punto de Control Inmunitario , Humanos , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/diagnóstico , Proteínas de Punto de Control Inmunitario/metabolismo , Proteínas de Punto de Control Inmunitario/genética , Biomarcadores , Animales , Autoinmunidad , Pronóstico , Susceptibilidad a Enfermedades/inmunologíaRESUMEN
Health risks of microplastic exposure have drawn growing global concerns due to the widespread distribution of microplastics in the environment. However, more evidence is needed to understand the exposure characteristics of microplastics owing to the limitation of current spectrum technologies, especially the missing information on small-sized particles. In the present study, laser direct infrared spectroscopy and thermal desorption-gas chromatography-mass spectrometry combined pyrolysis using a tubular furnace (TD-GC/MS) were employed to comprehensively detect the presence of plastic particles down to 0.22 µm in human excreted samples. The results showed that polyethylene (PE), polyvinyl chloride, PE terephthalate (PET), and polypropylene dominated large-sized (>20 µm) and small-sized plastic plastics (0.22-20 µm) in feces and urine. Moreover, fragments accounted for 60.71 and 60.37% in feces and urine, respectively, representing the most pervasive shape in excretion. Surprisingly, the concentration of small-sized particles was significantly higher than that of large-sized microplastics, accounting for 56.54 and 50.07% in feces (345.58 µg/g) and urine (6.49 µg/mL). Significant positive correlations were observed between the level of plastic particles in feces and the use of plastic containers and the consumption of aquatic products (Spearman correlation analysis, p < 0.01), suggesting the potential sources for plastic particles in humans. Furthermore, it is estimated that feces was the primary excretory pathway, consisting of 94.0% of total excreted microplastics daily. This study provides novel evidence regarding small-sized plastic particles, which are predominant fractions in human excretion, increasing the knowledge of the potential hazards of omnipresent microplastics to human exposure.
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Heces , Microplásticos , Plásticos , Humanos , Heces/química , Tamaño de la Partícula , Cromatografía de Gases y Espectrometría de Masas , Monitoreo del AmbienteRESUMEN
Per- and polyfluoroalkyl substances (PFASs) have been widely detected in various food, which has attracted worldwide concern. However, the factors influencing the transfer and bio-accumulation of PFASs from soils to wheat in normal farmland, is still ambiguous. We investigated the PFASs accumulation in agricultural soils and grains from 10 cites, China, and evaluated the health risks of PFASs via wheat consumption. Our results show that ∑PFASs in soils range from 0.34 µg/kg to 1.59 µg/kg with PFOA and PFOS dominating, whilst ∑PFASs in wheats range from 2.74 to 6.01 µg/kg with PFOA, PFBA and PFHxS dominating. The lower pH conditions and high total organic carbon (TOC) could result in the higher accumulation of PFASs in soils and subsequently in wheat grains, whilst the bioaccumulation factors of PFASs increase with increasing pH conditions but not with TOC. The estimated daily intake (EDI) values of PFBA, PFOA, and PFHxS are relatively high, but data supports that ingesting wheat grains does not result in any potential risk to the human beings. Our studies provided more information about PFASs accumulation in wheat grains, and help us understand the current potential risks of PFASs in food.
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Fluorocarburos , Contaminantes del Suelo , Triticum , Triticum/metabolismo , Triticum/química , Fluorocarburos/análisis , Fluorocarburos/metabolismo , Medición de Riesgo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , China , Humanos , Bioacumulación , Suelo/química , Contaminación de Alimentos/análisis , Grano Comestible/química , Monitoreo del AmbienteRESUMEN
The accumulation of contaminants like PAHs in soil due to industrialization, urbanization, and intensified agriculture poses environmental challenges, owing to their persistence, hydrophobic nature, and toxicity. Thus, the degradation of PAHs has attracted worldwide attention in soil remediation. This study explored the effect of noble metal and temperature on the degradation of various polycyclic aromatic hydrocarbons (PAHs) in soil, as well as the types of reactive radicals generated and mechanism. The Fe-Pd/AC and Fe-Pt/AC activated persulfate exhibited high removal efficiency of 19 kinds of PAHs, about 79.95 % and 83.36 %, respectively. Fe-Pt/AC-activated persulfate exhibits superior degradation efficiency than that on Fe-Pd/AC-activated persulfate, due to the higher specific surface area and dispersity of Pt particles, thereby resulting in increased reactive radicals (·OH, SO4-· and ·OOH). Additionally, thermal activation enhances the degradation of PAHs, with initial efficiencies of 64.20 % and 55.49 % on Fe-Pd/AC- and Fe-Pt/AC-activated persulfate systems respectively, increasing to 76.05 % and 73.14 % with elevated temperatures from 21.5 to 50 °C. Metal and thermal activation facilitate S2O82- activation, generating reactive radicals, crucial for the degradation of PAHs via ring opening and oxygen hydrogenation reactions, yielding low-ring oxygen-containing derivatives such as organic acids, keto compounds, ethers, and esters. Furthermore, understanding the impact of parameters such as activation temperature and the types of noble metals on the degradation of PAHs within the activated persulfate system provides a theoretical foundation for the remediation of PAH-contaminated soil.
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Many gastrointestinal simulation methods have been used to predict bioavailability, but the suitability of different methods for the same metal(loid)s varies widely, which inevitably affects the accuracy of human health risk assessment. Arsenic is a common and important contaminant in many contaminated land situations. It can be readily absorbed and has teratogenic and mutagenic toxicity. Therefore, in this study, four the most commonly used in vitro simulation methods (the Physiologically Based Extraction Test (PBET), In Vitro Gastrointestinal Method (IVG), Soluble Bioavailability Research Consortium (SBRC), the Unified BARGE Method (UBM)) were tested against an in vivo animal live model, to evaluate their effectiveness for the prediction of soil As bioavailability in 10 industrially contaminated soils. The soil As relative bioavailability (RBA) varied between 15% and 68% in the different soils. As bioaccessibility differed between the 4 gastro-intestinal simulation methods. Gastric phase of UBM (UBMG) predicted As relative bioavailability the best of the 4 assays (R2 = 0.81). This study provides theoretical and technical support to refine human health risk assessment of As in soils from urban industrial legacy contaminated sites.
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Arsénico , Contaminantes del Suelo , Animales , Humanos , Arsénico/análisis , Suelo , Disponibilidad Biológica , Contaminantes del Suelo/análisis , Contaminación AmbientalRESUMEN
The attitude of the Chinese government towards social organizations (SOs) is crucial, as it affects the management rule and development tendency of SOs. To research the rule of SOs' participation in social governance in China, this study used a new historical perspective, the institutional development perspective, to conduct its exploration. This perspective provides an accurate measure of the reality of the SOs' participation, as it involves a mixed research methodology using continuous data from 73 years of reports and content mining, as well as topic clustering analysis to reveal a macroscopic and multi-line picture. Using a co-word analysis of hundreds of reports, from 1949-2021, in the People's Daily, an official newspaper of the Communist Party of China, this study quantified changes in intensity, emotion, and content regarding social organization participation in social governance through topic distribution. Three trends were revealed: (1) "social-oriented character" and "organized-oriented character" were identified during the change in SOs; (2) the extent of being managed gradually strengthened and shifted from the Communist Youth League of China to the Community Party of China; (3) the goals of SOs shifted from general to innovated function in special charitable organizations. The institutional development perspective can complement the focus event perspective, including a new method, co-word analysis, to examine official Chinese media and validate the Administrative Absorption of Society (AAS) theory by identifying two lines of topic clustering trends. The attention distribution analysis in official media from an institutional development perspective can help explore the role of official media reports in analyzing the allocation of national attention and provide new analytical methods for big data mining to establish the social and organizational natures of SOs to optimize their roles. It offers a basis for modern social governance policy innovation in China.
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Gobierno , Política Pública , Humanos , Adolescente , China , Organizaciones , ComunismoRESUMEN
The demand for energy continues to increase as the global economy continues to grow. The role of oilfield chemicals in the process of oil and gas exploration, development, and production is becoming more and more important, and the demand is rising year by year. The support of national policies and the formulation of environmental protection regulations have put forward higher requirements for oilfield chemical products, which has promoted the innovative research and development and market application of oilfield chemicals. Polyformaldehyde glycol ether polymer (PGEP) is simple to synthesize, easily biodegradable, green and environmentally friendly, and in line with the development trend of chemicals used in oil and gas development. The interfacial tension performance of PGEP after compounding with different surfactants can reach as low as 0.00034 mN/m, which meets the requirements of the oilfield (interfacial tension ≤ 5 × 10-3 mN/m). The best oil washing efficiency performance of PGEP compounded with different surfactants reached 78.2%, which meets the requirements of the oilfield (oil washing efficiency ≥ 40%). The fracturing fluid drainage efficiency of PGEP after compounding with different surfactants reaches 22%, which meets the requirements of the oilfield (drainage efficiency ≥ 15%). The surface interfacial tension of the system remains constant after the concentration exceeds 0.2% and decreases with lower concentrations. The drainage efficiency increases with increasing concentrations in the range below 0.6%. It was determined that PGEP can be used as a surfactant instead of fatty-alcohol ethoxylates (FAE) in oilfield development.
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Arsenic is a metalloid with carcinogenic properties and has been classified as a Category I carcinogen by the International Agency for Research on Cancer (IARC). Freeze-thaw processes affect the migration and transformation of soil heavy metals, as well as adsorption/desorption and redox reactions. However, there is limited research directly addressing the impact of freeze-thaw processes on the bioavailability of soil heavy metals. In this study, we focused on As and selected As-contaminated soil samples from three types of legacy sites in heavy industrial areas. Under controlled freeze-thaw experimental conditions, we utilized both in vivo and in vitro bioavailability measurement methods to investigate whether and how freeze-thaw processes affect the bioavailability of soil As. The results of this study showed that freeze-thaw processes reduced soil pH (P < 0.05), CEC, SOM, and particle size, with decreases of 0.33, 1.2 cmol/kg, 5.2 g/kg, and 54 µm, respectively. It also increased weight specific surface area (BET) (P < 0.05), with an increase of 300 m2/kg. Freeze-thaw processes increased the proportions of exchangeable (P < 0.05), carbonate-bound, and iron-manganese oxide-bound As (P < 0.05), but reduced the proportions of organic-bound and residual As (P < 0.05). Freeze-thaw processes significantly increased the relative bioavailability and bioaccessibility of As, with increases of 32 ± 9.6% and 13 ± 0.23%, respectively. Soil pH, SOM, BET and electronic conductivity (EC) were identified as factors which could contribute to the increased bioavailability of As due to freeze-thaw processes. These results provide new insights and evidence for refining the assessment of human health risks associated with heavy metal contamination in polluted soils.
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Arsénico , Metales Pesados , Contaminantes del Suelo , Humanos , Suelo/química , Disponibilidad Biológica , Metales Pesados/análisis , Hierro/análisis , Contaminantes del Suelo/análisisRESUMEN
The hydroxyl radicals (OH) produced from Fe(II) oxidation upon reoxidation of reduced Fe-bearing clay minerals (RFC) have received increased attention and thermal activation was used to enhance Fe(II) oxidation to improve OH production. However, changes in mineral morphology and structure during thermally-activated RFC reoxidation are not yet clear. Herein, the Fe(II) oxidation extent was measured by chemical analysis during the reoxidation of model RFC (reduced nontronite (rNAu-2) at elevated temperatures. Mineralogical variation of rNAu-2 particles was observed by scanning electron microscopy (SEM), Mössbauer spectra, and X-ray photoelectron spectroscopy (XPS). The structural Fe(II) oxidation in rNAu-2 was accelerated with increasing temperature, accompanied by the transformation of structural entities and the dissolution of Fe and Si, while the overall structure of rNAu-2 minerals was relatively intact. The surface microstructure of particles showed the dissolved holes, net-shape flocs, and even large pore channels after Fe(II) oxidation by thermal activation. Moreover, the rearrangement of structural Fe(II) entities, the regeneration of edge Fe(II), and the electron transport from the interior to the edge were enhanced during rNAu-2 reoxidation by thermal activation. The increasing electron transfer at elevated temperatures could possibly be owing to the increasing number of reactive sites by increasing the internal disorder of rNAu-2. This work provides novel insights into the structural and mineralogical changes in promoting electron transfer upon RFC reoxidation.
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Thermally-enhanced soil vapor extraction (T-SVE) remediation technology is widely used in organic-contaminated sites due to its high efficiency, short remediation period and controllable secondary contamination. However, the remediation efficiency is affected by the complex site factors, which leads to the uncertainty of the remediation process and energy waste. Thus, it is necessary to optimize T-SVE systems to accurately remediate the sites. In this work, a pilot site of reagent factory in Tianjin was taken as the research object to validate the model, and the T-SVE process parameters of a VOCs-contaminated sites were predicted by this simulation method. The simulation results showed that the Nash efficiency coefficient E of the measured and simulated temperature rise data in the study area was 0.885, and the linear correlation coefficient R of the measured and simulated concentrations of cis-1,2-dichloroethylene after remediation was 0.877, indicating that this simulation method is highly reliable. Based on this numerical simulation method, some parameters of the T-SVE process at the VOCs-contaminated site of an insulation plant in Harbin were simulated and optimized. Included a heating well spacing of 3.0 m, extraction pressure of 40 Kpa, extraction well influence radius of 4.35 m, extraction flow rate of 2.97 × 10-4 m3/s, and a theoretical number of 25 extraction wells (adjusted to 29 wells in practice), and the corresponding extraction well layout has been designed. The results can provide a technical reference for the future application of T-SVE in the remediation of organic-contaminated sites.
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Restauración y Remediación Ambiental , Contaminantes del Suelo , Suelo , Simulación por Computador , GasesRESUMEN
Iron in biochar composite loaded with Fe (Fex@biochar) is crucial for persulfate activation. However, the iron dosages-driven mechanism linked to the speciation, electrochemical property, and persulfate activation with Fex@biochar remains ambiguous. We synthesized and characterized a series of Fex@biochar and evaluated its catalytic performance in 2,4-dinitrotoluene removal experiments. With increasing FeCl3 dosage, iron speciation in Fex@biochar changed from γ-Fe2O3 to Fe3O4, and the variation in functional groups was as follows: Fe-O, aliphatic C-O-H, O-H, aliphatic C-H, aromatic CC or CO, and C-N. The electron accepting capacity of Fex@biochar increased as the FeCl3 dosage increased from 10 to 100 mM but decreased at 300 and 500 mM FeCl3. 2,4-dinitrotoluene removal first increased and subsequently decreased, reaching 100% in the persulfate/Fe100@biochar system. The Fe100@biochar also showed good stability and reusability for PS activation, verified by five test cycles. The mechanism analysis indicated that the iron dosage altered the Fe (⠢) content and electron accepting capacity of Fex@biochar during pyrolysis, further controlling persulfate activation and 2,4-dinitrotoluene removal. These results support the preparation of eco-friendly Fex@biochar catalysts.
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Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/química , Hierro/química , Carbón Orgánico/químicaRESUMEN
Benzo[a]pyrene (BaP) is a highly carcinogenic pollutant of global concern. There is a need for a comprehensive assessment of regulation decisions for BaP-contaminated site management. Herein, we present a quantitative evaluation of remediation decisions from 206 contaminated sites throughout China between 2011 and 2021 using the cumulative distribution function (CDF) and related statistical methodologies. Generally, remediation decisions seek to establish remediation goals (RGs) based on the risk control values (RCVs). Cumulative frequency distributions, followed non-normal S-curve, emerged multiple nonrandom clusters. These clusters are consistent with regulatory guidance values (RGVs), of national and local soil levels in China. Additionally, priority interventions for contaminated sites were determined by prioritizing RCVs and identifying differences across industrial sectors. Notably, we found that RCVs and RGs became more relaxed over time, effectively reducing conservation and unsustainable social and economic impacts. The joint probability curve was applied to model decision values, which afforded a generic empirically important RG of 0.57 mg/kg. Overall, these findings will help decision-makers and governments develop appropriate remediation strategies for BaP as a ubiquitous priority pollutant.
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Contaminantes Ambientales , Restauración y Remediación Ambiental , Contaminantes del Suelo , Benzo(a)pireno/análisis , Objetivos , ChinaRESUMEN
Persulfate/Fe2+-based advanced oxidation processes are widely used to treat water contaminated with 2,4-dinitrotoluene (DNT). However, the oxidation of DNT by persulfate/Fe2+ in the presence of the chloride ion (Clâ») has not been addressed, and the transformation pathways and toxicities of the intermediate products remain unclear. In this study, the effect of different Clâ» concentrations on the oxidation of DNT was investigated by persulfate/Fe2+. After the addition of 1.0 mM Clâ» and 6 h of oxidation, the removal efficiency of DNT increased by 68.5%. Scavenging experiments and an electron spin resonance analysis suggested that Clâ» caused hydroxyl radicals to increase in content in the persulfate/Fe2+ system, thus promoting the removal of DNT. Eight intermediate products of DNT were accurately detected using high-resolution mass spectrometry, and the transformation pathways of DNT were proposed, including hydroxylation/oxidation, elimination of the nitro group, and chlorination process. The acute and chronic toxicities of the intermediate products decreased during the oxidation process, but chlorinated by-products posed a higher toxicological risk. This result is vital for the practical application and environmental safety evaluation of persulfate/Fe2+-based advanced oxidation.
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Cloruros , Contaminantes Químicos del Agua , Oxidación-Reducción , Dinitrobencenos/toxicidad , Halógenos , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/química , Sulfatos/químicaRESUMEN
In-situ thermal desorption (ISTD) has attracted increasing attention owing to the efficient removal of organic contaminants from contaminated sites. However, it is poorly understood that whether and to what extent contamination degradation occurs upon oxygenation of reduced Fe-bearing clay minerals (RFC) in the subsurface during ISTD. In this study, we evaluated the mechanism of contaminant degradation upon oxygenation of reduced clay minerals during the ISTD. Reduced nontronite (rNAu-2) and montmorillonite (rSWy-3) were selected as RFC models. Results showed that thermal treatment during ISTD could significantly enhance phenol degradation, which increased from 25.8 % at 10 °C to 74.4 % at 70 °C in rNAu-2 and from 17.7 % at 10 °C to 49.8 % at 70 °C in rSWy-3. Correspondingly, the cumulative â¢OH at steady-state ([â¢OH]ss) increased by 3.7 and 1.5 times, respectively. The acceleration of Fe(II) oxidation with increasing temperature could be mainly responsible for [â¢OH]ss generation, which degrades phenol. Moreover, thermal treatment improved the fast oxidation of trioctahedral entities Fe(II)Fe(II)Fe(II) (TOF) and the slow oxidation of dioctahedral entities Fe(II)Fe(II) (DTF1), AlFe(II) (DAF1), and Fe(II)Fe(III) (DTF2). Our study suggests that the overlooked degradation progress of phenol by oxygenation of RFC during ISTD, and it could be favorable for contaminant degradation during remediation.
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Radical Hidroxilo , Fenol , Arcilla , Compuestos Férricos , Fenoles , MineralesRESUMEN
As global warming intensifies, there will be increased uncertainty as to the environmental behavior and risks from heavy metals in industrial/legacy contaminated sites in permafrost regions. Bioavailability has been increasingly used for human health risk assessment of heavy metals in contaminated soils. Soil heavy metal bioavailability depends on soil physicochemical properties, and freeze-thaw affects soil physical, chemical and biological processes. However it is not clear whether freeze-thaw has an effect on the bioavailability of soil heavy metals. In this study, soils contaminated with Pb and As were collected from 10 industrial sites in northeast China. Extractability and bioavailability of soil Pb and As were determined by the Tessier sequential extraction method and four in vitro gastron-intestinal simulation methods under control and freeze-thaw treatments. The aims were: to compare the results of extraction and bioavailability from laboratory experiments which artificially simulate freeze-thaw conditions against control soils; to explore the correlation between bioavailability of Pb/As and soil properties. Freeze-thaw significantly decreased soil pH, and increased the soil weight surface area. Freeze-thaw decreased the percentage in the residual fraction, and increased the percentage of Pb and As in the exchangeable fraction, carbonate-bound fraction, Fe-Mn oxides-bound fraction and organic-bound fraction, relative to control soils. Freeze-thaw significantly increased Pb and As bioavailability compared to the controls. Pb and As released in the gastric phase of the four methods was significantly higher than that in the intestinal phase. Further analysis of correlations between Pb and As bioavailability and soil properties indicated that total concentrations of Al, Fe and Mn, particle size, and weight surface area significantly correlated to Pb and As bioavailability. Overall, this study demonstrated that freeze-thaw did influence the bioavailability of soil heavy metals. It suggests the freeze-thaw action should be comprehensively considered in the human risk assessment of soil pollutants in permafrost regions.
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Metales Pesados , Contaminantes del Suelo , Humanos , Plomo/análisis , Disponibilidad Biológica , Contaminación Ambiental/análisis , Metales Pesados/análisis , Suelo/química , Contaminantes del Suelo/análisisRESUMEN
Risk assessment has been recognized as an important tool for evaluating heavy metal pollution and providing risk-based information for decision makers. In order to accurately assess the risk of heavy metals in contaminated soil to human health, it is necessary to conduct bioavailability studies on heavy metals in soil. Bioavailability of heavy metals in soils and the implications for risk assessment and land management/remediation has evolved over the decades and now has considerable practical and economic implications internationally. This article aims to explore its evolution by undertaking a bibliometric analysis of the research fields which have addressed heavy metal bioavailability in soils, with a focus on the risk assessment of contaminated land and human exposure to soil-borne metals. Bibliometric analysis techniques are applied to monitor and assess the changing research literature on the bioavailability of heavy metals in contaminated soils. Over 5000 articles were found for the period 1979-2020. The purpose was not to perform an exhaustive literature review, but to draw out trends and patterns in the literature, and to make observations on past and current priorities. Key words were extracted from the analysis and the roles of different countries in driving the research literature identified. Three phases in literature/subject development were identified. Between 1979 and 2000 (initial phase, 213 articles), studies used extraction procedures and solubility studies to investigate the roles of soil properties on metal form/speciation and focused on bioavailability to (crop) plants in agricultural soils. Between 2001 and 2010 (slow development phase, 1105 articles), attention switched to metals introduced in soil amendments and wastes, metal impacts on soil microbial processes, and incorporating bioavailability in risk assessment. More rigorous techniques were being used, such as the diffusive gradients in thin films technique, to better understand kinetic and metal speciation in soils and the quantitative relationship to bioavailability. By 2011-2020 (rapid development phase, 3137 articles), research was being conducted in many countries (site specific, often industrially contaminated and urban sites), with a focus shift to health risk assessment, remediation, and bioavailability to various ecological receptors (e.g., humans and animals), with the development of many methods of bioavailability (e.g., simulated gastrointestinal tract enzymolysis methods). Some priorities for research on soil heavy metal bioavailability are identified.
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Metales Pesados , Contaminantes del Suelo , Humanos , Disponibilidad Biológica , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Medición de Riesgo , SueloRESUMEN
After thermal desorption, the total amount of heavy metals (HMs) is enriched in baghouse filter dust. To further understand the related environmental impact, the leaching characteristics under various conditions must be explored. Therefore, this study aimed to examine the leaching characteristics of seven HMs in the dust generated in the direct-fired thermal desorption process and to compare the differences in heavy metal leaching characteristics in the soil before and after thermal desorption. The leaching characteristics and bioaccessibility of seven HMs-arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn)-were analyzed in dust and in soil before and after thermal desorption. The activity of HMs in dust was strong. Therefore, environmental effects and effects on human health should be considered in the treatment of soil and dust after thermal desorption.
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Metales Pesados , Contaminantes del Suelo , Humanos , Polvo/análisis , Monitoreo del Ambiente , Contaminantes del Suelo/análisis , Medición de Riesgo , Metales Pesados/análisis , Cadmio/análisis , Suelo , ChinaRESUMEN
Hepatocellular carcinoma (HCC) is the most common primary liver tumor and one of the leading causes of cancer-related death worldwide. Chemotherapeutic agents/regimens such as cisplatin (DDP) are frequently used for advanced HCC treatment. However, drug resistance remains a major hindrance and the underline mechanisms are not fully understood. In this study, we investigated the expression pattern and function of mitochondrial fission factor (Mff) in cisplatin-resistant HCC. We found that Mff is highly expressed in cisplatin-resistant HCC tissues and cell lines. Knockdown of Mff suppresses cell proliferation and promotes cell apoptosis of HCC/DDP cells. In addition, knockdown of Mff sensitizes Huh-7/DDP cells to cisplatin treatment, inhibits cell proliferation, migration and invasion, and enhances cell apoptosis. Confocal imaging showed that knockdown of Mff inhibits the mitochondrial fission and downregulates the expression of GTPase dynamin-related protein 1 (Drp1) in cisplatin-resistant Huh-7/DDP cells. Moreover, xenograft tumor model revealed that knockdown of Mff sensitizes Huh-7/DDP xenograft tumor to cisplatin treatment . In summary, our findings suggest that Mff regulates mitochondrial Drp1 expression and promotes cisplatin resistance in HCC, which provides a potential therapeutic target for the treatment of resistant HCC.