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1.
Environ Res ; 251(Pt 2): 118645, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38485077

RESUMO

Every year, a significant amount of antimony (Sb) enters the environment from natural and anthropogenic sources like mining, smelting, industrial operations, ore processing, vehicle emissions, shooting activities, and coal power plants. Humans, plants, animals, and aquatic life are heavily exposed to hazardous Sb or antimonide by either direct consumption or indirect exposure to Sb in the environment. This review summarizes the current knowledge about Sb global occurrence, its fate, distribution, speciation, associated health hazards, and advanced biochar composites studies used for the remediation of soil contaminated with Sb to lessen Sb bioavailability and toxicity in soil. Anionic metal(loid) like Sb in the soil is significantly immobilized by pristine biochar and its composites, reducing their bioavailability. However, a comprehensive review of the impacts of biochar-based composites on soil Sb remediation is needed. Therefore, the current review focuses on (1) the fundamental aspects of Sb global occurrence, global soil Sb contamination, its transformation in soil, and associated health hazards, (2) the role of different biochar-based composites in the immobilization of Sb from soil to increase biochar applicability toward Sb decontamination. The review aids in developing advanced, efficient, and effective engineered biochar composites for Sb remediation by evaluating novel materials and techniques and through sustainable management of Sb-contaminated soil, ultimately reducing its environmental and health risks.

2.
J Environ Manage ; 347: 119018, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37748293

RESUMO

Soil contamination and its subsequent impact on the food chain is a pressing challenge in the present day. The application of biochar has demonstrated a significant and positive effect on soil health, thereby enhancing plant growth and development. However, the application of biochar (BC) produced from negative pressure-induced carbonization to mitigate metal(loid) contamination is a new strategy that has been studied in current research. Results depicted that the application of biochar derived from the negative pressure carbonization (vacuum-assisted biochar (VBC) has a significant (p ≤ 0.05) positive impact on plant growth and physiological characteristics by influencing immobilization and speciation of metal(loid) in the soil system. Moreover, the interactive effect of VBC on physiological characteristics (photosynthesis, gas exchange, and chlorophyll contents) and antioxidant activities of maize (Zea mays L.) was significantly (p ≤ 0.05) positive by confining the translocation and movement of metal(loid)s to the aerial part of the maize plant. X-ray diffraction (XRD) provided information on the structural and chemical changes induced by the VBC-500 °C explaining metal(loid) adsorption onto mineral surfaces and complexation that can affect their mobility, availability, and toxicity in the contaminated soil. Fourier transform infrared spectroscopy (FTIR) further provided a more detailed understanding of the metal(loid)s and biochar complexation mechanisms influenced by VBC-based functional groups -OH, C-Hn, -COOH, CO, C-O-C, CC, C-O, C-H, OH, and C-C in the binding process. These results suggest that the application of biochar prepared at 500 °C under negative pressure-induced carbonization conditions to the soil is the most efficient way to reduce the uptake and transfer of metal(loid)s by influencing their mobility and availability in the soil-plant system.


Assuntos
Poluentes do Solo , Poluentes do Solo/análise , Carvão Vegetal/química , Metais/análise , Solo/química , Zea mays
3.
Environ Sci Pollut Res Int ; 30(40): 92842-92858, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37495807

RESUMO

The unprecedented stride of urbanization and industrialization has given rise to anthropogenic input of tiny particulates into the air. Urban particulate matter (PM) armored with potentially toxic metals (PTMs) could be lethal to the environment and human health. Therefore, the present study was planned to investigate the spectroscopic fingerprinting, pollution status and health risk of PM-associated PTMs collected from ten functional areas of Lahore, Pakistan. The diverged results of studied qualitative and quantitative analyses showed distinct compositional and pollution characteristics of PTMs in urban PM with respect to selected functional areas. The XRD results evident the fractional presence of metal-containing minerals, i.e., pyrite (FeS2), calcite (CaCO3), zinc sulfate (ZnSO4), and chalcostibite (CuSbS2). Several chemical species of Zn, Pb, and As were found in PM of various functional areas. However, morphologies of PM showed anthropogenic influence with slight quantitative support of PTMs presence. The cumulative representation of PTMs pollution of all selected areas depicted that Cd was heavily polluted (Igeo=3.21) while Cr (Igeo=1.82) and Ni (Igeo=2.11) were moderately polluted PTMs. The industrial area having high pollution status of Cd (Igeo=5.54 and EF=18.07), Cu (Igeo=6.4 and EF=32.61), Cr (Igeo=4.03 and EF=6.53), Ni (Igeo=5.7 and EF=20.17), and Zn (Igeo=4.87 and EF=11.27) was prominent among other studied areas. The PTMs were likely to pose a high non-cancerous risk in IndAr (HI = 7.48E+00) and HTV (HI = 1.22E +00) areas predominantly due to Zn with HQ > 1. However, Cr was prominent to cause cancerous risks with values beyond the tolerable range (1.00E-04 to 1.00E-06).


Assuntos
Monitoramento Ambiental , Metais Pesados , Humanos , Monitoramento Ambiental/métodos , Material Particulado/análise , Cádmio/análise , Metais Pesados/análise , Medição de Risco , China
4.
Environ Sci Pollut Res Int ; 30(32): 78279-78293, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37269518

RESUMO

An inexpensive and environmentally friendly composite synthesized from rice husk, impregnated with montmorillonite and activated by carbon dioxide, was investigated for the removal of azithromycin from an aqueous solution. Various techniques were used to characterize adsorbents in detail. The sorption process was primarily regulated by the solution pH, pollutant concentration, contact duration, adsorbent dose, and solution temperature. The equilibrium data were best analyzed using the nonlinear Langmuir and Sips (R2 > 0.97) isotherms, which revealed that adsorption occurs in a homogenous manner. The adsorption capacity of pristine biochar and carbon dioxide activated biochar-montmorillonite composite was 33.4 mg g-1 and 44.73 mg g-1, respectively. Kinetic studies identified that the experimental data obeyed the pseudo-second-order and Elovich models (R2 > 0.98) indicating the chemisorption nature of adsorbents. The thermodynamic parameters determined the endothermic and spontaneous nature of the reaction. The ion exchange, π-π electron-donor-acceptor (EDA) interactions, hydrogen-bonding, and electrostatic interactions were the plausible mechanisms responsible for the adsorption process. This study revealed that a carbon dioxide activated biochar-montmorillonite composite may be used as an effective, sustainable, and economical adsorbent for the removal of azithromycin from polluted water.


Assuntos
Bentonita , Poluentes Químicos da Água , Azitromicina , Cinética , Dióxido de Carbono , Poluentes Químicos da Água/análise , Carvão Vegetal/química , Termodinâmica , Água , Adsorção , Concentração de Íons de Hidrogênio
5.
J Environ Manage ; 325(Pt B): 116620, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323123

RESUMO

The structure of biochar produced at various pyrolysis temperatures influences metal geochemical behavior. Here, the impact of wheat straw-derived biochar (300, 500, and 700 °C) on the immobilization and transformation of metals in the contaminated soil-plant system was assessed. The findings of the sequential extraction revealed that biochar additives had a substantial influence on the speciation of Cr, Ni, Pb, and Zn in the contaminated soil. The lowest F1 (exchangeable and soluble fraction) + F2 (carbonate fraction) accounted for Cr (44%) in WB-300, Ni (43.87%) in WB-500, Pb (43.79%), and Zn (49.78%) in WB-700 with applied amendments of their total amounts. The characterization results indicated that high pyrolysis temperatures (300-700 °C) increased the carbon-containing groups with the potential to adsorb metals from the soil-plant environment. The bioconcentration and translocation factors (BCF and TF) were less than 1, indicating that metal concentration was restricted to maize roots and translocation to shoots. Reactive oxygen species (ROS) intracellularly influence metal interactions with plants. Electron paramagnetic resonance (EPR) was performed to determine hydroxyl radical generation (•OH) in plant segments to assess the dominance of free radicals (FRs). Consequently, the formation of •OH significantly depends on the pyrolysis temperature and the interaction with a contaminated soil-plant environment. Thus, metal transformation can be effectively decreased in the soil-plant environment by applying WB amendments.


Assuntos
Metais Pesados , Poluentes do Solo , Poluentes do Solo/análise , Chumbo , Carvão Vegetal/química , Solo/química , Metais Pesados/química , Radicais Livres
6.
Environ Sci Pollut Res Int ; 30(3): 6216-6233, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35989404

RESUMO

Heavy metal contamination has increased over the globe, causing significant environmental issues owing to direct and indirect releases into water bodies. As a result, metal removal from water entities must be addressed soon. Various adsorbents such as MOFs and chitosan have demonstrated promising results in water treatment. The present study prepared a composite material (chitosan-UiO-66-glycidyl methacrylate MOF) by a microwave-assisted method. The structure and morphology of the chitosan-MOF composite were studied using FE-SEM, EDX, XRD, BET, FT-IR, and TGA techniques. In addition, the adsorption of Pb(II) from aqueous solution onto the chitosan-MOF composite was analyzed in a batch study concerning pH, contact time, initial metal ion concentration, and adsorbent dosage. The composite has a large surface area of 867 m2/g with a total pore volume of 0.51 cm3/g and thermal stability of up to 400 [Formula: see text]. Following an analysis of the adsorption isotherms, kinetics, and thermodynamics, the Langmuir model showed an excellent fit with the adsorption data (R2 = 0.99) and chi-squared (X2 = 3.609). The adsorption process was a spontaneous exothermic reaction and the pseudo-second-order rate equation fitted the kinetic profile well. Moreover, the composite is recyclable, retaining 83.45% of its removal effectiveness after 5 consecutive cycles, demonstrating it as a sustainable adsorbent for metal recovery. This study introduces a novel synthesized composite with enhanced recyclability and a higher potential for eliminating pollutants from industrial wastewater.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Chumbo , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Micro-Ondas , Cinética , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio , Purificação da Água/métodos
7.
Ann Oper Res ; : 1-25, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36338350

RESUMO

Fake news and disinformation (FNaD) are increasingly being circulated through various online and social networking platforms, causing widespread disruptions and influencing decision-making perceptions. Despite the growing importance of detecting fake news in politics, relatively limited research efforts have been made to develop artificial intelligence (AI) and machine learning (ML) oriented FNaD detection models suited to minimize supply chain disruptions (SCDs). Using a combination of AI and ML, and case studies based on data collected from Indonesia, Malaysia, and Pakistan, we developed a FNaD detection model aimed at preventing SCDs. This model based on multiple data sources has shown evidence of its effectiveness in managerial decision-making. Our study further contributes to the supply chain and AI-ML literature, provides practical insights, and points to future research directions.

8.
Environ Pollut ; 315: 120335, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36202269

RESUMO

Potentially toxic metals have become a viable threat to the ecosystem due to their carcinogenic nature. Biochar has gained substantial interest due to its redox-mediated processes and redox-active metals. Biochar has the capacity to directly adsorb the pollutants from contaminated environments through several mechanisms such as coprecipitation, complexation, ion exchange, and electrostatic interaction. Biochar's electron-mediating potential may be influenced by the cyclic transition of surface moieties and conjugated carbon structures. Thus, pyrolysis configuration, biomass material, retention time, oxygen flow, and heating time also affect biochar's redox properties. Generally, reactive oxygen species (ROS) exist as free radicals (FRs) in radical and non-radical forms, i.e., hydroxyl radical, superoxide, nitric oxide, hydrogen peroxide, and singlet oxygen. Heavy metals are involved in the production of FRs during redox-mediated reactions, which may contribute to ROS formation. This review aims to critically evaluate the redox-mediated characteristics of biochar produced from various biomass feedstocks under different pyrolysis conditions. In addition, we assessed the impact of biochar-assisted FRs redox-mediated processes on heavy metal immobilization and mobility. We also revealed new insights into the function of FRs in biochar and its potential uses for environment-friendly remediation and reducing the dependency on fossil-based materials, utilizing local residual biomass as a raw material in terms of sustainability.


Assuntos
Metais Pesados , Poluentes do Solo , Espécies Reativas de Oxigênio , Ecossistema , Carvão Vegetal/química , Metais Pesados/análise , Radicais Livres , Oxirredução , Solo/química
9.
Environ Sci Pollut Res Int ; 29(22): 32513-32544, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35190984

RESUMO

Erythromycin (ERY), designated as a risk-prioritized macrolide antibiotic on the 2015 European Union watch list, is the third most commonly used antibiotic, most likely due to its ability to inhibit the protein. ERY has revealed record-high aquatic concentrations threatening the entire ecosystem and hence demands priority remedial measures. The inefficiency of various conventional ERY degradation methodologies opened up a gateway to advanced technologies. The conventional approach comprising of a chemically formulated, single photocatalyst has a major drawback of creating multiple environmental stresses. In this context, photocatalysis is grabbing tremendous attention as an efficient and cost-effective antibiotic treatment approach. Several studies have ascertained that ZnO, TiO2, Fe3O4, and rGO nanoparticles possess remarkable pollution minimizing operational capabilities. Additionally, composites are found much more effective in antibiotic removal than single nanoparticles. In this review, an attempt has been made to provide a comprehensive baseline for efficient reactive radical production by a phyto-mediated composite kept under a certain source of irradiation. Considerable efforts have been directed towards the in-depth investigation of rGO-embedded, phyto-mediated ZnO/TiO2/Fe3O4 photocatalyst fabrication for efficient ERY degradation, undergoing green photocatalysis. This detailed review provides photocatalytic nanocomposite individualities along with a hypothetical ERY degradation mechanism. It is assumed that derived information presented here will provoke innovative ideas for water purification incorporating green photocatalysis, initiating the construction of high-performance biogenic hierarchical nanocatalysts.


Assuntos
Purificação da Água , Óxido de Zinco , Antibacterianos , Catálise , Ecossistema , Eritromicina
10.
Sci Total Environ ; 772: 145389, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578171

RESUMO

Wide spread documentation of antibiotic pollution is becoming a threat to aquatic environment. Erythromycin (ERY), a macrolide belonging antibiotic is at the top of this list with its concentrations ranging between ng/L to a few µg/L in various global waterbodies giving rise to ERY-resistance genes (ERY-RGs) and ERY- resistance bacteria (ERY-RBs) posing serious threat to the aquatic organisms. ERY seems resistant to various conventional water treatments, remained intact and even increased in terms of mass loads after treatment. Enhanced oxidation potential, wide pH range, elevated selectivity, adaptability and greater efficiency makes advance oxidation processes (AOPs) top priority for degrading pollutants with aromatic rings and unsaturated bonds like ERY. In this manuscript, recent developments in AOPs for ERY degradation are reported along with the factors that affect the degradation mechanism. ERY, marked as a risk prioritized macrolide antibiotic by 2015 released European Union watch list, most probably due to its protein inhibition capability considered third most widely used antibiotic. The current review provides a complete ERY overview including the environmental entry sources, concentration in global waters, ERY status in STPs, as well as factors affecting their functionality. Along with that this study presents complete outlook regarding ERY-RGs and provides an in depth detail regarding ERY's potential threats to aquatic biota. This study helps in figuring out the best possible strategy to tackle antibiotic pollution keeping ERY as a model antibiotic because of extreme toxicity records.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Antibacterianos , Ecossistema , Eritromicina , Oxirredução , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
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