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1.
J Environ Sci (China) ; 147: 22-35, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39003042

ABSTRACT

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 (•O2- and •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.


Subject(s)
Clay , Environmental Restoration and Remediation , Soil Pollutants , Soil , Clay/chemistry , Soil/chemistry , Catalysis , Soil Pollutants/chemistry , Environmental Restoration and Remediation/methods , Hot Temperature
2.
J Environ Sci (China) ; 147: 424-450, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39003060

ABSTRACT

The electrokinetic (EK) process has been proposed for soil decontamination from heavy metals and organic matter. The advantages of the EK process include the low operating energy, suitability for fine-grained soil decontamination, and no need for excavation. During the last three decades, enhanced and hybrid EK systems were developed and tested for improving the efficiency of contaminants removal from soils. Chemically enhanced-EK processes exhibited excellent efficiency in removing contaminants by controlling the soil pH or the chemical reaction of contaminants. EK hybrid systems were tested to overcome environmental hurdles or technical drawbacks of decontamination technologies. Hybridization of the EK process with phytoremediation, bioremediation, or reactive filter media (RFM) improved the remediation process performance by capturing contaminants or facilitating biological agents' movement in the soil. Also, EK process coupling with solar energy was proposed to treat off-grid contaminated soils or reduce the EK energy requirements. This study reviews recent advancements in the enhancement and hybrid EK systems for soil remediation and the type of contaminants targeted by the process. The study also covered the impact of operating parameters, imperfect pollution separation, and differences in the physicochemical characteristics and microstructure of soil/sediment on the EK performance. Finally, a comparison between various remediation processes was presented to highlight the pros and cons of these technologies.


Subject(s)
Environmental Restoration and Remediation , Metals, Heavy , Soil Pollutants , Soil , Soil Pollutants/chemistry , Environmental Restoration and Remediation/methods , Soil/chemistry , Biodegradation, Environmental
3.
J Environ Sci (China) ; 147: 474-486, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39003063

ABSTRACT

Nano zero-valent iron (nZVI) is widely used in soil remediation due to its high reactivity. However, the easy agglomeration, poor antioxidant ability and passivation layer of Fe-Cr coprecipitates of nZVI have limited its application scale in Cr-contaminated soil remediation, especially in high concentration of Cr-contaminated soil. Herein, we found that the carboxymethyl cellulose on nZVI particles could increase the zeta potential value of soil and change the phase of nZVI. Along with the presence of biochar, 97.0% and 96.6% Cr immobilization efficiency through CMC-nZVI/BC were respectively achieved in high and low concentrations of Cr-contaminated soils after 90-days remediation. In addition, the immobilization efficiency of Cr(VI) only decreased by 5.1% through CMC-nZVI/BC treatment after 10 weeks aging in air, attributing to the strong antioxidation ability. As for the surrounding Cr-contaminated groundwater, the Cr(VI) removal capacity of CMC-nZVI/BC was evaluated under different reaction conditions through column experiments and COMSOL Multiphysics. CMC-nZVI/BC could efficiently remove 85% of Cr(VI) in about 400 hr when the initial Cr(VI) concentration was 40 mg/L and the flow rate was 0.5 mL/min. This study demonstrates that uniformly dispersed CMC-nZVI/BC has an excellent remediation effect on different concentrations of Cr-contaminated soils.


Subject(s)
Carboxymethylcellulose Sodium , Charcoal , Chromium , Environmental Restoration and Remediation , Iron , Soil Pollutants , Soil Pollutants/chemistry , Charcoal/chemistry , Environmental Restoration and Remediation/methods , Iron/chemistry , Chromium/chemistry , Carboxymethylcellulose Sodium/chemistry , Soil/chemistry , Metal Nanoparticles/chemistry
4.
J Environ Sci (China) ; 147: 652-664, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39003080

ABSTRACT

Ball milling is an environmentally friendly technology for the remediation of petroleum-contaminated soil (PCS), but the cleanup of organic pollutants requires a long time, and the post-remediation soil needs an economically viable disposal/reuse strategy due to its vast volume. The present paper develops a ball milling process under oxygen atmosphere to enhance PCS remediation and reuse the obtained carbonized soil (BCS-O) as wastewater treatment materials. The total petroleum hydrocarbon removal rates by ball milling under vacuum, air, and oxygen atmospheres are 39.83%, 55.21%, and 93.84%, respectively. The Langmuir and pseudo second-order models satisfactorily describe the adsorption capacity and behavior of BCS-O for transition metals. The Cu2+, Ni2+, and Mn2+ adsorbed onto BCS-O were mainly bound to metal carbonates and metal oxides. Furthermore, BCS-O can effectively activate persulfate (PDS) oxidation to degrade aniline, while BCS-O loaded with transition metal (BCS-O-Me) shows better activation efficiency and reusability. BCS-O and BCS-O-Me activated PDS oxidation systems are dominated by 1O2 oxidation and electron transfer. The main active sites are oxygen-containing functional groups, vacancy defects, and graphitized carbon. The oxygen-containing functional groups and vacancy defects primarily activate PDS to generate 1O2 and attack aniline. Graphitized carbon promotes aniline degradation by accelerating electron transfer. The paper develops an innovative strategy to simultaneously realize efficient remediation of PCS and sequential reuse of the post-remediation soil.


Subject(s)
Environmental Restoration and Remediation , Oxygen , Petroleum , Soil Pollutants , Waste Disposal, Fluid , Wastewater , Soil Pollutants/chemistry , Soil Pollutants/analysis , Adsorption , Wastewater/chemistry , Oxygen/chemistry , Oxygen/analysis , Waste Disposal, Fluid/methods , Environmental Restoration and Remediation/methods , Soil/chemistry , Catalysis
5.
J Environ Sci (China) ; 147: 630-641, 2025 Jan.
Article in English | MEDLINE | ID: mdl-39003078

ABSTRACT

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.


Subject(s)
Arsenic , Cadmium , Charcoal , Magnesium , Oryza , Soil Pollutants , Soil , Oryza/chemistry , Cadmium/analysis , Cadmium/chemistry , Charcoal/chemistry , Soil Pollutants/analysis , Arsenic/analysis , Soil/chemistry , Magnesium/chemistry , Iron/chemistry , Environmental Restoration and Remediation/methods
6.
Int J Mol Sci ; 25(14)2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39063063

ABSTRACT

Mining of organophosphorous (OPs)-degrading bacterial enzymes in collections of known bacterial strains and in natural biotopes are important research fields that lead to the isolation of novel OP-degrading enzymes. Then, implementation of strategies and methods of protein engineering and nanobiotechnology allow large-scale production of enzymes, displaying improved catalytic properties for medical uses and protection of the environment. For medical applications, the enzyme formulations must be stable in the bloodstream and upon storage and not susceptible to induce iatrogenic effects. This, in particular, includes the nanoencapsulation of bioscavengers of bacterial origin. In the application field of bioremediation, these enzymes play a crucial role in environmental cleanup by initiating the degradation of OPs, such as pesticides, in contaminated environments. In microbial cell configuration, these enzymes can break down chemical bonds of OPs and usually convert them into less toxic metabolites through a biotransformation process or contribute to their complete mineralization. In their purified state, they exhibit higher pollutant degradation efficiencies and the ability to operate under different environmental conditions. Thus, this review provides a clear overview of the current knowledge about applications of OP-reacting enzymes. It presents research works focusing on the use of these enzymes in various bioremediation strategies to mitigate environmental pollution and in medicine as alternative therapeutic means against OP poisoning.


Subject(s)
Biodegradation, Environmental , Organophosphorus Compounds , Organophosphorus Compounds/metabolism , Humans , Environmental Restoration and Remediation/methods , Bacteria/enzymology , Organophosphate Poisoning/drug therapy , Pesticides/metabolism , Pesticides/chemistry , Pesticides/toxicity
7.
Environ Geochem Health ; 46(8): 275, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38958819

ABSTRACT

Soil organic matter plays an important role in cadmium adsorption and immobilization. Since different organic matter components affect cadmium adsorption processes differently, selecting the right organic substrate and knowing how to apply it could improve cadmium remediation. This study compares the effects of two contrasting organic molecules; chitosan and citric acid, on cadmium adsorption and speciation in acidic Ultisol. The adsorption of chitosan to Ultisol significantly increased the soil positive charge while adsorption of citric acid increased the soil negative charge. At pH 5.0, the maximum amount of cadmium adsorbed in excess chitosan was 341% greater than that in excess citric acid. About 73-89% and 60-62% of adsorbed cadmium were bound to Fe/Mn oxides and organic matter/sulfide at pH 4.0 while this fraction was 77-100% and 57-58% for citric acid and chitosan at pH 5.0, respectively. This decrease in the complexing ability of chitosan was related to the destabilizing effect of high pH on chitosan's structure. Also, the sequence through which chitosan, citric acid, and cadmium were added into the adsorption system influenced the adsorption profile and this was different along a pH gradient. Specifically, adding chitosan and cadmium together increased adsorption compared to when chitosan was pre-adsorbed within pH 3.0-6.5. However, for citric acid, the addition sequence had no significant effect on cadmium adsorption between pH 3.0-4.0 compared to pH 6.5 and 7.5, with excess citric acid generally inhibiting adsorption. Given that the action of citric acid is short-lived in soil, chitosan could be a good soil amendment material for immobilizing cadmium.


Subject(s)
Cadmium , Chitosan , Citric Acid , Soil Pollutants , Soil , Chitosan/chemistry , Citric Acid/chemistry , Cadmium/chemistry , Adsorption , Soil Pollutants/chemistry , Soil/chemistry , Hydrogen-Ion Concentration , Environmental Restoration and Remediation/methods
8.
Environ Geochem Health ; 46(9): 307, 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39002001

ABSTRACT

This study aimed to assess the effectiveness of urban derived biochars such as Sugarcane bagasse (SB), Brinjal Stem (BS), and Citrus Peel (CP) produced at two different pyrolysis conditions (450 and 600 °C for 60 min) for soil heavy metal bioremediation potential. An ex-situ study was conducted to remediate single heavy metal-contaminated SoilRite with lead (Pb), copper (Cu), chromium (Cr) and cadmium (Cd), with biochars applied at different rates. Heavy metal status in soilrite was evaluated using various extraction methods (water-soluble, exchangeable, TCLP (Toxicity Characteristic Leaching Procedure), and PBET (Physiologically Based Extraction Tests)) to determine the biochar treatments' efficacy. The findings show that SB biochar at 450-60 are more effective in immobilizing heavy metals in water-soluble (Cd-100% Pb and Cu-70%), exchangeable (Pb:91%, Cd and Cu by 70-80%) and PBET-extracted forms (Cd-91%, Pb-80%, and Cu-75%), whereas biochar derived from BS (84%) and CP (90%) at 600-60 are more effective in immobilizing TCLP-extracted form of Pb and Cu. Urban derived biochars significantly reduced the toxicity of Pb, Cu, and Cd in various extractable forms and can stabilize and convert them into less accessible forms except for Cr. These extraction methods aid in evaluating environmental risks and influencing remediation strategies for soil heavy metal pollution. Urban biochar, as a cost-effective and eco-friendly solution, significantly solves this issue, facilitating sustainable waste management.


Subject(s)
Charcoal , Environmental Restoration and Remediation , Metals, Heavy , Pyrolysis , Soil Pollutants , Charcoal/chemistry , Soil Pollutants/chemistry , Soil Pollutants/analysis , Metals, Heavy/chemistry , Metals, Heavy/analysis , Environmental Restoration and Remediation/methods , Citrus/chemistry , Saccharum/chemistry , Soil/chemistry , Biodegradation, Environmental
9.
J Environ Manage ; 365: 121716, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38968897

ABSTRACT

In this study, a novel piezoremediation system was developed to remediate an actual soil co-polluted by high contents of per- and polyfluoroalkyl substances (PFAS, 5725 µg/kg soil) and heavy metals (6455 mg/kg soil). Two piezocatalysts, MoS2/ceramsite (MC) and Fe3O4-MoS2/ceramsite (FMC), were synthesized using a facile hydrothermal-coprecipitation method. These two materials were employed to treat the co-contaminated soil in soil slurry environment under sonication. FMC exhibited significantly higher piezoremediation performance than MC, wherein 91.6% of PFAS, 97.8% of Cr6+ ions and 81% of total metals (Cr, Cu, Zn and Ni) were removed from the soil after 50 min of the FMC piezoremediation process. FMC also exhibited the advantages of easy separation from the slurry phase and excellent reusability. In comparison with MC, the Fe3O4-MoS2 heterojunction in FMC can stabilize MoS2 particles on the surface of ceramsite granules, promote the separation of electron/hole pairs, accelerate charge transfer, therefore enhancing piezocatalytic performance. The electron spin resonance analysis and free radical quenching tests show that •OH was the dominant oxidative radical responsible for PFAS degradation. The count of bacteria and the bacterial community structure in the treated soil can be basically restored to the initial states after 30 days of incubation under nutrient stimulation. Overall, this study not only provides a deep insight on soil remediation process, but also offers an efficient and reliable technique for simultaneous decontamination of organic and metal pollutants in soil.


Subject(s)
Metals, Heavy , Soil Pollutants , Soil , Soil Pollutants/chemistry , Soil Pollutants/metabolism , Soil/chemistry , Metals, Heavy/chemistry , Environmental Restoration and Remediation/methods , Biodegradation, Environmental
10.
Environ Geochem Health ; 46(8): 290, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38976075

ABSTRACT

Heavy metal pollution is a significant environmental concern with detrimental effects on ecosystems and human health, and traditional remediation methods may be costly, energy-intensive, or have limited effectiveness. The current study aims were to investigate the impact of heavy metal toxicity in Eisenia fetida, the growth, reproductive outcomes, and their role in soil remediation. Various concentrations (ranging from 0 to 640 mg per kg of soil) of each heavy metal were incorporated into artificially prepared soil, and vermi-remediation was conducted over a period of 60 days. The study examined the effects of heavy metals on the growth and reproductive capabilities of E. fetida, as well as their impact on the organism through techniques such as FTIR, histology, and comet assay. Atomic absorption spectrometry demonstrated a significant (P < 0.000) reduction in heavy metal concentrations in the soil as a result of E. fetida activity. The order of heavy metal accumulation by E. fetida was found to be Cr > Cd > Pb. Histological analysis revealed a consistent decline in the organism's body condition with increasing concentrations of heavy metals. However, comet assay results indicated that the tested levels of heavy metals did not induce DNA damage in E. fetida. FTIR analysis revealed various functional group peaks, including N-H and O-H groups, CH2 asymmetric stretching, amide I and amide II, C-H bend, carboxylate group, C-H stretch, C-O stretching of sulfoxides, carbohydrates/polysaccharides, disulfide groups, and nitro compounds, with minor shifts indicating the binding or accumulation of heavy metals within E. fetida. Despite heavy metal exposure, no significant detrimental effects were observed, highlighting the potential of E. fetida for sustainable soil remediation. Vermi-remediation with E. fetida represents a novel, sustainable, and cutting-edge technology in environmental cleanup. This study found that E. fetida can serve as a natural and sustainable method for remediating heavy metal-contaminated soils, promising a healthier future for soil.


Subject(s)
Environmental Restoration and Remediation , Metals, Heavy , Oligochaeta , Reproduction , Soil Pollutants , Oligochaeta/drug effects , Metals, Heavy/toxicity , Animals , Soil Pollutants/toxicity , Reproduction/drug effects , Environmental Restoration and Remediation/methods , Comet Assay , Spectroscopy, Fourier Transform Infrared , DNA Damage , Soil/chemistry
11.
Environ Geochem Health ; 46(8): 289, 2024 Jul 06.
Article in English | MEDLINE | ID: mdl-38970698

ABSTRACT

Low molecular weight organic acids (LMWOAs) are important soil components and play a key role in regulating the geochemical behavior of heavy metal(loid)s. Biochar (BC) is a commonly used amendment that could change LMWOAs in soil. Here, four LMWOAs of oxalic acid (OA), tartaric acid (TA), malic acid (MA), and citric acid (CA) were evaluated for their roles in changing Cd and SB desorption behavior in contaminated soil with (S1-BC) or without BC (S1) produced from Paulownia biowaste. The results showed that OA, TA, MA, and CA reduced soil pH with rising concentrations, and biochar partially offset the pH reduction by LMWOAs. The LMWOAs reduced Cd desorption from the soil at low concentrations but increased Cd desorption at high concentrations, and CA was the most powerful in this regard. The LMWOAs had a similar effect on Sb desorption, and CA was the most effective species of LMWOAs. Adding BC to the soil affects Cd and Sb dynamics by reducing the Cd desorption but increasing Sb desorption from the soil and increasing the distribution coefficient (Kd) values of Cd but lowering the Kd values of Sb. This study helped understand the effects of LMWOAs on the geochemical behavior of Cd and Sb in the presence of biochar, as well as the potential risks of biochar amendment in enhancing Sb desorption from contaminated soil.


Subject(s)
Charcoal , Metals, Heavy , Soil Pollutants , Soil , Charcoal/chemistry , Soil Pollutants/chemistry , Metals, Heavy/chemistry , Soil/chemistry , Molecular Weight , Hydrogen-Ion Concentration , Cadmium/chemistry , Tartrates/chemistry , Malates/chemistry , Citric Acid/chemistry , Environmental Restoration and Remediation/methods , Oxalic Acid/chemistry , Adsorption , Oryza/chemistry
12.
Environ Monit Assess ; 196(8): 754, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39031225

ABSTRACT

In the contemporary landscape, the reuse of wastewater holds paramount significance. Concurrently, wastewater carries an array of pollutants encompassing chemical dyes and heavy metals. This study delves into the potential of Tamarix aphylla (TA) and Eucalyptus camaldulensis (EC) species for mitigating heavy metals in soil and eliminating methylene blue dye (MB) from wastewater. The research begins with assessing the dye adsorption process, considering pivotal factors such as initial pH, adsorbent dosage, initial dye concentration, and contact time. Outcomes reveal EC's superiority in dye removal compared to TA. As a bioremediation agent, EC exhibits a 90.46% removal efficacy for MB within 15 min, with pH 7.0 as the operative condition. Equilibrium analysis employs Temkin (T), Freundlich (F), and Langmuir (L) isotherms, revealing an excellent fit with the L isotherm model. The study delves further by probing surface adsorption kinetics through pseudo-first-order (PFO) and pseudo-second-order (PSO) models. Furthermore, to discern the divergent impacts of EC and TA on soil heavy metal reduction, soil samples were collected from three distinct zones: an untouched control area, alongside areas where EC and TA were cultivated at the Yazd wastewater site in Iran. Heavy metal levels in the soil were meticulously assessed through rigorous measurement and statistical scrutiny. The findings spotlight TA-cultivated soil as having the highest levels across all examined factors. Ultimately, EC emerges as the superior contender, proficiently excelling in both MB eliminations from wastewater and heavy metal amelioration in the soil, positioning it as the preferred phytoremediation agent.


Subject(s)
Biodegradation, Environmental , Eucalyptus , Metals, Heavy , Methylene Blue , Soil Pollutants , Soil , Tamaricaceae , Wastewater , Water Pollutants, Chemical , Eucalyptus/chemistry , Metals, Heavy/analysis , Wastewater/chemistry , Soil Pollutants/analysis , Water Pollutants, Chemical/analysis , Methylene Blue/chemistry , Soil/chemistry , Adsorption , Waste Disposal, Fluid/methods , Environmental Restoration and Remediation/methods
13.
J Contam Hydrol ; 265: 104392, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38954926

ABSTRACT

More than 60% of worldwide uranium production is based on the In Situ Recovery mining technique. This exploitation method directly falls within the scope of the applications of reactive transport modelling to optimize uranium production and limit its associated environmental impact. We propose a modelling approach which is able to represent the natural evolution of an aquifer impacted by an ISR test performed using sulfuric acid. The model is calibrated on a 12 year-long data series obtained from 12 monitoring wells surrounding an ISR pilot cell. Through this process-based approach, we simulate the impact of several remediation strategies that can be considered in these contexts. In particular, we model the impact of Pump & Treat combined with reverse osmosis, as well as the circulation of non-impacted fluids through the reservoir with different operating strategies. Our approach allows to compare the effectiveness of these strategies. For this small-scale ISR pilot, monitored natural attenuation constitutes an interesting approach due to its faster pH recovery time with respect to Pump & Treat (5-10 years to pH ∼ 6), whose efficiency can be improved by the addition of exchangeable cations. Circulation of unimpacted fluids can reduce pH recovery times if performed for periods longer than the ISR exploitation and/or deployed with a delay. Combined with an economic evaluation of their deployment, this modelling approach can help the mining operator select and design optimal remediation strategies from an environmental and economical standpoint.


Subject(s)
Environmental Restoration and Remediation , Groundwater , Models, Theoretical , Uranium , Environmental Restoration and Remediation/methods , Mining , Water Pollutants, Radioactive , Sulfuric Acids/chemistry
14.
Sci Total Environ ; 946: 174385, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-38960194

ABSTRACT

With an increase of diverse contaminants in the environment, particularly antibiotics, the maintenance and propagation of antibiotic resistance genes (ARGs) are promoted by co-selection mechanisms. ARGs are difficult to degrade, cause long-lasting pollution, and are widely transmitted in aquatic environments. Biochar is frequently used to remove various pollutants during environmental remediation. Thus, this review provides a thorough analysis of the current state of ARGs in the aquatic environment as well as their removal by using biochar. This article summarizes the research and application of biochar and modified biochar to remove ARGs in aquatic environments, in order to refine the following contents: 1) fill gaps in the research on the various ARG behaviors mediated by biochar and some influence factors, 2) further investigate the mechanisms involved in effects of biochar on extracellular ARGs (eARGs) and intracellular ARGs (iARGs) in aquatic environments, including direct and the indirect effects, 3) describe the propagation process and resistance mechanisms of ARGs, 4) propose the challenges and prospects of feasibility of application and subsequent treatment in actual aquatic environment. Here we highlight the most recent research on the use of biochar to remove ARGs from aquatic environments and suggest future directions for optimization, as well as current perspectives to guide future studies on the removal of ARGs from aquatic environments.


Subject(s)
Charcoal , Drug Resistance, Microbial , Drug Resistance, Microbial/genetics , Environmental Restoration and Remediation/methods , Anti-Bacterial Agents , Water Pollutants, Chemical
15.
Sci Total Environ ; 946: 174448, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-38969120

ABSTRACT

Afforestation is a crucial pathway for ecological restoration and has the potential to modify soil microbial community, thereby impacting the cycling and accumulation of carbon in soil across diverse patterns. However, the overall patterns of how afforestation impacts below-ground carbon cycling processes remain uncertain. In this comprehensive meta-analysis, we systematically evaluated 7045 observations from 210 studies worldwide to evaluate the influence of afforestation on microbial communities, enzyme activities, microbial functions, and associated physicochemical properties of soils. Afforestation increases microbial biomass, carbon and nitrogen hydrolase activities, and microbial respiration, but not carbon oxidase activity and nitrogen decomposition rate. Conversely, afforestation leads to a reduction in the metabolic quotient, with significant alteration of bacterial and fungal community structures and positive effects on the fungi: bacteria ratio rather than alpha and beta diversity metrics. We found a total 77 % increase in soil organic carbon (SOC) content after afforestation, which varied depending on initial SOC content before afforestation, afforestation stand age, and aridity index of afforestation sites. The modified SOC is associated with bacterial community composition along with intracellular metabolic quotient and extracellular carbon degrading enzyme activity playing a role. These findings provide insights into the pathways through which afforestation affects carbon cycling via microorganisms, thus improving our knowledge of soil carbon reservoir's responses to afforestation under global climate change.


Subject(s)
Carbon , Forests , Soil Microbiology , Soil , Carbon/analysis , Carbon Cycle , Climate Change , Environmental Restoration and Remediation/methods , Microbiota , Soil/chemistry
16.
Environ Sci Pollut Res Int ; 31(31): 44415-44430, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38954338

ABSTRACT

Chemical oxidation coupled with microbial remediation has attracted widespread attention for the removal of polycyclic aromatic hydrocarbons (PAHs). Among them, the precise evaluation of the feasible oxidant concentration of PAH-contaminated soil is the key to achieving the goal of soil functional ecological remediation. In this study, phenanthrene (PHE) was used as the target pollutant, and Fe2+-activated persulphate (PS) was used to remediate four types of soils. Linear regression analysis identified the following important factors influencing remediation: PS dosage and soil PHE content for PHE degradation, Fe2+ dosage, hydrolysable nitrogen (HN), and available phosphorus for PS decomposition. A comprehensive model of "soil characteristics-oxidation conditions-remediation effect" with a high predictive accuracy was constructed. Based on model identification, Pseudomonas aeruginosa GZ7, which had high PAHs degrading ability after domestication, was further applied to coupling repair remediation. The results showed that the optimal PS dose was 0.75% (w/w). The response relationship between soil physical, chemical, and biological indicators at the intermediate interface and oxidation conditions was analysed. Coupled remediation effects were clarified using microbial diversity sequencing. The introduction of Pseudomonas aeruginosa GZ7 stimulated the relative abundance of Cohnella, Enterobacter, Paenibacillus, and Bacillus, which can promote material metabolism and energy transformation during remediation.


Subject(s)
Oxidation-Reduction , Phenanthrenes , Pseudomonas aeruginosa , Soil Pollutants , Soil , Phenanthrenes/metabolism , Soil/chemistry , Soil Microbiology , Environmental Restoration and Remediation/methods , Biodegradation, Environmental , Polycyclic Aromatic Hydrocarbons , Sulfates/chemistry
17.
Environ Sci Pollut Res Int ; 31(32): 45162-45176, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38958859

ABSTRACT

Virgin and environmentally aged polypropylene (PP) micropowders (V-PP and E-PP, respectively) were used as reference microplastics (MPs) in comparative photo- and thermo-oxidative ageing experiments performed on their mixtures with a natural ferrous sand (NS) and with a metal-free silica sand (QS). The ferrous NS was found to catalyze the photo-oxidative degradation of V-PP after both UV and simulated solar light irradiation. The catalytic activity in the V-PP/NS mixture was highlighted by the comparatively higher fraction of photo-oxidized PP extracted in dichloromethane, and the higher carbonyl index of the bulk polymer extracted with boiling xylene, when compared with the V-PP/QS mixture. Similarly, NS showed a catalytic effect on the thermal degradation (at T = 60 °C) of E-PP. The results obtained indicate that, under suitable environmental conditions (in this case, an iron-containing sediment or soil matrix, combined with simulated solar irradiation), the degradation of some types of MPs could be much faster than anticipated. Given the widespread presence of iron minerals (including the magnetite and iron-rich serpentine found in NS) in both coastal and mainland soils and sediments, a higher than expected resilience of the environment to the contamination by this class of pollutants is anticipated, and possible routes to remediation of polluted natural environments by eco-compatible iron-based minerals are envisaged.


Subject(s)
Iron , Microplastics , Polypropylenes , Polypropylenes/chemistry , Microplastics/chemistry , Iron/chemistry , Catalysis , Minerals/chemistry , Environmental Restoration and Remediation , Oxidation-Reduction
18.
Health Phys ; 127(3): 392-403, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39052874

ABSTRACT

ABSTRACT: Completely randomized experimental design statistical modeling techniques were employed to analyze exposure rate measurements for evaluating hypothetical natural background post uranium mill operations at Coles Hill, Virginia uranium milling processes. The proposed Coles Hill Uranium Mine is situated upstream of the Banister River. This River is nearly homogenous throughout the reach length used in analysis and feeds into the mouth of Kerr Reservoir, Lake Gaston, which serves as the main drinking water source for cities in the Hampton Roads area including Norfolk, Virginia Beach, and Chesapeake. A critical scan value (=DCGLscan) was developed to flag anomalies of surface contamination during simulated post remediation final status surveys. The natural background was critical for meeting the Multi-Agency Radiation Survey and Site Investigation Manual guidance for post remediation final status surveys. The overarching null hypothesis suggested that the selected mean natural background is equal to the survey unit's mean natural background. Using SAS Procedures Shapiro-Wilk Test, ANOVA, and CR, it was decided the exposure rate data was normal, had no extreme outliers, and no collinearity between the number of samples (=treatment) and the areas (=block). Using the q-hyper (hypergeometric) distribution, the soil sampling density was decided for a final status survey unit. The most likely worst-case catastrophic failure analysis, 500-year event, such as the1969 Hurricane Camille of 69 centimeters of rain in Nelson County, Virginia was included in the model. The model showed impact was minimal at most to the Banister River's drinking water and likely less than the Virginia's Drinking Water Standards for gross alpha, 226Ra and 228Ra, and total uranium.


Subject(s)
Mining , Uranium , Virginia , Uranium/analysis , Gamma Rays , Environmental Restoration and Remediation , Radiation Monitoring/methods , Water Quality , Water Pollutants, Radioactive/analysis , Humans , Research Design , Radiation Exposure/analysis
19.
RECIIS (Online) ; 18(2)abr.-jun. 2024.
Article in Portuguese | LILACS, Coleciona SUS | ID: biblio-1562603

ABSTRACT

O filme "Safe" (1995), dirigido por Todd Haynes, conta a história de Carol White, dona de casa de classe média alta em Los Angeles, que começa a sofrer de uma misteriosa alergia aos frutos da "modernidade" (alimentos ultraprocessados, produtos sintéticos e poluição). Realizado décadas atrás, o filme é atual para criticar a sociedade contemporânea, explorando a desconexão e o vazio existencial nas crises ambientais. A resenha se aprofunda nos dilemas sofridos pela personagem que, apesar de viver em um ambiente abastado, sente-se alienada e busca refúgio em um grupo que oferece uma solução pseudocientífica para seu mal. O filme se posiciona como uma crítica à sociedade de consumo e às consequências das políticas neoliberais, questionando a eficácia de soluções superficiais para problemas profundos e sistêmicos.


The film "Safe" (1995), directed by Todd Haynes, tells the story of Carol White, an upper-middle-class housewife in Los Angeles, who begins to suffer from a mysterious allergy to the fruits of "modernity" (ultra-processed foods, synthetic products and pollution). Despite being made decades ago, the film is current in criticizing contemporary society, exploring the disconnection and existential void in environmental crises. The review delves into the dilemmas suffered by the character who, despite living in a wealthy environment, feels alienated and seeks refuge in a group that offers a pseudoscientific solution to her illness. The film positions itself as a critique of consumer society and the consequences of neoliberal policies, questioning the effectiveness of superficial solutions to deep, systemic problems.


La película "Safe" (1995), dirigida por Todd Haynes, cuenta la historia de Carol White, una ama de casa de clase media alta de Los Ángeles, que comienza a sufrir una misteriosa alergia a los frutos de la "modernidad" (alimentos, productos ultraprocesados, productos sintéticos y contaminación). A pesar de haber sido realizada hace décadas, la película está vigente en su crítica a la sociedad contemporánea, explorando la desconexión y el vacío existencial en las crisis ambientales. La reseña profundiza en los dilemas que sufre el personaje que, pese a vivir en un entorno acomodado, se siente alienada y busca refugio en un grupo que ofrece una solución pseudocientífica a su enfermedad. La película se posiciona como una crítica a la sociedad de consumo y las consecuencias de las políticas neoliberales, cuestionando la efectividad de soluciones superficiales a problemas sistémicos profundos.


Subject(s)
Socioeconomic Factors , Mental Health , Risk Factors , Environment , Motion Pictures , Risk-Taking , Cultural Factors , Environmental Restoration and Remediation , Policy , Economic Factors
20.
Plant Physiol Biochem ; 213: 108795, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38878390

ABSTRACT

Microplastics and nanoplastics (MNPs), are minute particles resulting from plastic fragmentation, have raised concerns due to their widespread presence in the environment. This study investigates sources and distribution of MNPs and their impact on plants, elucidating the intricate mechanisms of toxicity. Through a comprehensive analysis, it reveals that these tiny plastic particles infiltrate plant tissues, disrupting vital physiological processes. Micro and nanoplastics impair root development, hinder water and nutrient uptake, photosynthesis, and induce oxidative stress and cyto-genotoxicity leading to stunted growth and diminished crop yields. Moreover, they interfere with plant-microbe interactions essential for nutrient cycling and soil health. The research also explores the translocation of these particles within plants, raising concerns about their potential entry into the food chain and subsequent human health risks. The study underscores the urgency of understanding MNPs toxicity on plants, emphasizing the need for innovative remediation strategies such as bioremediation by algae, fungi, bacteria, and plants and eco-friendly plastic alternatives. Addressing this issue is pivotal not only for environmental conservation but also for ensuring sustainable agriculture and global food security in the face of escalating plastic pollution.


Subject(s)
Microplastics , Plants , Microplastics/toxicity , Plants/metabolism , Plants/drug effects , Soil Pollutants/toxicity , Soil Pollutants/metabolism , Biodegradation, Environmental , Nanoparticles/toxicity , Environmental Restoration and Remediation/methods , Plastics/metabolism , Plastics/toxicity , Environmental Pollution
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