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Tetracyclines are broad-spectrum antibiotics used as human and veterinary ailments, anticancer and antiviral agents, and for treating inflammations including arthritis and the Huntington's disease. However, their inappropriate usage and disposal induce environmental pollution due to their persistency, hydrophilicity and limited volatility, requiring advanced remediation methods. Here, we review techniques for tetracycline removal, including adsorption, advanced oxidation and filtration. Materials to treat tetracycline pollution include aged microplastics, green materials, chemical compounds, sonocatalysts and membranes. Complete tetracycline removal is achieved by using membranes, sonocatalysis and composites. Green composites appear eco-friendly for wastewater treatment. Chemically-synthesized composites are mainly used in photocatalysis, oxidative and enzymatic degradation. [ABSTRACT FROM AUTHOR]

Several approaches have been proposed to improve oil-contaminated soil remediation. However, the role of zeolite, a safe, clean, economical, and environmentally friendly material, in removing crude oil (CO) from contaminated soils remains unclear. This paper addresses this gap with respect to CO-contaminated sands (COCS) and aims to assess zeolite's capability as a geo-environmentally adaptable material to mitigate the adverse impacts of oil pollution on sandy soils. The cyclic simple shear behavior and chemical analysis of coarse and fine-grain silicate sands are investigated and compared in response to CO contamination. Clean sand specimens were prepared with 60% relative density, whereas COCS specimens were prepared using a 6% crude oil contamination level. This study examines the impact of CO contamination and the use of an environmentally friendly stabilizer through simple shear tests (under static and cyclic conditions), consolidation experiments, and Fourier-transform infrared spectroscopy (FTIR). Optimal pollution adsorption was achieved by adding 6% zeolite to fine-grained sand, resulting in a 31.61% increase in the shear modulus index and an 18.70% increase in the friction angle index. Using 8% zeolite improved the shear modulus and friction angle indexes in coarse-grained sand by 21.69% and 11.83%, respectively. FTIR results showed a 45% and 59% enhancement in coarse and fine sands, respectively, indicating the positive role of zeolite in stabilizing COCS through pollutant adsorption. The superior performance of zeolite in fine-grained compared with coarse-grained sand is justified by its higher specific surface area and porous surface. [ABSTRACT FROM AUTHOR]

The regulation of peroxymonosulfate (PMS) activation by photo‐assisted heterogeneous catalysis is under in‐depth investigation with potential as a replaceable advanced oxidation process in water purification, yet it remains a significant challenge. Herein, we demonstrate a strategy to construct polyethylene glycol (PEG) well‐coupled dual‐defect VO−M–Co3O4@CNx S‐scheme heterojunction to degrade organic pollutants without aeration, which dramatically provides abundant active sites, excellent photo‐thermal property, and distinct charge transport pathway for PMS activation. The degradation rate of VO−M−Co3O4@CNx in anaerobic conditions shows a higher efficient rate (4.58 min−1 g−2) than in aerobic conditions (1.67 min−1 g−2). Experimental evidence reveals that VO−M−Co3O4@CNx promotes more rapid redox conversion of photoexcited electrons induced by defects with PMS under anaerobic conditions compared to aerobic conditions. Additionally, in situ experiments and DFT provide mechanistic insights into the regulation pathway of PMS activation via synergistic defect‐induced electron, revealing the competitive effect between O2 and PMS over VO−M−Co3O4@CNx during the reaction process. The continuous flow reactor and flow cytometry results demonstrated that the VO−M−Co3O4@CNx/PMS/Vis system has remarkably enhanced stability and purification capability for removing organic pollutants. This work provides valuable insights into regulating the heterologous catalysis oxidation process without aeration through the photoexcitation synergistic PMS activation. [ABSTRACT FROM AUTHOR]

ABSTRACT The Oryctes rhinoceros (Scarabaeidae: Coleoptera) is a common coleopteran insect in tropical and subtropical areas with many potential uses. Its larvae are commonly found in dead coconut trees and hay piles in the wild and are widely distributed in the northern hemisphere. This study investigates the environmental factors influencing the growth of Oryctes rhinoceros beetle larvae and provides valuable insights into their breeding conditions versus their potential applications. The research examined three key affecting factors of larval development over time, namely, moisture content, growth space and soil content. Results of a pretest run revealed that moisture content, but not the soil content, affected the larval survival greatly. A reasonable confinement on feed moisture (i.e., 30%–60%) was included in the later conducted three‐factor factorial experiment. At last, results of the factorial run suggested that: (1) for a consistent and massive larval breeding, environmental factors, setting moisture content at 60%, larval space at 100 cm3/larva and no soil addition, are deemed appropriate, (2) for nutritional purpose, setting moisture content at 60%, larval space at 300 cm3/larva and no soil addition are recommended, and (3) for soil pollution remediation, setting moisture content at 60%, larval space at 100 cm3/larva and a soil‐to‐feed (S/F) ratio of 2:1 is concluded. This study marks the first engineering breeding exploration of Oryctes rhinoceros larvae, offering practical recommendations for various research purposes and applications. [ABSTRACT FROM AUTHOR]

Nitrogen (N) plays an important role in plant growth and developmental metabolic processes, research on nitrogen speciation regulating Cd accumulation in duckweed is still limited. In this study, the effects of three nitrogen sources (NH4Cl, Ca(NO3)2 and NH4NO3) on the growth, Cd accumulation, and photosynthetic parameters of Landoltia punctata (L.punctata) were analyzed. The results showed that Cd enrichment in L. punctata was significantly reduced (p < 0.05) with different nitrogen treatments compared to the control (CK). Ammonium nitrogen (NH4–N) is more conducive to the accumulation of Cd in L. punctata than nitrate nitrogen (NO3–N). The sum of the cell wall components and soluble components of Cd in the NH4–N treatment group was greater than that in the NO3–N treatment group. The proportion of FNaCl extracts in the NH4–N treatment group was greater than in the NO3–N treatment group. NO3–N led to a greater reduction in photosynthetic pigment content than NH4–N. Overall, applying different forms of nitrogen can alleviate Cd toxicity in L. punctata, and the detoxification effect of the NH4–N treatment is stronger than that of NO3–N treatment. This study will provide theoretical and practical support for the application of duckweed in Cd phytoremediation even in eutrophic aquatic environments. NOVELTY STATEMENT: Cd pollution has become a major global public environmental issue. Duckweed is an ideal species to restore Cd-polluted waters due to its fast growth, easy harvesting and hyperaccumulation Cd. Currently, no definite conclusion has been given on the detoxification effect of nitrogen morphology regulating the accumulation of Cd in plant. In this study, the influence of different nitrogen forms on Cd-induced toxicity in Landoltia punctata were revealed through the changes in biomass, Cd subcellular distribution, Cd chemical morphology and photosynthetic pigment. These findings can provide a new way of analyzing the mechanism of Cd enrichment in plants, and also provide theoretical and technical support for the remediation of Cd pollution by using duckweed resources. The Cd-accumulation duckweed can be pyrolyzed to produce biochar, which can not only control the second pollution by decomposed plant bodies but also realizes the efficient use of waste. HIGHLIGHTS: Nitrogen reduced the Cd accumulation in Landoltia punctata due to increased plant biomass. Nitrogen can alter the subcellular distribution and chemical forms of Cd in Landoltia punctata. NH4-N enhanced Cd tolerance of duckweed compared to NO3-N. Lower mobilization of Cd and cell wall combination are the main detoxification strategies for NH4-N supply. [ABSTRACT FROM AUTHOR]

Metal(loid) pollutants in road dust (road-deposited sediment) show obvious seasonal characteristics under the influence of sources. However, the short-term (days to weeks) variations of metal contamination in road dust in different functional areas with antecedent dry days (ADDs) and their relationships with the source factors were poorly understood, which reduced the comparability of researches and effectiveness of pollution remediation. Herein, temporal characteristics of As, Ba, Ca, Cd, Cr, Cu, Pb and Zn contamination in road dust were studied in two distinct functional areas in Nanjing, i.e. an urban park (Xuanwu, XW) and a stop light-controlled traffic intersection (Baima, BM), following a continuous 23-day sampling between two rainfall events. Mean concentrations of each metal at BM and XW were 1.6–29.5 and 1.3–10.8 times higher than those in the background soil, respectively. The enrichment factor (EF) was used to compensate for grain-size effect. EFs of metals were between 1.3 and 50.3, showing minor to extremely high contamination and different temporal trends. Combined with the EFs and positive matrix factorization (PMF) results, dry atmospheric deposition of industrial and construction sources was the main cause for comparable contamination levels of As, Ca, Cd and Zn between BM and XW and those stable temporal trends. Due to the traffic contribution, contamination levels of Cu, Ba, Pb and Cr at BM were higher (p <.05) than at XW. Different from the stable contamination levels at XW, contamination levels of Cu, Ba, Pb and Cr decreased at BM with the ADDs due to the dilution of traffic particles by less metal enriched atmospheric deposition. These results shed light on the quite different variations of metal contamination in road dust from different functional areas with ADDs under the influence sources, and have instructive significance on road dust sampling, metal contamination remediation and comparison between studies. [ABSTRACT FROM AUTHOR]

Soil contamination by heavy metals poses serious risks to human health due to their high toxicity and resistance to biodegradation, especially when they accumulate through the food chain. Soil drenching technology is one of the most promising methods for soil pollution remediation. In this research, microbubbles were introduced into the disodium ethylenediamine tetraacetate(EDTA-2Na) solution during soil drenching, combined with Polysorbate 80(TW-80) to remove heavy metals(Cu, Cd) from the soil. The microbubbles contributed to concentrating heavy metals, thus lowering their levels in the solution. The efficiency of heavy metal removal was found to be positively correlated with both time and detergent concentration, and negatively correlated with pH levels. Under conditions where the washing time was 120 minutes, EDTA-2Na concentration was 1 g/L, TW-80 concentration was 2 g/L, the solid-liquid ratio was 1:30, the gas-liquid ratio was 1:3, and the pH was maintained at 3, the removal rates for Cu and Cd were 86.67% and 85.52%, respectively. The Community Bureau of Reference (BCR) sequential extraction procedure revealed that intensive was Ahile et al., 2021 hing with microbubbles effectively eliminated acid-soluble (F1) and reducible (F2) heavy metals from the soil, thereby mitigating their detrimental effects on soil ecosystems. These insights offer a theoretical and practical foundation for employing microbubble technology in the remediation of heavy metal ion pollution in soils. [ABSTRACT FROM AUTHOR]

The accumulation of cadmium (Cd) in facility soil is attracting increasing attention. Reductive soil disinfestation (RSD) is an effective soil disinfectionmethod, while also having a certain passivating effect on Cd. The application of organic matter is crucial for the success of RSD, but the reduction efficiencies of different organic materials vary. Here, five treatments, namely untreated soil (CK), bean dregs (BD), peanut dregs (PD), sesame dregs (SD), and apple dregs (AD) were applied, and their performances in Cd immobilization in Cd-contaminated soil were assessed. Changes in soil properties and microbial communities were monitored. The results showed that the overall soil pH following RSD treatment decreased significantly, while organic matter, hydrolyzed nitrogen, available phosphorus, available potassium, exchangeable calcium, and exchangeable magnesium increased significantly. Compared to CK, the exchangeable (EX)-Cd contents after treatments SD and AD significantly decreased by 25.4% and 23.7%, respectively. RSD led to significant changes in the composition of soil microbial communities. SD treatment significantly increased the number of soil fungal operational taxonomic units (OTU), while BD, PD, and SD significantly increased the relative abundances of Bacteroidetes, Chloroflexi, Deinococus Thermus, and Basidiomycota in bacterial communities. The Gemmatimonadetes phylumshowed a highly significant negative correlation with EX-Cd, indicating that it might have a positive effect on the fixation of Cd in polluted soil. SD significantly reduced the Cd content in the above-ground parts of lettuce by 74.76%, and had the least impact on lettuce biomass. It can be inferred that RSD is an ecologically effective method for the remediation of Cd pollution in facility soil by improving soil characteristics and altering microbial community composition to reduce Cd activity. However, further in-depth research is needed to optimize the types and amounts of organic materials applied. [ABSTRACT FROM AUTHOR]

Amongst the many types of food waste, eggshells contain various minerals and bioactive materials, and they can become hazardous if not properly disposed of. However, they can be made useful for the environment and people by being converted to environmentally friendly catalytic materials or environmental purification agents. Simple calcination can enhance their properties and thereby render them suitable for catalytic and environmental applications. This work aimed to prepare CaO from waste eggshells and examine its effectiveness in photocatalytic pollution remediation, electrocatalytic activity, optical sensing, and antibacterial activities. As opposed to other techniques, this calcination process does not require any chemical reagents due to the high purity of CaCO3 in eggshells. Calcium oxide nanoparticles were prepared by subjecting waste eggshells (ES) to high-temperature calcination, and the synthesized CaO nanoparticles were characterized for their structural, morphological, chemical, optical, and other properties. Furthermore, their photocatalytic degradation of methylene blue dye and antibacterial efficiency against Escherichia coli and Staphylococcus aureus were investigated. It was found that the green-converted CaO can be efficiently used in environmental applications, showing good catalytic properties. [ABSTRACT FROM AUTHOR]

Selecting representative groundwater monitoring wells in polluted areas is crucial to comprehensively assess groundwater pollution, thereby ensuring effective groundwater remediation. However, numerous factors can affect the effectiveness of groundwater monitoring well network optimizations. A local sensitivity analysis method was used in this study to analyze the hydrogeological parameters of a simulation groundwater solute transport model. The results showed a strong effect of longitudinal dispersion and transverse dispersion on the output results of the simulation model, and a good fit between the backpropagation neural network (BPNN)-based alternative model's results and those obtained using the solute transport simulation model, accurately reflecting the input and output relationship of the simulation model. The optimized groundwater monitoring layout scheme consisted of four groundwater monitoring wells, namely no. 7, no. 16, no. 23, and no. 24. These wells resulted in a groundwater fluoride pollution rate of 98.44%, which was substantially higher than that obtained using the random layout scheme. In addition, statistical analysis of the fluoride groundwater pollution results obtained using the Monte Carlo random simulation highlighted continuous and high groundwater fluoride levels in the second and third pollution sources and their downstream groundwater. Therefore, more attention should be devoted to these sources to ensure the effective remediation of groundwater pollution in the study area. [ABSTRACT FROM AUTHOR]

Small-scale robots with shape anisotropy have garnered significant scientific interest due to their enhanced mobility and precise control in recent years. Traditionally, these miniature robots are manufactured using established techniques such as molding, 3D printing, and microfabrication. However, the advent of microfluidics in recent years has emerged as a promising manufacturing technology, capitalizing on the precise and dynamic manipulation of fluids at the microscale to fabricate various complex-shaped anisotropic particles. This offers a versatile and controlled platform, enabling the efficient fabrication of small-scale robots with tailored morphologies and advanced functionalities from the microfluidic-derived anisotropic microparticles at high throughput. This review highlights the recent advances in the microfluidic fabrication of anisotropic microparticles and their potential applications in small-scale robots. In this review, the term 'small-scale robots' broadly encompasses micromotors endowed with capabilities for locomotion and manipulation. Firstly, the fundamental strategies for liquid template formation and the methodologies for generating anisotropic microparticles within the microfluidic system are briefly introduced. Subsequently, the functionality of shape-anisotropic particles in forming components for small-scale robots and actuation mechanisms are emphasized. Attention is then directed towards the diverse applications of these microparticle-derived microrobots in a variety of fields, including pollution remediation, cell microcarriers, drug delivery, and biofilm eradication. Finally, we discuss future directions for the fabrication and development of miniature robots from microfluidics, shedding light on the evolving landscape of this field. [ABSTRACT FROM AUTHOR]

As an energy-saving and facile technology, electrosorption technology has good potential in the process of separation of uranium from aqueous solution. In this study, sucrose and urea were used to prepare nitrogen-doped carbon by one-step carbonization, and polyacrylamide modified nitrogen doped carbon (PAM/NC) was obtained by modification. The electrosorption test results indicated that PAM/NC-2 had the best properties and the maximum electrosorption capacity was 619.5 mg g−1. The performance loss was less than 20% after 5 adsorption–desorption cycles. Overall, this material had a potential application in U(VI) pollution remediation, meeting the need for sustainable development of nuclear energy. [ABSTRACT FROM AUTHOR]

Aquaculture and the production of aquatic goods are rapidly growing industries in the world. These industries involve the cultivation of various saltwater and freshwater fish as well as shellfish species, and they undergo regular updates in their manufacturing processes. The increasing popularity of aquaculture is driven by the desire to achieve long-term sustainability in food production. However, the intensification of farming techniques can lead to economic losses due to fish mortality, which is often caused by infectious and stressful conditions. To address this challenge, it is crucial to enhance the immune response of fish as part of sustainable intensification and aquaculture management. Recently, there has been growing interest in eco-friendly and natural bioactive solutions as potential alternatives to synthetic compounds used for disease prevention in aquaculture. Medicinal plants, available as whole plants, plant extracts, or synthetic analogues of natural substances known as phytomedicines or phytopharmaceuticals, have shown high efficacy in disease prevention for humans and animals. One such medicinal plant is Saussurea lappa, which is extensively utilized in various forms of medicine for treating multiple diseases. The bioactive chemicals derived from S. lappa exhibit a wide range of biological activities, including anti-inflammatory, antioxidant, antimicrobial, and anticancer properties, along with immunostimulatory effects. Given the diverse biological activities of S. lappa and its potential to enhance the immune responses of aquatic species, this review focuses on exploring its contributions in this area. By examining the numerous benefits and applications of S. lappa, we aim to shed light on its potential role in improving the immune response of aquatic species. [ABSTRACT FROM AUTHOR]

The eco-toxicological effects of industrial wastewater in different parts of the global ecosystem have been a prominent matter of concern over the last 20 years. To mitigate these effects, industrial wastewater should be pollutant-free, and as a result, different technologies, including conventional and non-conventional, have been introduced so far. Due to these technologies, conventional treatment technologies are uneconomical due to the high energy demand for removing industrial wastewater pollutants. So, with advancements in technology, non-conventional technologies, including bio-electrochemical systems (BES), have been introduced and have proven environmentally sustainable. BES combines biology and electrochemistry to produce bioenergy and degrade pollutants from industrial wastewater. BES consumes energy in the chemical bonds of industrial wastes to efficiently degrade the contaminants. Apart from that, BES faces some major challenges, including high capital costs and scalability. BES scale-up challenges include electrode conductivity, sub-optimal contact, and high internal resistance between electrodes. The global demand for microbial fuel cells (MFC) was $8.60 million in 2017 and grew at a compound yearly growth rate of 11.2%, with a projected increase to $22.38 million by 2026. Thus, this review focuses on the pollutant release mechanisms of different industries that cause eco-toxicity threats to human health and water bodies. In addition, this study extensively discussed the pollution remediation by BES and factors affecting BES-based remediation. [ABSTRACT FROM AUTHOR]

This study synthesized a ferric oxide–nanographite (NG) nanocomposite (Fe2O3@NG) from waste toner powder through carbonization. Subsequently, a TiO2/Fe2O3@NG nanohybrid was fabricated using the sol–gel technique to improve the photocatalytic degradation of dyes. TiO2/Fe2O3@NG nanocomposites were prepared at TiO2:Fe2O3@NG ratios of 2:1 (Ti:T-21), 1:1 (Ti:T-11), and 1:2 (Ti:T-12). The porosity, morphology, surface chemistry, and chemical interactions between TiO2, Fe2O3, and graphite in the prepared TiO2/Fe2O3@NG nanocomposites were characterized using the Brunauer–Emmett–Teller (BET) method and microscopic and spectroscopic analyses. The TiO2/Fe2O3@NG nanohybrid exhibited a reduced bandgap (2.4–2.9 eV) and enhanced charge carrier separation through charge transfer at the junction of the hetero-structured TiO2/Fe2O3@NG nanohybrid. Preliminary experiments revealed that Ti:T-21 was the most effective photocatalyst for degrading acid blue-25 (AB-25) compared to Ti:T-11, Ti:T-12, sole TiO2, and Fe2O3@NG. This study also investigated the impacts of catalyst dose and initial dye concentration on the AB-25 photocatalytic degradation. Notably, 97% of 5-mg/L AB-25 was removed using 1.25-g/L Ti:T-21 at an unmodified pH of 6.4 within 120 min. Furthermore, Ti:T-21 exhibited remarkable recyclability in its immobilized form, achieving degradation ratios of 74.7%–71.8% over five consecutive runs, compared to removal efficiencies of 85.0%–62.3% in the suspended mode. Trapping experiments identified hydroxyl radicals, holes, and superoxide as the principal reactive radicals. The TiO2/Fe2O3@NG/light system was effective in disintegrating and mineralizing other synthetic dyes such as Congo red, methylene blue, and methyl red, indicating its potential for industrial-scale degradation of authentic dye wastewater. The utilization of waste toner for water treatment is highlighted as a strategy to promote environmental sustainability, foster a circular economy, and contribute to pollution remediation.

Abstract Present study assessed the growth of two plant species and ion uptake by them grown on different proportion of industrial solid waste and garden soil. The industrial waste having high concentration of chemicals were used with garden soil at different proportion i.e. 0% (T0), 5% (T1), 10% (T2), 15% (T3) and 20% (T4). Two species namely Conocarpus erectus (alien plant) and Dodonaea viscosa (indigenous) were used as test plants in pot study. Different parameters including growth, physiology, and anatomy of plants and concentration of cations (Na+, K+, Ca2+, and Mg2+) in the plant shoot and root were measured at different time duration (initial, 1st, 2nd, 3rd and 4th month). The key objective of the study was to use these plants to establish their plantations on the barren lands where industrial solid wastes were being disposed of. C. erectus showed better growth than D. viscosa, as well as more uptake of ions. A significant increase in plant growth was observed in fourth month in T1, where plant height reached 24.5% and 46% for C. erectus and D. viscosa, respectively. At harvest, in C. erectus, no significant difference in the fresh (65–78 g) and dry weight (24–30 g) of the shoot was observed across treatments compared to the control. In D. viscosa, at the time of harvest, the fresh and dry weights of the root and shoot showed a strong, significantly decreasing pattern across T1, T2, and T3, leading to the death of the plant at T3 and T4. Further, optimum ratio of waste soil to garden soil was found as 10:90 and 20:80 to establish the plantations of D. viscosa and C. erectus, respectively in areas where such solid waste from industries are disposed. Findings can be used for the restoration of such solid waste for the sustainable management of industrial areas and their associated ecosystems.

Geopolymers derived from solid waste can effectively remediate heavy metal polluted sites, achieving the ideal fusion of solid waste utilization and environmental remediation. Red mud and blast furnace slag were used to develop a geopolymer for the remediation of composite heavy metal-contaminated soils, focusing on Cd(II)-, Pb(II)-, Cu(II)-, and Zn(II)-contaminated soils. Uniaxial compressive strength tests, toxicity characteristic leaching procedures, pH change characteristics, and pH gradient tests were performed on the solidified/stabilized soil. The results showed that increasing the red mud-blast furnace slag content and curing age significantly enhanced the unconfined compressive strength. Furthermore, it suppressed the leaching of heavy metals in the solidified/stabilized soil. Notably, the treatment effectiveness of Cu(II) and Zn(II) was superior to that of Cd(II) and Pb(II). The leaching concentrations of Cd(II), Pb(II), and Zn(II) decreased in acidic to weakly alkaline environments but increased in strongly alkaline environments. However, the impact of curing age and initial heavy metal content on the pH of the solidified/stabilized soil was the opposite. In conclusion, red mud and blast furnace slag exhibited superior solidification/stabilization effects compared to cement. As environmental protection awareness grows and technology continues to evolve, geopolymers derived from red mud and blast furnace slag will play a greater role in pollution control and remediation, showcasing broad application prospects. [ABSTRACT FROM AUTHOR]

This study contains a mathematical model for river pollution and its remediation for an unsteady state and investigates the effect of aeration on the degradation of pollutants. The governing equation is a pair of nonlinear time-fractional two-dimensional advection-diffusion equations for pollutant and dissolved oxygen (DO) concentration. The coupling of these equations arises due to the chemical interactions between oxygen and pollutants, forming harmless chemicals. The Fractional Reduced Differential Transform Method (FRDTM) is applied to provide approximate solutions for the given model. Also, the convergence of solutions is checked for efficacy and accuracy. The effect of longitudinal and transverse diffusion coefficients of pollutant and DO on the concentration of pollutant and DO is analyzed numerically and graphically. Also, we checked the effect of change in the river's longitudinal and transverse seepage velocity on pollutant and DO concentration numerically and graphically. We analyzed the comparison of change in the value of half-saturated oxygen demand concentration for pollutant decay on pollutant and DO concentration numerically and graphically. Also, numerical and graphical analysis examined the effect of fractional parameters on pollution levels. [ABSTRACT FROM AUTHOR]

Soil heavy metal pollution presents a significant environmental challenge globally, with cadmium (Cd) pollution being highly severe and posing risks to both soil ecological security and human health. Biochar offers advantages such as reduced costs, stable chemical properties, a micro-porous structure, and an expansive, specific surface area that aids in the fixation of heavy metals in soil. However, there has been little research on the adsorption mechanism of sulfur-modified biochar. Indigenous woody peat (BC) was used as a biochar substrate to evaluate the immobilization effectiveness of sulfur-modified woody peat (SBC) in Cd-contaminated soil in terms of cadmium and to determine the adsorption mechanism. Electron microscopy (SEM) and energy dispersive spectroscopy (EDS) showed that the S element was loaded on the surface of woody peat materials. X-ray photoelectron spectroscopy (XPS) analysis indicated that Cd in woody peat biochar is adsorbed mainly through the formation of Cd(OH)2 and CdCO3 precipitates. Additionally, SBC facilitated the interaction between Cd and organic sulfur, leading to the formation of more stable CdS and CdHS+ that were not easily dissolved or oxidized. The study also examined the adsorption mechanism. The results indicated that the material adhered to the second-order kinetic adsorption model. SBC had a greater capacity than BC to adsorb Cd, approximately six times greater. The soil culture experiment yielded varying effects with the addition of SBC and BC, notably on the soil pH and available Cd content. Adding 1% SBC resulted in a 12.5% increase in soil pH to a level of 7.52. After a 1% SBC treatment, the availability of Cd in the soil reduced significantly, with only 4.01 mg/kg found, which was significantly different from the control (CK) treatment (P < 0.05). These results suggest that SBC has promising potential for pollutant remediation applications. [ABSTRACT FROM AUTHOR]

As the energy demand increases, there is a significant expansion and utilization of oil resources, resulting in the inevitable occurrence of environmental pollution. Oil has been identified as a prevalent soil contaminant, posing substantial risks to the soil ecosystems. The remediation of soil contaminated with oil is a formidable undertaking. Increasing evidence shows that chemical washing, a remediation technique employing chemical reagents like surfactants to augment the solubilization, desorption, and separation of petroleum hydrocarbons in soil, proves to be an efficacious approach, but the latest advances on this topic have not been systematically reviewed. Here, we present the state of knowledge about the surfactant-based chemical washing to remediate oil-contaminated soil. Using the latest data, the present article systematically summarizes the advancements on ex situ chemical washing of oil pollution and provides a concise summary of the underlying principles. The use of various surfactants in chemical washing and the factors influencing remediation efficiency are highlighted. Based on the current research status and knowledge gaps, future perspectives are proposed to facilitate chemical washing of oil-polluted soil. This review can help recognize the application of chemical washing in the remediation of oil-polluted soil. [ABSTRACT FROM AUTHOR]

Water pollution is a pressing global concern, with per- and polyfluoroalkyl substances (PFAS) being considered as "forever contaminants." Among them, perfluorooctanesulfonic acid (PFOS) has received significant attention for its adverse effects on human health and aquatic ecosystems. This study aimed to design an innovative adsorbent for effective PFOS removal with exceptional water stability, improving its cost-performance trade-off. The current work simultaneously improved the stability of water of Cu-based metal–organic framework (CMOF) and increased its PFOS removal capacity by modifying it with amine-functionalized SiO2 nanoparticles (AF-CMOF). AF-CMOF presented a lower specific surface area of 999 m2 g−1 compared to CMOF with a surface area of 1098 m2 g−1. AF-CMOF showed remarkable PFOS uptake performance of 670 mg/g compared to the performance of the Cu-based MOF which exhibited a PFOS uptake capacity of only 22 mg/g. The most suitable pH for PFOS removal using both adsorbents was determined to be 3. In addition, AF-CMOF demonstrated excellent water stability, retaining its structural integrity even after seven days of water contact, while CMOF structure collapsed rapidly after four days of water exposure. Moreover, the study identified the significant pH influence on the PFOS uptake process, with electrostatic interactions between protonated amine functionalities and PFOS molecules identified as the dominant mechanism. The study's findings present the potential of synthesized adsorbent as a superior candidate for PFOS uptake and contribute to the development of effective water treatment technologies. [ABSTRACT FROM AUTHOR]

Microalgae represent an alternative to conventional wastewater treatment, potentially improving antibiotic removal and offering a solution to combat the spread of antimicrobial resistance. Through batch assays, this study investigates the routes for antibiotic removal using three strains (Chlamydomonas acidophila, Auxhenochlorella protothecoides and Tetradesmus obliquus). Using mixtures of ciprofloxacin, clarithromycin, erythromycin, metronidazole, ofloxacin, sulfamethoxazole, and trimethoprim at concentrations simulating wastewater composition, it also assesses antibiotic effects on microalgae physiology. The three strains primarily removed antibiotics through rapid biosorption, achieving up to 91.5% removal for specific ones like ciprofloxacin. T. obliquus and C. acidophila showed efficacy, with total removals of 37.2% and 49.3%, respectively. Over time, A. protothecoides demonstrated the highest active removal efficiency, eliminating 22.1% of total antibiotics, with a notable 67.6% removal for sulfamethoxazole. Abiotic degradation through hydrolysis and photolysis contributed to ciprofloxacin, ofloxacin, clarithromycin, and erythromycin removal (34.7% to 96.7%), showing pH-dependent photolysis. However, algae induced a shading effect, reducing the photolytic and hydrolytic degradation of specific antibiotics. T. obliquus and C. acidophila were inhibited by antibiotics, whereas A. protothecoides showed a 30.6% growth rate increase. The stimulatory effect was also observed for the nutrient removal, with A. protothecoides showing a 46.6% increase in ammonium removal and a 44.8% increase in phosphate removal with antibiotics. Additionally, antioxidant activities remained stable, except for a notable increase in peroxidase activity for A. protothecoides and T. obliquus. The study confirms efficient antibiotic removal and stimulatory responses in the three algal strains, indicating their potential for wastewater treatment and combating antimicrobial resistance. [ABSTRACT FROM AUTHOR]

Mercury is a global pollutant that poses significant risks to human health and the environment. Natural sources of mercury include volcanic eruptions, while anthropogenic sources include industrial processes, artisanal and small-scale gold mining, and fossil fuel combustion. Contamination can arise through various pathways, such as atmospheric deposition, water and soil contamination, bioaccumulation, and biomagnification in food chains. Various remediation strategies, including phytoremediation, bioremediation, chemical oxidation/reduction, and adsorption, have been developed to address mercury pollution, including physical, chemical, and biological approaches. The effectiveness of remediation techniques depends on the nature and extent of contamination and site-specific conditions. This review discusses the challenges associated with mercury pollution and remediation, including the need for effective monitoring and management strategies. Overall, this review offers a comprehensive understanding of mercury contamination and the range of remediation techniques available to mitigate its adverse impacts. [ABSTRACT FROM AUTHOR]

The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) has been widely used around the world in both agricultural and non-agricultural fields due to its high activity. However, the heavy use of 2,4-D has resulted in serious environmental contamination, posing a significant risk to non-target organisms, including human beings. This has raised substantial concerns regarding its impact. In addition to agricultural use, accidental spills of 2,4-D can pose serious threats to human health and the ecosystem, emphasizing the importance of prompt pollution remediation. A variety of technologies have been developed to remove 2,4-D residues from the environment, such as incineration, adsorption, ozonation, photodegradation, the photo-Fenton process, and microbial degradation. Compared with traditional physical and chemical remediation methods, microorganisms are the most effective way to remediate 2,4-D pollution because of their rich species, wide distribution, and diverse metabolic pathways. Numerous studies demonstrate that the degradation of 2,4-D in the environment is primarily driven by enzymatic processes carried out by soil microorganisms. To date, a number of bacterial and fungal strains associated with 2,4-D biodegradation have been isolated, such as Sphingomonas, Pseudomonas, Cupriavidus, Achromobacter, Ochrobactrum, Mortierella, and Umbelopsis. Moreover, several key enzymes and genes responsible for 2,4-D biodegradation are also being identified. However, further in-depth research based on multi-omics is needed to elaborate their role in the evolution of novel catabolic pathways and the microbial degradation of 2,4-D. Here, this review provides a comprehensive analysis of recent progress on elucidating the degradation mechanisms of the herbicide 2,4-D, including the microbial strains responsible for its degradation, the enzymes participating in its degradation, and the associated genetic components. Furthermore, it explores the complex biochemical pathways and molecular mechanisms involved in the biodegradation of 2,4-D. In addition, molecular docking techniques are employed to identify crucial amino acids within an alpha-ketoglutarate-dependent 2,4-D dioxygenase that interacts with 2,4-D, thereby offering valuable insights that can inform the development of effective strategies for the biological remediation of this herbicide. [ABSTRACT FROM AUTHOR]

Present study assessed the growth of two plant species and ion uptake by them grown on different proportion of industrial solid waste and garden soil. The industrial waste having high concentration of chemicals were used with garden soil at different proportion i.e. 0% (T0), 5% (T1), 10% (T2), 15% (T3) and 20% (T4). Two species namely Conocarpus erectus (alien plant) and Dodonaea viscosa (indigenous) were used as test plants in pot study. Different parameters including growth, physiology, and anatomy of plants and concentration of cations (Na+, K+, Ca2+, and Mg2+) in the plant shoot and root were measured at different time duration (initial, 1st, 2nd, 3rd and 4th month). The key objective of the study was to use these plants to establish their plantations on the barren lands where industrial solid wastes were being disposed of. C. erectus showed better growth than D. viscosa, as well as more uptake of ions. A significant increase in plant growth was observed in fourth month in T1, where plant height reached 24.5% and 46% for C. erectus and D. viscosa, respectively. At harvest, in C. erectus, no significant difference in the fresh (65–78 g) and dry weight (24–30 g) of the shoot was observed across treatments compared to the control. In D. viscosa, at the time of harvest, the fresh and dry weights of the root and shoot showed a strong, significantly decreasing pattern across T1, T2, and T3, leading to the death of the plant at T3 and T4. Further, optimum ratio of waste soil to garden soil was found as 10:90 and 20:80 to establish the plantations of D. viscosa and C. erectus, respectively in areas where such solid waste from industries are disposed. Findings can be used for the restoration of such solid waste for the sustainable management of industrial areas and their associated ecosystems. [ABSTRACT FROM AUTHOR]

Despite the major influence of soils on climate change, carbon sequestration, pollution remediation, and food security, soil remains a largely unexplored media with an extreme complexity of microbes, minerals, and dead organic matter, most of them being actually poorly known. In particular, soil biofilms have recently attracted attention because they strongly influence biogeochemical reactions and processes. Here we review biofilms with focus on their behavior, proliferation, distribution, characterization methods, and applications. Characterization methods include optical, electron, scanning probe, and X-ray microscopy; metagenomics, metatranscriptomics, metaproteomics, metabolomics; and tracking approaches. Applications comprise pollution remediation by metal immobilization or organics degradation; and methane oxidation, carbon dioxide reduction, and carbon sequestration. Advanced methods such as DNA-stable isotope probing and meta-omics have uncovered the multiple functions of soil biofilms and their underlying molecular mechanisms. Investigations have improved our understanding of inter- and intra-kingdom interactions, and of gene transfer. Extracellular materials such as polysaccharides enhance the transport of substances and electrons flow among microorganisms. [ABSTRACT FROM AUTHOR]

The widespread and excessive occurrence of uranium causes serious environmental risks. This review presents several important analytical methods for determining elemental and isotopic levels of uranium in samples, involving inductively coupled plasma mass spectrometry (ICP-MS), Raman spectroscopy, LED fluorimetry, multi-collector ICP-MS (MC-ICP-MS) and high-resolution ICP-MS (HR-ICP-MS). Furthermore, the methods and application of microbial remediation and phytoremediation in uranium contaminated soil are summarised in this review. A comprehensive discussion is also provided on several mitigation techniques that effectively used to remove uranium from water. These remediation techniques include a variety of biochars, nanotechnology and removal using magnesium-iron based hydrotalcite- like complexes. [ABSTRACT FROM AUTHOR]

Heavy metal composite pollution, such as Cd–Pb, occurs commonly in agriculture soils around the world, potentially harming the ecological environment and human health via food chain/network migration. There are numerous strategies for treating and rehabilitating polluted farmland today, including the use of attractive plants for phytoremediation. However, it is unclear how to use attractive plants to properly treat and fully utilize Cd–Pb composite damaged farms. The combined Cd–Pb pollution of agriculture in Xieping village, Huixian county, Gansu province is increasingly prevalent. Therefore, based on the results of literature research and the actual situation of the study area, nine kinds of ornamental plants with Cd–Pb composite pollution remediation potential and comprehensive utilization value were first selected in this paper, and the greenhouse test was carried out in the Cd–Pb composite pollution farmland in the study area. Second, the bioconcentration factor (BCF), transfer coefficient (TF), and economic feasibility principle were utilized to select the best treatment plants, and a novel model of effective remediation and comprehensive exploitation of Cd–Pb composite damaged farmland was developed. The results showed that the nine tested plants grew well under the Cd–Pb combined pollution stress, and all of them showed certain tolerance. However, the biomass, Cd–Pb accumulation, enrichment and transport capacity of the different plants were significantly different. Among them, Paeonia suffruticosa Andr., Rumex acetosa L., Calendula officinalis L., Rose chinensis Jacq., Tagetes erecta L. and Impatiens balsamina L. show excellent restorative abilities. Combining the ornamental value, safety and economy of flowering plants, P. suffruticosa, R. chinensis, C. officinalis, T. erecta and I. balsamina were finally selected as the plants for the effective remediation and comprehensive utilisation of Cd–Pb composite pollution in farmland. In conclusion, this study proposes a new model for the effective remediation and comprehensive utilisation of heavy metal composite pollution in farmland by flowering plants with economic feasibility. [ABSTRACT FROM AUTHOR]

In this study, we used 16S high-throughput sequencing to investigate the effects of uranium mining on the rhizospheric bacterial communities and functions of three local plant species, namely, Artemisia frigida, Acorus tatarionwii Schott., and Salix oritrepha Schneid. The results showed that uranium mining significantly reduced the diversity of rhizospheric bacteria in the three local plant species, including the Shannon index and Simpson index (P < 0.05). Interestingly, we found that Sphingomonas and Pseudotrichobacter were enriched in the rhizosphere soil of the three local plants from uranium mining areas, indicating their important ecological role. The three plants were enriched in various dominant rhizospheric bacterial populations in the uranium mining area, including Vicinamidobacteriaceae, Nocardioides, and Gaiella, which may be related to the unique microecological environment of the plant rhizosphere. The rhizospheric bacterial community of A. tatarionwii plants from tailings and open-pit mines also showed a certain degree of differentiation, indicating that uranium mining is the main factor driving the differentiation of plant rhizosphere soil communities on the plateau. Functional prediction revealed that rhizospheric bacteria from different plants have developed different functions to cope with stress caused by uranium mining activities, including enhancing the translational antagonist Rof, the translation initiation factor 2B subunit, etc. This study explores for the first time the impact of plateau uranium mining activities on the rhizosphere microecology of local plants, promoting the establishment of effective soil microecological health monitoring indicators, and providing a reference for further soil pollution remediation in plateau uranium mining areas. [ABSTRACT FROM AUTHOR]

A novel polymer synthesized by grafting three cyclodextrins onto chitosan was characterized and evaluated for its potential to adsorb two pharmaceutical residues: ibuprofen and progesterone. The influence of various operational parameters, including contact time, initial molecule concentration, pH, ionic strength, and temperature, was investigated. The synthesized polymer exhibits an amorphous and porous structure with a remarkable swelling capacity of 9.5 mmol/g. It demonstrates remarkable adsorption capacities for progesterone and ibuprofen, reaching 90% and 75%, respectively. Kinetic studies reveal that the adsorption of both molecules follows a pseudo-second-order model. A DSC analysis elucidated the adsorption mechanism, which is governed by the formation of inclusion complexes and electrostatic interactions within the polymer network. The polymer's regeneration after 23 cycles demonstrates its sustainable adsorption efficiency. The combination of chitosan with three cyclodextrins opens up promising new avenues for water treatment and the removal of specific pollutants. This approach significantly improves the material's selectivity towards target pollutants, offering a significant advantage in pollution remediation applications. [ABSTRACT FROM AUTHOR]

Research on the migration behaviors of contaminants in the aquitard has been deficient for an extended period. Clay is commonly employed as an impermeable layer or barrier to stop the migration of contaminants. However, under certain conditions, the clay layer may exhibit permeability to water, thereby allowing contaminants to infiltrate and potentially contaminate adjacent aquifers. Consequently, it holds immense importance to scrutinize and investigate the migration characteristics of light non-aqueous phase liquid (LNAPL) within the aquitard for the purposes of groundwater pollution control and remediation. To evaluate the environmental risk posed by organic contaminants in the aquitard, an experimental model was formulated and devised to monitor the LNAPL concentration in the aquitard under pumping conditions. The correlation between pumping rate and LNAPL concentration was investigated. A self-developed plexiglass sandbox model was used to simulate the migration characteristics of LNAPL in the aquitard under pumping conditions. Four experimental scenarios were designed, varying pumping rates, aquitard thicknesses, and groundwater level changes. The LNAPL concentration curve was derived by systematically tracking and analyzing LNAPL levels at various locations within the aquitard. The results indicated that higher pumping rates corresponded to increased migration of LNAPL, resulting in greater LNAPL ingress into the pumping well during extraction. A thicker aquitard demonstrated a more pronounced inhibitory effect on LNAPL, leading to an extended penetration time of LNAPL within the aquitard. The drawdown within the aquitard exerted a discernible influence on LNAPL migration, with the LNAPL concentration continuing to decrease in tandem with declining water levels during pumping. These research findings can establish a scientific foundation for the control and remediation of contaminants within aquitards. [ABSTRACT FROM AUTHOR]

The evaluation and monitoring of sites contaminated with heavy metals are essential for pollution remediation and prevention. In this study, we conducted geophysical and geochemical investigations at a site exhibiting heavy metal contamination downstream from an abandoned mine, with the aim of analyzing the extent of contamination and its temporal variation. We employed geophysical survey methods including electrical resistivity and induced polarization surveys of areas contaminated with heavy metals. Repeated surveys were conducted over time using the electrical resistivity method. Numerical simulations were employed to mitigate and eliminate electrical noise stemming from topography on the site. Additionally, time-lapse inversion was conducted on the resistivity data sets to analyze the changes in resistivity caused by variations in heavy metal contaminants. In the geochemical survey, soil samples were collected from the same locations as the geophysical survey, and chemical properties including pH, water content, electrical conductivity, and cation exchange capacity were analyzed. Our results showed that with the reduction of major sources of As and Zn contamination by 50%, the time-lapse electrical resistivity inversion results indicated that the resistivity of the subsurface materials increased by a factor of two. This paper demonstrated the natural reduction of the heavy metal contaminants at the site due to rainfall, aiming to comprehensively analyze the resultant alteration of both geochemical and geophysical properties. [ABSTRACT FROM AUTHOR]

Global crop yield and growth are severely impacted by hazardous heavy metal contamination of the soil and water. Hence, this study examined the effects of three different levels of cadmium (Cd) stress (concentrations of 0, 1.5, and 2.25 mM) and the foliar application of a biostimulant, i.e. Moringa leaf extract (MLE), on a range of physiological, biochemical, and morphological parameters of two canola (Brassica napus L.) cultivars, Punjab (V1) and Super (V2). More Cd was accumulated in both the aerial and subterranean sections of V1 than in V2. The morphological and physiological indicators showed a substantial (p < 0.05) deterioration as a result of the Cd buildup. The ascorbic acid, malondialdehyde (MDA), and hydrogen peroxide (H2O2) levels were considerably (p < 0.05) elevated under Cd stress. V1 had considerably higher H2O2 levels than V2, which suggests that the oxidative stress levels were higher. Additionally, the activity of some antioxidant enzymes, such as catalase and peroxidase (POD) (65% and 40%, respectively), were decreased by the higher concentration of Cd (2.25 mM). V2 demonstrated stronger antioxidant defense mechanisms than V1, as seen by a 115% increase in POD activity, a 70% increase in shoot fresh weight, and a 49% increase in amino acids following the MLE application. Despite this, V2 was still able to withstand the Cd. Under Cd stress, the foliar treatment of MLE increased the yield, growth, biochemical, and physiological characteristics of both V1 and V2. The findings indicated that applying MLE foliar spray can improve crop productivity and lessen the impacts of metals on B. napus L. [ABSTRACT FROM AUTHOR]

Bioremediation stands as a promising solution amid the escalating challenges posed by environmental pollution. Over the past 25 years, the influx of synthetic chemicals and hazardous contaminants into ecosystems has required innovative approaches for mitigation and restoration. The resilience of these compounds stems from their non-natural existence, distressing both human and environmental health. Microbes take center stage in this scenario, demonstrating their ability of biodegradation to catalyze environmental remediation. Currently, the scientific community supports a straight connection between biorefinery and bioremediation concepts to encourage circular bio/economy practices. This review aimed to give a pre-overview of the state of the art regarding the main microorganisms employed in bioremediation processes and the different bioremediation approaches applied. Moreover, focus has been given to the implementation of bioremediation as a novel approach to agro-industrial waste management, highlighting how it is possible to reduce environmental pollution while still obtaining value-added products with commercial value, meeting the goals of a circular bioeconomy. The main drawbacks and challenges regarding the feasibility of bioremediation were also reported. [ABSTRACT FROM AUTHOR]

Ciprofloxacin (CPX), is a broad-spectrum fluoroquinolone antibiotic widely used to treat bacterial infections in humans and animals. In recent years, ecological problems caused by the disposal of CPX-waste product have attracted increasing attention. This study aimed to evaluate the ability of different bacteria to remove CPX from water. The ability of five bacterial strains namely; Acenitobacter sp., Acenitobacter lwofii, Bacillus. pumilus, Burkholderia phytofirmans, and Mesorihizobium sp. were examined in this study. Tests were performed on Luria Bertani (LB) as well as on Mueller-Hinton (MH) agar at different CPX concentrations (20-100 mg L-1). All five tested bacterial strains showed growth on LB as well as on MH agar plates at all concentrations between 20 to 100 mg L-1 CPX. Three bacterial species: Acenitobacter lwofii, Bacillus pumilus, and Mesorihizobium sp. were reported more resistant to CPX of the five strains tested. In a shake flask study, the strain B. pumilus initially showed higher degradation rate (75.53%) followed by Acenitobacter lwofii (72.3%), Mesorihizobium sp. (70.32), Burkholderia phytofirmans (67.10%), and Acenitobacter sp. (63.2%) at low CPX concentration (5 mg L-1) in minimal saline media. However, Mesorihizobium sp. showed higher degradation efficiency (76.32%) at a higher CPX concentration (10 mg L-1). A group of three bacterial strains, A. lowfi, B. pumilus, and Mesorihizobium sp. showed good CPX degradation rate (95.4%), and achieved higher degradation efficiency than the single strains at 20 mg L-1 CPX concentration. Overall, the results suggest that using a combination of bacteria may be a useful tool for the remediation of antibiotic pollution. In addition, this study reveals the ability of previously isolated bacteria to biodegrade CPX as a sole source of carbon, providing new insights into the biodegradation of CPX. [ABSTRACT FROM AUTHOR]

Areas contaminated with cadmium require remediation because it is a highly toxic element. The aim of this study was to assess the Cd tolerance of four grass species (Poa pratensis, Lolium perenne, Festuca rubra, and Festuca pratensis) and to identify the most useful grass for the phytostabilization of areas with extremely high Cd content in the soil. Additionally, the relationship between grass tolerance to Cd and the glutathione (GSH) content in shoots was examined. Two series of pot experiments were carried out using soil artificially contaminated with Cd. Three levels of contamination were used—30, 60, and 130 mg kg−1 Cd—against a control. The plants were cut down 2 months after sowing. At the Cd1 level, L. perenne showed the highest tolerance to Cd (tolerance index TI = 86), while P. pratensis had the lowest tolerance (TI = 65). At Cd2, the TIs ranged from 52 to 59, indicating a similar tolerance of all species. Cd3 was most harmful to L. perenne (TI = 24), while P. pratensis was the most tolerant (TI = 31). Grassroots accumulated much more Cd than shoots. L. perenne showed the greatest increase in root Cd at each contamination level, followed by F. pratensis and then P. pratensis and F. rubra. It is noteworthy that the tolerance of grasses to Cd3 was related to the GSH content in shoots. P. pratensis and F. rubra increased the GSH content 4.6 and 3.6 times, respectively, while L. perenne and F. pratensis only increased it 2.3 times compared to the control plants. [ABSTRACT FROM AUTHOR]

Now more than ever, research into environmental management has gained relevance. Carbon quantum dots (CQDs) have recently been considered a valuable asset to this field, as their tunable fluorescence, adaptable surface chemistry and behavior as both electron acceptors or donors are chemical properties of paramount importance. This newfound interest emerged in the scientific community, and propelled CQDs to be utilized in diverse strategies for environmental remediation and pollution containment. Thus, this review will thoroughly examine how the several stages of CQDs life cycle can be exploited in the protection of the environment and hence, have a role in the Sustainable Development Goals of the United Nations. Starting with their production, several techniques for green synthesis of CQDs resorting to biomass and waste products will be discussed. Then, the applications of CQDs in pollution sensing, degrading, and adsorbing will be the focus. The role of CQDs in clean energy generation will also be described, namely their inclusion in solar cells, solar‐thermal convertors, and hydrogen evolution processes. Lastly, current challenges and limitations to the widespread use of CQDs will be addressed, followed by considerations on the contribution that CQDs may provide upon their pervasive implementation. [ABSTRACT FROM AUTHOR]

In this work, green method to synthesize chromium-doped zinc oxide (ZnO) nanorods (NRs) using an aqueous flower extract from Rhododendron arboretum is explored. Herein, chromium-doped ZnO NRs were prepared with different amount of chromium doping, varied as 2–10%. The green synthesized products underwent substantial analysis through X-ray diffraction (XRD), spectroscopic such as ultraviolet spectroscopy(UV-Vis) and scanning electron microscopy (SEM) methods. All samples were found to have hexagonal wurtzite ZnO, with average particle sizes of 52.41, 56.6, 54.44, 53.05, and 56.99 nm, respectively, for 2, 4, 6, 8, and 10% chromium doping in ZnO NRs. The Cr-doped ZnO NRs exhibited remarkable photocatalytic degradation activity of cationic dyes under UV-light, i.e., Malachite Green and Fuchsin Basic with degradation of 99.604 and 99.881%, respectively in 90 min. The reusability tests for these green synthesized Cr-doped ZnO NRs have also been carried out, showed 9–11 cycles with 85% of degradation efficiency. In addition, the Cr-doped ZnO NRs exhibited high selectivity for cationic dyes when experiments against mixture of dyes were performed. Photodegradation kinetics followed the pseudo-first-order model. The flower-extract-stabilized chromium-doped ZnO NRs demonstrated high photocatalytic activity toward malachite green and fuchsin basic dyes, potential material for pollution remediation. Cr-doped ZnO NRs by green method using flower extract of Rhododendon arboretum were prepared for the first time under ambient reaction conditions. Effect of Dopant i.e. Cr on Photocatalytic activity have been exploited. Selective photocatalytic degradation of cationic dyes i.e. MG, and FB has been achieved in 60–90 minutes. Optimization of reaction condition and various parameters has also been carried out. Recyclability of Cr-doped ZnO NRs was also evaluated and were found to be reusable for 11 cycles for degradation. [ABSTRACT FROM AUTHOR]

Nitrogen is an essential nutrient for living organisms in peat and marine soils, and its transformation within the soil matrix is a complex process mediated by various microbes that inhabit these ecological niches. The metabolism of nitrogen is governed by microbially mediated biogeochemical transformations, such as nitrification, anammox, and denitrification, which contribute to the assimilated pool of nitrogen and fixed nitrogen loss. One of the major challenges facing the field of peat and marine microbiology is the lack of understanding of the correlation between ecosystem-driven nitrogen transformation and microbial diversity. This is crucial because of growing concerns regarding the impacts of human-induced activities and global climate change on microbial nitrogen-cycling processes in peat and marine soils. Thus, this review aimed to provide a comprehensive overview of the current understanding of the microbial communities involved in peat and marine nitrification, anammox, and denitrification; the factors influencing the niche differentiation and distribution of the main functional components; the genes involved; and the main effects of human-induced activities and global climate change on the peat and marine nitrogen cycle. The implications of this review will facilitate an understanding of the complex mechanisms associated with ecosystem function in relation to nitrogen cycling, the role of peat and marine soils as carbon sinks, pollution remediation using naturally occurring populations of diverse microbes, and the development of policies to mitigate the effects of anthropogenic influences in peat and marine soils. [ABSTRACT FROM AUTHOR]

This study aims to contribute to the characterization of Katangese Copperbelt's (DR Congo) mining wastes and soils polluted with trace metals, using pollution indices and direct concentration measurements. This study also evaluated the use of these indices in assessing the success of remediation projects. Data from previous studies and samples collected from six types of discharge and one polluted soil were used to address the first objective. Soil and plant samples were collected at Kipushi and Penga Penga for the second objective. The results reveal very high concentrations of As, Cd, Co, Cu, Mn, Pb, and Zn in all mine tailings and polluted soils, compared with local references. The degree of contamination (DC) values (from 72 to 5440) and potential ecological risk (RI) values (from 549 to 162,091) indicate very high-risk situations associated with polluted discharges and soils. Regarding revegetation trials, the results show lower concentrations and RIs in tree rhizospheres compared with unamended areas at both sites. However, trace metal concentrations are higher in tree rhizospheres compared with local references, and RI values are in the considerable risk range for Penga Penga (RI = 533) and in the very high range (>1500) for Kipushi. Bioconcentration factor values are below 1, indicating low accumulation in roots, wood, and leaves, and low risk of contamination of the trophic chain. In this context, it seems that the pollution indices used are suitable for characterizing pollution and prioritization for remediation. However, there seems unsuitable for assessing the effectiveness of phytotechnology processes based on metal stabilization. Direct plant performance measurements combined with direct measurements of metals in substrates and plants to assess transfer and efficiency are more appropriate. [ABSTRACT FROM AUTHOR]

Antibiotics' ability to treat bacterial infections has long been seen as a pillar of modern medicine. Antibiotic abuse and widespread overuse, however, have resulted in unexpected consequences that call for significant adjustments in policy to be mitigated. High levels of antibiotic emissions from manufacturing facilities may help to develop new types of resistant bacteria. Such pollution is acknowledged by many scientists, business leaders, decision‐makers, and other interested parties as an unneeded and intolerable risk to public health worldwide. Antibiotics are frequently produced by soil microorganisms. The bacteria and fungi are microorganisms that produce antibiotics that are helpful in preventing or treating disease. With the invention of Penicillin, antibiotics gained widespread recognition. Since then, they have fundamentally changed how bacterial infections in animals and humans are treated. Since a significant portion of antibiotics are released from human and animal bodies without being degraded, this means that various environmental components, including soils and river water, are contaminated with antibiotics. In this case, it is anticipated that the structure and productivity of the microbiota inhabiting such environments may be impacted by the varied concentration of this type of microbial inhibitor present in different ecosystems. This effect can take place at various levels, including modifications to the population's overall structure, the selection of resistant species, or changes to bacterial physiology. [ABSTRACT FROM AUTHOR]

Siderophores are a class of small molecules renowned for their high iron binding capacity, essential for all life forms requiring iron. This article provides a detailed review of the diverse classifications, and biosynthetic pathways of siderophores, with a particular emphasis on siderophores synthesized via nonribosomal peptide synthetase (NRPS) and non-NRPS pathways. We further explore the secretion mechanisms of siderophores in microbes and plants, and their role in regulating bioavailable iron levels. Beyond biological functions, the applications of siderophores in medicine, agriculture, and environmental sciences are extensively discussed. These applications include biological pest control, disease treatment, ecological pollution remediation, and heavy metal ion removal. Through a comprehensive analysis of the chemical properties and biological activities of siderophores, this paper demonstrates their wide prospects in scientific research and practical applications, while also highlighting current research gaps and potential future directions. [ABSTRACT FROM AUTHOR]

Biochar is a promising pyrolysed carbon-enriched soil amendment and has excellent properties for agriculture production and to remediate environmental pollution. A set of reviews were conducted on biochar production by pyrolysis process from various waste biomass which has drawn extensive interest due to the low cost of production with several benefits. As many potential technologies have been developed, there are still several knowledge gaps that have been identified for some key points to contribute a comprehensive study towards soil fertility, nutrient and water retention, soil microbial activity, plant growth and yield, pollution remediation, mitigation of greenhouse gas emission and an improvement in the farmer's economy to achieve maximum profit by adopting environmentally friendly technique "pyrolysis". Therefore, this review explored a detailed study on food waste biochar production by the pyrolysis process and its impact on different applications as an amendment. Slow pyrolysis process at low and medium temperatures is a potential amendment for agriculture production and soil and water remediation by enhancing biochar properties like carbon, BET surface area, cation exchange capacity, zeta potential, and nutrient content, etc. with minimum ash content. The biochar enhances soil water and nutrient retention capacity, crop yield, and improved microbial community at different soil quality. Additionally, food waste to biochar is a realistic adsorbent and economical carbon sequester to mitigate GHG emissions. This review conducted a brief assessment of the knowledge gaps and future research directions for researchers, encouraging investigators, stakeholders, and policymakers to make the best possible decision for food waste valorization. Highlights: • Valorization of food waste to biochar is a promising amendment for agriculture and soil–water remediation. • Lower and medium pyrolysis temperatures qualitatively changed all aspects of biochar properties. • Biochar improves soil fertility, microbial activity, soil water and nutrient retention capacity, and plants growth. • Biochar is a good carbon sequestrator to mitigate greenhouse gas and a bioeconomy product for the farmer's community and policymakers. [ABSTRACT FROM AUTHOR]

With the increasing concern about antimony (Sb) pollution and remediation in aquatic ecosystems, more and more feasible technologies have been developed. Adsorption has been extensively studied due to the simplicity of its operation and its minimal environmental effects, but the lack of cheap and stable adsorbents has limited its application in Sb treatment. In this study, pseudo-boehmite (PB) was successfully synthesized via aluminum isopropylate hydrolysis, and its potential for removing Sb(V) from wastewater was explored. The removal efficiency of Sb(V) was 92.50%, and the maximum adsorption capacity was 75.25 mg/g under optimal conditions (pH 5.0, 2 g·L−1 PB, and 10 mg·L−1 Sb(V)). In addition, better performance could be obtained at acidic conditions (pH 3.0–5.0). Surface complexation, electrostatic attraction, and hydrogen bonding were identified as potential major processes for Sb(V) elimination by PB based on experimental and characterization data. This study presents a promising approach for the efficient removal of Sb(V) from wastewater, offering a new insight into the application of aluminum-based materials for heavy metal removal. [ABSTRACT FROM AUTHOR]

Clay minerals are abundant on Earth and have been crucial to the advancement of human civilization. The ability of clay minerals to absorb chemicals is frequently utilized to remove hazardous compounds from aquatic environments. Moreover, clay-based adsorbent products are both environmentally acceptable and affordable. This study provides an overview of advances in clay minerals in the field of groundwater remediation and related predictions. The existing literature was examined using data and information aggregation approaches. Keyword clustering analysis of the relevant literature revealed that clay minerals are associated with groundwater utilization and soil pollution remediation. Principal component analysis was used to assess the relationships among clay mineral modification methods, pollutant properties, and the Langmuir adsorption capacity (Qmax). The results demonstrated that pollutant properties affect the Qmax of pollutants adsorbed by clay minerals. Systematic cluster analysis was utilized to classify the collected data and investigate the relationships. The pollution adsorption mechanism of the unique structure of clay minerals was investigated based on the characterization results. Modified clay minerals exhibited changes in surface functional groups, internal structure, and pHpzc. This review provides a summary of recent clay-based materials and their applications in groundwater remediation, as well as discussions of their challenges and future prospects. [ABSTRACT FROM AUTHOR]

Many environmental and industrial processes depend on how fluids displace each other in porous materials. However, the flow dynamics that govern this process are still poorly understood, hampered by the lack of methods to measure flows in optically opaque, microscopic geometries. We introduce a 4D microvelocimetry method based on high-resolution X-ray computed tomography with fast imaging rates (up to 4 Hz). We use this to measure flow fields during unsteady-state drainage, injecting a viscous fluid into rock and filter samples. This provides experimental insight into the nonequilibrium energy dynamics of this process. We show that fluid displacements convert surface energy into kinetic energy. The latter corresponds to velocity perturbations in the pore-scale flow field behind the invading fluid front, reaching local velocities more than 40 times faster than the constant pump rate. The characteristic length scale of these perturbations exceeds the characteristic pore size by more than an order of magnitude. These flow field observations suggest that nonlocal dynamic effects may be long-ranged even at low capillary numbers, impacting the local viscous-capillary force balance and the representative elementary volume. Furthermore, the velocity perturbations can enhance unsaturated dispersive mixing and colloid transport and yet, are not accounted for in current models. Overall, this work shows that 4D X-ray velocimetry opens the way to solve long-standing fundamental questions regarding flow and transport in porous materials, underlying models of, e.g., groundwater pollution remediation and subsurface storage of CO2 and hydrogen. [ABSTRACT FROM AUTHOR]

Spatially confined photocatalysis has emerged as a viable strategy for the intensification of various redox reactions, but the influence of confined structure on reaction behavior is always overlooked in gas‐solid reactions. Herein, we report a nanomembrane with confining Cs3Bi2Br9 nanocrystals inside vertical channels of porous insulated silica thin sheets (CBB@SBA(⊥)) for photocatalytic nitric oxide (NO) abatement. The ordered one‐dimensional (1D) pore channels with mere 70 nm channel length provide a highly accessible confined space for catalytic reactions. A record‐breaking NO conversion efficiency of 98.2 % under a weight hourly space velocity (WHSV) of 3.0×106 mL g−1 h−1, as well as exceptionally high stability over 14 h and durability over a wide humidity range (RH=15–90 %) was realized over SBA(⊥) confined Cs3Bi2Br9, well beyond its nonconfined analogue and the Cs3Bi2Br9 confine in Santa Barbara Amorphous (SBA‐15). Mechanism studies suggested that the insulated pore channels of SBA(⊥) in CBB@SBA(⊥) endow concentrated electron field and enhanced mass transfer that render high exposure of reactive species and lower reaction barrier needs for ⋅O2− formation and NO oxidation, as well as prevents structural degradation of Cs3Bi2Br9. This work expands an innovative strategy for designing efficient photocatalysts for air pollution remediation. [ABSTRACT FROM AUTHOR]

There is growing concern regarding cadmium (Cd) exposure through rice consumption. Compared with alternate wetting and drying (AWD), continuous flooding (CF) is usually considered as an effective approach for reducing Cd enrichment in rice but increases the risk of pollution from arsenic (As). In this study, the field trial was conducted to investigate remediation effects of two water management (CF and AWD) techniques on Cd pollution in rice in typical japonica rice cultivation areas with varied soil pH levels. The results indicate that soil pH was a crucial factor in regulating CF-mediated Cd/As accumulation and migration in rice plants, and grains at all stages of rice growth. In acidic fields, compared with AWD, the use of CF reduced the accumulation of Cd in plants during the tillering stage; CF during the milk stage promotes the risk of contamination of Cd in rice grains and any form of As in plants and inhibits the content of any forms of As in grains. During the mature stage, CF reduced the levels of Cd in the plants and grains while promoting the accumulation of As(V) and total As(T-As) in plants and As(III) in grains. In alkaline fields, compared with AWD, CF during the tillering stage promoted the accumulation of various forms of As in plants. During the milk stage, CF increased and decreased the Cd content in plants and grains, respectively, and reduced the accumulation of T-As in plants and As(III) in grains; during the mature stage, CF promoted the accumulation of Cd in plants and grains, induced the accumulation of T-As plants, and inhibited the accumulation of any form of As in grains. From the perspective of food safety, the impact of CF conditions on the accumulation of Cd and As in rice from acidic fields exhibited a pattern of reduction in Cd and increase in As during the maturity period, as compared to that on the AWD. Conversely, CF increased the Cd risk while simultaneously reducing the As accumulation in rice grains to a safe level in alkaline fields. CF is not recommended as a remediation strategy for Cd pollution in rice in low Cd pollution areas, but it can be considered as a potential strategy for As pollution remediation in rice in alkaline fields with low Cd pollution. [ABSTRACT FROM AUTHOR]

The radicals and high temperatures generated by the Oxyhydrogen flame induce new reactions. This paper reports on the treatment of saturated chloride solutions with Oxyhydrogen flame. The results show that the oxyhydrogen flame can promote the hydrolysis definitely, including strong acid and strong alkali salts like NaCl and KCl. The extent and product of the hydrolysis depends on the Lewis acidity and hardness of the metal ions in the chlorides. The higher is the Lewis acidity of metal ions, and the higher is the extent of hydrolysis, thus the efficiency of oxyhydrogen flame (EH) of AlCl3 is the highest, up to 2.95%, as Al3+ is the strongest Lewis acid. Soft metals tend to produce basic chloride, and the harder ones prefer the oxides, carbonates or hydroxides. Through the exploration of this paper the authors believe that the hydroxide flame can be a universal method for treating any kind of chemical waste. [ABSTRACT FROM AUTHOR]

Since the advent of the industrial revolution, there has been a constant need of efficient catalysts for abatement of industrial toxic pollutants. This phenomenon necessitated the development of eco-friendly, stable, and economically feasible catalytic materials like lanthanum-based perovskite-type oxides (PTOs) having well-defined crystal structure, excellent thermal, and structural stability, exceptional ionic conductivity, redox behavior, and high tunability. In this review, applicability of La-based PTOs in remediation of pollutants, including CO, NOx and VOCs was addressed. A framework for rationalizing reaction mechanism, substitution effect, preparation methods, support, and catalyst shape has been discussed. Furthermore, reactant conversion efficiencies of best PTOs have been compared with noble-metal catalysts for each application. The catalytic properties of the perovskites including electronic and structural properties have been extensively presented. We highlight that a robust understanding of electronic structure of PTOs will help develop perovskite catalysts for other environmental applications involving oxidation or redox reactions. [ABSTRACT FROM AUTHOR]