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This study introduces a series of Fe/Mn-GOCS composites using high-temperature impregnation with graphene oxide and chitosan as substrates, modified by diverse manganese salts, including MnCl2∙4H2O, KMnO4, and MnSO4. Among these, FeCl2/MnSO4-GOCS demonstrated the highest adsorption capacity for Sb(III), peaking at 57.69 mg/g. The adsorption performance was extensively evaluated under various conditions, such as different initial concentrations, pH levels, solid–liquid ratios, and adsorption durations. It was observed that when the Fe/Mn molar ratio exceeded 4:1, there was a notable decrease in both the adsorption capacity and removal rate. Kinetic analyses using the pseudo-second-order model revealed a better fit (R2 > 0.99) compared to the pseudo-first-order model, indicating that chemisorption dominated the adsorption process. Additionally, isothermal modeling highlighted the efficiency of Fe/Mn-GOCS, particularly in high-concentration environments, with the Sips model demonstrating the best fit, integrating characteristics of both Langmuir and Freundlich models. These results not only offer a robust theoretical and practical basis for efficient Sb(III) removal but also underscore the potential of multi-metal-modified adsorbents as sustainable solutions for environmental remediation. [ABSTRACT FROM AUTHOR]

Ecological floating beds, with their compact footprint and mobility, offer a promising solution for sustainable surface water remediation in rural areas. However, low removal efficiency and instability still limit its application. In this study, iron–carbon-based fillers were integrated into ecological floating beds to investigate their impact and mechanisms in removing pollutants, including carbon, nitrogen, phosphorus, and heavy metals. Results indicate that all five fillers (activated carbon, iron–carbon fillers, sponge iron, activated carbon + iron–carbon fillers, and activated carbon + sponge iron) can completely remove orthophosphate, and the sponge iron filler system can completely remove nitrate. Then, fillers were applied to ecological floating beds, and the iron–carbon microelectrolysis (activated carbon + sponge iron filler)-enhanced ecological floating bed showed superior removal efficiency for pollutants. It achieved 95% removal of NH4+-N, 85% removal of NO3−-N, 75% removal of total phosphorus, 90% removal of chemical oxygen demand, and 90% removal of heavy metals. Typical nitrifying bacteria Nitrospira, denitrifying bacteria Denitratisoma, and a variety of bacterial genera with denitrification functions (e.g., Rhodobacter, Dechloromonas, Sediminibacterium, and Novosphingobium) coexisted in the system, ensuring efficient and robust nitrogen removal performance. These findings will provide support for the sustainable treatment of surface water in rural areas. [ABSTRACT FROM AUTHOR]

The increasing prevalence of heavy metal pollution in various environmental components presents a critical challenge to global sustainability. This review synthesizes recent advancements in the sustainable use of natural and waste-derived materials for the environmental decontamination, focusing on cost-effective, eco-friendly, and versatile adsorbents. It contrasts conventional remediation methods, which are often expensive, resource-intensive, and environmentally taxing, with innovative alternatives that utilize agricultural residues, industrial by-products, and marine-based materials. Key materials discussed include clays, zeolites, biochar, chitosan, and agricultural waste such as fruit peels and rice husks, each of which exhibits unique adsorption capabilities due to properties like high cation exchange capacity and surface functionalization. The review further explores composite materials that combine these natural adsorbents with nanoparticles, enhancing their effectiveness in removing diverse pollutants through mechanisms like ion exchange, complexation, and electrostatic attraction. Advances in chemical, thermal, and physical modification techniques are also highlighted for their ability to improve adsorption efficiency, making these materials more adaptable to complex contamination scenarios. Sustainable materials such as peat moss and algae-based sorbents are shown to be particularly valuable in decentralized and rural applications, where conventional approaches may be impractical or prohibitively expensive. The environmental and economic benefits of using natural and waste-derived materials, including lower greenhouse gas emissions, biodegradability, and alignment with circular economy principles, are emphasized. These materials offer promising potential for achieving stringent environmental standards and improving ecosystem resilience against heavy metal contamination. By bridging the gap between sustainable material science and environmental remediation, this study underscores the role of renewable, low-cost sorbents in the future of pollution management and environmental restoration. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Anthropogenic activities have left a legacy of contaminated vacant land, which disproportionately affects lower income communities and can have detrimental impacts on human health, particularly children. A management solution is needed to address this widespread lead contamination in urban soils of vacant lots. In this study, high-Fe biosolids incinerator ash (BIA) was evaluated for its ability to sequester soil Pb. Five blends were created using BIA and different amount of other products (dredge, biosolids compost, and yard waste compost) to determine the most effective treatment to reduce Pb bioaccessibility in the soil. The sorption capacity of the BIA for Pb was evaluated by mixing the BIA with Pb(NO3)2 at 1000 to 100,000 ​mg ​Pb/kg BIA. The contaminated soil from Cleveland, OH was treated with five BIA-based blends at a 1:1 (w/w) ratio, and Pb bioaccessibility was evaluated using USEPA Method 1340 ​at pH 2.5 and the Physiologically Based Extraction Test (PBET) at pH 2.5. BIA was a strong sorbent for Pb, sorbing ∼100% of the Pb from solution at 10,000 ​mg/L with only 41% bioaccessibility based on Method 1340 ​at pH 2.5. The blend containing 4.5%, 10%, or 19% BIA reduced the Pb bioaccessibility by 48% from the control based on both bioaccessibility methods. The bioaccessible Pb determined by PBET was less than that by USEPA Method 1340 ​at pH 2.5. However, similar reductions in bioaccessible Pb between blend-treated soils and the unamended soil were observed for all bioaccessibility methods. Plant growth assays showed the blends to have little to no significant impact on clover growth, mortality, or flower production, with the blend containing 10% BIA showing greater biomass yield. Results showed BIA-based blends were able to reduce bioaccessible Pb in the soil. This remediation approach may improve the urban living environment and protects public health.

Abstract Background The escalating concern regarding the environmental impact of plastic waste necessitates the adoption of biodegradable methodologies to curtail its adverse effects. A profound comprehension of the intricate interplay between bacteria and polymers becomes imperative for devising effective solutions to address plastic-induced environmental challenges. Main body of the abstract Numerous microorganisms have evolved specialized mechanisms for the degradation of plastics, rendering them amenable to application in green chemistry for the elimination of hazardous plastics from the ecosystem. This article offers a comprehensive survey of contemporary microbial bioremediation approaches geared towards augmenting plastic waste management and ameliorating plastic pollution. Emphasis is placed on elucidating the potential of microorganisms in mitigating the deleterious repercussions of plastics on ecosystems and human health, underscoring the significance of advanced strategies in green chemistry for sustainable plastic pollution mitigation. Short conclusion Current research emphasizes the effectiveness of naturally occurring soil microorganisms, particularly fungi like Aspergillus and bacteria like Bacillus, in breaking down plastics. To harness this potential on a broader scale, optimization of microbial activity conditions and pre-treatment with environmentally beneficial compounds are essential.

The routine dredging of waterways produces huge volumes of sediments. Handling contaminated dredged sediments poses significant and diverse challenges around the world. In recent years, novel and sustainable ex situ remediation technologies for contaminated sediments have been developed and applied. This review article focuses on cement-based binders in stabilizing contaminants through the stabilization/solidification (S/S) technique and the utilization of contaminated sediments as a resource. Through S/S techniques, heavy metals can be solidified and stabilized in dense and durable solid matrices, reducing their permeability and restricting their release into the environment. Industrial by-products like red mud (RM), soda residue (SR), pulverized fly ash (PFA), and alkaline granulated blast furnace slag (GGBS) can immobilize heavy metal ions such as lead, zinc, cadmium, copper, and chromium by precipitation. However, in a strong alkali environment, certain heavy metal ions might dissolve again. To address this, immobilization in low pH media can be achieved using materials like GGBS, metakaolin (MK), and incinerated sewage sludge ash (ISSA). Additionally, heavy metals can be also immobilized through the formation of silicate gels and ettringites during pozzolanic reactions by mechanisms such as adsorption, ion exchanges, and encapsulation. It is foreseeable that, in the future, the scientific community will increasingly turn towards multidisciplinary studies on novel materials, also after an evaluation of the effects on long-term heavy metal stabilization. [ABSTRACT FROM AUTHOR]

Environmental context: Mitigating the environmental fallout of industrial accidents is crucial. In a recent study, researchers conducted tests on model substrates to explore the effectiveness of bioremediation in treating complex refinery contaminants resulting from both accidental and deliberate facility damage. The research reveals that bioremediation can be a promising, eco-friendly solution for cleaning up such pollutants, aligning with broader efforts to combat environmental harm resulting from industrial incidents. Rationale: Bioremediation harnesses microorganisms' diverse metabolic abilities to detoxify and eliminate pollutants, particularly hydrocarbon-based ones such as oil. This natural biodegradation process performed by microorganisms is a cost-effective method for environmental cleanup compared to other remediation technologies. Methodology: In this study, we examined the fate of heavy metals, cobalt and molybdenum, by the analysis of the basic chemical parameters of other sample components, such as n -hexane extractable substances and total petroleum hydrocarbons. The metal content was determined using inductively coupled plasma–optical emission spectrometry (ICP-OES). Exchangeable (loosely bound to the surface of particles and due to its high mobility and availability is crucial for understanding the potential immediate impact of metal contamination) and more stable fractions of the metal and the metal forms were determined using a sequential extraction method. The phase composition of the samples was determined by X-ray diffraction. Results: In our microbiological analysis, we isolated various cultures from a consortium of microorganisms. Basic chemical analysis indicators, such as n -hexane extractable substances, total petroleum hydrocarbons and humic acids, reflected robust microbiological activity. During the study, metals in exchangeable form decreased and those in more stable forms increased. Discussion: The sequential extraction of cobalt and molybdenum revealed shifts in various metal fractions within the bioaugmented substrate post-bioremediation, differing from the initial substrate. These alterations in metal fractions are likely attributable to microbial actions, leading to the formation of more stable metal fractions throughout the bioremediation process. Environmental context. Mitigating the environmental fallout of industrial accidents is crucial. In a recent study, researchers conducted tests on model substrates to explore the effectiveness of bioremediation in treating complex refinery contaminants resulting from both accidental and deliberate facility damage. The research reveals that bioremediation can be a promising, eco-friendly solution for cleaning up such pollutants, aligning with broader efforts to combat environmental harm resulting from industrial incidents. [ABSTRACT FROM AUTHOR]

Background: The escalating concern regarding the environmental impact of plastic waste necessitates the adoption of biodegradable methodologies to curtail its adverse effects. A profound comprehension of the intricate interplay between bacteria and polymers becomes imperative for devising effective solutions to address plastic-induced environmental challenges. Numerous microorganisms have evolved specialized mechanisms for the degradation of plastics, rendering them amenable to application in green chemistry for the elimination of hazardous plastics from the ecosystem. This article offers a comprehensive survey of contemporary microbial bioremediation approaches geared towards augmenting plastic waste management and ameliorating plastic pollution. Emphasis is placed on elucidating the potential of microorganisms in mitigating the deleterious repercussions of plastics on ecosystems and human health, underscoring the significance of advanced strategies in green chemistry for sustainable plastic pollution mitigation. Short conclusion: Current research emphasizes the effectiveness of naturally occurring soil microorganisms, particularly fungi like Aspergillus and bacteria like Bacillus, in breaking down plastics. To harness this potential on a broader scale, optimization of microbial activity conditions and pre-treatment with environmentally beneficial compounds are essential. [ABSTRACT FROM AUTHOR]

With the advancement in industrialization and to cope with the ever-increasing demand for food, the farmer community is compelled to use various approaches, including the excessive use of phosphatic fertilizers, irrigation with contaminated water, and limited access to alternative inputs. These practices have resulted in cadmium toxicity. The present study aimed to assess the efficacy of four organic amendments including press mud, sugar cane bagasse, humic acid, and biochar along with four inorganic amendments including gypsum, CaCl2, iron and silicon nanoparticles in reducing the bioavailability of Cd in soil. The results revealed that the press mud treatment exhibited the highest percentage increase in growth and physiological indices, with a value of 188.63%, followed by sugarcane, humic acid, biochar, Fe, Si NPs, gypsum and CaCl2 with a percentage increase of 162.26%, 141.65%, 93.50%, 81.13%, 71.56%, 59.24%, and 12.14%, respectively. The maximum malondialdehyde (MDA) contents were recorded in the Cd treatment, and a significant inconsistency in antioxidant enzyme activity such as catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX), and Proline content was observed between organic and inorganic amendment treatments. Press mud exhibited the lowest Ab-DTPA Cd value, which was 11.96% at 100 ppm, with other treatments ranging between 15.17 and 37.01%. In conclusion, applying the studied amendments demonstrated a potential to decrease Cd bioavailability in the soil, leading to improved photosynthetic pigment levels and reduced Cd uptake by maize plants. Press mud, humic acid, gypsum, and Fe-NPs were identified as particularly effective amendments for reducing cadmium concentrations by binding in soil for reduced transport to maize, alleviating toxicity, and oxidative stress management. Additional research is necessary to determine the ideal concentrations for each treatment and their overall impact on plant growth and development. [ABSTRACT FROM AUTHOR]

The European Union (EU) has placed a strong focus on soil contamination and remediation in its Thematic Strategy for Soil Protection, emphasizing the critical need for comprehensive soil data at the EU level. To effectively support EU soil management strategies, it is necessary to develop soil-related indicators and standardized datasets across all EU member states. However, the lack of standardized methodologies for estimating the time required for contaminated site remediation is a dilemma in Italy and throughout Europe. This study examines statistical data on the time-consuming nature of the contaminated site remediation process in Italy. In fact, early intervention not only simplifies site remediation but also reduces long-term financial obligations such as monitoring costs and potential legal implications. This study categorized data according to remedial procedures, explored different management phases, and revealed different timescales for completing the procedure. The findings show that processes completed after preliminary investigations are often shorter in time than those completed following conceptual model assessments. In contrast, processes that require corrective measures typically take a longer period of time to complete. Notably, remedial interventions tend to have a shorter duration compared to risk management interventions. Furthermore, procedures that address both soil and groundwater contamination generally require more time compared to those that focus only on soil remediation. This study provides valuable insight into the time-consuming aspects of remediation procedures, recommending potential changes to regulatory frameworks to accelerate site remediation activities. [ABSTRACT FROM AUTHOR]

Water contamination is a pervasive global crisis, affecting over 2 billion people worldwide, with pharmaceutical contaminants emerging as a significant concern due to their persistence and mobility in aquatic ecosystems. This review explores the potential of activated hydrochars, sustainable materials produced through biomass pyrolysis, to revolutionize the removal of pharmaceutical contaminants from water sources. These materials possess high surface area, porous structure, and exceptional adsorption capabilities, making them a promising solution. The impact of pharmaceutical contaminants on aquatic ecosystems and human health is far-reaching, affecting biodiversity, water quality, and public health. To address this complex issue, a diverse range of techniques, including adsorption, biodegradation, and advanced oxidation processes, are employed in the pharmaceutical industry. Activated hydrochars offer substantial adsorption capacity, sustainable feedstock origins, and a minimal carbon footprint. This review highlights their potential in pharmaceutical contaminant removal and their broader applications in improving soil and air quality, resource recovery, and sustainable waste management. Interdisciplinary collaboration and the development of intelligent treatment systems are essential to fully unlock the potential of activated hydrochars. Regulatory support and policy frameworks will facilitate their responsible and widespread application, promising a cleaner and more sustainable future. This paper aims to inform scientists, environmental experts, policymakers, and industry stakeholders about the promising role of activated hydrochars in addressing pharmaceutical contaminant challenges. [ABSTRACT FROM AUTHOR]

Contamination of aquatic ecosystems with organic and inorganic contaminants is a global threat due to their hazardous effects on the environment and human health. Floating treatment wetland (FTW) technology is a cost-effective and sustainable alternative to existing treatment approaches. It consists of a buoyant mat in which wetland plants can grow and develop their roots in a suspended manner and can be implemented to treat stormwater, municipal wastewater, and industrial effluents. Here we explored the potential of bacterial-augmented FTWs for the concurrent remediation of phenol and hexavalent chromium (Cr6þ) contaminated water and evaluated treated water toxicity using Triticum aestivum L. (wheat) as a test plant. The FTWs carrying Phragmites australis L. (common reed) were inoculated with a consortium of four bacterial strains (Burkholderia phytofirmans PsJN, Acinetobacter lwofii ACRH76, Pseudomonas aeruginosa PJRS20, Bacillus sp. PJRS25) and evaluated for their potential to simultaneously remove phenol and chromium (Cr) from contaminated water. Results revealed that the FTWs efficiently improved water quality by removing phenol (86%) and Cr (80%), with combined use of P. australis and bacterial consortium after 50 days. The phytotoxicity assay demonstrated that the germination of wheat seed (96%) was significantly higher where bacterial-augmented FTWs treated water was used compared to untreated water. This pilot-scale study highlights that the combined application of wetland plants and bacterial consortium in FTWs is a promising approach for concomitant abatement of phenol and Cr from contaminated water, especially for developing countries like Pakistan where the application of advanced and expensive technologies is limited. [ABSTRACT FROM AUTHOR]

Purpose: Geogenic enrichment of cadmium (Cd) poses a grave threat to food security. Specifically, soils derived from limestone often suffer from elevated Cd levels, as well as other limitations such as low organic matter and limited availability of micronutrients. Our study aims to develop suitable soil amendments using locally available biomass materials and naturally abundant clay minerals, focusing on Cd-enriched karst soils. Materials and methods: We used biochar- and illite-smectite stratified clay-based soil amendments for the immobilization of Cd in a karst soil, and designed their formulation so that soil health can be improved simultaneously. Results and discussion: Application of rice straw biochar in combination with zero valent iron and quicklime, as well as the utilization of natural illite-smectite stratified clay alongside cow manure and quicklime, yielded the most effective results in Cd immobilization. These amendments also increased the bioavailability of selenium (Se) due to a slight elevation in soil pH. Additionally, these modifications significantly enhanced the chemical fertility of the soil, leading to elevated levels of total organic carbon (TOC), cation exchange capacity (CEC), available phosphorus (P), and available potassium (K). Furthermore, we observed an increase in microbial diversity and richness, with the identification of keystone species that dominate and improve soil health. Conclusions: The findings of this study present a low-cost and practical solution for simultaneously immobilizing geogenic Cd while also improving chemical fertility and stimulating microbial diversity in regions with a high geological background of this element. [ABSTRACT FROM AUTHOR]

The most common contaminants in the earth's crust are heavy metals. Remediation is a technique to immobilize, remove, or detoxify these metals in contaminated environments. However, after decades using conventional remediation techniques, new scientific findings indicate that these remediation operations can promote adverse impacts. Given this perspective, a sustainable remediation approach that minimizes environmental, social, and economic impacts has been growing. The objective of this work was to evaluate the chemical immobilization provided by a steel mill industrial waste from the Acid Recovery Plant (ARP) as an alternative to remediate sediments affected by cadmium, lead and zinc. The experiment consisted in adding increasing doses of an ARP industrial residue, consisting mostly of iron oxide, to sediment samples contaminated by a metallurgical industry. After the incubation period, samples from each treatment were removed and submitted to simple extractions (water, acetic acid, DTPA and sodium nitrate) and total pseudo digestion (nitro-perchloric) to determine the bioavailability of Cd, Pb and Zn. The application of the ARP residues provided the formation of complexes associated with the most stable chemical fractions, such as the fraction associated with Fe oxides (F4) and the residual fraction (F5). Treatment with 5% ARP residue was sufficient to reduce the solubility of Cd, Pb and Zn in the sediment studied. Chemical containment proved to be a promising alternative for minimizing the impact of potentially toxic elements (PTEs) in contaminated soils and sediments, as well as being viable from a sustainable point of view. [ABSTRACT FROM AUTHOR]

The persistence of organic/inorganic pollutants in the water has become a serious environmental issue. Among the different pollutants, dyes and heavy metal pollution in waterways are viewed as a global ecological problem that can have an impact on humans, plants, and animals. The necessity to develop a sustainable and environmentally acceptable approach to remove these toxic contaminants from the ecosystem has been raised. In the past two decades, rapid industrialization and anthropogenic activities in developed countries have aggravated environmental pollution. Industrial effluents that are discharged directly into the natural environment taint the water, which has a consequence for the water resources. Magnetic nanohybrids are broadly investigated materials used in the adsorption and photocatalytic degradation of poisonous pollutants present across water effluents. In the present review, the toxic health effects of heavy metals and dyes from the water environment have been discussed. This paper reviews the role of magnetic nanohybrids in the removal of pollutants from the water environment, providing an adequate point of view on their new advances regarding their qualities, connection methodologies, execution, and their scale-up difficulties. [ABSTRACT FROM AUTHOR]

Face masks, a prime component of personal protective equipment (PPE) items, have become an integral part of human beings to survive under the ongoing COVID-19 pandemic situation. The global population requires an estimated 130 billion face masks and 64 billion gloves/month, while the COVID-19 pandemic has led to the daily disposal of approximately 3.5 billion single-use face masks, resulting in a staggering 14,245,230.63 kg of face mask waste. The improper disposal of face mask wastes followed by its mismanagement is a challenge to the scientists as the wastes create pollution leading to environmental degradation, especially plastic pollution (macro/meso/micro/nano). Each year, an estimated 0.15–0.39 million tons of COVID-19 face mask waste, along with 173,000 microfibers released daily from discarded surgical masks, could enter the marine environment, while used masks have a significantly higher microplastic release capacity (1246.62 ± 403.50 particles/piece) compared to new masks (183.00 ± 78.42 particles/piece). Surgical face masks emit around 59 g CO2-eq greenhouse gas emissions per single use, cloth face masks emit approximately 60 g CO2-eq/single mask, and inhaling or ingesting microplastics (MPs) caused adverse health problems including chronic inflammation, granulomas or fibrosis, DNA damage, cellular damage, oxidative stress, and cytokine secretion. The present review critically addresses the role of face masks in reducing COVID-19 infections, their distribution pattern in diverse environments, the volume of waste produced, degradation in the natural environment, and adverse impacts on different environmental segments, and proposes sustainable remediation options to tackle environmental challenges posed by disposable COVID-19 face masks. [ABSTRACT FROM AUTHOR]

This article gives a brief review of the use of algae for remediation, including an introduction to its general principles, reported applicability, and utilization. Algae comprises of a broad fusion of photosynthesizing organisms. Based on size and morphology, algae are classified into macro- and microalgae. Algae were the first photosynthetic inhabitant on the earth surface as a result of their ability to utilize sunlight for synthesis of carbon dioxide, nutrients, water and the ability to increase atmospheric oxygen levels. Algae's growth within the environment is determined by the availability of nitrogen, carbon, phosphorous compounds, and other essential trace nutrients within the ecosystem. In line, algae enhance the air with oxygen (O2) synthesized from the photosynthetic mechanism. Phycoremediation have always utilized algae species in the clean-up of various domestic, agricultural, municipal, and industrial wastewaters. Therefore, unlike conventional technologies that have the potential for secondary pollution, high operating costs, insufficient utilization of the natural resources, and a general public health burden brought on by the potential waterborne diseases, phycoremediation technology offers a sustainable, economical, and environmentally friendly method of remediating wastewater pollutants. [ABSTRACT FROM AUTHOR]

Heavy metal contamination has occurred as a result of industrial civilization. Zinc, copper, chromium, and lead are the most prevalent heavy metal pollutants. Heavy metal contamination has arisen as a significant environmental issue on a global scale. Human and environmental health is at risk when soils are contaminated. as well as having poor engineering qualities. Solidification/Stabilization is a critical remediation strategy for polluted soils which is both efficient and cost-effective. The solidification/stabilization approach has been frequently used to rehabilitate heavy metal-contaminated areas. First, The use of gypsum to strengthen and leach polluted soils was reviewed. Also, cement/fly ash-solidified/stabilized soils have better engineering qualities. On the other hand, the global output of phosphogypsum surpasses 300 million tons, raising disposal and environmental problems every year. The efficiency of the phosphogypsum-based stabilization/solidification technique was investigated, and the methods employed biochar and chemical agents such as citric acid and FeCl3. This review examines various remediation options as well as innovative soil amendments. [ABSTRACT FROM AUTHOR]

Since conventional ecological remediation technologies are often unreliable and inefficient, the use of phytoremediation, which uses plants to restore damaged or polluted environments, has been actively developed. In particular, phytoremediation for the management of abandoned mines has gained public acceptance due to its aesthetic advantages, environmental friendliness, use of solar energy, and low remediation costs. In this article, we review the current status of the phytoremediation of abandoned mines in Korea and the challenges that are faced. The technical and policy challenges that need to be overcome for the successful application of phytoremediation in Korea are discussed, along with its potential for use in sustainable ecosystem management. To fully deploy phytoremediation technology in old mining areas, further basic and applied research are required. [ABSTRACT FROM AUTHOR]

• A novel strategy, classification, grading, and zoning (CGZ) can reduce the environmental impact of remediation by 24 %. • Pre-remediation survey, stabilizer selection and farmer compensation are key influencing factors for the CGZ strategy. • High-density sampling (e.g., 20 m) in complex/marginal areas offers enhanced life cycle environmental benefits. • Crop's bioconcentration factors may be a tradeoff factor for stabilization and crop substitution in remediation. Sustainable remediation is crucial for agricultural soil in China as 19.4 % of soil samples are contaminated by toxic substances. Current remediation strategies, classification management and pollution grading, cannot support sustainable remediation because of lacking refined zoning and over-engineering. To address these shortcomings, we synthesized a new strategy: classification, grading, and zoning (CGZ), and performed a life cycle assessment to determine its benefits. The results showed that the CGZ strategy reduced environmental impacts by 24 % and 19 % when applied in 1.45 km2 of contaminated land (3 years from survey to remediation). These reductions were attributed to optimizing remediation technologies for various planting zones and minimizing the remediation area through balancing the primary and secondary impacts of pre-surveys and the remediation itself. Meanwhile, sustaining these remediation efforts over the long term must include equitable farmer compensation based on crop type to mitigate future environmental consequences associated with farmers switching crops. [Display omitted] [ABSTRACT FROM AUTHOR]

Water contamination is a pervasive global crisis, affecting over 2 billion people worldwide, with pharmaceutical contaminants emerging as a significant concern due to their persistence and mobility in aquatic ecosystems. This review explores the potential of activated hydrochars, sustainable materials produced through biomass pyrolysis, to revolutionize the removal of pharmaceutical contaminants from water sources. These materials possess high surface area, porous structure, and exceptional adsorption capabilities, making them a promising solution. The impact of pharmaceutical contaminants on aquatic ecosystems and human health is far-reaching, affecting biodiversity, water quality, and public health. To address this complex issue, a diverse range of techniques, including adsorption, biodegradation, and advanced oxidation processes, are employed in the pharmaceutical industry. Activated hydrochars offer substantial adsorption capacity, sustainable feedstock origins, and a minimal carbon footprint. This review highlights their potential in pharmaceutical contaminant removal and their broader applications in improving soil and air quality, resource recovery, and sustainable waste management. Interdisciplinary collaboration and the development of intelligent treatment systems are essential to fully unlock the potential of activated hydrochars. Regulatory support and policy frameworks will facilitate their responsible and widespread application, promising a cleaner and more sustainable future. This paper aims to inform scientists, environmental experts, policymakers, and industry stakeholders about the promising role of activated hydrochars in addressing pharmaceutical contaminant challenges.

Heavy metal contamination has occurred as a result of industrial civilization. Zinc, copper, chromium, and lead are the most prevalent heavy metal pollutants. Heavy metal contamination has arisen as a significant environmental issue on a global scale. Human and environmental health is at risk when soils are contaminated. as well as have poor engineering qualities. Solidification/Stabilization is a critical remediation strategy for polluted soils which is both efficient and cost-effective. The solidification/stabilization approach has been frequently used to rehabilitate heavy metal-contaminated areas. First, The use of gypsum to strengthen and leach polluted soils was reviewed. Also, cement/fly ash-solidified/stabilized soils have better engineering qualities. On the other hand, the global output of phosphogypsum surpasses 300 million tons, raising disposal and environmental problems every year. The efficiency of the phosphogypsum-based stabilization/solidification technique was investigated, and the methods employed biochar and chemical agents such as citric acid and FeCl3. This review examines various remediation options as well as innovative soil amendments.

Recent devastating hurricanes demonstrated that extreme weather and climate change can jeopardize contaminated land remediation and harm public health and the environment. Since early 2016, the Sustainable Remediation Forum (SURF) has led research and organized knowledge exchanges to examine (1) the impacts of climate change and extreme weather events on hazardous waste sites, and (2) how we can mitigate these impacts and create value for communities. The SURF team found that climate change and extreme weather events can undermine the effectiveness of the approved site remediation, and can also affect contaminant toxicity, exposure, organism sensitivity, fate and transport, long-term operations, management, and stewardship of remediation sites. Further, failure to consider social vulnerability to climate change could compromise remediation and adaptation strategies. SURF's recommendations for resilient remediation build on resources and drivers from state, national, and international sources, and marry the practices of sustainable remediation and climate change adaptation. They outline both general principles and site-specific protocols and provide global examples of mitigation and adaptation strategies. Opportunities for synergy include vulnerability assessments that benefit and build on established hazardous waste management law, policy, and practices. SURF's recommendations can guide owners and project managers in developing a site resiliency strategy. Resilient remediation can help expedite cleanup and redevelopment, decrease public health risks, and create jobs, parks, wetlands, and resilient energy sources. Resilient remediation and redevelopment can also positively contribute to achieving international goals for sustainable land management, climate action, clean energy, and sustainable cities.

Extensive research to date has focused on the coagulation-flocculation and biosorption properties of the invasive Opuntia ficus-indica (L.) Mill. to remove metals from water. However, no studies have reported on the use of O. ficus-indica extract as a leaching agent to remove metals from contaminated soil. In the present work, a new environmentally friendly method for lead-contaminated soil remediation is evaluated. The method involves the use of cladode extract from O. ficus-indica as a soil washing agent. This new technique can serve to mitigate against the potential deterioration of soil quality and other secondary environmental impacts that result from the use of inorganic acids and/or chelating agents. Extractions from cladodes harvested during both day and night crassulacean acidic metabolism (CAM) phases were evaluated for treatment of lead contamination in three different soils including kaolinite, montmorillonite and a field-natural soil sample. Lead removal rates, which ranged from 44 to 100%, were significantly impacted by the intrinsic properties of the soils, the leachate dosage, the plant harvest phase, and the soil washing duration. Fourier-transform infrared spectroscopy (FTIR) characterization of the leachates indicated that functional groups present in the O. ficus-indica extracts played an essential role in the removal process. Results suggest that this species possesses promising potential to be used as a sustainable basis for the abatement of lead contaminated soil. [ABSTRACT FROM AUTHOR]

Many agricultural areas are contaminated by heavy metals to such a level that the growth of plants is drastically reduced. Based on the site's specific characteristics, feasibility studies were carried out to choose the most effective technologies. Feasibility tests showed that soil washing and phytoremediation technologies could be used at the agricultural site under study. The efficiency of the technologies is highly dependent on soil characteristics, which determine the chemical form of the metals. The results indicate that water-based soil washing can be successfully used with the possibility of reaching the remediation objectives quickly. However, the technology in the first step essentially breaks down the soil. Moreover, phytoremediation cannot be used directly to overcome the toxicity derived from the very high bioavailability of the heavy metals. Still, there is the need to use "assisted" phytoremediation by adding compost that reduces metal bioavailability, allowing phytoextraction. In this case, a longer time is needed to reach the remediation target. The results provide a preliminary scenario for decision-makers and stakeholders to assess possible technologies applicable and a possible scheme to be applied in similar cases of polluted agricultural areas. [ABSTRACT FROM AUTHOR]

Research studies on Metal Organic Frameworks (MOF) based composites and their potential applications in environmental engineering and pollution control have recently emerged. An attractive material to form MOF composites is biochar (BC); a low-cost, highly porous carbonaceous by-product of biomass pyrolysis. This paper presents a critical review on MOF-biochar composites, focusing on fabrication, characterisation, modification, and applications in environmental protection and pollution control. The adsorption mechanisms and influential parameters are systematically examined to develop an insight into interactions between MOF and biochar in remedial process. The adsorption capacity of composites is generally doubled compared to the standalone biochar, while MOFs maintain their crystallinity, even over multiple regeneration cycles, indicating the composites' long-term applicability and sustainability. These findings highlight the potential of MOF-biochar composites for environmental applications and identify key areas for further research to enhance their sustainability in environmental protection and green energy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

This paper aims to expand knowledge of the potential environmental impacts associated with the remediation of shooting ranges in peatland environments. While the remediation of these sites currently requires the excavation and disposal of contaminated soil to meet local environmental quality guideline values, there is a growing recognition that this remediation process causes substantial environmental impacts. A life cycle assessment (LCA) was undertaken to identify the life cycle impacts and potential mitigation measures to reduce them. The results showed that for the majority of impact categories, downstream landfilling processes dominated impacts; in particular, substantial greenhouse gas emissions were associated with the decomposition of carbon-rich peat soil caused by excavation and removal (119 t CO 2 equivalents, representing 67.8 % of the life cycle emissions). In addition, gravel materials used for road building was important to several impact categories. The greenhouse gas mitigation potential was 17 % and included the use of renewable fuels, electric excavators, local site equipment, material selection and the reuse of materials. While the impacts from site infrastructure and excavation may be reduced through appropriate planning and management, the greenhouse gas emissions impact from excavating carbon-rich soil is proportional to the excavated soil volume. Therefore, the acceptability of these impacts should be carefully evaluated against the benefits of reduced contaminant leaching into the receiving environment., Competing Interests: Declaration of competing interest The authors declare that they do not have financial interests or personal relationships that could influence the work reported in this study., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Nanoscale zerovalent iron (nZVI) is the main nanomaterial used in remediation processes. The aim of this study was to evaluate the sustainability of the nZVI production methods. For this, nine nZVI production methods were selected for analysis. Four kinds of life cycle analysis were performed: life cycle assessment (LCA), life cycle cost (LCC), social life cycle assessment (S-LCA), and life cycle sustainability assessment (LCSA). The LCA was performed in the SimaPro® program using the Impact 2002+ method. The LCC was also performed in SimaPro by developing a cost analysis method. For the social analysis, equations were used to calculate the social life cycle score. For the LCSA, the results of the life cycle analyses were normalized, and a weighting factor was defined on the basis of multi-criteria analysis methods. The sustainability score was calculated on the basis of a linear additive model. Scenario and sensitivity analyses were performed, and Monte Carlo simulation was used to quantify the uncertainty of the results. The system limits the stages of raw material extraction, transportation, and nZVI production. The functional unit was 1.00 kg of nZVI produced. The green synthesis method was found to be the most sustainable method, classified as highly sustainable, whereas the microemulsion method was found to be the least sustainable method, classified as unsustainable. The scenario analysis showed that overall the Swiss and Canadian scenarios have the highest sustainability index scores, whereas the Indian scenario has the lowest. In addition, the results show low sensitivity to weighting factor variation. In general, this study contributed to the state-of-the-art LCSA application on nanomaterials used in remediation. [ABSTRACT FROM AUTHOR]

Sludge hydrochar used for chromium-contaminated soil remediation is susceptible to natural aging with soil minerals, which may alter its electrochemical properties and affect its remediation performance. In this study, the effect of co-aging with soil minerals (soluble mineral salts [FeCl 3 , MnCl 2 , AlCl 3 , and CaCl 2 ] and clay minerals [kaolinite]) on the redox activity of sludge hydrochar for Cr(VI) reduction was investigated. The subsequent aging process revealed that Fe3+ and Al3+ ions oxidized the stabilized alkanes to functional groups with high electron-donating capacities, such as -OH and C-O, because of their oxidizing properties or electron-mediating facilitated by the formation of the crystal structure, while enhancing the electron-donating and electron-mediating capacities of the co-aging hydrochar. However, Mn2+ was easily oxidized to Mn(III) and Mn(IV), which protected alkanes from oxidation. Simultaneously, Ca2+ and kaolinite were encapsulated on the hydrochar surface, hindering electron-mediating during oxidation. None of the three substantially enhanced the electron-donating capacity of the hydrochar during the co-aging process. Because of the richness of soil minerals, it is vital to consider redox reactions as a critical factor when applying hydrochar for soil remediation. [Display omitted] • Appropriate natural oxidation facilitated the reduction of Cr(VI) by hydrochar. • Aging induced oxidation of hydrochar with an increase of surface O moieties. • Co-aging with Fe3+/Al3+ further increased the reducing O moieties of hydrochar. • Co-aging with Fe3+/Mn2+/Al3+ facilitated electron mediation for Cr(VI) reduction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Concentrated-solar powered thermal remediation of petroleum-contaminated soils. • Ignition of petroleum-contaminated soil is achievable with concentrated solar power. • Steel thermal receivers transmit concentrated solar energy to samples effectively. • Total petroleum hydrocarbon (TPH) analysis demonstrates effective treatment. Petroleum-contaminated soil poses an environmental risk and is costly to remediate. Self-sustaining Treatment for Active Remediation (STAR) is an emerging remediation technique that consists of igniting and propagating a smoldering front through a volume of contaminated soil. While effective, the electrical energy demand required to initiate smoldering can be cost-prohibitive in locations without robust electrical infrastructure. To address this, we investigated the viability of a novel concentrated solar power process as a low-carbon alternative to electrically driven heating for STAR. The solar-driven system uses parabolic reflectors to focus solar energy, then directs it through fiber optic bundles to flexibly transmit it to a soil column. This process is demonstrated on ∼ 750 mL samples of petroleum-contaminated soil and detectable hydrocarbons were reduced in each case. Research evaluated several parameters of interest for effective treatment including thermal receiver material and distance between solar output and thermal receiver. Temperature was measured throughout treatment and typically exceeds 400 °C prior to ignition. Steel and quartz thermal receivers show effective temperature distribution, initiating smoldering, reducing detectable hydrocarbons and maintaining durability. The results indicate that concentrated solar power can efficiently ignite smoldering remediation, showing promise as a low-carbon alternative to current methods. [ABSTRACT FROM AUTHOR]

The coupling of microscale zero-valent iron (mZVI) and anaerobic bacteria (AB) has gained increasing attention due to its ability to enhance dechlorination efficiency by combining the advantages of chemical and microbial reduction. However, the implementation of these coupling technologies at the field scale is challenging in terms of sustainability goals due to the coexistence of various natural electron acceptors in groundwater, which leads to limited electron selectivity and increased secondary risk. Therefore, this study used trichloroethylene (TCE) as a probe contaminant and nitrate (NO 3 −) as a typical co-occurring natural electron acceptor to optimize the overall sustainable remediation performance of an mZVI/AB coupled system by adjusting the mZVI particle size and dosage. Results revealed that mZVI particles of different sizes exhibit different microorganism activation capabilities. In contrast to its 2 μm and 7 μm counterparts, the 30 μm mZVI/AB system demonstrated a strong dosage-dependency in TCE removal and its product selectivity. Finally, multi-criteria analysis (MCA) methods were established to comprehensively rank the alternatives, and 30 μm mZVI (15 g/L dosage) was determined to be the best remediation strategy with the highest total sustainability score under all studied hydro-chemical conditions when equal weights were applied to technical, environmental, and economic indicators. Our work provides a paradigm for comprehensively assessing the sustainable remediation performance of chlorinated aliphatic hydrocarbons polluted groundwater in practical applications. [Display omitted] • mZVI particles size and dosage influenced sustainable remediation performance. • 30 μm mZVI-AB had strong dosage-dependency of TCE removal and product selectivity. • MCA score aimed to decide best mZVI-AB system to achieve sustainable remediation. • 15 g/L, 30 μm mZVI/AB system exhibited a better sustainability. [ABSTRACT FROM AUTHOR]