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Arsenic contamination of soils threatens the health of millions globally through accumulation in crops. While plants detoxify arsenic via phytochelatin (PC) complexation and efflux of arsenite from roots, arsenite efflux mechanisms are not fully understood. Here, white lupin (Lupinus albus) was grown in semi-hydroponics and exudation of glutathione (GSH) derivatives and PCs in response to arsenic was scrutinised using LC-MS/MS. Inhibiting synthesis of PC precursor GSH with L-buthionine sulfoximine (BSO) or ABC transporters with vanadate drastically reduced (>22%) GSH-derivative and PC2 exudation, but not PC3 exudation. This was accompanied by arsenic hypersensitivity in plants treated with BSO and moderate sensitivity with vanadate treatment. Investigating arsenic-phytochelatin (As-PC) complexation revealed two distinct As-PC complexes, As bound to GSH and PC2 (GS-As-PC2) and As bound to PC3 (As-PC3), in exudates of As-treated lupin. Vanadate inhibited As-PC exudation, while BSO inhibited both the synthesis and exudation of As-PC complexes. These results demonstrate a role of GSH-derivatives and PC exudation in lupin arsenic tolerance and reveal As-PC exudation as a new potential mechanism contributing to active arsenic efflux in plants. Overall, this study uncovers insight into rhizosphere arsenic detoxification with potential to help mitigate pollution and reduce arsenic accumulation in crops.

The phytoremediation efficiency of heavy metal‐contaminated saline soils is limited by low plant biomass and low accumulation of salt or heavy metals. Arbuscular mycorrhizal fungi (AMF) can directly promote plant growth or indirectly affect plant growth by regulating rhizosphere microbial communities; however, few studies have investigated the regulation of AMF on rhizosphere bacteria in heavy metal‐contaminated saline soils. This study investigated the effects of AMF (Funneliformis mosseae) on the growth and rhizosphere bacteria in Astragalus adsurgens Pall. and Stipa grandis P. Smirn. in cadmium (Cd)‐contaminated saline soils. The results revealed that F. mosseae improved the growth of the two grasses through distinct strategic mechanisms. In A. adsurgens, F. mosseae decreased shoot sodium ion (Na+) and Cd concentrations, increased Na+, Cd, and nutrient accumulations, enhanced the stability of the interaction network of the top 15 bacterial species with significant differences, and resulted in higher resistance of bacteria to external disturbances. F. mosseae increased the relative abundances of Paludibaculum, Pedomicrobium, and Aquicella, which positively correlated with biomass, Na+, and Cd accumulations. In S. grandis, F. mosseae promoted Na+, Cd, and nutrient accumulations and regulated interactions among the top 15 bacterial species with significant differences. Total nodes, total links, and average degree of the network increased, indicating a closer and more complex relationship between bacteria. F. mosseae increased the relative abundance of Devosia, Exiguobacterium, Pseudoxanthomonas, and Aliihoeflea, which positively correlated with biomass, Na+, and Cd accumulations. This study presented data to support plant‐mediated remediation of heavy metal‐contaminated saline soils using AMF symbiosis. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTSoil pollution with petroleum products is an urgent public health and environmental problem. Therefore, innovative solutions for cleaning soils contaminated with petroleum products are needed. One such solution is rhizodegradation, which is recognized as a sustainable and effective method of in situ soil remediation. Much of the previous research was done with monocultures, therefore the effects of different combinations of plants on the removal of petroleum products remain ambiguous. These studies evaluated three different herbaceous plant mixtures for the removal of total petroleum hydrocarbons (TPHs) from contaminated soil. Promising results were obtained. Selected herbaceous plant species and their mixtures can be successfully grown in contaminated soil at a contamination level of 6,817 mg/kg TPH DW according to the selected cultivation strategy. After applying a complex of biotechnology and agronomic solutions, the morphological and morphometric indicators revealed the good adaptability and tolerance of the selected herbaceous plants to growing in contaminated soil. After two years of pot testing application of different mixtures of herbaceous plants, the TPH (C6–C40) removal potential reached 85–90%.Given the need to expand the existing knowledge about sustainable methods of remediation of TPH-contaminated soil by applying biotechnology, it is important to further develop this area of scientific research. Although studies with single plant species are often available, information on the complex application of different plants for the treatment of THP-contaminated soils is lacking. The purpose of this research was to create the best mix of native herbaceous plants for the remediate of THP-contaminated soils. The compatibility of plants, tolerance to TPH pollutants, and ability to grow in poor soil were taken into account when preparing the mixtures. To reduce the stress of cultivated plants and ensure effective rhizodegradation, organic, mineral and biological additives were additionally utilized. The obtained results provide knowledge about the candidacy of selected plants in mixtures of herbaceous plants, their morphological and morphometric reactions to TPH-contaminated soil and their application to TPH rhizodegradation. [ABSTRACT FROM AUTHOR]

The article is devoted to topical issues of ensuring measures for restoration of agricultural land. The article notes that in recent years there has been a further deterioration in the quality of agricultural land. It is emphasized that the aggravation of the crisis phenomena regarding the current state of land is largely due to the hostilities in the country. The article analyses new types of soil degradation that have become widespread as a result of Russian military aggression. The article focuses on the fact that agricultural land is subject to the greatest degradation compared to other categories of land. It is established that there are preliminary and basic legal measures for land restoration. It is substantiated that preliminary land restoration measures include: application of mineral fertilisers, bio-fertilisers; washing of saline soils, their irrigation; planting of trees, sowing of herbaceous plants. Attention is paid to the introduction of crop rotation, which is an important measure for restoring agricultural land. The article also examines the responsibilities of land owners and users in the field of land restoration. Based on the results of the analysis of legislation, it is proved that the main organisational and legal measures for the restoration of agricultural land are as follows: reclamation of disturbed lands, conservation of degraded, low-productive and technogenically polluted lands, and land reclamation of lands with disturbed water regime. It is stated that the implementation of the above measures has received proper legal support. The author highlights the considerations that today land restoration measures are being implemented, which have not received proper legal support. The author examines the peculiarities of implementation of bioremediation (divided into two types: biostimulation and bioaugmentation), phytoremediation based on the use of properties of certain plant species, and de toxification of contaminated land. The author makes proposals for improving land legislation by legislating such land restoration measures as bioremediation, phytoremediation, land detoxificatio n and environmental requirements for their implementation. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThis review article explores the applications of Basella alba (Malabar spinach), a fast-growing vine plant known for its numerous health benefits, culinary uses, and potential in dye and oil production. Fluoride contamination in water poses a significant global health and environmental challenge, particularly in regions where natural and industrial activities lead to elevated fluoride levels. Among its varied applications, B. alba has shown significant promise in the phytoremediation of contaminants in both water and soil, owing to its hyper accumulating capacities. The plant has a transfer factor value of more than 1 which means that there is higher accumulation of contaminants in parts of the plant than in soil. The objective of this review is to assess the feasibility of B. alba in contributing to sustainable water management solutions for fluoride contamination, while offering a comprehensive evaluation of its environmental remediation potential. The article examines the biosorption capabilities of B. alba based on its established use in phytoremediation, offering insights into its suitability for addressing fluoride contamination in water. This article is organized into sections starting with an introduction, which brings explains the global challenge of fluoride, and different treatment techniques justifying why biosorption needs to be considered, cases of application of phytoremediation using B. Alba, and finally exploring the success factors for plants that have been applied for both biosorption and phytoremediation.This review article presents a novel exploration of Basella alba (Malabar spinach) as a biosorbent—a material capable of adsorbing contaminants from solutions—for fluoride removal from aqueous environments. While B. alba is well-known for its health benefits, culinary uses, and broad phytoremediation capabilities, its specific application in fluoride biosorption remains underexplored. This review addresses that gap by providing key findings on the plant’s fluoride adsorption capacity, the influence of pretreatment methods (such as chemical modification), and its efficiency under varying environmental conditions. Additionally, the paper explores the synergistic effects of combining biosorption with other treatment strategies, demonstrating B. alba’s potential for enhanced performance. By focusing on how B. alba can contribute to the pressing challenge of fluoride contamination in water—an issue that poses significant health risks in many regions—this research introduces a sustainable, low-cost, and eco-friendly approach to water purification. The findings contribute to advancing plant-based environmental remediation methods, offering a viable solution to fluoride pollution in areas where traditional treatments may be less accessible or affordable. [ABSTRACT FROM AUTHOR]

Aquaculture is important for food security and livelihoods, especially in the developing tropics. Many nutrients supplied by feed degrade water quality, waste resources and lead to nutrient loss. Halophytes have the potential to recover these nutrients from aquaculture effluents. Most studies have focused on temperate species, but there is a need for extractive species suitable for integration in tropical saline aquaculture. Sea purslane Sesuvium portulacastrum is a promising candidate providing biomass for human consumption with potential pharmaceutical applications, but to date, nutrient uptake has not been studied in this species. This study investigated the nutrient removal from milkfish wastewater by systems planted with S. portulacastrum in hydroponics versus planted in sand. Most nutrients were removed from the wastewater within 48 h. Phosphorus and nitrogen were most efficiently removed in treatments with plants and sand and on average lower in the hydroponic incubations. However, in hydroponic systems, plants assimilated 50.2% of the added labelled N with no significant difference in recovery after 48 h when 15NH4 or 15NO3 was added. The recovery of wastewater N into plant biomass was several-fold higher in hydroponics than in sand substrate. Integration of S. portulacastrum into aquaculture turns aquaculture effluents into a valuable resource. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTUrbanization and industrialization are exponentially deteriorating air quality, ecosystems, and human health. Phytoremediation is cost cost-effective, sustainable, and nature-based solution against air pollution. This study is designed to evaluate four species, Chlorophytum comosum, Rhapis excelsa, Spathiphyllum wallisii, and Ficus benjamina for their phytoremediation potential. The experimental setup consisted of a sealed chamber to place potted plants and equipment, it was also connected to the vehicular exhaust pipe. The Air Pollution Tolerance Index was highest for F. benjamina (12.19) and lowest for Rhapis excels (8.58). C. comosum has the highest VOC removal efficiency (90%, 0.172 ppm h−1). NOx remediation was highest by F. benjamina with 0.057 ppm h−1 (77%) removal efficiency. SOx and CO were remediated more efficiently by C. comosum, as 89%, (0.18 ppm h−1) and 80% (0.23 ppm h−1), respectively. R. excelsa reduced a higher concentration of NH3 (77%, 0.06 ppm h−1) compared to other species. R. excelsa and S. wallisii may serve as bio-indicator species. These findings provide a sustainable, natural, economical, and eco-friendly way to mitigate air pollution. F. benjamina and C. comosum are suitable species for urban landscapes, green spaces, urban plantations, and green walls to curb air pollutants due to traffic and industries.Based on the air pollution tolerance index, this study concludes that Rhapis excels (APTI = 8.58) can be used as a bio-indicator species for pollution monitoring and evaluation. Whereas, Ficus benjamina (APTI = 12.2) and Chlorophytum comosum (APTI = 10.3) are the best options for urban landscapes, green belts, or green walls for air pollution combat and mitigation. [ABSTRACT FROM AUTHOR]

The uptake of sodium selenite (Se(IV)) and sodium selenate (Se(VI)) from aqueous medium by Lemna minor L. and the influence of different Se concentrations on its growth, morphological and ultrastructural characteristics were studied. L. minor was grown at different concentrations (1, 3, 5 and 10 mg L−1) of Se(IV) and Se(IV). The Se(IV) concentration in the plant tissue ranged between 77.7 (± 4.3) to 453 (± 0) mg kg−1 DW. The Se(VI) concentration in plant tissues ranged between 117 (± 11) to 417 (± 2) mg kg−1 DW. The highest bioconcentration factor for Se(VI) was 127 (± 7) at 3 mg/L, with a Se removal efficiency of 44%. For Se(IV), the highest bioconcentration factor was 77.7 (± 4.3) at 1 mg L−1, which had a Se removal efficiency of 23%. Growth of L. minor was suppressed at 10 mg L−1 Se in both forms. The addition of Se promoted the formation of starch granules in L. minor which occupied a chloroplast area of 74% for Se(IV) and 77% for Se(VI). The efficient uptake of both Se forms by L. minor indicates the potential application of this species for phytoremediation of Se laden wastewaters and its use as an alternative feedstock in biofuel production. [ABSTRACT FROM AUTHOR]

Background: Although numerous endophytic bacteria have been isolated and characterized from cadmium (Cd) hyperaccumulators, the contribution and potential application of the core endophytic microbiomes on facilitating phytoremediation were still lack of intensive recognition. Therefore, a 2-year field sampling in different location were firstly conducted to identify the unique core microbiome in Cd hyperaccumulators, among which the representative cultivable bacteria of different genera were then selected to construct synthetic communities (SynComs). Finally, the effects and mechanisms of the optimized SynCom in regulating Cd accumulation in different ecotypes of Sedum alfredii were studied to declare the potential application of the bacterial agents based on core microbiome. Results: Through an innovative network analysis workflow, 97 core bacterial taxa unique to hyperaccumulator Sedum was identified based on a 2-year field 16S rRNA sequencing data. A SynCom comprising 13 selected strains belonging to 6 different genera was then constructed. Under the combined selection pressure of the plant and Cd contamination, Alcaligenes sp. exhibited antagonistic relationships with other genera and plant Cd concentration. Five representative strains of the other five genera were further conducted genome resequencing and developed six SynComs, whose effects on Cd phytoremediation were compared with single strains by hydroponic experiments. The results showed that SynCom-NS comprising four strains (including Leifsonia shinshuensis, Novosphingobium lindaniclasticum, Ochrobactrum anthropi, and Pseudomonas izuensis) had the greatest potential to enhance Cd phytoremediation. After inoculation with SynCom-NS, genes related to Cd transport, antioxidative defense, and phytohormone signaling pathways were significantly upregulated in both ecotypes of S. alfredii, so as to promote plant growth, Cd uptake, and translocation. Conclusion: In this study, we designed an innovative network analysis workflow to identify the core endophytic microbiome in hyperaccumulator. Based on the cultivable core bacteria, an optimized SynCom-NS was constructed and verified to have great potential in enhancing phytoremediation. This work not only provided a framework for identifying core microbiomes associated with specific features but also paved the way for the construction of functional synthetic communities derived from core microbiomes to develop high efficient agricultural agents. 5KavnCJpVp3k2g6uQCMsTe Video Abstract [ABSTRACT FROM AUTHOR]

Nickel (Ni) pollution in soil is a major environmental challenge to global food security necessitating its effective remediation. In this regard using plant growth promoting rhizobacteria (PGPR) and bioorganic fertilizers (BOF) to increase the effectiveness of Ni phytoextraction together with hyper-accumulator plants is an effective strategy. Thus, the aim of this study was to assess how BOF, alone or in combination with Bacillus sp. MN54 (herein after referred to as BS), promotes the growth and detoxifies Ni in Brassica juncea L. under both non-contaminated and Ni-contaminated soil conditions. The experimental design included both non-spiked and Ni-spiked soils (with two Ni concentrations: 50 and 100 mg kg−1), with the addition of BS and BOF at two different application rates (1% and 2%). Results showed that Ni negatively affected the growth attributes and yield of Brassica juncea but the integrated incorporation of BOF and BS significantly improved plant growth and physiological attributes. However, Ni stress increased antioxidant enzyme activities and triggered the production of reactive oxygen species in the plants. Likewise, the highest increases in Ni bioconcentration factor (19.9%, 72.83%, and 74.2%), Ni bioaccumulation concentration (30.6%, 327.4%, and 366.8%), and Ni translocation factor (22.2%, 82%, and 69%) were observed in soils supplemented with 2% BOF and BS under non-contaminated, 50 mg kg−1, and 100 mg kg−1 Ni-stressed conditions, respectively. The enhanced plant growth with BS and BOF under Ni stress suggested that both could efficiently promote Ni phytoextraction and simultaneously improve soil health in Ni-contaminated soil. This highlighted their potential as sustainable soil amendments for remediating Ni-contaminated soils, promoting resilient plant growth and supporting long-term ecosystem recovery. [ABSTRACT FROM AUTHOR]

Background: Phytoremediation is considered to have great development potential to deal with soil Cd contamination, and assisted measures are necessary to improve the efficiency of Cd extraction from soil by hyperaccumulator plants. Based on this, a pot experiment was conducted to determine the growth indices, physiological indices, Cd content of Solanum nigrum L. and soil bacterial community under single and combined application of earthworm and organic wastes [chili straw and spent mushroom substrate (SMS)]. Results: Pot experiments revealed that adding earthworms, chili straw, or SMS alone did not affect the growth of S. nigrum. However, the combination of earthworms + chili straw and earthworms + SMS, significantly increased the total dry weight of S. nigrum by 20.94% and 74.69% compared to the control. The chlorophyll content of S. nigrum in the treatment groups with earthworms, SMS, and earthworms + SMS was also significantly higher than that in the control. Meanwhile, adding earthworms and organic wastes also reduced the malondialdehyde content in the leaves of S. nigrum and increased the activity of superoxide dismutase and peroxidase. In addition, applying earthworm + chili straw and earthworm + SMS also increased the availability of Cd in the soil, promoted the absorption of Cd by S. nigrum, and significantly increased its total extraction amount of Cd by 41.55% and 92.83%, respectively. The diversity of soil bacterial communities increased when earthworms and organic wastes coexisted. Adding earthworms and organic wastes also increased the relative abundance of Verrucomicrobia at the phylum level and of Sphingomonas, Ohtaekwangia, Saccharibacteria_genera_incertae_sedis, and Aridibacter at the genus level in the soil. At the same time, this process reduces the relative abundance of Proteobacteria and Firmicutes at the phylum level and Devosia and Bacillus at the genus level. Conclusions: The combined application of earthworms and SMS enhanced phytoextraction of Cd-contaminated soil by S. nigrum. It also improved soil nutrient conditions and reduced external environmental stress on bacteria, increasing their diversity and restructuring the community structure, which was conducive to forming a good soil microecological environment. The results of this study can provide a scientific basis for the treatment of Cd contaminated soil, but field experiments need to be conducted for verification and optimization before practical application in the future. [ABSTRACT FROM AUTHOR]

Abstract\nSTATEMENT OF NOVELTYPhytoremediation of manganese (Mn)-contaminated water requires the selection of Mn-tolerant species. This study reports on physiological changes and Mn bioaccumulation in the aquatic macrophyte Pistia stratiotes cultivated under various MnCl2 concentrations: control, 80, 340, 600, 1000, 2000, and 4000 µM. Few visual symptoms of Mn toxicity, such as chlorosis, were observed after 10 days, especially in plants treated with 2000 and 4000 µM MnCl2. High Mn accumulation was recorded, with maximum values of 23,700 and 24,600 µg g−1 DW in the shoots and roots, respectively, at 4000 µM Mn, contrasting with 825.01 and 1587.53 µg g−1 DW in control plants. Cellular fractioning showed that Mn in shoots and roots was mainly associated with the cell wall, with approximately 90% of the Mn in roots detected in the apoplast. There were no significant changes in net CO2 assimilation or respiratory rates after 5 and 10 days of Mn exposure. These results demonstrate that P. stratiotes is a Mn hyperaccumulator species with excellent phytoremediation potential, as shown by its high bioaccumulation capacity and its ability to maintain photosynthetic efficiency under Mn stress.Our study proposes the use of Pistia stratiotes in the phytoremediation of aquatic environments contaminated by Mn. This species has a high bioaccumulation capacity with the capture of most of the Mn in the cell wall fraction, an efficient strategy to minimize damage to pigments and the photosynthetic rate in response to Mn stress. [ABSTRACT FROM AUTHOR]

Contamination of agricultural soil by heavy metals poses a significant threat to soil quality and crop yields. Using plants as a natural remediation approach attracts researchers' attention around the world. A 16-month pot experiment was conducted using Conocarpus erectus in a randomized complete block design. The growth, enzymatic activity, electrolyte leakage, and remediation potential were estimated under Cd nitrate]40 low (L), 60 medium (M), 80 high (H) mg/kg soil [and Pb nitrate]400 (L), 700 (M), 1,000 (H) mg/kg soil [applied individually and in combination. Conocarpus erectus demonstrated a good tolerance (over 70%) against lower and medium cadmium (Cd) and lead (Pb) levels and a medium resistance against high Cd and Pb levels, with a survival rate of 100% under all the treatments used. The most negative treatment on the growth traits and tolerance of C. erectus was (H) Cd and (H) Pb, which reduced plant height; chlorophyll index; dry weights of the leaves, stems, and roots; root length; and tolerance index of biomass and roots by 25.87%, 48.97%, 50.56%, 47.25%, 58.67%, 50.18%, 51.00%, and 50% in comparison to the respective control, consecutively. Relative to the control, all Cd and Pb applications increased polyphenol oxidase (PPO), peroxidase (POD), and catalase (CAT) activities, and the increment was parallel up to medium Cd and Pb levels and then decreased with their high levels but still higher than the control. Electrolyte leakage (EL) was upheaved by raising the levels of Cd and Pb, and it reached the maximum (52.79%) at the (H) Cd (H) Pb treatment. Cd and Pb in the leaves, stems, and roots were boosted by raising their levels in the treatments. Conocarpus erectus is considered a phytoextractor for the Cd levels used because the bioconcentration factor of the stem (BCFs) and the translocation factor (TF) of Cd were >1, and it is a suitable plant for Pb phytoextraction at (L) Pb, (M) Pb, and (M) Cd (M) Pb levels because its Pb BCFs and bioconcentration factor of the root (BCFr) were <1 and its Pb TF was >1. On the other hand, C. erectus is considered a phytostabilizator for Pb at (H) Pb, (L) Cd, (L) Pb, and (H) Cd (H) Pb levels because its Pb BCFs, BCFr, and TF were <1. [ABSTRACT FROM AUTHOR]

Phytoremediation is a strategy for the amelioration of soil heavy metal contamination that aligns with ecological sustainability principles. Among the spectrum of phytoremediation candidates, woody plants are considered particularly adept for their substantial biomass, profound root systems, and non-participation in the food chain. This study used Eucalyptus camaldulensis —a tree species characterized for its high biomass and rapid growth rate—to assess its growth and metal uptake in mining tailings. The results were as follows: exposure to heavy metals reduced the E. camaldulensis uptake of potassium (K), phosphorus (P), and calcium (Ca). Heavy metal stress negatively affected the biomass of E. camaldulensis. Lead (Pb) primarily accumulated in the roots, while cadmium (Cd) predominantly accumulated in the stems. The application of organic fertilizers bolstered the stress tolerance of E. camaldulensis , mitigating the adverse impacts of heavy metal stress. A synergistic effect occurred when organic fertilizers were combined with bacterial fertilizers. The plant's enrichment capacity for Cd and its tolerance to Pb was augmented through the concurrent application of bacterial and organic fertilizers. Collectively, the application of organic fertilizers improved the heavy metal tolerance of E. camaldulensis by enhancing the uptake of K, P, and Ca and elevating the content of glutathione peroxidase (GPX) and gibberellin acid (GA) in roots. These findings provided nascent groundwork for breeding E. camaldulensis with enhanced heavy metal tolerance. Moreover, this proved the potentiality of E. camaldulensis for the management of heavy metal-contaminated tailings and offers a promising avenue for future environmental restoration. [ABSTRACT FROM AUTHOR]

Heavy metals (HMs) contamination has gained much attention due to its high degree of toxicity for living organisms. Therefore, different techniques are underway to eradicate HMs from the environment. Among the biological techniques, phytoremediation is a suitable method, but owing to the slow rate and chance of HMs penetration into the food chain, alternative techniques are needed to reduce their phytotoxicity, and biochar is one of them. Due to the diverse characteristics, biochar immobilizes HMs in the soil by improving soil pH, ion exchange, electrostatic interactions, complexation, precipitation, surface adsorption, and microbial activation. Thereby, amendment of biochar in the HMs-contaminated soils reduces HMs toxicity to plants and limits their penetration into the food chain. In contrast, some biochars have also been studied to induce metal availability in soils and subsequently its uptake by plants. This dual role of biochar depends on the feedstock of biochar, incineration temperature, and the rate of application. Moreover, biochar treatments enhance plant growth under HMs stress by improving nutrient availability, water retention capacity, scavenging of reactive oxygen species, and photosynthetic efficiency. Owing to the beneficial characteristics of biochar in HMs-contaminated sites, the number of publications has tremendously increased. Additionally, the plant species and the types of HMs that have been tested frequently under biochar treatments in these articles have been studied. Overall, the current study would help in understanding the mechanisms of how biochar influences phytoremediation of HMs and improves plant growth in HMs-polluted soils and the current scenario of the available literature. [ABSTRACT FROM AUTHOR]

Heavy metals (HM) also known as potentially toxic elements (PTEs), are well-known environmental pollutants, among which lead (Pb) is a widespread and hazardous soil contaminant. Its removal from soil sediments is often difficult to achieve. In this study, in vitro experiments were conducted to investigate the bioaccumulation capability of Dianthus chinensis L. in solid and liquid Murashige and Skoog (MS) medium supplemented with varying concentrations (0, 10, 100, and 200 µM) of Pb as lead nitrate [Pb(NO3)2] for 30 days. The objectives of the study were to assess the efficiency of the selected plant as a bio-accumulator in the in vitro system and to obtain data on morphological, biochemical, and molecular changes during Pb salt-induced stress. Significant growth patterns of initial growth promotion up to 100 µM lead nitrate supplemented medium were observed, with maximum shoot length and biomass production along with remarkable lead bioaccumulation. Molecular studies on in vitro raised plantlets confirm the high degree of genetic uniformity (98.3%) of the selected plants after a considerable duration (30 days) of Pb exposure. Biochemical parameters revealed significant stress effects, including a 284% reduction in total chlorophyll content, altered carotenoid, and proline level during the study. The experiment revealed the high tolerance capacity of D. chinensis to Pb salt and its bioaccumulation potential (397.33 mg/kg). This increases the possible use of such an ornamental and floriculture plant as a prospective candidate for the efficient removal of soil Pb pollutants, as they can remediate soils, coupled with aesthetic and profitable outcomes for the growers. [ABSTRACT FROM AUTHOR]

Key Message: Transgenic Crambe abyssinica lines overexpressing γ-ECS significantly enhance tolerance to and accumulation of toxic metal(loid)s, improving phytoremediation potential and offering an effective solution for contaminated soil management. Phytoremediation is an attractive environmental-friendly technology to remove metal(loid)s from contaminated soils and water. However, tolerance to toxic metals in plants is a critical limiting factor. Transgenic Crambe abyssinica lines were developed that overexpress the bacterial γ-glutamylcysteine synthetase (γ-ECS) gene to increase the levels of non-protein thiol peptides such as γ-glutamylcysteine (γ-EC), glutathione (GSH), and phytochelatins (PCs) that mediate metal(loid)s detoxification. The present study investigated the effect of γ-ECS overexpression on the tolerance to and accumulation of toxic As, Cd, Pb, Hg, and Cr supplied individually or as a mixture of metals. Compared to wild-type plants, γ-ECS transgenics (γ-ECS1-8 and γ-ECS16-5) exhibited a significantly higher capacity to tolerate and accumulate these elements in aboveground tissues, i.e., 76–154% As, 200–254% Cd, 37–48% Hg, 26–69% Pb, and 39–46% Cr, when supplied individually. This is attributable to enhanced production of GSH (82–159% and 75–87%) and PC2 (27–33% and 37–65%) as compared to WT plants under AsV and Cd exposure, respectively. The levels of Cys and γ-EC were also increased by 56–67% and 450–794% in the overexpression lines compared to WT plants under non-stress conditions, respectively. This likely enhanced the metabolic pathway associated with GSH biosynthesis, leading to the ultimate synthesis of PCs, which detoxify toxic metal(loid)s through chelation. These findings demonstrate that γ-ECS overexpressing Crambe lines can be used for the enhanced phytoremediation of toxic metals and metalloids from contaminated soils. [ABSTRACT FROM AUTHOR]

This study aimed to examine the potential of soil amendment-assisted phytoremediation using ryegrass in reclaiming abandoned gold mine soil in southwestern Ghana, with a specific focus on the soil contamination hazards associated with metals and metalloids. A pot experiment lasting 60 days was carried out to assess the efficacy of soil amendments, such as compost, iron oxide, and poultry manure, in mitigating environmental hazards. Three soil contamination indices (soil contamination = CF, enrichment factor = ER, and pollution load index = PLI) were used to calculate the extent of soil contamination, enrichment, and pollution of the sites with Co, Hg, Ni, Mo, Se, Sb, and Pb. The findings show that Hg made the greatest contribution (with a maximum soil CF of 18.0) to the overall PLI, with a maximum value of 74.4. The sites were averagely and consequently enriched with toxic elements in the decreasing order: Ni (ER = 33.3) > Mo (20.5) > Sb (14.1) > Pb (11.0) > Hg (7.9) > Se (2.1). The bioaccumulation factor (BCF > 1) suggests that ryegrass has the ability to phytostabilize Co, Hg, Mo, and Ni. This means that the plant may store these elements in its roots, potentially decreasing their negative effects on the environment and human health. Ultimately, the addition of combined manure with iron oxides might have augmented the sequestration of these metals in the root. The elements may have accumulated through sorption on manure or Fe surfaces, dissolution from watering the plants in the pot, or mineralization of organic manure. Thus, ryegrass has shown potential for phytostabilisation of Co, Hg, Mo, and Ni when assisted with a combination of manure and iron oxides; and can consequently mitigate the environmental and human health impacts. NOVELTY OF WORK: Gold mining in Ghana has caused significant environmental damage and political unrest. Research on environmentally friendly solutions to land degradation is crucial for restoring degraded lands, preserving ecosystem integrity, restoring livelihoods, and protecting public health in gold mining hotspots. However, previous studies have often overemphasized the use of trees in improving soil quality. Other past studies have merely collected plant species for heavy metal analysis without concrete pots or field experiments. Ryegrass has only been limited to arsenic remediation, and its phytoremediation ability for other toxic elements like Co, Hg, Mo, Ni, Pb, Sb, and Se has not been investigated. This work reports for the first time the phytostabilisation ability of ryegrass for potentially toxic elements in a Ghanaian context. Consequently, recommendations are made for reclaiming gold-mine-affected sites while at the same time providing evidence for widening the choice of plant species available for restoring mine-derelict lands. Ultimately, the study fills the gap in phytoremediation research within the global scientific community and Ghana in particular. [ABSTRACT FROM AUTHOR]

Soil salinity is a significant abiotic stress and poses risks to environmental sustainability. Thus, the improvement of the time for recovering the salt-affect soil is crucial for the phytoextraction process using halophytes plants, especially regarding on nutritional management. We evaluated the responses of Atriplex nummularia Lindl. to nitrogen (N) and phosphorus (P) under different salinity levels. The treatments comprised doses of N (N1 = 80 kg ha−1) and P (P1 = 60 kg ha−1): (1) without N and P (N0P0) (control); (2) with N and without P (N1P0); (3) without N and with P (N0P1); and (4) with N and P (N1P1) and five levels of electrical conductivity from irrigation water: 0.08, 1.7, 4.8, 8.6, and 12.5 dS m−1. The. We evaluated dry biomass of leaves, stems, and roots 93 days after transplantation. We also assessed the leaf and osmotic water potential, the osmotic adjustment, and the nutrient contents (N, P, Na, and K). N application increased 22.3, 17.8, and 32.8% the leaf biomass, stem biomass, and osmotic adjustment, respectively; and consequently, boosts Na extraction in 27.8%. Thus, the time of the phytoextraction process can be improved with N fertilizer at a rate of 80 kg ha−1. NOVELTY STATEMENT: Very few studies have investigated the nutrient dynamics responses in Atriplex species in salt-affected soils; thus, this study represents a novelty. We tested the management of nitrogen (N) and phosphate (P) fertilizers to increase crop yield and optimize the phytoextraction process in salt-affected soils. We believe our results contribute to the improvement of the knowledge of this relevant topic, mainly in terms of the recovery of areas degraded by salinity. There is a paucity of studies associating salinity and nutritional management of soils worldwide. [ABSTRACT FROM AUTHOR]

Coal mining disperses heavy metals into the environment, necessitating the identification of metal-tolerant plants for ecosystem restoration. This study evaluated the phytoremediation potential of plant species in abandoned coal wastes in northern Iran. Pollution indices indicated moderate contamination of Cu, Ni, V, Zn, Pb, Cr, and As in coal wastes. The plants varied in their ability to accumulate and translocate these metals, with most showing efficient root-to-shoot translocation. Artemisia scoparia (41.06 mg.kg−1) and Capparis spinosa (42.48 mg.kg−1) were effective for Cu phytoextraction. Most species, notably Cynodon dactylon (3.4 mg.kg−1), showed promise for phytoextraction of Cr. Capparis spinosa (7.67 mg.kg−1) exhibited potential for Pb phytoextraction. Most plants, particularly Hordeum vulgare and Melica persica, were effective phytoextractors of Ni. Sylibum marianum accumulated V beyond phytotoxic levels. Chenopodium album and Glaucium fimbriligerum were identified as phytoextractors of Zn while Cynodon dactylon and Hordeum vulgare, accumulating >100 mg.kg−1 Zn in roots, showed potential for phytostabilization. Sylibum marianum and Glaucium fimbriligerum, acted as excluders for As. Kochia prostrata and Artemisia aucheri were excluders for Cu, Cr, Ni, and Pb. This study provided the role of multiple indigenous plants, including perennials and annuals with diverse life forms, in metal extraction and stabilization for sustainable coal waste management. [ABSTRACT FROM AUTHOR]

Vesicular sequestration is a potential strategy for enhancing plant tolerance to cadmium (Cd) and arsenic (As). In this study, the ectopic overexpression of yeast-derived ScSMF2 in Arabidopsis thaliana was found to enhance the accumulation and tolerance of Cd and As in transgenic plants. ScSMF2 was localized on vacuole membranes and formed puncta structures in plant cells when agro-infiltrated for transient expression. Transgenic Arabidopsis showed less retardation on root elongation and shoot weight and more accumulation of Cd, As (III) and As (V) when cultured on medium containing Cd or As. Overexpression of ScSMF2 promoted accumulation of Cd and arsenic in transgenic Arabidopsis, which were over twice higher than in WT plants when cultured in soil. This study provides insights into the mechanisms involved in the vesicular sequestration of heavy metals in plant and presents a potential strategy for enhancing the phytoremediation capacity of plants toward heavy metals. NOVELTY STATEMENT: Ectopic overexpression of the yeast Mn2+ transporter SMF2 in Arabidopsis thaliana substantially boosts the accumulation and tolerance to Cd and As in plants. This augmentation is attributed to the enhanced efficacy of intracellular vesicle sequestration, thereby bolstering the capacity of plants to sequester and detoxify these toxic heavy metals. This investigation introduces a potential approach for cultivating plants with improved phytoremediation capabilities, thereby advancing eco-friendly and sustainable remediation initiatives against heavy metal pollution. [ABSTRACT FROM AUTHOR]

This article seeks to evaluate the scientific landscape of the phytoremediation of mine tailings through a series of bibliometric and scientometric techniques. Phytoremediation has emerged as a sustainable approach to remediate metal-contaminated mine waste areas. A scientometric analysis of 913 publications indexed in Web of Science from 1999 to 2023 was conducted using CiteSpace. The results reveal an expanding, interdisciplinary field with environmental sciences as the core category. Keyword analysis of 561 nodes and 2,825 links shows a focus on plant-metal interactions, microbial partnerships, bioavailability, and field validation. Co-citation analysis of 1,032 nodes and 2,944 links identifies seminal works on native species, plant-microbe interactions, and amendments. Temporal mapping of 15 co-citation clusters indicates a progression from early risk assessments and native plant inquiries to integrated biological systems, economic feasibility, and sustainability considerations. Recent trends emphasize multidimensional factors influencing adoption, such as plant-soil-microbe interactions, organic amendments, and field-scale performance evaluation. The findings demonstrate an intensifying translation of phytoremediation from scientific novelty to engineering practice. This quantitative and qualitative analysis of research trends aids in understanding the development of phytoremediation for mine tailings. The results provide valuable insights for researchers and practitioners in this evolving field. [ABSTRACT FROM AUTHOR]

This study proposes a model for phytoremediation coupling transport in soil and dynamic model using sunflower plants and 134Cs radionuclide. The model was validated by comparison with experimental measurements. The error value obtained, ranging from 0.00045–0.5268, is quite small, and the overall simulation data has approached the experiment. Factors influencing radionuclide concentration in different blocks include saturation point values, absorption rates of plant parts, soil dispersion coefficient, and velocity. The model is used to predict doses from ingesting sunflower seeds and estimates the soil-to-plant transfer factor. This new model is recommended for accurate assessment of environmental risks associated with radionuclides and for efficient decontamination. [ABSTRACT FROM AUTHOR]

Phytotoxic effects of herbicides have been reported on non-target plant species. This study was performed to investigate the growth of Napier grass cv. Pak Chong 1 in herbicide atrazine-contaminated soil; the effect of 1-naphthalene acetic acid, 6-benzyladenine and thidiazuron to stimulate the growth of grass grown in atrazine-contaminated soil; and to determine the remaining atrazine in the soil. The experiment was performed in a factorial completely randomized design with 2 × 10 factors. The first factor was atrazine concentration and the second factor was the application of plant growth regulator. The growth of the plants and atrazine remaining in the soil was analyzed at the end of the experiment (after 26 days). The results showed that Napier grass cv. Pak Chong 1 was tolerant to 6.8 mg/kg atrazine contamination in soil. The shoot growth and root growth of grass grown in atrazine-contaminated soil did not significantly differ from that grown in non-contaminated soil. Thidiazuron and 6-benzyladenine at 0.1 mg/l tended to increase the shoot dry weight of the grass grown in both atrazine-contaminated and non-contaminated soil. Additionally, 10 mg/l of thidiazuron and 1-naphthalene acetic acid tended to decrease the shoot growth of grass grown in both contaminated and non-contaminated soil. Moreover, decreases in atrazine were detected in soil planted with Napier grass cv. Pak Chong 1 by about 67.65% within 26 days. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Environmental pollution caused by urbanization, agricultural intensification, and industrialization has led to an increase in the disposal of toxic effluents in aquatic environments. Most ecosystems in the world receive a variety of toxic metals (TMs) that exceed the capacity of water bodies to absorb or recycle them, thereby threatening aquatic and human life. Physicochemical remediation methods encounter problems because of the high cost, labor input, and use of chemicals with long residence times that later add toxic by‐products. However, bioremediation techniques are a safe option for mitigating environmental pollution because of their high efficiency, cost‐effectiveness, non‐intrusiveness, eco‐friendliness, ease of application, and social acceptance. Submerged and free‐floating macrophytes were found to be more effective in the bioaccumulation of TMs than emergent macrophytes. Furthermore, most studies have suggested the use of macrophytes for the removal of TMs from water bodies; however, studies on the management of phytoremediated biomass are scarce. This review demonstrates the role of various macrophytes for the removal of TMs from water bodies and suggests techniques for the disposal and recycling of phytoremediated biomass with accumulated TMs. Further, the applications of genetically modified plants, nanotechnology, and native hyperaccumulators have been suggested as suitable candidates for greater efficiency of phytoremediation and appropriate management of TMs in the environment in the future. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Poor air quality in urban areas increases the exposure of individuals to air pollutants. Hence, it becomes mandatory to grow such plant species that have more potential to tolerate air pollution and can aid in its mitigation. Air pollution tolerance index (APTI) and anticipated performance index (API) are two indices that help in scientific evaluation of plant species before recommending them for plantation. In this study, six plant species from three educational institutions of Amritsar city were screened for their tolerance and performance against air pollution as well as for their capability to act as accumulators of nine metals viz., aluminium (Al), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn). On the basis of APTI, Cassia fistula (C. fistula) was categorized as a tolerant species while Alstonia scholaris (A. scholaris), Cascabela thevetia (C. thevetia), Monoon longifolium (M. longifolium), Pongamia pinnata (P. pinnata) and Syzygium cumini (S. cumini) were categorized as intermediately tolerant plant species. API results suggested that A. scholaris, C. fistula, M. longifolium, P. pinnata and S. cumini should be planted for air pollution mitigation. Geo-accumulation Index (Igeo) results showed that soil samples were moderately contaminated with three (Pb, Cu and Zn) metals. Bioaccumulation factor (BAF), for all metals among six plant species, was found to be less than one implying that these plants were absorbers of metals. Metal Accumulation Index (MAI) indicated that C. thevetia, C. fistula and P. pinnata exhibited relatively higher potential for metal accumulation. [ABSTRACT FROM AUTHOR]

Mercury is classified as one of the world's most toxic and dangerous pollutants as it tends to bioaccumulate and biomagnify within the trophic chain and is persistent. Various approaches are available to remediate Hg-affected sites including phytoremediation, which includes the use of plants to clean up contaminated environments. The phytoremediation of mercury contamination is attracting increasing attention because of its advantages: it is environmentally friendly, inexpensive, simple, and can improve soil fertility. In this report, VOSviewer (version 1.6.1) and Bibliometrix (version 4.16) software were used to analyze 457 and 697 documents published from 2000 to 2023, retrieved from the databases WoS and Scopus, respectively. China, India, the United States, and Spain were the top four most productive countries. The largest topic area was environmental sciences, and the Chinese Academy of Sciences was the organization that contributed the most to the overall number of publications. The keywords with the highest frequency excluding phytoremediation and mercury in WoS were heavy metals, accumulation, cadmium, soils, and phytoextraction. In Scopus, the most frequent keywords were bioremediation, heavy metals, soil pollution, bioaccumulation, biodegradation, and environmental. From the above analysis, we concluded that future research should focus on (1) finding native plants, (2) genetic engineering applications, (3) increasing remediation ability through assisted phytoremediation, and (4) the detoxification mechanism of mercury. This study provides insights into trending themes and serves as a reference for future research. [ABSTRACT FROM AUTHOR]

Phytoremediation of oil pollution using free-floating aquatic plants is a promising method for water body cleaning. In this study, the influence of Eichhornia crassipes and Pistia stratiotes on the degradation of oil pollution was investigated. The loss of oil alkanes and the rheological characteristics of water were evaluated, and an analysis of the emerging rhizospheric microbial communities was carried out using high-throughput sequencing. The presence of E. crassipes and P. stratiotes plants in oil-contaminated tanks had no effect on the degradation of oil alkanes. However, the presence of plants promoted the development of rhizospheric bacteria capable of growing in oil-contaminated environments. Alpha diversity of microbial communities in oil-contaminated samples was higher in the presence of plants. Additionally, plants significantly reduced the water/oil interfacial tension, which facilitated the availability of hydrocarbons for biodegradation. A difference was noted in the microbiome between E. crassipes and P. stratiotes. Changes in the composition of microbial communities highlight the potential of E. crassipes and P. stratiotes as rhizospheric hosts for microorganisms in the phytoremediation of water bodies. [ABSTRACT FROM AUTHOR]

Diesel power plants produce wastewater containing heavy metals. This study focused on analyzing the role of mangroves around the site. The results showed that Cu metal concentrations in sediments ranged from 10.01-17.76 mg/kg and Cr ranged from 13.06-20.34 mg/kg, and Cu and Cr metal concentrations in Avicennia sp. mangrove were 25.04-42.05 mg/kg; 11.78-28.21 mg/kg, respectively, and showed bioaccumulation and translocation abilities of Cu and Cr of 2.34-2.5 (BCF > 1) and 0.6-0.69 (TF < 1); 0.9-1.39 (BCF < 1) and 0.4-0.53 (TF < 1), while in mangrove Rhizophora sp., namely 13.51-29.24 mg/kg; 21.52-58.38 mg/kg, and showed bioaccumulation and translocation abilities of Cu and Cr, respectively, 1.35-1.64 (BCF > 1) and 0.61-0.74 (TF < 1); 1.65-2.87 (BCF > 1) and 0.62-0.84 (TF < 1). BCF > 1 indicates that mangroves are accumulators, and BCF < 1 is an excluder. TF value < 1 indicates that mangroves are phytostabilisers. This research can be a reference for diesel power plant companies to plant mangroves Avicennia sp. and Rhizophora sp. around the source of wastewater outlets. In addition to absorbing CO2 emissions in the environment, they can also absorb heavy metals derived from diesel processing. [ABSTRACT FROM AUTHOR]

The current study used to prove the efficiency of Tecoma stans to sulfur dioxide gas (SO2) was at a concentration of 10 mg·m-3 which is equal to 3.82 ppm for the period from summer exposure (May - June 2023) to reduce SO2 thus reduce some gaseous pollutants that cause global warming and some air pollutants and know the effect of seasonal conditions to mitigate these pollutants. The physiological changes of the three replicates of study plant were observed through equal time periods daily for a period of seven days covered with polyethylene under controlled conditions represented by a greenhouse. The process was repeated three times between the three exposures provide rest periods for the plant for a week. During summer exposure, it was found that the concentration of flavonoids was significantly increased as compare to control (5.222 ± 0.27 mg/100 ml of extract) from 6.58 ± 0.43 to 6.24 ± 0.31 mg/100 ml of extract, but this concentration was increased after the third exposure into to 6.99 ± 0.29 mg/100 ml of extract. There was decrease in Tannins concentration after the second exposure (with concentration 1.5 ± 0.05 to 0.72 ± 0.01 µl/ml)), but this concentration was returned increased significantly to 1.36 ± 0.01 µl/ml) after the third exposure to SO2. Also in The enzyme activities for peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) demonstrated varied responses to SO2 exposure, and T. stans showing distinct patterns of enzyme activation. The effect of POD and CAT increased in plants which exposure into SO2, whereas CAT play important role in inhibition of ROS. [ABSTRACT FROM AUTHOR]

The urgency of protecting ecosystems and their recovery from contamination has been highlighted in several recent European strategies because Europe's biodiversity and landscapes are declining rapidly due to different human pressures. Despite the existence of EU and national laws addressing environmental contamination, practical procedures are often missing. For example, competent authorities must deal promptly and effectively with environmental accidents, noncompliance, and criminal offenses but relevant tools that facilitate these processes are often lacking. For example, thorough planning is crucial for effective investigation and assessment to improve environmental damage assessments in line with the European Environmental Liability Directive (ELD, 2004/35/EC). With regard to soils, a specific European legislation for their protection, the European Soil Monitoring Law, is currently being developed. However, it is crucial that this law bridges the gaps between existing chemical regulations and that it aligns with current European strategies for environmental protection and sustainability. Continuous feedback of soil monitoring results to regulatory frameworks will be essential. This feedback loop ensures that chemical regulations are relevant and effective in protecting soil health. In this context, development and sharing of effective and practical procedures for recovering ecosystems from contamination are crucial. This was the case at the RemTech Europe meeting, which was held online and onsite in Ferrara, Italy, in September 2022. The discussion covered all aspects of environmental contaminants. It ranged from the basic understanding of these contaminants to the various types that pose a threat to organisms, studies of their environmental fate, detection methods, and sustainable practices for contaminant management. The special series dedicated to RemTech Europe 2022 is particularly relevant to these purposes and resulted in six articles that were selected from oral presentations. The articles emphasize the need for integrated approaches to risk management and remediation to address the problems of soil, sediment, and groundwater contamination. Integr Environ Assess Manag 2024;20:1982–1986. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: The RemTech Europe community is an important forum for discussing best practices, experiences, scientific and technological research results, and methodological approaches.A special emphasis is placed on phytoremediation as an inexpensive and environmentally friendly tool for recovering contaminated soils, as applied using conceptual models.Practical guidelines and operating procedures to monitor the environmental impact of human activities are reported here to guide the recovery of polluted sites.The European experience in recovering from contamination can help other countries, in addition to learning from past mistakes. [ABSTRACT FROM AUTHOR]

Soil contamination is a significant environmental issue that poses a threat to human health and the ecosystems. Conventional remediation techniques, such as excavation and landfilling, are often expensive, disruptive, and unsustainable. As a result, there has been growing interest in developing sustainable remediation strategies that are cost‐effective, environmentally friendly, and socially acceptable. One such solution is phytoextraction: a nature‐based approach that uses the abilities of hyperaccumulator plants to uptake and accumulate metals and metalloids (potentially toxic elements [PTE]) without signs of toxicity. Once harvested, plant biomass can be treated to reduce its volume and weight by combustion, thus obtaining bioenergy, and the ashes can be used for the recovery of metals or in the construction industry. However, phytoextraction has shown variable effectiveness due to soil conditions and plant species specificity, which has led researchers to develop additional approaches known as assisted phytoextraction to enhance its success. Assisted phytoextraction is a remediation strategy based on modifying certain plant traits or using different materials to increase metal uptake or bioavailability. This review article provides a practical and up‐to‐date overview of established strategies and the latest scientific advancements in assisted phytoextraction. Our focus is on improving plant performance and optimizing the uptake, tolerance, and accumulation of PTE, as well as the accessibility of these contaminants. While we highlight the advantages of using hyperaccumulator plants for assisted phytoextraction, we also address the challenges and limitations associated with this approach. Factors such as soil pH, nutrient availability, and the presence of other contaminants can affect its efficiency. Furthermore, the real‐world challenges of implementing phytoextraction on a large scale are discussed and strategies to modify plant traits for successful phytoremediation are presented. By exploring established strategies and the latest scientific developments in assisted phytoextraction, this review provides valuable guidance for optimizing a sustainable, nature‐based technology. Integr Environ Assess Manag 2024;20:2003–2022. © 2024 SETAC Key Points: Assisted phytoextraction is a promising technique for the remediation of soils contaminated with potentially toxic elements.Improving plant performance and promoting the solubility of potentially toxic elements are two critical steps for increasing the efficiency of phytoextraction.To be considered a nature‐based solution, assisted phytoextraction should be integrated into a phytomanagement strategy, to ensure not only environmental but also economic and social benefits.There is a need for further insights into the key factors that control plant–bacteria and plant–fungi symbiosis involving native species to enhance phytoextraction. [ABSTRACT FROM AUTHOR]

With the increasingly serious problem of air pollution, although plants have a certain air purification function, their inherent purification ability and efficiency are generally low. This study innovatively combined immobilized enzyme MIL-88B (Fe)/HRP with three plant species to construct a novel air purification system. The aim is to enhance the purification rate of plants for benzene. By evaluating the purification effects of the combined system on benzene under different initial concentrations and exposure times, the study also analyzes the impact of immobilized enzymes on the antioxidant system of plants. The results indicate that after introducing MIL-88B (Fe)/HRP into the rhizosphere solution of plants, the transport rates of Spathiphyllum kochii, Epipremnum aureum, and Chlorophytum comosum in the combined system significantly increased, by 294, 418, and 334 times, respectively, compared to the single plant system. The maximum purification rates were 3.87, 3.18, and 1.42 times higher than the single systems. Immobilized enzymes increased the activity of POD enzymes in plants, enhancing plant tolerance to benzene. The effective degradation of benzene in the rhizosphere solution by MIL-88B (Fe)/HRP has led to the creation of a benzene concentration gradient across multiple interfaces of the air-leaf-root-rhizosphere solution, facilitating the unidirectional transport of benzene within the plant body. This process enhances the plant's purification ability towards benzene. This work offers novel concepts and a theoretical foundation for environmental pollution control, in addition to broadening the application boundaries of phytoremediation technology. [ABSTRACT FROM AUTHOR]

Anthropogenic activities, encompassing vast agricultural and industrial operations around the world, exert substantial pressure on the environment, culminating in profound ecological impacts. These activities exacerbate soil contamination problems with pollutants such as mercury (Hg) and chlorpyrifos (CPF) that are notable for their widespread presence and detrimental effects. The objective of this study is to evaluate the phytoremediation potential of Phaseolus vulgaris L., augmented with various combinations of biochar, mycorrhizal, and compost amendments, as a sustainable alternative for the remediation of soils contaminated with Hg and CPF. For this purpose, soil from a mining area with mercury contamination has been taken, to which CPF has been added in different concentrations. Then, previously germinated Phaseolus vulgaris L. seedlings with an average height of 10 cm were planted. Electrical conductivity, pH, organic matter, CPF, and Hg, as well as seedling growth parameters, have been evaluated to determine the processes of absorption of soil contaminants into the plant. A combination of biochar with mycorrhiza has been found to be an optimal choice for CPF and Hg remediation. However, all amendments have proven to be efficient in the remediation processes of the tested contaminants. [ABSTRACT FROM AUTHOR]

The risk of arsenic contamination is rising globally, and it has negative impacts on the physiological processes and growth of plants. Metal removal from contaminated soils can be accomplished affordably and effectively with plant growth promoting rhizobacteria (PGPR)-based microbial management. From this angle, this research evaluated the mitigation of arsenic toxicity using the bacteria isolated from contaminated site, Mettur, Salem district, South India. The newly isolated bacterial strain was screened for plant growth promotion potential and arsenic tolerance such as (100 ppm, 250 ppm, 500 ppm, 800 ppm and 1200 ppm). The metal tolerant rhizobacteria was identified using 16S rRNA gene sequence analysis as Pseudomonas alcaliphila strain PAS1 (GenBank accession number: OQ804624). Pigeon pea (Cajanus cajan) plants were used in pot culture experiments with varying concentrations of arsenic, (5 ppm, 10 ppm and 25 ppm) both with and without bacterial culture, for a period of 45 days. At the concentration of 25 ppm after the application of PAS1 enhanced the plant growth, protein and carbohydrate by 35.69%, 18.31% respectively. Interestingly, P. alcaliphila strain PAS1 significantly reduced the stress-induced elevated levels of proline, flavonoid, phenol and antioxidant enzyme in pigeon pea plants was 40%, 31.11%, 27.80% and 20.12%, respectively. Consequently, PAS1 may significantly reduce the adverse effects that arsenic causes to plant development in acidic soils, improve plant uptake of nutrients, and increase plant production. The findings of this study reveal that P. alcaliphila PAS1 is intrinsic for phytoremediation by reducing arsenic accumulation in the root and shoot. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe industrial past of most regions in Lorraine and the intensification of activities on soils has increased the number of polluted sites. To rehabilitate these areas, several methods can be employed. In this study, co-culture of Miscanthus x giganteus and Pelargonium x hortorum was used to clean up a soil mainly contaminated by metallic elements including lead. The use of ornamental plants has been little studied, even if these species can be used to rehabilitate a site while improving its esthetics. At the end of the experiment, Pb concentrations were measured in the soil and plants. Furthermore, phytohormones were also measured to evaluate the defense mechanisms of the plants in front of pollutants. The results showed a reduction in Pb concentrations following the phytoremediation process implemented and that PxH was able to extract Pb from the soil. Results showed that co-culture was not beneficial to the development of MxG. Concerning the molecules synthesized by the plants under stress conditions, only salicin was found in MxG roots and aerial parts in particular for plants grown in individual culture. According to the results obtained, it seems that MxG is able to make compromises between the synthesis of protective molecules and its development.This study will provide a better understanding of plant defence mechanisms in a phytoremediation context. It will allow us to better understand how Miscanthus x giganteus reacts and develops when confronted with stress induced by soil pollution or co-cultivation with Pelargonium x hortorum by involving phytohormones such as salicin. Furthermore, this study will enable us to better manage industrial wasteland by choosing the most appropriate plants. [ABSTRACT FROM AUTHOR]

Heavy metal contamination is a serious global issue that threatens both environmental and human health. This study investigated the levels of 12 heavy metals in sediments, roots, stems, and leaves of Phragmites australis (common reed) from a river in Iran, using an inductively coupled plasma optical emission spectrometer (ICP-OES). The sediment metal concentration order was: Aluminum (Al) > Iron (Fe) > Manganese (Mn) > Zinc (Zn) > Magnesium (Mg) > Nickel (Ni) > Chromium (Cr) > Lead (Pb) > Copper (Cu) > Arsenic (As) > Vanadium (V) with Cadmium (Cd) below detection limit. Concentrations of As, Ni, Pb, and Zn in the sediments exceeded background values. According to sediment quality guidelines (SQGs), metal concentrations were between the threshold effect level (TEL) and the probable effect level (PEL), remaining below the severe effect level (SEL), except for Ni. Average metal concentrations in plant tissues were lower than in sediment samples, with roots showing higher levels of Cd, V, Cu, Pb, Zn, As, Al, Mg, and Fe than in the shoots, while leaves had higher Ni, Cr, and Mn. The bioaccumulation factor of less than 1 (except for V) indicates limited bioavailibility of these metals. [ABSTRACT FROM AUTHOR]

Soil amendments play a pivotal role in regulating rhizosphere microbial communities, which is essential for maintaining robust plant growth under adverse environmental conditions. However, the microbial mechanisms that underlie the impact of biochar on phytoremediation performance remain incompletely understood in the context of different application rates. Here, we compared the phytoremediation performance, rhizosphere microbial community characteristics, and microbial interactions in Salix psammophila across different biochar application rates (1%, 3%, 5%, and 7%) in Cd-contaminated soil. Applying 5% biochar increased plant biomass by 10.02%, root activity by 183.82%, and Cd accumulation by 13.65%. Lower biochar rates (1% and 3%) decreased Cd accumulation in plants by 21.89% and 42.05%, respectively, compared to the control. Rhizosphere soil properties and Cd content, except for nitrogen, showed a gradient change with increasing biochar application rates. This was accompanied by an elevation in the Chao1 index for the bacterial community, although the fungal community remained unaffected in terms of diversity and structure. Null-model analyses indicated that fungal community assembly was mainly driven by ecological drift, explaining its unresponsiveness to biochar application. Applying 1% biochar enhanced microbial network stability while reducing bacterial network complexity. Conversely, 3% biochar application resulted in the lowest microbial network stability. Biochar application, except 3%, reduced the proportion of bacteria-fungi associations, suggesting increased independence between two microbial kingdoms. Random forest and piecewise structural equation models revealed that phytoremediation performance is influenced by microbial network stability, complexity, and bacteria-fungi associations. Fungal complexity and stability, along with bacterial stability, were identified as key predictors of phytoremediation performance. Our findings reveal potential mechanisms by which biochar influences phytoremediation through altering microbial interactions. For long-term microbial stability and cost-effectiveness, a 1% biochar application is recommended for phytoremediation. Conversely, for rapid Cd accumulation in plants, a 5% biochar application is optimal. Highlights: • Bacterial rather than fungal communities were regulated by biochar application rate in soil. • Drift and homogeneous dispersal respectively dominated assembly of fungi and bacteria. • Biochar affects phytoremediation by regulating rhizosphere microbial interactions. • 1% of biochar is more appropriate considering the cost and the sustainability. [ABSTRACT FROM AUTHOR]

Background: Phytoremediation is affected by physical and chemical properties of the soil such as soil pH, moisture, and nutrient content. Soil pH is a key element influencing Cd bioavailability and can be easily adjusted in agricultural practices. The soil pH level may relate to the effectiveness of phytoremediation; however, this has not been extensively investigated. In the current study, we evaluated the effect of Cd contamination level (0.56 and 0.92 mg/kg) and soil pH (5, 6, and 7) on Cd accumulation and allocation in Artemisia argyi, a fast-growing perennial crop. Results: Our results indicated that higher soil Cd concentrations reduce A. argyi biomass, and the loss of the root mass was particularly significant. Higher soil pH decreased Cd content in stems and roots of A. argyi cultivated in moderately Cd-polluted soil, and increased Cd content in stems and roots of the plant grown in low Cd-polluted soil. Higher soil pH decreased the percentage of Cd distributed in the soluble fraction and cell walls and increased the percentage of Cd in the organelles of leaf cells for moderate soil Cd levels. The bioconcentration and translocation factor exceeded 4.0 and 1.0, respectively, across all tested treatments, indicating that A. argyi is a promising candidate for phytoremediation. Notably, the effects of soil pH on Cd accumulation and subcellular distribution in A. argyi differed between low and moderately Cd-contaminated soils. Conclusion: Adjustments to soil pH based on the degree of Cd contamination can enhance Cd extraction by A. argyi, thereby reducing the overall remediation cycle of cadmium-polluted paddy fields of South China. [ABSTRACT FROM AUTHOR]

Duckweeds (Spirodela polyrrhiza) are free-floating macrophytes that grow profusely in nutrient-rich waters. Under ideal conditions, they exhibit a rapid growth rate and can absorb a substantial amount of nutrients, macromolecules, and pollutants from bodies of water. Zinc oxide nanoparticles (ZnO NPs) synthesized from plant extracts, particularly under stress conditions, have opened new research avenues in the field of nanotechnology. Under salinity stress, the accumulation of flavonoids in duckweeds can affect the structure of ZnO NPs, helping researchers ascertain their antimicrobial role. In our study, we exposed mid-log phase duckweed monocultures to 75 mM NaCl in a full-strength Murashige and Skoog medium for 7 days, followed by a 15-day recovery period. We observed significant overexpression of superoxide and hydrogen peroxide as reactive oxygen species. As a result, chlorophyll and certain metabolites were produced in lesser amounts, while flavonoid and phenol content increased by 12% and 8%, respectively. This overproduction persisted up to 10 days into the recovery treatment period but dropped by 8% and 5%, respectively, by the 15th day. The flavonoid coating transformed the NPs into rosette clusters, which exhibited reduced antimicrobial activity against Aeromonas hydrophila, a Gram-negative, fish-pathogenic bacterium. Herein, we discuss potential mechanisms for the conformational transformation of ZnO NPs into finer dimensions in response to NaCl-induced oxidative stress in duckweed. In this study, the azo dye degradation capacity of salinity-treated plants increased as the flavonoid profile became enriched. Zinc oxide nanoparticles, both prior to and after salinity treatment, were found to be efficient in scavenging azo dye and mitigating its toxicity, as evidenced by improved germination, growth, and overall plant morphometry. [ABSTRACT FROM AUTHOR]

There is a common misconception that aquatic macrophytes face significant challenges in wetland-based sewage treatment systems. This study aims to correct this perception by focusing on the crucial morphophysiological adaptations of aquatic macrophytes that enable them to thrive in wetland-based sewage treatment systems, particularly under environmental stress. These adaptations are vital for improving the efficiency and resilience of wastewater treatment processes, offering sustainable solutions in the face of variable environmental conditions and complex contaminant mixtures. The review emphasizes the role of macrophytes as natural engineers, capable of enhancing pollutant removal and system stability through their unique structural and functional traits. By understanding these adaptations, the review aims to guide the optimization of wetland design and management, ultimately contributing to more sustainable and effective wastewater treatment practices. The findings underscore the importance of species selection and the integration of nature-based solutions in environmental management, advocating for policies that support the use of macrophytes in modern wastewater management. [ABSTRACT FROM AUTHOR]

Heavy metal (HM) contamination in soil poses a severe environmental threat, jeopardizing ecosystem health and potentially entering the food chain through plant uptake. Phytoremediation, a bioremediation technique utilizing plants to remove or immobilize contaminants, offers a sustainable and eco-friendly solution for HM remediation. This study investigated the interactive effects of arbuscular mycorrhizal fungi (AMF) and chelating agents (EDTA and DTPA) on the growth of maize (Zea mays L.) and alfalfa (Medicago sativa L.) cultivated in metal-contaminated soil and their impact on HM uptake by these plants. The findings revealed that AMF and chelating agents have complex interactive effects on plant growth and metal accumulation. Maize (Zea mays L.) shoot dry matter increased with AMF and chelating agents at lower concentrations. Both plants generally showed a significant (p ≤ 0.05) increase in shoot dry matter with amendments, with AMF × EDTA (10 mmol/kg) being the most effective for alfalfa. DTPA and EDTA generally reduced the DTPA-extractable metals in soil, suggesting potential for metal removal. However, the effects of AMF on metal availability were variable. Metal concentrations in maize (Zea mays L.) shoots increased with increasing DTPA and EDTA concentrations, while the effects of AMF were more complex. The alfalfa shoot metal content showed varied responses, with EDTA (5 mmol/kg) effectively reducing the metal uptake. In general, treatments involving chelating agents (DTPA and EDTA) tend to result in higher bioaccumulation factor (BF) values compared to the non-treated controls for most HMs in both plant species. Mycorrhizal fungi (AMF) treatment alone or in combination with chelating agents also showed that varied effects on HM uptake in both the alfalfa and maize treatments with chelating agents, especially at higher concentrations, generally promoted the greater translocation of HMs in both plant species. Both alfalfa and maize responded differently to treatments, with some treatments showing higher translocation factor (TF) values for certain HMs in one species compared to the other. Mycorrhizal fungi (AMF) treatment alone or in combination with chelating agents also showed varied effects on HM uptake and translocation in both alfalfa and maize. Further research is required to optimize remediation strategies that balance plant health and metal mobilization. [ABSTRACT FROM AUTHOR]

Rapid industrialization, mining, and other anthropogenic activities have poisoned our environment with heavy metals, negatively impacting all forms of life. Heavy metal pollution causes physiological and neurological disorders, as heavy metals are endocrine disrupters, carcinogenic, and teratogenic. Therefore, it becomes mandatory to address the challenge of heavy metal contamination on a global scale. Physical and chemical approaches have been employed for pollutant removal and detoxification, but these methods cannot be adopted universally due to high cost, labor intensiveness, and possible negative impact on natural microflora. Phytoremediation is one of the preferred and safest approaches for environmental management due to its high efficiency and low cost of investment. The plant can uptake the pollutants and heavy metals from water and soil through an intense root network via rhizofiltration and process via phytostabilization, phytovolatilization, and accumulation. At a cellular level, the phytoremediation process relies on natural mechanisms of plant cells, e.g., absorption, transpiration, intracellular storage, and accumulation to counter the detrimental effects of pollutants. It is widely accepted because of its novelty, low cost, and high efficiency; however, the process is comparatively slower. In addition, plants can store pollutants for a long time but again become a challenge at the end of the life cycle. The current review summarizes phytoremediation as a potential cure for heavy metal pollutants, released from natural as well as anthropogenic sources. It will provide insight into the advancement and evolution of advanced techniques like nanoremediation that can improve the rate of phytoremediation, along with making it sustainable, cost‐effective, and economically viable. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTIn this study, a composite of silver and titanium dioxide nanoparticles (AgNPs-TiO2NPs) was examined for its synergistic effects on phytostabilization of lead (Pb) and mitigation of toxicity in cowpea (Vigna unguiculata (L) Walp). Seeds of V. unguiculata were wetted with water, 0.05 and 0.1 mgL−1 Pb and 25 mgmL−1 each of AgNPs, TiO2NPs, and AgNPs-TiO2NPs. Root lengths of V. unguiculata were reduced by 25% and 44% at 0.05 and 0.1 mgL−1 Pb, respectively, while shoot lengths were reduced by 2% and 7%. In V. unguiculata, AgNPs and TiO2NPs significantly improved physiological indicators and mitigated Pb effects, with TiO2NPs modulating physiological parameters more effectively than AgNPs. The composite (AgNPs-TiO2NPs) synergistically regulated V. unguiculata physiology better than individual nanoparticles. Compared to individual AgNPs and TiO2NPs, the composite (AgNPs-TiO2NPs) synergistically increased antioxidant activity by 12% and 9%, and carotenoid contents by 88%. Additionally, AgNPs-TiO2NPs effectively reduced malondialdehyde levels by 29%, thereby mitigating the effects of Pb on V. unguiculata better than individual nanoparticles. AgNPs-TiO2NPs enhanced Pb immobilization by 57%, reducing its translocation from soil to shoots compared to V. unguiculata wetted with water. The bioconcentration and translocation factors of Pb indicate that phytostabilization was most effective when the composite was used.A synergetic interaction between silver nanoparticles and titanium dioxide nanoparticles (AgNPs-TiO2NPs) was investigated in this study for their capability to promote phytostabilization of Pb pollution in cowpea (Vigna unguiculata (L) Walp). This study shows a notable improvement in plant physiological indices, antioxidant activity, and the immobilization of Pb when AgNPs-TiO2NPs are employed in synergy, as opposed to using them separately. Additionally, the study demonstrates how nanoparticles can synergize to enhance phytostabilization, offering promising prospects for sustainable phytoremediation strategies in the environment. [ABSTRACT FROM AUTHOR]

Treatment wetlands have been used for decades to treat wastewaters with low organic strength, but little information is available on the treatment of wastewaters with high organic strength. The objective of this study was to evaluate the efficiency of a vertical flow wetland in the primary treatment of synthetic wastewater with medium organic strength (1976 mg COD/L). Alternatives in the reuse of the resulting treated wastewater were also considered. The wetland consisted of several layers of sand and gravel of different granulometry and was planted with the helophyte Eryngium horridum, a species rarely used in treatment wetlands. The wetland was fed with synthetic wastewater by a single feed pulse, with a hydraulic retention time of 24 h. The treatment removed 81% of TSS and 70% of COD. The concentrations of ammonium nitrogen and soluble reactive phosphorus increased due to partial mineralization of organic matter. Total phosphorus and total nitrogen removal were 28% and 5%, respectively. Wastewater suitability for reuse in irrigation increased after treatment. However, a later stage is recommended to further reduce COD and nutrient concentration and disinfect the water. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe soil pollution caused with accretion of pollutant elements like lead (Pb) is the major environmental concern nowadays. Phytoremediation of contaminated soils using Brassica cultivars that act as hyperaccumulator plants for Pb emerges as an important technique for decontamination of Pb spiked soils. Therefore, pot study was carried out to compare the efficiency of three Brassica cultivars and select the most efficient cultivar for phytoremediation of Pb spiked soils. The experimental soil was contaminated with Pb applied @ 0, 125, 250, 500, 750, and 1,000 mg kg−1 soil. Our outcomes reflected that increased rates of Pb pollution in soil from 125 to 1,000 mg kg−1 soil resulted in decline of yield but enhanced the Pb acquisition of all Brassica cultivars. Comparison of cultivars indicated the highest biomass production (16.7 g pot−1), Pb acquisition (4,011.7 μg pot−1), contamination indices i.e., tolerance index (70.6), and bioaccumulation coefficient (17.03) by Brassica juncea produced thereby proving it as the most efficient cultivar for phytoremediation of Pb spiked soil.Consumption of crops raised in Pb spiked soil resulted in impaired health of human beings through its entrance into the food chain. Choice of techniques for decontamination of Pb polluted soils poses a great challenge worldwide. Among different techniques phytoremediation i.e., use of hyper accumulator crops is the most economical and ecological approach for the decontamination of Pb spiked soils. Therefore, this study was conducted for evaluating the comparative efficacy of three Brassica cultivars for their Pb accumulation potential and pollution indices and select the most efficient cultivar for phytoremediation of Pb spiked soils. [ABSTRACT FROM AUTHOR]

Phytoremediation is a strategy for the amelioration of soil heavy metal contamination that aligns with ecological sustainability principles. Among the spectrum of phytoremediation candidates, woody plants are considered particularly adept for their substantial biomass, profound root systems, and non-participation in the food chain. This study used Eucalyptus camaldulensis--a tree species characterized for its high biomass and rapid growth rate--to assess its growth and metal uptake in mining tailings. The results were as follows: exposure to heavy metals reduced the E. camaldulensis uptake of potassium (K), phosphorus (P), and calcium (Ca). Heavy metal stress negatively affected the biomass of E. camaldulensis. Lead (Pb) primarily accumulated in the roots, while cadmium (Cd) predominantly accumulated in the stems. The application of organic fertilizers bolstered the stress tolerance of E. camaldulensis, mitigating the adverse impacts of heavy metal stress. A synergistic effect occurred when organic fertilizers were combined with bacterial fertilizers. The plant's enrichment capacity for Cd and its tolerance to Pb was augmented through the concurrent application of bacterial and organic fertilizers. Collectively, the application of organic fertilizers improved the heavy metal tolerance of E. camaldulensis by enhancing the uptake of K, P, and Ca and elevating the content of glutathione peroxidase (GPX) and gibberellin acid (GA) in roots. These findings provided nascent groundwork for breeding E. camaldulensis with enhanced heavy metal tolerance. Moreover, this proved the potentiality of E. camaldulensis for the management of heavy metal-contaminated tailings and offers a promising avenue for future environmental restoration. [ABSTRACT FROM AUTHOR]