Search Results (59)

Sudden tailings dam breaches trigger large-scale heavy metal compound pollution in coupled surface water–groundwater systems, requiring systematic full-cycle ecological damage quantification tools applicable to diverse contamination types. This study constructs an integrated full-cycle ecological damage assessment framework for sudden water pollution accidents, integrating three core modules: multi-model pollutant migration prediction, multi-scale aquatic biological damage diagnosis, and three-dimensional ecological-economic loss accounting. The framework adopts a modular design that can potentially accommodate heavy metals (Cd, Cr, As, Pb) and organic pollutants such as polycyclic aromatic hydrocarbons (PAHs), with standardized molecular, individual, and population-level biological endpoints and corresponding pollutant dose–response templates reserved as reference calculation modules. However, applicability beyond this case has not been validated and requires case-specific calibration. To verify the operability and accuracy of the proposed integrated system, a typical tailings dam leakage incident dominated by hexavalent chromium (Cr(VI)) and arsenic (As) pollution was selected as the practical validation case; all field monitoring, pollutant simulation, and final economic loss quantification in this case exclusively rely on on-site measured Cr(VI) and As data, while Cd and PAH-related biological response curves and remediation cost formulas retained in the manuscript only serve as illustrative universal template components of the framework rather than case-measured results. For the Cr(VI)/As pollution case, the advection–diffusion model simulation revealed that the Cr(VI) contamination plume horizontally spread 250 m within 48 h and extended to 560 m after seven days, and anaerobic groundwater environments drove the transformation of toxic mobile trivalent arsenic (As(III)) from primary pentavalent arsenic. The calibrated SWAT model achieved Nash–Sutcliffe efficiency (NSE) coefficients of 0.75 for dissolved Cr(VI) and 0.68 for particulate As. The graph theory-based rapid prediction model cut computation duration down to minutes; when validated against independent field monitoring data, it yielded an average relative error of 14.2%, and its consistency with the SWAT model reached 10.5% relative deviation, satisfying the accuracy requirement for emergency early warning. Field biological monitoring demonstrated substantial ecological impairment: metallothionein (MT) expression in fish tissues was markedly elevated (the reported 6.2-fold induction value derives from standard Cd exposure template tests within the framework, with analogous MT upregulation also observed for field Cr(VI)/As co-stress), and benthic community Shannon diversity declined by over 50% in polluted river reaches. The standardized Ecological Damage Index (EDI) of the case was calculated as 480.2, indicating severe aquatic ecosystem damage, with total comprehensive ecological and economic losses reaching 17.25 million CNY. This study innovatively couples high-precision physical transport models with fast emergency prediction algorithms and establishes a complete multi-tier biological indicator chain linking molecular biomarkers to community integrity metrics; the three-dimensional loss accounting system integrating ecosystem service impairment, restoration expenditure, and post-pollution recovery loss realizes closed-loop full-cycle damage evaluation. The proposed framework, demonstrated for Cr(VI) and As pollution, has a modular design that may potentially be extended to other pollutants such as Cd and PAHs by adjusting model parameters, providing a quantitative reference for emergency disposal, pollution remediation, and ecological compensation of water contamination accidents, although further validation across different pollutants and hydrological settings is required. Full article

Undergraduate Water Quality Engineering courses rely on verification experiments lacking real engineering scenarios, limiting undergraduate participants’ comprehensive problem-solving skills. To remedy this issue, this study constructs an inquiry-oriented experiment using carbon-coated nano-calcium carbonate (C@CaCO₃) to enhance biological nitrification for digested wastewater with low alkalinity and high ammonia. It involves wastewater characterization, sequencing batch reactor (SBR) operation, quantification of chemical oxygen demand (COD), ammonium nitrogen (NH₄⁺-N) removal, mechanism discussion on alkalinity slow release and microbial carrier role of C@CaCO₃, and high-throughput analysis of microbial communities. Experimental results show that C@CaCO₃ increases NH₄⁺-N removal by 94.5 ± 4.8% in low-alkalinity water, while COD removal improves from 5.7 ± 3.0% to 29.5 ± 5.2%. These findings demonstrate that C@CaCO₃ effectively mitigates alkalinity limitation, facilitates microbial attachment, and promotes functional microbe enrichment, offering a practical solution for sustainable nitrogen management in nutrient-rich waste streams. Pedagogically, the case links water-quality monitoring, reactor control, and solid-waste resource recovery, enabling undergraduate participants to trace the full engineering workflow problem identification through quantitative design, operation, and mechanistic interpretation. Post-laboratory surveys and performance assessments indicate significant gains in experimental competence, data-analysis skills, and engineering judgment. By embedding a real-world, low-alkalinity wastewater challenge within the curriculum, the module advances sustainable water-resource management education and provides a replicable model for reforming laboratory teaching in Water Quality Engineering and related environmental-engineering courses. Full article

With rapid urbanization, the generation of municipal solid waste is growing, placing ever-increasing pressure on cities to close, remediate and repurpose landfill sites in environmentally sustainable and climate-adaptive ways. Traditional landfill final covers such as compacted clay and geosynthetic systems are intended to limit infiltration; yet their conceptual designs often fail in performance longevity due to effects such as desiccation, settlement, root intrusion, freeze–thaw cycling and extreme rainfall. Phytocapping, or evapotranspiration/store-and-release cover technology is the use of vegetated soil profiles to provide storage for percolating rainfall, return water to the atmosphere through evapotranspiration and support biologically mediated oxidation of methane. Phytocapping is a green-inclusive nature-based climate adaptation strategy for urban landfill closure. This study explores hydrological performance, methane mitigation, ecological co-benefits, economic feasibility, climate sensitivity, monitoring requirements and regulatory barriers linked to phytocapping systems. Field evidence is strongest in Australia and the United States, especially through ACAP- and A-ACAP-style programs, while evidence from humid tropical, monsoon, freeze–thaw and low-resource urban contexts is comparatively lacking. As reported in published studies, well-designed phytocaps can result in reduced percolation compared to traditional clay caps. Reported publications also mention considerable construction-cost savings, depending on site conditions and design assumptions. Methane-related outcomes vary by measurement method and site context, with studies reporting surface flux reductions, methane oxidation and landfill gas attenuation as distinct performance indicators. These advantages are counter-balanced by design uncertainties that vary from site to site, limited long-term monitoring data, climate transferability concerns, and regulatory systems still firmly anchored in prescriptive low-permeability barriers. This review proposes a policy-oriented analytical framework that bridges the gap between technical performance evidence, urban co-benefits, staged monitoring and performance-based landfill closure regulation. As such, phytocapping should be considered not as a general-purpose substitute for engineered covers, but as a climate-responsive nature-based solution that can complement urban waste servicing infrastructure, ecological restoration and adaptive governance of landfills when properly designed, monitored and regulated. Full article

Heavy metal (HM) contamination in urban soils is a pressing global issue, particularly in rapidly industrializing regions like Kazakhstan, where anthropogenic activities such as transportation, energy production, and manufacturing exacerbate accumulation in ecosystems. In Almaty, the largest city in Kazakhstan, urban expansion and legacy pollution pose risks to soil functions, biodiversity, and public health through bioaccumulation and migration pathways. This study evaluates the spatial distribution and ecological impacts of total heavy metal concentrations (HMs) (Pb, Cd, As, Zn, Cu, Ni, Co, Mo, Mn) in Almaty’s soils to inform remediation strategies. Soil samples (n = 73) were collected using a systematic grid sampling method across urban, industrial, and peri-urban zones in Almaty. HM concentrations were determined via X-ray fluorescence spectrometry (XRF) following GOST 33850-2016 standards. Pollution indices (contamination factor K_c and integrated pollution index Z_c) were calculated relative to Kazakhstani permissible limits (PDK RK) and Russian approximate permissible concentrations (ODK RF). Statistical analyses included Spearman’s correlation, boxplots, and coefficient of variation. Morphological, physicochemical (pH, humus content), and biological assessments evaluated degradation. Spatial interpolation via GIS mapped the hotspots. HM distributions showed significant variability, with As, Zn, and Ni exceeding norms in >90% of samples (median K_c ≈ 5 for As). Z_c classified >70% of sites as hazardous or extremely hazardous (Z_c > 32), with hotspots in central-eastern districts (Z_c 90–145). Strong correlations (ρ ≥ 0.6) identified a technogenic group (Pb–Zn–Cu–Ni) from traffic and industry, contrasting predominantly geogenic elements with possible anthropogenic contribution (As–Co–Mo–Mn). Pollution induced soil compaction, reduced humus/pH, and disrupting biogeochemical cycles. Local exceedances were noted near TECs, factories, and transport hubs. Almaty’s soils exhibit pervasive technogenic HM pollution, driven by urban sources, leading to ecosystem degradation and health risks. Future research should incorporate vertical profiling and isotopic sourcing for refined risk models. Prioritized monitoring and phytoremediation in hotspots are recommended to enhance resilience, aligning with UN SDGs for sustainable cities and ecosystems. Future research should incorporate vertical profiling and isotopic sourcing for refined risk models. Full article

Microplastic contamination in soils is an emerging environmental challenge requiring effective and scalable remediation strategies. This review synthesizes advances in physical, chemical, biological, and hybrid approaches, focusing on mechanisms, performance, and practical applicability. Physical methods, particularly adsorption using biochar, achieve removal efficiencies exceeding 86% for 1 μm polystyrene microplastics and maintain > 85% efficiency after multiple reuse cycles, demonstrating strong durability. Filtration and aggregation systems, such as permeable reactive barriers, reach up to 81.55% removal but are less effective in co-contaminated conditions. Chemical strategies exhibit the highest efficiencies. Dielectric barrier discharge plasma achieves 96.5–98.7% degradation within 30–60 min, while electrochemical coagulation reaches ~98% removal via flocculation. Thermal treatments, including pyrolysis, enable near-complete microplastic removal (~100%) at ≥400 °C, although high energy demands limit in situ application. Chemical amendments also improve soil quality, increasing organic matter by ~7.35% and enhancing nutrient availability. Biological approaches offer sustainable but slower remediation. Microbial degradation achieves up to ~60% breakdown within 21 days, while enzyme–microbe systems reach ~21.4% over 60 days. Earthworm activity enhances fragmentation and nutrient cycling (up to 36.1%), whereas phytoremediation alone shows minimal direct degradation (<1% over 12 months). Hybrid strategies, particularly biochar-based systems, provide the most practical solutions by combining adsorption, microbial stimulation, and soil restoration, but their effectiveness in degrading microplastics needs further verification. These systems enhance microbial biomass (up to 57.67%), nutrient availability (up to 66.02%), and crop yield (up to 81.41%). Overall, physicochemical methods ensure rapid removal (>90%), biological approaches support long-term degradation, and hybrid systems offer scalable, sustainable remediation for field applications. Full article

Cadmium (Cd) and lead (Pb) co-contamination in construction and demolition waste landfill soils presents a significant challenge to ecosystem health, necessitating effective remediation strategies. This study investigated a synergistic approach combining a composite amendment (compost, superphosphate, desulfurized gypsum) with seven plant species to elucidate the interactions driving metal immobilization and phytoextraction. The amendment significantly altered soil properties: it reduced total Cd while increasing its bioavailability, and enhanced soil fertility (e.g., elevated organic matter and total nitrogen). Plant responses varied: Solanum americanum Mill. and Tagetes patula L. exhibited high Cd phytoextraction capacity, whereas Lolium perenne L. sequestered Cd/Pb primarily in roots. The bacterial community shifted from an oligotrophic, stress-tolerant state (e.g., Sphingomonas-dominated) in contaminated soil to a copiotrophic, functionally active state (e.g., Streptomyces-enriched) in amended soil. Community structure was strongly correlated with available Cd, pH, and nutrient levels. Key microbial biomarkers were specifically enriched in different plant rhizospheres. In contrast, the fungal community exhibited minimal responsiveness. These findings demonstrate that remediation efficiency is governed by an integrated “amendment–plant–microbe” framework: amendments regulate metal bioavailability, plants execute extraction or stabilization, and the restructured microbiome supports nutrient cycling and plant health. This integrated remediation strategy directly supports the Sustainable Development Goals of the 2030 Agenda, especially on environmentally sound management of chemicals and wastes and land degradation neutrality. This mechanistic understanding underscores the necessity of combined biological and chemical strategies for sustainable remediation of co-contaminated soils, ultimately enabling ecological reclamation and safe recycling of such urban marginal lands into productive uses. Full article

Magnetic nanocomposite sorbents are increasingly explored for the remediation of metal-contaminated waters; however, high abiotic removal efficiency may not always translate into biological safety. The present study evaluated the single and combined effects of dissolved cobalt (II) ions and magnetite–chitosan nanocomposites (MCN) in zebrafish (Danio rerio) embryos and larvae. MCN (30 wt.% Fe₃O₄) were synthesized via co-precipitation and crosslinking and physiochemically characterized. Adsorption experiments conducted in fish incubation medium demonstrated the efficacy of divalent Co removal and were well described by the Langmuir isotherm model, with a maximum experimental capacity of 20.08 mg g⁻¹. The biological endpoints encompassed survival, hatching, heart rate, locomotor behavior, and oxidative stress biomarkers in early-stage zebrafish. The presence of cobalt (II) was found to result in a reduced hatching success rate, the induction of persistent bradycardia, and the occurrence of oxidative stress, as evidenced by a decline in SOD activity and an increase in H₂O₂ and MDA levels. The study found that MCN alone did not lead to mortality or increase peroxide levels or lipid peroxidation, although a modest decrease in SOD activity was observed. In contrast, combined exposure to cobalt and MCN resulted in significant delayed mortality (>85% at 96 h) and early neuromotor impairment. These findings indicate that high abiotic sorption efficiency alone does not guarantee reduced biological toxicity when nanomaterial–metal interactions occur. Consequently, safety assessments of remediation nanomaterials should explicitly consider nanomaterial–metal interactions and developmental stage-specific biological responses. Full article

Chromium (Cr) is a common heavy-metal pollutant that poses a significant threat to both the environment and human health. Herein, a novel strain Lysinibacillus capsici FPHNCRA4-48, with a high Cr tolerance and removal performance, was isolated from Cr-contaminated plant water in Changde, Hunan Province. Structural characterization and proteomic analyses were performed to investigate the Cr removal performance and molecular mechanism of L. capsici FPHNCRA4-48. FPHNCRA4-48 can effectively remove more than 99% of the Cr(VI) at an initial concentration of 1000 μmol/L. The FTIR, 3D-EEM, and XPS results revealed that -OH, -NH₂, and -CO-NH₂ derived from extracellular polymeric substances (EPSs) were mainly involved in Cr(VI) removal. Interestingly, the protein content in the EPS increased significantly (1.32-fold) after exposure to Cr(VI). Moreover, proteomic analysis revealed that genes (rpmA, rpmI, rpmC, rplI, rpmD, deoB, deoC) related to translation and carbohydrate metabolism, and genes (pyk, icd, rpiB, eno) related to amino acid biosynthesis were all significantly up-regulated, suggesting that these pathways related to protein synthesis in L. capsici FPHNCRA4-48 were activated under Cr(VI) stress. Finally, KEGG ribosome pathway enrichment occurred. These data highlight the importance of microbial EPSs in bioremediation in Cr-polluted environments. This study identified highly efficient Cr(VI)-removing bacterial strains and conducted an in-depth analysis of the removal mechanism of their extracellular polymeric substances (EPSs), thereby providing theoretical foundations and technical support for the biological remediation of Cr(VI)-contaminated water bodies. Full article

Soil contamination by per- and polyfluoroalkyl substances (PFAS) represents a pressing environmental and public health concern due to the exceptional persistence of carbon–fluorine bonds, which prevent natural attenuation and limit the effectiveness of conventional remediation. Agricultural and industrial soils serve as long-term sinks for PFAS, continuously releasing these pollutants into groundwater and facilitating their transfer through the food chain. Conventional chemical and physical remediation methods are often costly, energy-intensive, and yield incomplete removal, underscoring the need for sustainable and biologically driven alternatives. Microbial consortia have emerged as a promising solution due to their metabolic complementarities, cross-feeding interactions, and ecological resilience, which together enable PFAS transformation and partial defluorination under complex soil and subsurface conditions. Key enzymes such as oxygenases, reductive dehalogenases, and hydrolases are often operating within co-metabolic networks, which play central roles in these processes. Advances in metagenomics, CRISPR-based functional screening, and metabolic modelling are rapidly uncovering novel PFAS-degrading microbes and pathways. Integration of machine learning with multi-omics and environmental datasets further enables the prediction of degradation mechanisms, identification of keystone degraders, and rational design of synthetic consortia. Emerging sustainable strategies, including biochar- and nutrient-amended soil microcosms, plant–microbe partnerships for coupled soil–groundwater phytoremediation, and bioelectrochemical systems that offer new avenues for enhancing PFAS biodegradation in situ. This review synthesises recent research progress and provides critical perspectives on the mechanistic, ecological, and engineering dimensions of PFAS bioremediation, proposing an integrated conceptual framework linking microbial consortia dynamics, enzymatic pathways, and environmental engineering interventions to guide scalable field applications and sustainable management of PFAS-contaminated soil–groundwater ecosystems. Full article

Cadmium (Cd) contamination in agricultural soils severely impairs plant growth, disrupts microbial communities, and threatens food safety due to its high toxicity and mobility. Conventional remediation methods are often expensive and environmentally unsustainable. In contrast, plant–microbiome interactions offer an eco-friendly solution to reduce Cd accumulation and improve plant growth. Arbuscular mycorrhizal fungi (AMF) and mycorrhiza helper bacteria (MHB) are known to improve plant growth and resilience in Cd-contaminated soils. However, the mechanisms by which AMF and MHB co-inoculation could reduce soil Cd contamination by altering the rhizosphere fungal community remain unclear. This study aimed to evaluate how co-inoculation with AMF (Funneliformis mosseae) and MHB (Alcaligenes faecalis) affects plant Cd uptake and soil Cd content, and how it reshapes the cucumber rhizosphere fungal community. A greenhouse experiment was conducted with four treatments: CK (no inoculation), Fm (AMF inoculation), Af (MHB inoculation), and FA (AMF + MHB co-inoculation). Co-inoculation with AMF and MHB (FA) significantly reduced Cd concentrations in both plant tissues and soil. Fungal communities were profiled using Illumina MiSeq sequencing of the ITS region, and diversity metrics and structural changes were assessed through PCoA and DESeq2. Co-inoculation (FA) significantly reshaped the fungal community, increasing the relative abundances of beneficial phyla such as Mortierellomycota, Basidiomycota and Glomeromycota, while decreasing the abundance of potentially pathogenic Ascomycota. Double inoculation with AMF and MHB also enhanced fungal diversity, as measured by the Simpson index, and enriched specific OTUs. This study uncovers the mechanisms through which AMF–MHB co-inoculation reduces Cd concentrations in both plants and soil by altering the cucumber rhizosphere fungal community composition. These findings demonstrate that AMF–MHB co-inoculation is an effective, biologically driven strategy for remediating Cd-contaminated soils by restructuring cucumber rhizosphere fungal communities. Full article

Earthworms are widely used as biological indicators of soil contamination and are often referred to as the ‘intestine of the soil’; however, their effectiveness can vary across regions and environmental conditions. The performance of earthworms as indicators of soil pollution may vary among regions, and there is a need to assess their reliability under specific environmental conditions. So, in this study, soil and earthworm samples were collected from 19 locations across Punjab, Pakistan, to assess heavy metal pollution and bioaccumulation using geoaccumulation indices (Igeo) and bioaccumulation factors (BAF). Soil and earthworm tissues were digested and analyzed for heavy metals such as Sr, Zn, Ca, Cu, Fe, Mn, Co, Cr, Pb, Cd and Ni using ICP-MS. According to Igeo, cadmium frequently classified soils as strongly to extremely polluted, with values up to 4.5 in Bahawalnagar, whereas most other metals fell within the unpolluted to moderately polluted classes. Earthworms showed clear bioaccumulation (BAF > 1) for several essential or poorly regulated elements, particularly Ca, Mn, Cu and Sr; the maximum BAF for Ca reached 8.18 in Faisalabad. In contrast, group-1 carcinogenic metals (Pb, Cd and Cr) generally did not exhibit strong bioaccumulation. Relationships between BAF and soil metal concentrations or abiotic properties (moisture, pH, electrical conductivity, total dissolved and suspended solids) were generally weak (R² typically ≤ 0.32), indicating that these factors explain only a modest fraction of the variation in metal uptake. Overall, the results highlight cadmium as the primary soil contamination risk in the surveyed areas. Because bioaccumulation showed weak relationships with soil metal concentrations and physicochemical parameters, earthworms in this study demonstrated limited effectiveness as bioindicators of toxic heavy metal accumulation. The limited internal accumulation of highly toxic metals suggests possible physiological regulation or tolerance, although the long-term ecological implications require further investigation. Further controlled studies are necessary to better evaluate their ecological role and potential applications in soil remediation, waste management, and vermicompost production. Full article

Cement production exerts a significant negative impact on the environment through the emission of greenhouse gases, particulate matter (PM), heavy metals, and other toxic substances into the atmosphere, soil, and bodies of water, degrading the environment and affecting the population’s health. This study reviews different solutions to reduce pollution and mitigate its effects. Particular attention is given to Carbon Capture, Utilization, and Storage (CCUS) technologies and their ability to significantly reduce CO₂. Biomass and waste-derived fuels were identified as viable substitutes for fossil fuels, although challenges related to supply chain reliability and secondary environmental impacts remain. The study further examined mitigation strategies for non-gaseous pollutants, including noise pollution control measures such as sound barriers and vibration isolation systems, soil remediation techniques such as phytoremediation and the recycling of cement kiln dust (CKD), and water pollution control technologies, including filtration, chemical precipitation, biological treatment, and Zero Liquid Discharge (ZLD) systems. Key research gaps were identified, particularly concerning the long-term durability, scalability, and cost-effectiveness of these mitigation approaches. Overall, the review emphasizes the need for integrated pollution control strategies to support the transition toward a more sustainable cement industry and recommends future research focused on developing mitigation technologies that are efficient, economically viable, and adaptable to large-scale industrial applications. Full article

In the last 32 years (1993–2024), the application of electric fields in soil management (soil electrokinetic, SEK) has undergone several stages of optimization and intensification. SEK has used both alternating current (AC) and direct current (DC). Numerous fields, including agriculture, sedimentation, phosphorus management in soil and sludge, fertilizer production, consolidation, reclaiming salt-affected soils, metal extraction, dewatering, remediation of contaminated soil (both organic, such as PFAS, and inorganic, such as heavy metals), and soil nutrient availability, have utilized the SEK concept. Numerous innovations were included in the SEK equipment’s design or combined with other biological, chemical, and physical processes. While we recently published a review article on soil electrokinetic/electroosmosis–vacuum systems for sustainable soil improvement and contaminant separation, the current study illustrates the role of applying the pressure-assisted soil electrokinetics technique and shows the effect of the opposite technique. Four points were used to show the function of pressure-assisted soil electrokinetics based on our analysis of six search engines from 1993 to 2024 (the previous 32 years), including (1) polluted soil remediation, (2) dewatering, (3) soil improvement, and (4) making soil ready for electrokinetic action by applying pressure. In contrast to other intensification methods (such as reverse polarity, pulsed electric field, and design change), we found very few publications addressing pressure-assisted soil electrokinetics throughout the literature search. Most investigations focused on the dewatering mechanism, despite the paucity of relevant papers. In contrast to conventional electrokinetic remediation, pump-assisted electrokinetic-flushing remediation increased the removal efficiencies of Cs⁺ and Co²⁺ from contaminated soil by 2% and 6%, respectively. Additionally, the results demonstrated that the pressured electro-osmotic dewatering approach outperformed the conventional electrokinetic techniques. At 40 kPa, hydraulic conductivity was reduced four-fold by electro-rehabilitation for alternative fuels, while at 100 kPa, it was reduced three-fold. It was also observed that pressure may be used to achieve the soil ready for electrokinetic action in order to guarantee proper operation. Since there are not many articles on the subject, future research may examine how pressure-assisted soil electrokinetics can be integrated with vacuum systems, reverse polarity mode, pulsed electric field mode, modifying the SEK design, overcoming the formation of cracks, etc. Full article

β-blockers are among the most widely prescribed cardiovascular drugs and are increasingly recognised as emerging pollutants due to their persistence, continuous release into aquatic environments, and potential toxicological effects on aquatic organisms. Their removal in conventional wastewater treatment plants is often inefficient, highlighting the need for biological remediation strategies. This study aimed to identify bacterial strains with the highest potential for the biotransformation of β-blockers. Therefore, we isolated and characterised bacterial strains capable of transforming two commonly used β-blockers—propranolol and metoprolol. The strains BB2 and BB3, which were able to transform propranolol and metoprolol, respectively, were identified as Raoultella terrigena and Stenotrophomonas terrae, respectively. BB2 showed broad metabolic versatility, utilising a wide range of carbon sources, whereas BB3 exhibited limited substrate utilisation. Antibiotic resistance profiling further distinguished the strains, with BB2 resistant across multiple antibiotic classes and BB3 largely sensitive. Co-metabolic assays demonstrated that supplementation with specific carbon and nitrogen sources markedly enhanced β-blocker removal, increasing propranolol biotransformation from 5% to 50% and metoprolol from 4% to 36%. These findings demonstrate the bioremediation potential of newly isolated strains and emphasise the importance of aligning microbial metabolic traits with nutrient conditions to improve pharmaceutical removal in wastewater treatment systems. Full article

The rapid growth of the human population and industrialization has intensified anthropogenic activities, leading to the release of various toxic chemicals into the environment, triggering significant risks to human health and ecosystem stability. One sustainable solution to remove toxic chemicals from various environmental matrices, such as water, air, and soil, is bioremediation, an approach utilizing biological agents. Microalgae, as the primary producers of the aquatic environment, offer a versatile bioremediation platform, where their metabolic processes break down and convert pollutants into less harmful substances, thereby mitigating the negative ecological impact. Besides the CO₂ sequestration potential, microalgae are a source of renewable energy and numerous high-value biomolecules. Additionally, microalgae can mitigate various toxic chemicals through biosorption, bioaccumulation, and biodegradation. These remediation strategies propose a sustainable and eco-friendly approach to address environmental pollution. This review evaluates the microalgal mitigation of major environmental contaminants—heavy metals, pharmaceuticals and personal care products (PPCPs), persistent organic pollutants (POPs), flue gases, microplastics, and nanoplastics—linking specific microalgae removal mechanisms to pollutant-induced cellular responses. Each section explicitly addresses the effects of these pollutants on microalgae, microalgal bioremediation potential, bioaccumulation process, the risks of trophic transfer, and biomagnification in the food web. Herein, we highlight the current status of the microalgae-based bioremediation prospects, pollutant-induced microalgal toxicity, bioaccumulation, and consequential biomagnification. The novelty of this review lies in integrating biomagnification risks with the bioremediation potential of microalgae, providing a comprehensive perspective not yet addressed in the existing literature. Finally, we identify major research gaps and outline prospective strategies to optimize microalgal bioremediation while minimizing the unintended trophic transfer risks. Full article