Portland cement production is a major contributor to global CO2 emissions, while large volumes of mine tailings remain stockpiled as long-term environmental liabilities. This study investigates valorisation of copper mine tailings (CMT) as a supplementary cementitious material within a resource recovery framework. Intrinsic reactivity was quantified using the R[3] test and linked to hydration behaviour through isothermal calorimetry, X-ray diffraction, FTIR and scanning electron microscopy, alongside compressive strength evaluation. The CMT exhibited an R[3] heat release of 156 J/g, confirming its intrinsic pozzolanic reactivity. Isothermal calorimetry showed that a 10% clinker replacement reduced cumulative heat release by only 2.67%, indicating partial compensation of clinker dilution through filler and pozzolanic effects. A cradle-to-gate life cycle assessment employing system expansion quantified environmental benefits from clinker displacement and avoided tailings storage burdens. Climate change impacts decreased from 0.935 to 0.583 kg CO2-eq with increasing CMT replacement, despite an 1800 km transport distance. Impact reductions were predominantly driven by clinker substitution, with additional gains from mitigating waste accumulation. These findings demonstrate a technically viable pathway for integrating CMT into lower-carbon blended cement.

Per- and poly-fluoroalkyl substances (PFAS) present a significant challenge for human, wildlife, and environmental health due to their persistence and bioaccumulative tendencies. Despite growing public concern, information on PFAS in many plants and animals is relatively limited. This information gap includes species harvested for human consumption and traditional Indigenous foods. As PFAS contamination may pose disproportionate risks to Indigenous food sovereignty and lifeways, understanding the potential presence of these contaminants in traditional foods is crucially important. Seeking to address the information gap, this Tribally driven study analyzed PFAS in two species of aquatic plants: Manoomin (Zizania palustris) and Psiŋčiŋča (Sagittaria latifolia). Found across the Great Lakes region, these plants have both ecological importance and cultural significance for Indigenous peoples. In Psiŋčiŋča, no PFAS were detected above the minimum level of detection (LOD). In Manoomin, four PFAS (perfluoro(2-ethoxyethane) sulfonic acid (PFEESA), perfluorohexane sulfonic acid (PFHxS), perfluorooctane sulfonic acid (PFOS), perfluoro-n-pentanoic acid (PFPeA) were detected in varied plant tissues (roots, stalks, and seeds). All PFAS were detected at levels below 2 ng/g that are unlikely to pose a risk for human consumption at this time. This study is the first to investigate PFAS bioaccumulation in Manoomin or Psiŋčiŋča and quantifies PFAS in surrounding environmental matrices (sediment and surface water). These findings highlight potential exposure pathways for harvesters and can help to inform Tribal food sovereignty initiatives. This study establishes a foundation for future research exploring the impacts of PFAS on the health of Manoomin, Psiŋčiŋča, and the overall condition of aquatic ecosystems.

Per- and polyfluoroalkyl substances (PFAS) are emerging contaminants known for their persistence and potential health risks. Stormwater runoff serves as a major pathway for contaminant transport into aquatic ecosystems, yet data on the occurrence, distribution, and transport of PFAS via stormwater runoff remain limited. This study revealed PFAS in stormwater runoff from high- and low-traffic areas in Trenton and Glassboro, NJ, during precipitation events from February to August 2024, and explored the removal of PFAS by drinking water treatment residuals (WTRs). Results showed that perfluorooctanesulfonic acid (PFOS), perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), and perfluoropentanoic acid (PFPeA) were the most prevalent PFAS compounds in the stormwater runoff in both locations. PFAS concentrations were significantly higher in high-traffic than low-traffic areas in both cities, with Trenton showing higher levels than Glassboro, reaching 444 ng/L and 233 ng/L, respectively. PFAS levels were highest at rainfall onset and gradually declined as precipitation continued. Adsorption studies using Al-WTR for representative legacy and emerging PFAS showed a maximum adsorption capacity of 121 μg/g for PFOS, followed by PFNA (101.5 μg/g), PFOA (96.3 μg/g), HFPO-DA (76 μg/g), PFBS (67 μg/g), and PFHxS (66.7 μg/g). These findings provide critical insights into PFAS distribution, transport, and removal in urban stormwater runoff, emphasizing the roles of traffic and stormwater dynamics in PFAS dispersal.

Airborne microplastics (MPs) have emerged as environmental pollutants that can co-occur with hazardous contaminants; however, evidence of heavy-metal associations with atmospheric MPs remains limited. This study investigated the abundance, characteristics, metal loadings, and health risks of airborne MPs in Metro Manila, Philippines. Air samples were collected from classroom, laboratory, dining room, office, living room, and store environments, followed by polymer identification via μFTIR and metal quantification using ICP-MS. MP concentrations ranged from 0.074 to 0.595 MP/m[3] indoors (mean: 0.297 ± 0.20 MP/m[3]) and from 0.057 to 0.262 MP/m[3] outdoors (mean: 0.173 ± 0.07 MP/m[3]), with no statistically significant difference. Fibers dominated the MP assemblage (52.38%), followed by fragments and films. PP, PET, and PE were the most prevalent polymers. Heavy metal concentrations ranged from 0.35 to 27521.66 mg/kg indoors and from 0.11 to 30556 mg/kg outdoors, with notable contributions from Zn, Cu, Ba, Pb, and Ag. These showed site-specific variations associated with room function and anthropogenic activity, with elevated Cu and Zn in high-activity indoor spaces. Pollution indices (PLI, MPI) indicated moderate pollution levels, while the ecological risk index indicated moderate ecological risk. Spearman analysis showed strong positive correlations between MPI-HM and As, Fe, and Zn (r = 0.70, p < 0.05), while PCA and HCA differentiated sampling sites by metal- and MP-related profiles. Inhalation risk assessment indicated low-to-moderate non-carcinogenic risk; however, the co-occurrence of toxic metals with respirable MPs highlights the occurrence of hazardous substances within the recovered airborne MP fraction. This study provides one of the first assessments of heavy metals associated with airborne MPs in indoor-outdoor urban environments.

Antibiotic pollution in water systems is a critical global challenge that worsens the global water scarcity crisis by contaminating vital freshwater reserves and creating dangerous antimicrobial resistance. Photocatalysis uses solar energy to power green catalytic treatments that clean antibiotic-contaminated water by breaking down persistent pharmaceuticals without using any harsh chemicals. Bismuth-based heterojunction photocatalysts leverage heterojunction engineering that drastically improves charge carrier separation and minimizes electron-hole recombination while enhancing redox potential for the destruction of environmental pollutants. In this article, we reviewed the removal of levofloxacin (LEV) and ciprofloxacin (CIP), the two most detected antibiotics in wastewater and aquatic environments globally, by various bismuth-based heterojunctions. Their photodegradation performance has been compiled and compared, and possible degradation routes, photodegradation mechanisms, and ecotoxicity of the degraded products are discussed. A true comparison of the degradation performance of CIP and LEV by various heterojunctions is difficult because various light sources, radiation intensity, pollutant concentration, and catalyst dose were used in various published studies. Of the heterojunctions so far developed, Fe3O4/Bi2WO6 and Bi2O3/(BiO)2CO3 showed excellent CIP removal, and their photodegradation rate constants were 0.5571 and 0.476 min[-1], respectively. Conversely, for the removal of LEV, Bi2WO6/CuS and BiOCl/Bi2Fe4O9 provided excellent photodegradation, and the rate constants were 0.2639 and 0.0934 min[-1], respectively. Toxicity analyses show that many degradation intermediates of CIP and LEV are toxic and mutagenic if the photodegradation is incomplete. The development of low-cost photocatalytic drug removal technology based on bismuth-based heterojunctions holds significant potential to make drinking water safer for human and animal consumption.

Crude oil spills remain a persistent global environmental challenge, while polyethylene (PE) waste continues to accumulate, particularly in low-resource settings. This study develops a circular-economy approach that directly addresses both issues through the valorisation of post-consumer PE water sachets into effective, low-cost sorbents for oil spill remediation. Waste PE was mechanically processed and modified via NaCl-assisted abrasion to produce shredded polyethylene (S-PE) and surface-roughened polyethylene (SR-PE). Characterisation by scanning electron microscopy (SEM) confirmed increased surface roughness and microcavity formation, while Fourier-transform infrared spectroscopy (FTIR) indicated minor surface oxidation following abrasion. Response surface methodology and I-optimal design were used to evaluate the effects of sorbent type, particle size, sorbent dose, and oil loading. Sorbent morphology was the dominant performance factor, with SR-PE achieving oil uptake capacities of approximately 8 g/g for synthetic crude oil and 5.9 g/g for natural crude oil under optimised conditions using a 5 min operational contact time. Natural crude oil adsorption showed reduced sensitivity to operating conditions, indicating robust performance across the investigated conditions. Regeneration studies showed an initial decline followed by stabilisation of adsorption capacity, demonstrating sustained multi-cycle performance. A techno-economic assessment based on stabilised reuse performance estimated lifecycle oil-removal costs of 0.042-0.130 USD/kg oil, lower than representative literature-based estimates for commercial polypropylene sorbents. Overall, the integration of simple material modification, statistical optimisation, regeneration, and economic assessment demonstrates the potential of recycled PE as a reusable, low-cost sorbent for oil spill remediation.

Plastic fragmentation represents a risk for ecosystems. Hummingbirds (Trochilidae) are nectarivorous birds restricted to the Americas, where they fulfill critical ecosystem roles as pollinators. The aim of this study was to assess the occurrence of meso- and microplastics (MMPs) in the gastrointestinal tract (GIT) of three hummingbird species from the floodplain of the Middle Paraná River (Argentina). Necropsies were conducted to extract the stomach and intestine, which were chemically digested. All particles were counted and classified by morphology, size and color, while a representative sub-sample of fibers (n = 32) and all fragments and films were selected for FTIR characterization. A total of 237 particles were visually identified and grouped by morphology into 228 microfibers, 5 mesofibers, 3 fragments and 1 film. Size fractions between 0.063 and 2 mm accounted for 82.28% of the total of particles. Of the 36 particles chemically characterized by FTIR, 14 were confirmed as synthetic plastic polymers. Two fragments were identified as polyurethane, one as polyamide, and the only film as polyamide, while polyester (n = 6, 19%) and polypropylene (n = 4, 12%) were identified in fibers. The remaining 22 particles, all fibers, were identified as cellulose of uncertain origin (69% of the analyzed fibers). Abundance ranged from 8 to 36 particles/bird. No statistically significant differences were detected among the three species (nCl = 5, nHf = 2, nHc = 4). Multiple potential ingestion routes for MMPs in nectarivorous birds were proposed, including potentially contaminated nectar, pollen, water, and insect prey. These findings highlight a potential exposure concern for hummingbirds that requires further investigation.

Wastewater and biosolids are important pathways of chemicals to the environment and thus are often included in monitoring programs. Wastewater samples are often stored frozen when insufficient resources prevent immediate analysis or when samples are included as part of environmental specimen banks. However, the stability of chemical substances in frozen samples is not well known. The objective of this study was to evaluate the stability over a one-year period of three substance groups: bisphenols, halogenated flame retardants (HFRs), and pesticides in frozen (-20 °C) wastewater media. Influent, effluent, and biosolids samples were collected from two wastewater treatment plants (WWTPs) and target analytes were spiked into each sample. Three influent, effluent, and biosolids samples from both WWTPs were immediately chemically analyzed and triplicate influent, effluent, and biosolids samples from both WWTPs were analyzed after approximately 30-70, 180, and 365 days of frozen storage. The bisphenols (except bisphenol E), all but one HFR (pentabromobenzyl bromide), and pesticides in the organochlorine, organonitrogen, and pyrethroid groups were highly or moderately stable during frozen storage. Although most organophosphates and triazines were also highly or moderately stable, there were seven analytes in these pesticide groups, namely chlorpyriphos-oxon, diazinon-oxon, disulfoton sulfone, malathion, phosmet, ametryn, and metribuzin that were not stable. Consistent differences in chemical stability were not observed between the different wastewater matrices or time frozen. This study indicates that wastewater and biosolids samples can be stored frozen with confidence that concentrations of bisphenols, HFRs, and pesticides are not affected by chemical transformation, with a few exceptions.

Hexavalent chromium, Cr(VI), is a highly toxic and mobile water pollutant whose removal is critical for environmental and human health. In this study, a rice-husk-derived biochar-supported cobalt-doped molybdenum disulfide composite (BC@Co-MoS2) was developed for Cr(VI) removal, with emphasis on its interfacial structure, storage-induced evolution, and removal mechanism. The biochar support improved Co-MoS2 dispersion and suppressed severe restacking, providing a heterogeneous reactive interface. One month of natural aging increased the 15-min Cr(VI) removal efficiency from approximately 31.9% to 93.8%. Controlled storage experiments showed that this performance change was associated with oxidative exposure rather than storage time alone. Naturally aged BC@Co-MoS2 produced 240 mg L[-1] sulfate after 120 min, 4.8 times that of the inert-stored material, accompanied by proton-releasing behavior and oxidation-related evolution of the Mo-S domains. When self-acidification was suppressed by maintaining the solution at pH 6.0, the difference in Cr(VI) removal between fresh and aged materials decreased to approximately 2 percentage points, indicating that the apparent enhancement was governed predominantly by a pH-mediated effect rather than increased intrinsic removal capacity. Time-dependent chromium speciation revealed the transient formation of dissolved Cr(III), while Cr 2p XPS confirmed Cr(III) on the spent composite, supporting a coupled Cr(VI) reduction-retention pathway. These findings demonstrate that storage-induced interfacial evolution can substantially alter the apparent reactivity of MoS2-based composites and should be considered when evaluating their performance and stability.

Long-range transport of mercury (Hg) pollution and bioaccumulating microplastics (MPs) is a severe issue, and polar environments are continuously changing. To critically discuss the hypothesis of the "Trojan-Horse," in which MPs might be carriers of increased Hg bioavailability and/or biomagnification in the polar bird food web. It integrates information on MP contamination in Arctic and Antarctic environments, the transport of Hg via Arctic and Antarctic food chains, and the interactions between MP and Hg toxicity. Laboratory studies have shown that UV-aged MPs can significantly increase Hg bioaccumulation (up to 1.61-fold), oxidative stress, neurotoxicity, and multigenerational reproductive toxicity. Polar seabirds have also been reported to have a high MPs ingestion frequency (FO: 15-93%) and biomagnification of Hg (2.3-8.6). Field studies have provided evidence of a link between MP ingestion and an increase in the Hg burden, which is somewhat contradictory to laboratory studies. Nanoplastics (NPs) may be an underestimated vector because of their high surface area-to-volume ratio and membrane-penetrating ability. Foraging/hunting ecology, foraging level, and migration result in varying vulnerabilities among albatrosses, petrels, fulmars, skua, and penguins. Some of the key gaps are limited in-field validation, seasonal plastic and Hg transfer processes, variable co-contaminant monitoring, and a lack of predictive models of plastic-Hg trophic interactions.

The persistence of microplastics (MPs) in aquatic environments challenges conventional water treatment systems, increasing demand for sustainable removal materials. This study investigated the influence of KOH activation on the structural properties of durian peel biochar and its performance for polyethylene terephthalate (PET) microplastic removal from aqueous systems. Batch experiments evaluated biochar modification, contact time, and solution pH. Physicochemical characterization revealed that KOH activation substantially enhanced surface area, pore development, and surface structural complexity. Post-adsorption FE-SEM showed PET retention on rough surfaces, cracks, and structural cavities, while XPS revealed an increase in the O/C atomic ratio from 0.13 to 0.21 and the appearance of an ester-related O-CO component, supporting PET retention on the biochar surface. Under optimum conditions (4 g L[-1], pH 5, 180 min), KOH-activated biochars achieved PET removal efficiencies of 86.83-90.50%, substantially higher than unactivated biochars (51.00-51.17%) and comparable to commercial activated carbon (88.50%). PET removal decreased with increasing pH, indicating that solution chemistry influenced PET-biochar interactions. The pseudo-first-order model provided the best empirical description of the time-dependent PET retention behavior under the investigated conditions. Considering the large PET particle size (20-53 μm) relative to the predominantly microporous structure, enhanced removal was attributed primarily to accessible external-surface retention and physicochemical interactions rather than direct micropore filling. These findings demonstrate that KOH activation effectively improves the structural properties and PET retention performance of durian peel biochar, highlighting its potential as a bio-based material for microplastic mitigation.

This study presents a comprehensive seasonal assessment of groundwater hydrogeochemistry and quality in Ashti tahsil, a predominantly agricultural region overlying Deccan basalt aquifers in central India. Physicochemical parameters, major ion chemistry, mineral saturation indices, and multi-parameter water quality indices were evaluated for pre-monsoon and post-monsoon periods across forty wells. Groundwater exhibited a neutral to slightly alkaline pH (7.1-8.0), controlled by carbonate buffering through the dissolution of calcite and dolomite. The dominant hydrochemical facies was Ca-Mg-HCO3, reflecting carbonate dissolution and water-rock interaction with subordinate agricultural inputs. Total dissolved solids exceeded the Bureau of Indian Standards (BIS) acceptable limit of 500 mg/L in 55% and 45% of pre- and post-monsoon samples, respectively, indicating moderate anthropogenic influence, mainly from agricultural return flow and the leaching of fertiliser-derived soluble salts (nitrate, chloride and sulphate), which enhance dissolved ion loads in the shallow aquifer. Nitrate contamination emerged as the primary public health concern, with 40-45% of wells exceeding the 45 mg/L BIS threshold (maximum: 176 mg/L), primarily due to excessive agrochemical application. PHREEQC thermodynamic modelling confirmed near-equilibrium carbonate mineral controls, while consistently undersaturated evaporite phases (halite SI: -8.24 to -5.89; gypsum SI: -4.02 to -1.42) confirmed freshwater character. The entropy-weighted water quality index (EWQI) classified 40.0% and 42.5% of samples as excellent during the pre- and post-monsoon seasons, respectively, with post-monsoon dilution improving the proportion of high-quality samples. Principal component analysis (PCA) resolved three components explaining 85.2% of total variance, identifying mineralisation, carbonate buffering, and agricultural contamination as the principal hydrogeochemical controls, while hierarchical cluster analysis resolved three hydrochemically distinct groups that remained stable across seasons. Seasonal hydrogeochemical processes were structurally stable, with monsoon recharge inducing transient dilution rather than long-term chemical evolution. These findings underscore the urgent need for integrated nutrient management strategies and targeted aquifer protection measures to prevent irreversible degradation of this critical groundwater resource.

Composting of food organics and garden organics (FOGO) supports circular-economy objectives and production of recycled organic products but may facilitate per- and polyfluoroalkyl substances (PFAS) occurrence across multiple matrices within processing systems. While PFAS in finished compost have been reported, information on the system-wide distribution of PFAS, including oxidisable precursors, within full-scale composting facilities remains limited. This study aimed to investigate the occurrence, distribution, and oxidisable precursor potential of PFAS within a full-scale in-vessel FOGO composting facility in Victoria, Australia, focusing on leachate and leachate pit sediments as potential PFAS reservoirs. Targeted analysis of 33 PFAS and the total oxidisable precursor (TOP) assay were applied to feedstock, finished compost, leachate water, and leachate pit sediments. Mean Σ33 PFAS concentrations in feedstock (4.1 μg kg[-1] dw) and finished compost (4.0 μg kg[-1] dw) were comparable. However, PFAS were also detected in leachate-associated matrices with Σ33 PFAS concentrations of 2.7 μg kg[-1] dw in leachate pit sediments and 0.42 μg L[-1] in leachate, highlighting leachate pit sediments as an important PFAS-containing compartment within the leachate collection system. Summed perfluoroalkyl carboxylic acids (ΣPFCAs) increased from 1.7 to 8.0 μg kg[-1] dw in feedstock and from 3.2 to 9.3 μg kg[-1] dw in finished compost following oxidation, demonstrating the presence of oxidisable PFAS precursor potential in both matrices. Leachate pit sediments also exhibited oxidisable PFAS precursor potential. This study provides field-based evidence of PFAS occurrence and oxidisable precursor potential in leachate pit sediments within a full-scale commercial FOGO composting facility. These findings highlight the importance of considering leachate-associated residues alongside finished compost in PFAS assessment and management as regulation of recycled organics evolves.