Introduction

Wastewater purification from widely prescribed pharmaceuticals is a critical global priority. β-blockers used to treat cardiovascular diseases are frequently detected in wastewater and have been shown to exert toxic effects on various organisms. Adsorption onto green materials has emerged as an efficient, sustainable, and environmentally friendly technique for removing such contaminants from aquatic matrices.

Methods

Μicroalgae polysaccharides (MPs) have been extracted from Spirulina platensis biomass by a hot water extraction process. Sodium carboxymethyl cellulose (CMC) has been employed as a second hydrogel building block due to its mechanical robustness and its plethora of hydroxyl groups, which serve as potential crosslinking sites via esterification with citric acid. Thin MPS:CMC:CA (21:62:17 wt:wt:wt) films have been produced by water solution casting method followed by thermal curing at 80^οC and characterized by FTIR and SEM. Batch adsorption experiments towards atenolol have been conducted.

Results

The successful synthesis of the hydrogel was confirmed. The optimum pH value was found to be 9, with a removal efficiency of 82% (C_o = 50 mg/L, dose = 1 g/L, T = 30 °C). Adsorption exhibited rapid kinetics, with 69% atenolol removal within the first 15 min and an optimum time of 150 min; the pseudo-second-order model better described the process.

Conclusions

The results indicate that microalgal polysaccharide-based hydrogels, produced in accordance with Green Chemistry Principles #3, #5, #7, and #12, can efficiently and rapidly remove a model β-blocker drug from wastewater via a chemisorption-driven adsorption mechanism.

The leaves, stems, and roots of strawberries (Fragaria × ananassa Duch.) are typically discarded, together with the pomace residues generated during industrial processing. This study evaluated the distribution of phenolic compounds, flavonoids, and anthocyanins in different plant parts and pomace to assess antioxidant activity and potential circular economy applications. Fully ripe strawberry (Fragaria x ananassa Duch.) cv. ‘Malwina’ fruits were harvested in August from Joniskis region, Lithuania. Calyces were separated and juice was pressed. The remaining agronomic waste (leaves, stems, crowns, rhizomes and roots) and pomace from juice extraction were freeze dried. Total phenolic content (TPC), total flavonoid content (TFC), and total anthocyanin content (TAC) were determined using spectrophotometric methods, while antioxidant activity was assessed using DPPH· and ABTS+- assays. Statistical analyses were performed using one-way analysis of variance (ANOVA). Fisher‘s test was applied to assess significant differences (p<0.05) between the samples. The relationship between parameters was assessed by Pearson’s linear correlation test at a p < 0.05 significance level. The results revealed that the total phenolic content (TPC) was relatively high in all parts of the strawberry (Fragaria x ananassa Duch.) plant (41–51 mg GAE g-¹ D.W.), with the leaves exhibiting the highest flavonoid content (5.1–5.3 mg QE g^-1 D.W.) and the pomace showing moderate anthocyanin levels (0.32–0.36 mg Cy3G g^-1 D.W.). Strong positive correlations were notably observed between TPC and DPPH· radical scavenging activity across most plant parts, indicating that phenolic compounds largely contribute to the antioxidant potential. Although low in flavonoids and anthocyanins, roots, crowns and rhizomes still contributed to the overall phenolic content and antioxidant capacity, indicating a source of bioactive compounds. The findings indicate that strawberry by-products are rich in phenolics and antioxidants, highlighting their potential for valorization in food, nutraceutical, and cosmetic applications within a circular economy framework.

Aquaculture has proliferated globally, accompanied by the widespread use of antibiotics like sulfamethoxazole (SMX) and trimethoprim (TMP) to manage bacterial infections and improve productivity. These chemicals are often co-administered as a combination (co-trimoxazole), and their ongoing release into aquatic habitats has aroused considerable concern due to their persistence, bioaccumulation, and promotion of antimicrobial resistance. Residues may linger in sediments, affect non-target species, and pose threats to human health through food-chain transmission. Advanced Oxidative Processes (AOPs) provide a potential technique for degrading such persistent contaminants by generating highly reactive hydroxyl radicals.

This study used a UVC/H2O2 system to simultaneously remove SMX and TMP from various aquaculture influents and effluents. The influents and effluents were collected from different aquaculture facilities, spiked with environmentally relevant concentrations of both antibiotics, and treated with the UVC/H2O2 process under controlled laboratory conditions. The process efficiency was evaluated using a combination of chemical analytical techniques and toxicity assays. Preliminary results showed that the concentration of H2O2 significantly affected the process, with % removal up to about 90% for both antibiotics observed in aquaculture influents and effluents. In all cases, SMX was removed more rapidly. In conclusion, UVC/H₂O₂ process can effectively remove both antibiotics, underscoring the potential of AOPs as long-term nd efficient treatment options for reducing antibiotic contamination in aquaculture systems.

Acknowledgements: "The research project is implemented in the framework of H.F.R.I. call "3rd Call for H.F.R.I.'s Research Projects to Support Faculty Members & Researchers" (H.F.R.I. Project Number: 26141).

Quarrying drives infrastructure and economic growth but poses significant environmental challenges in urbanizing areas like Akure North, Ondo State, Nigeria. This study conducted an Environmental Impact Assessment (EIA) focusing on air quality and quarry site expansion by integrating remote sensing and GIS techniques. Multi-temporal satellite imagery (2014–2024) from Landsat 8/9 and Google Earth Pro was processed via GEE for LULC classification and change detection. Air quality data for PM2.5 and PM10 (2021–2024) was obtained from the OpenWeatherMap API and analyzed using Empirical Bayesian Kriging interpolation in ArcGIS Pro. LULC results revealed vegetation cover declination by 67.34%, bareland expansion by 102.73%, and water body surge by 4150% due to quarry-induced craters. The NDVI decreased from 0.064–0.408 to 0.030–0.406, and Land Surface Temperature (LST) increased from 29.23–40.72°C to 31.12–42.62°C. Air quality analysis showed that PM2.5 ranged from 4.91 to 10.34ug/m³ and PM10 from 10.24 to 17.03ug/m³, remaining consistently below their respective WHO annual thresholds (10ug/m³ and 20ug/m³, respectively). Proximity analysis using buffer zones (500m, 1000m, and 1500m) revealed significant human exposure, with 447 buildings identified within the 500m zone. Critically, this proximity indicates non-compliance with international benchmarks, such as the Code of Pollution Control (NEA Singapore) recommendation for a 3-kilometer protective buffer between quarries and residential areas. As part of the standard EIA framework, this study further recommends yearly environmental checks for environmental impact, teamwork with the government in city planning and safety zone control, quarry land restoration and recovery planning, and better community involvement and complaint systems. This study successfully integrated remote sensing and geospatial techniques to provide quantitative evidence of significant landscape transformation, vegetation loss, and thermal stress for EIA assessment for quarrying activities.

This study examines how governance influences environmental sustainability in Ghana’s mining supply chain, with particular emphasis on the strategic application of intelligence-led and community-oriented policing. Drawing on Institutional Theory and Routine Activity Theory (RAT), this study employed a cross-sectional design with 382 respondents from the regulatory and law enforcement sectors, as well as community leaders and residents of selected mining districts in Ghana. Findings from structural equation modelling (AMOS) and Hayes' PROCESS macro show that Institutional Coordination Practices (β = 0.322, p = 0.002) and Transparency and Accountability Practices (β = 0.290, p = 0.002) substantially contribute to improvements in environmental sustainability. Among the variables, Intelligence-Led Policing was the most robust positive predictor (β = 0.391, p = 0.001), thereby confirming the importance of an intelligence-based strategy in the enforcement of regulations on illegal mining. Furthermore, Community-Oriented Policing mediated the relationship between Institutional Coordination and environmental outcomes (indirect β = 0.110, p = 0.001). In addition, Community Trust Capital contributed to the Community-Oriented Policing and sustainability connection (interaction β = 0.066, p = 0.006), thus emphasizing the importance of trust in the community-police relationship. Considering that Regulatory Enforcement Capacity is statistically insignificant (p = 0.367) in conjunction with control variables, Community Trust Capital still positively contributes to the overall robustness of the model (β = 0.184, p = 0.005). This study theoretically reconceptualizes governance as a relational behavioural system whereby the environment is shaped by the synergetic alignment of institutional goals, community participation, and locally adaptive control. In practice, the results advocate the integration of Intelligence-Led Policing and Community-Oriented Policing within national mining policies, fostering interagency collaboration and building trust with communities to achieve sustainable mining. The model is proposed for replication in environments where enforcement resources are severely limited.

Coastal acidification—the near-shore manifestation of ocean acidification—remains far less constrained than open-ocean chemistry, especially in semi-enclosed systems such as Cape Cod Bay (CCB). As anthropogenic CO₂ emissions continue to rise, resolving local variability in carbonate chemistry has become increasingly important. Compared with the neighboring Gulf of Maine, CCB displays much greater fluctuations in parameters like in situ pHₜ, total alkalinity (TA), and dissolved inorganic carbon (DIC), driven by freshwater inputs, submarine groundwater discharge (SGD), and stronger biological and human influences. In this work, we construct predictive models for TA, DIC, and pH at 20 °C using multilinear regression and machine learning algorithms trained on in situ observations. These predictions are then used in CO2SYS to estimate pHₜ with very high accuracy (mean residual < 0.0001; standard deviation < 0.1). Using the modeled carbonate fields, we generate basin-wide maps of calcite and aragonite saturation states for the entire bay through spatial interpolation. Our results indicate that the inorganic carbon system of Cape Cod Bay is governed by the combined effects of seasonal air–sea CO₂ fluxes, terrestrial inputs, and water-mass retention, making it an acidification hotspot that differs markedly from the Gulf of Maine. Locally trained predictive models outperformed ESPER’s regional products, underscoring the importance of site-specific approaches. Together, these findings provide new perspectives on coastal carbon dynamics and establish a scalable framework for forecasting carbonate chemistry in other nearshore environments.

This work examines the generation and optimization of activated carbon from cactus biomass via chemical activation with hydrochloric acid (HCl) to assess its efficacy and sustainability as an adsorbent for removing methylene blue from aqueous solutions. The preparation procedure involved two primary steps: carbonization of the cactus biomass at a regulated temperature, followed by chemical activation with HCl to augment the material's porosity, surface area, and active functional groups. The resulting adsorbent was characterized and used in methylene blue adsorption experiments

A Box–Behnken experimental design was employed to optimize the process and assess the effects of critical operating factors. The effects of solution pH, initial dye concentration, and adsorbent dose, as well as their interactions, were systematically examined. Statistical analysis revealed that all parameters significantly influenced the adsorption capacity. The experimental data conformed well to a quadratic model, yielding a high coefficient of determination (R² = 0.97), thereby affirming the model's robustness and predictive accuracy. Under optimal conditions, the cactus-derived activated carbon exhibited exceptional methylene blue removal efficiency, indicating robust adsorption capacity.

To evaluate the environmental and economic advantages of the proposed adsorbent, the study conducted comparative analyses of precursor availability, energy requirements during carbonization, chemical consumption during activation, and estimated production cost per unit mass of activated carbon. Life-cycle considerations, including the renewability of cactus biomass and its reduced environmental footprint relative to conventional activated carbon derived from non-renewable sources, were also assessed. These methodological approaches helped quantify reductions in waste generation, energy input, and overall treatment cost.

These findings underscore the efficacy of cactus biomass as an economical, renewable precursor for the manufacture of activated carbon. The study emphasizes its environmental and economic advantages, suggesting its promising application in wastewater treatment processes for the removal of synthetic dyes and other persistent organic contaminants

This study represents the first assessment of heavy metal bioaccumulation in marine fish from the Andaman region, investigating the bioaccumulation of essential (Fe, Zn, Cu, Mn) and non-essential (Al, Cd, Pb, Ni) metals in five commercially important fish species (Cephalopholis sonnerati, Auxis rochei, Epinephelus bleekeri, Rastrelliger kanagurta, Nemipterus japonicus) from the Junglighat & Wandoor Fish Landing Centre, Port Blair, South Andaman. Tissue samples from gills, liver, muscle and intestine were analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to assess organ- and species-specific accumulation patterns. The liver emerged as the primary sink for most metals, particularly Fe, Cd and Pb, while gills accumulated Cu and Mn, and intestines showed elevated Zn and Al. Muscle consistently exhibited the lowest metal concentrations, confirming its safety for human consumption. Significant organ-specific differences were observed for most metals, except Cd, Pb, and Ni, with distinct metal profiles in detoxification (liver, gills) versus storage/digestive (intestine, muscle) organs. Correlation analyses indicated shared uptake pathways for Al with Mn, Fe, and Cu. This pioneering study establishes a critical baseline for metal bioaccumulation in the Andaman region, revealing low muscle metal levels that ensure food safety and highlighting the need for targeted monitoring of detoxification organs like the liver due to elevated Cd and Pb and also addressing research gaps and informing environmental monitoring and fisheries management.

Microplastics (MPs) have emerged as significant indicators of anthropogenic pressure and deteriorating water quality in riverine systems. This study investigates the interrelationship between microplastic abundance and key physico-chemical parameters of the Yamuna River to elucidate how hydrochemical conditions influence MP distribution along the Delhi stretch. Water samples were analyzed for pH, dissolved oxygen (DO), electrical conductivity (EC), total dissolved solids (TDSs), and salinity, and the correlations were assessed. Strong negative correlations between pH and both EC (r = –0.99) and TDS (r = –0.99) reveal that acidic conditions correspond to higher ionic concentrations, likely resulting from untreated industrial effluents and urban runoff. A positive correlation between pH and DO (r = 0.88) indicates relatively cleaner and photosynthetically active regions within the river. In contrast, MP abundance exhibited strong positive correlations with EC (r = 0.95) and TDS (r = 0.94), but negative correlations with pH (r = –0.96) and DO (r = –0.81), suggesting greater accumulation of MPs in low-oxygen, high-ionic-strength waters. A moderate positive correlation with salinity (r = 0.68) further suggests enhanced deposition of MPs in sediment-laden and low-flow zones. The results collectively demonstrate that microplastic occurrence in the Yamuna River is closely governed by hydrochemical dynamics, reflecting complex interactions between pollution inputs and physical transport processes. Thus, microplastics can serve as effective indicators of water quality degradation, underscoring the need for integrated monitoring frameworks that couple conventional hydrochemical assessments with emerging contaminant analyses for sustainable river restoration.

Phenolic compounds, secondary metabolites in the herb of the endemic species Satureja horvatii Šilić (Lamiaceae), exhibit antioxidant activity, highlighting the medicinal value of this species. Natural deep eutectic solvents (NADES) represent a new generation of environmentally friendly and sustainable solvents, developed in accordance with green chemistry principles. These solvents are gaining attention as alternatives to conventional solvents. This study aimed to assess the effect of various NADES, combined with the green microwave-assisted extraction (MAE), on the preliminary chemical composition and antioxidant potential of extracts from S. horvatii herb. The effectiveness of NADES was also evaluated in comparison with conventional solvents, including ethanol and water. Four types of NADES were prepared through a combined heating–stirring technique, employing choline chloride, lactic acid, malic acid, glucose, and glycerol as components, in appropriate molar ratios. Six extracts of S. horvatii were produced through MAE, utilizing NADES, ethanol, and water as extraction media. Extraction was conducted in three 5-second cycles. Spectrophotometric techniques were used to determine the total phenolic content (TPC) and the total flavonoid content (TFC) of the extracts. The antioxidant potential of the extracts was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and the cupric reducing antioxidant capacity (CUPRAC) assay. The glycerol–lactic acid NADES enabled the extraction of the highest TPC, while the choline chloride–lactic acid and glycerol–lactic acid NADES exhibited the strongest antioxidant activity in the CUPRAC assay. The application of the MAE–ethanol combination yielded extracts with the highest TFC and the most potent DPPH radical scavenging activity. Lactic acid-based NADES represent an efficient and sustainable alternative to conventional solvents, providing extracts with TPC, TFC, and antioxidant activity, comparable to or exceeding those of ethanol and water.

Acknowledgments: This work was supported by the Provincial Secretariat for Higher Education and Scientific Research, Province of Vojvodina (Grant No. 142-451-3474/2023).