Micro- and nanoplastic pollution has emerged as a critical environmental issue over the past decades, with pervasive contamination detected in aquatic systems, soils, wildlife, and even human tissues. Despite growing concerns, research efforts have largely focused on model systems or localized studies, often yielding highly variable results due to seasonal fluctuations, differing sampling methodologies, and site-specific conditions. This variability complicates the assessment of contamination levels and hinders the development of effective mitigation strategies.

Our study provides a comprehensive evaluation of micro- and nanoplastic pollution in the freshwater systems of the Carpathian Basin, a region of significant ecological and economic importance in Central Europe. By analyzing water samples from multiple rivers across different seasons, we aim to establish a clearer understanding of contamination ranges, identify key sources, and assess spatial and temporal trends. Additionally, we evaluate the potential ecological and human health risks associated with plastic pollution in these waters.

Beyond environmental monitoring, this study also reviews policy and management solutions that could mitigate plastic pollution in the region. We discuss the effectiveness of existing regulatory frameworks, explore innovative waste management strategies, and highlight the need for regional cooperation to address transboundary contamination. By integrating scientific data with policy analysis, this work seeks to contribute to more informed decision-making and sustainable water resource management in the Carpathian Basin and beyond.

Nanotechnology is emerging as a transformative force in sustainable construction, advanced material development, and environmental health by enabling nanoscale modifications in building systems. Engineered nanomaterials significantly enhance mechanical performance, thermal insulation, and energy efficiency, contributing to reduced carbon emissions, optimized material utilization, and improved indoor environmental quality. In the post-pandemic context, nanotechnology has further demonstrated its relevance through antimicrobial coatings, photocatalytic surfaces, and nanoparticle-based air filtration technologies aimed at mitigating pathogenic transmission in built environments. However, the production and deployment of nanomaterials present considerable challenges, including high energy consumption, substantial manufacturing costs, and unresolved toxicological and ecotoxicological risks. Documented concerns include inhalation-related respiratory dysfunction, cardiovascular effects, and potential neurotoxicity, necessitating stringent exposure assessments and standardized regulatory oversight. Advances in green synthesis methods and continuous-flow microreactor technologies offer promising alternatives for scalable and environmentally sustainable production. A comprehensive life-cycle assessment is essential to evaluate long-term performance, occupational exposure, and end-of-life scenarios. Interdisciplinary collaboration between materials scientists, toxicologists, and urban health researchers is required to guide the safe integration of nanotechnologies. Embedding circular economy strategies, prioritizing low-impact manufacturing, and establishing harmonized international safety standards will facilitate the responsible application of nanotechnology in the transition toward energy-efficient, health-supportive, and ecologically sustainable urban systems.

Multilayer graphene oxide (mGO) was synthesized from the oxidation of graphite using a modified Hummers' method. Subsequently, mGO was functionalized with dimethyl sulfoxide (DMSO) and potassium thiocyanate to obtain the new thiol-functionalized multilayer graphene oxide (mGO-SH). Characterization analyses using Infrared Spectroscopy (FTIR), Raman Spectroscopy, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), and Thermogravimetric Analysis (TGA) were performed to unravell the properties of mGO and mGO-SH. Both materials were then evaluated as adsorbents for the organic contaminant furfural through a comparative approach. Batch studies on kinetics, equilibrium, thermodynamics, and adsorbent regeneration were conducted to investigate the affinity of mGO and mGO-SH for furfural. Initial adsorption assessment showed that graphene oxide was unable to adsorb furfural. After functionalizing mGO, it was found that the contaminant was adsorbed, and kinetic studies indicated that the system reached equilibrium after 5 minutes. The equilibrium adsorption capacity (q_e) was 636.93 mg.g⁻¹, and the kinetic constant k₂ was 0.01575 g.mg⁻¹.min⁻¹ for furfural. Moreover, the pseudo-second-order model best fit the experimental data. Equilibrium studies showed a maximum monolayer adsorption capacity of 722.12 mg.g⁻¹ for furfural, and the Langmuir–Freundlich isotherm provided the best fit for the adsorption in the evaluated systems. Thermodynamic experiments revealed that all systems were spontaneous [ΔGº < 0] and evidenced the physical nature of furfural adsorption by mGO-SH [ΔGº = -11.74 kJ.mol⁻¹]. Adsorbent recycling experiments showed that thiol-functionalized graphene oxide had a removal rate of over 40% after five cycles.

Due to their small size and high reactivity, ZnO nanoparticles (NPs) can increase yarrow yields and control worms, enhance the activity of mustard cells and improve their antioxidant capacity, and promote plant growth. Meanwhile, there are data showing that ZnO NPs may inhibit the root formation of plants toxic to wheat. Due to the wide variety of research methods, conditions, NPs synthesis and properties, it is impossible to fully analyze and predict the effects of NPs concentrations on plants.

This study explored the treatment of wheat seeds with different concentrations of engineered ZnO NPs with average particle sizes of 40 and 300 nm. After the treatment, we measured the germination energy and root/shoots length of young wheat seedlings.

The results showed that 40 nm ZnO NPs had a promoting effect on wheat seeds when the concentration of NPs was 1-100 mg per liter. At higher concentrations (100-1000 mg per liter), the inhibitory effect on wheat roots continued to increase. For 300 nm of ZnO, the promoting effect was smaller compared to that of 40 nm ZnO NPs. In contrast, the larger 300 nm ZnO NPs induced a consistently smaller promoting effect across the tested concentrations compared to the 40 nm particles, indicating that nanoparticle size played a critical role in determining biological activity and phytotoxicity thresholds. These findings underscore the necessity of precise size and concentration control in agricultural nanoparticle applications.

Nanotechnology offers promising solutions for the control of waterborne pathogens by enhancing disinfection treatments using specialized nanomaterials. This study explores whether coffee waste-based nanostructures (CNs) enhance water solar disinfection (SODIS) against Cryptosporidium parvum, a waterborne protozoan parasite that resists conventional treatments and is classified by the WHO as a reference pathogen. Coffee waste was carbonized at 600 °C for an hour, and CNs were obtained via pyrolysis and hydrogen peroxide treatment, followed by dialysis membrane removal. CNs were characterized by particle size and zeta potential. Quartz tubes containing several CNs concentrations (0.1, 0.4, 0.9, and 1.4 mg/mL) in distilled water were spiked with 2×10⁶ oocysts/mL of C. parvum and exposed to simulated solar radiation (40 W/m², 290–400 nm) at 40 °C under polyethylene terephthalate cover. Oocyst viability was assessed at 2, 4, and 6 hours through hsp70 mRNA quantification using reverse transcription qPCR with previous induction at 42 °C. After 6 hours, oocyst inactivation rates were 0.87±0.01, 1.71±0.06, 2.55±0.08, and 1.96±0.02 log reductions (LR) at CNs concentrations of 0.1, 0.4, 0.9, and 1.4 mg/mL, respectively, significantly higher than those observed in distilled water without CNs (0.60±0.09 LR). These findings highlight the improvement of the C. parvum inactivation by SODIS by using CNs, achieving ≥2 LR at a concentration of 0.9 mg/mL. The optimization of water treatment technologies could provide sustainable alternatives to conventional methods, addressing the challenges posed by resilient protozoan pathogens and contributing to better public health. At the same time, reusing coffee waste in a circular economy reduces environmental impact while promoting innovation.

Acknowledgments. This project was funded by the Autonomous Government of Galicia (grant ED431C 2021/26) and the European Union's Horizon 2020 research and innovation programme (grant 820718). S.D. was granted by a Doctoral Fellowship of the National Operational Programme Research and Innovation 2014-2020 (grant CCI2014IT16M2OP005).

The paper examines chitosan aspartate shell nanoparticles formed in situ in the process of counterion condensation using novel bioactive sol–gel precursors: silicon methyltriglycerolate (MeSi(OGly)₃), silicon dimethyldiglycerolate (Me₂Si(OGly)₂), silicon tetraglycerolate (Si(OGly)₄), and silicon tetrapolyethylene glycolate (Si[O(C₂H₄O)₉H]), as well as titanium tetrapolyethylene glycolate (Ti[O(C₂H₄O)₉H]). The diameter of nanoparticles in the freshly prepared dispersion increases in the series of sol–gel precursors Me₂Si(OGly)₂→Si[O(C₂H₄O)₉H]→MeSi(OGly)₃→Si(OGly)₄→Ti[O(C₂H₄O)₉H], with the lowest polydispersity for Si(OGly)₄ and the highest for Ti[O(C₂H₄O)₉H]. Si- or Ti- coated nanoparticles (excluding Me₂Si(OGly)₂) correspond to kinetically stable nanodispersions: the electrokinetic potential was within 35‒40 mV and the conductivity was 0.58‒0.73 mS/cm. Modification with Me₂Si(OGly)₂ led to abnormally high values of the ζ-potential of the nanoparticles and the conductivity of the system. It was found that dispersions of chitosan aspartate nanoparticles with a sol–gel shell exhibited surface activity. During two-year storage, Si(OGly)₄ -stabilized dispersions maintained stable size and stable electrochemical and surface properties. A slight decrease in particle size and an increase in polydispersity were observed during storage of the samples functionalized with the sol–gel precursor Si[O(C₂H₄O)₉H]; a significant decrease in the size and ζ-potential of particles were observed for Ti[O(C₂H₄O)₉H], while a significant increase in size, polydispersity, and surface tension were noted for MeSi(OGly)₃ and Me₂Si(OGly)₂. Silicon tetraglycerolate was identified as the optimal modifier for stable chitosan aspartate nanoparticles, with the resulting polysiloxane-stabilized particles exhibiting dual bioactivity: plant growth stimulation across taxa and antifungal action against soil pathogens.

Acknowledgment

This research was funded by a grant from the Russian Science Foundation No. 24-16-00172, https://rscf.ru/project/24-16-00172/.

Abstract:

Introduction:
Environmental pollution, especially of water resources with heavy metal ions, is of great concern. The removal of heavy metal ions from wastewater remains a challenge for scientific research. Polymer-based microsphere adsorbents are promising due to their design flexibility and chemical tunability, but classical synthesis methods often lack control over the morphology, porosity and wettability. In the current work, we introduce a new method for facile synthesis of polymer microspheres, namely Pickering emulsion polymerization technology (PemPTech) and utilize them as adsorbents for Cu(II) ion extraction and recovery from water.

Methods:
Polymer microspheres were synthesized by polymerization of w/o Pickering emulsions stabilized by surface functionalized silica nanoparticles with thiol groups. The water phase comprised of water and water soluble monomers, such as vinyl imidazole and methacrylic acid with varying amounts of ligands, crosslinkers or porogens. A homologous series of microspheres were prepared by systematically varying these components. Structural and morphological characterization was performed using FTIR and SEM, and the adsorption and desorption capacities of Cu(II) were evaluated via UV–vis spectrophotometry.

Results:
In this work, we highlight the versatility of the PemPTech. For example, by adjusting the chemical composition in terms of the relative ratio of the ligands, vinyl imidazole to methacrylic acid, we were able to fine tune the adsorption capacity of the adsorbent. The adsorbtion capacities were comparable or exceeding those of similar adsorbents obtained via alternative methods. Kinetic adsorbtion studies were performed, and isotherm profile were established for each adsorbent, indicating a good performance. The adsorbents were also tested for other divalent heavy metal ions.

Conclusions:
PEmPTech enables precise compositional and morphological tuning of polymer microspheres, offering a green and scalable route to high-performance adsorbents. This study provides critical insight into the design parameters governing metal ion uptake, laying the groundwork for applications in water purification and environmental remediation.

Over the last few decades, scientists have focused on chitosan modification [1]. Chitosan is a natural cationic polymer that is low-cost, non-toxic, biodegradable, and offers antimicrobial and adsorbent properties [2]. Moreover, chitosan provides two different functional groups, -NH₂ and -COOH, that create new chemical bonds with other smaller chemical compounds to improve mechanical properties and adsorption capacity. Many researchers have studied the modification of chitosan with dicarboxylic acids such as itaconic acid [3], citric acid[4], and malonic acid [5]. In this study, the modification of chitosan with tricarboxylic acid and succinic acid was tested. In the literature, numerous research articles refer to the chitosan modification with succinic anhydrate [6]^,[7]. However, succinic acid is less toxic (it is a GRAS-approved food additive by the FDA) [8] than succinic anhydrate, and this makes the new adsorbent Chitosan@Succinic acid more environmentally friendly. In this work, CS@SA was synthesized and characterized via FTIR and XRD techniques. Thereafter, CS@SA was investigated for the removal of diclofenac. Batch experiments concluded the effect of pH, kinetics, and isotherm studies.

Acknowledgment: We acknowledge support of this work by the project “Advanced Nanostructured Materials for Sustainable Growth: Green Energy Production/Storage, Energy Saving and Environmental Remediation” (TAEDR-0535821) which is implemented under the action “Flagship actions in interdisciplinary scientific fields with a special focus on the productive fabric” (ID 16618), Greece 2.0—National Recovery and Resilience Fund and funded by European Union NextGenerationEU.

Plastic nanoparticles (NPs) released from plastic pollution pervade aquatic ecosystems, raising concerns about their long-term toxic effects on aquatic organisms. The purpose of this study was to understand the sublethal toxicity of polyethylene nanoparticles (PENPs) and polypropylene nanoparticles (PPNPs) of the same size (a 50 nm diameter) in Hydra vulgaris. Hydras were exposed to increasing concentrations of the PENPs and PPNPs (0.3-10 mg/L) for 96 h at 20 ^oC. Toxicity was determined based on characteristic morphological changes and a gene expression analysis of genes involved in oxidative stress, DNA repair, protein salvaging and autophagy, and neural activity and regeneration. The data revealed that the PPNPs produced morphological changes (50% effect concentration EC50 = 7 mg/L), while the PENPs did not. Exposure to both nanoplastics produced changes in gene expression for all gene targets and at concentrations < 0.3 mg/L in some cases. The PPNPs generally produced stronger effects than the PENPs. The mode of action of these plastic polymers differed based on the intensity of the responses in oxidative stress (superoxide dismutase, catalase), DNA repair of oxidized DNA, regeneration, and circadian rhythms. In conclusion, both types of plastic nanoparticles produced effects at concentrations well below the appearance of morphological changes and at concentrations that can be found in highly contaminated environments. This study also show that hydra are very sensitive to plastic nanomaterials.

Magnesium and its alloys, as typical biodegradable metallic materials for medical applications, are successfully used in bone fixation devices, dental implants, and cardiovascular stents due to their high biocompatibility and controllable degradation characteristics. Accurate quantification of magnesium alloy degradation rates is paramount for establishing their optimal clinical dosage. Excessive implantation risks prolong implant persistence, concomitantly elevating the potential for localized inflammatory reactions. Conversely, insufficient dosage may significantly diminish therapeutic efficacy. Consequently, robust quantitative characterization of magnesium alloy degradation kinetics within the human physiological environment is indispensable for successful clinical translation. Currently, in vitro and in vivo methods are employed to assess their degradation, with in vitro electrochemical testing being the most common quantitative analysis. However, the simulated biological fluids used in modern in vitro systems fail to replicate the complex solid–liquid phase microenvironment of the human body, leading to significant discrepancies between laboratory data and actual in vivo degradation processes.

Given that natural polymer hydrogels derived from autochthonous plant sources exhibit microstructures and chemical compositions similar to human tissues, agar, pectin, and chitosan were selected as alternative approaches for evaluating the corrosion resistance of medical magnesium alloys. Conducted contact corrosion experiments and electrochemical studies demonstrated that the morphology of corrosion products and the degradation kinetics of magnesium alloys in gel electrolytes show significantly higher correlation with in vivo experimental data from mice compared to results obtained in traditional liquid media.

Moreover, due to the tunable properties of gel-based materials, it is possible to design electrolytes tailored to individual patient characteristics and implant localization by modifying the gel's structure and composition. This opens prospects for developing more accurate methods to assess biomaterial degradation under conditions that closely mimic physiological environments.