Treatment processes for microplastics and nanoplastics in waters: State-of-the-art review

Ultrahigh-efficiency and synchronous removal of microplastics-tetracycline composite pollutants via S-scheme core-shell magnetic nanosphere

Composite pollution in aquatic environments has become a critical challenge, with emerging pollutants like antibiotics and microplastics (MPs) posing significant ecological risks. The interaction between antibiotics and MPs complicates treatment processes and underscores the need for targeted removal strategies. This study focused on a novel S-scheme core-shell magnetic nanosphere, Fe3O4@TiO2-C4N, combining TiO2 and C4N to form a heterojunction that enhances photocatalytic performance. The S-scheme heterojunction improves redox ability, enabling efficient degradation of composite pollutants under light irradiation. After 12 h reaction, Fe3O4@TiO2-C4N achieved 97.3 % removal for polyethylene (PE) MPs and 96.0 % removal for tetracycline (TC), surpassing existing TiO2-based catalysts. Moreover, Fe3O4@TiO2-C4N demonstrated excellent magnetic recyclability rate of 77.07 %, enabling easy catalyst recovery and reuse. Meanwhile, Fe3O4@TiO2-C4N outstands on TC removal at an optimal concentration (200 mg L-1). Notably, MPs in composite pollution scenarios showed higher removal rates than individual pollutants. This study highlights the powerful role of Fe3O4@TiO2-C4N as a promising photocatalyst for the joint degradation of multiple composite pollutants in aquatic environment, providing an innovative solution for addressing water pollution challenges. Furthermore, its real-world application potential is demonstrated by its efficient recovery, long-term stability, and compatibility with existing water treatment systems, paving the way for large-scale environmental remediation technologies.

Combining nanofiltration and electrooxidation for complete removal of nanoplastics from water

Nanoplastics (NPs) have emerged as significant water contaminants, attracting increasing attention due to their potential impacts on aquatic ecosystems and human health. In addressing the environmental and health hazards posed by NPs in water, this new study explores a combined nanofiltration (NF) and electrooxidation (EO) approach. The proposed process begins with NF to concentrate the NPs in the water, followed by EO to degrade the NPs in the NF rejection. The results indicated that the employed NF system could completely eliminate NPs at different transmembrane pressures and times. The study also highlighted the influence of NP concentrations on recovery rates, showing a reduction in recovery at higher concentrations. Moreover, following the NF process, the EO process was examined for its efficiency in removing NPs over time and at various initial NP concentrations. The results revealed that the most effective durations were 20, 30, and 40 min for NP concentrations of 10, 22.5, and 35 mg/L, respectively. As a kinetic study, the rate of NPs degradation by the EO process was modeled using Langmuir-Hinshelwood (L-H) as well as power law models. The comparison between the models' predictions and the experimental data demonstrated that the power law and L-H models had good predictability for NP concentrations exceeding 10 mg/L and 2 mg/L, respectively. At concentrations below the 2 mg/L, deviations from the model were observed, likely due to changes in the reaction mechanism. It can be concluded from these results that, at low concentrations, the surface reactions were no longer the rate-determining step.

Interactions between nanoplastics and Tetrahymena thermophila: Low toxicity vs. potential biodegradation

Nanoplastics (NPs) are prevalent throughout the environment and have raised growing environmental concerns. Although numerous studies have examined the toxicological aspects of NPs, few have investigated their environmental fate and behavior when affected by organisms other than bacteria or fungi. Planktonic ciliates are essential components of aquatic ecosystems and play important roles in decomposing organic matter and transferring energy from the microbial food web to higher trophic levels. To investigate the interplay between NPs and the ciliate Tetrahymena thermophila, we executed a sequence of feeding experiments utilizing 50 nm polystyrene nanoplastics (PS-NPs). In the presence of sufficient nutrition, exposure to PS-NPs (even at concentrations up to 500 mg/L) did not significantly inhibit growth in Tetrahymena thermophila, indicating only a mild toxic effect of PS-NPs. When ingested by T. thermophila, the PS-NPs are repackaged into aggregates with lysosomal components in the food vacuole and finally expelled as compacted "fecal pellets". This process modifies the physical attributes of PS-NPs, including their hydrophilicity, aggregability, and buoyancy, influencing their transportation, retention, deposition dynamics, and ultimately their bioavailability within the environment. A total of 73 proteins were identified from the fecal pellets, containing various hydrolases. Gel permeation chromatography (GPC), Fourier transform infrared (FTIR), and thermogravimetric analysis (TGA) were used to identify changes in molecular weights, functional groups, and thermal stabilities of PS-NP residues in fecal pellets. The results verified the degradation of PS-NPs during the passage through the T. thermophila cell.

Polystyrene nanoplastics: optimized removal using magnetic nano-adsorbent and toxicity assessment in zebrafish embryos

Purpose

The presence of microplastics (MPs) and nanoplastics (NPs) in aquatic ecosystems has raised serious environmental and health concerns. Polystyrene is one of the most abundant plastic polymers found in the environment. Polystyrene MPs/NPs have harmful implications for human health and their removal from the environment has become a serious challenge.

Methods

In this study, we investigated the adsorptive uptake of polystyrene nanoplastics (PS NPs) from aqueous solutions using fly ash-loaded magnetic nanoparticles (FAMNPs) as the magnetic nano-adsorbent. During the factor screening study, the adsorption process was studied as a function of four variables namely pH (5-10), adsorption time (30-120 min), amount of FAMNPs (0.01-0.04 g), and stirring speed (50-200 rpm). Central composite design (CCD) and response surface methodology (RSM) were employed to establish the relationship between the variables. Furthermore, toxicity assessments of PS NPs were checked on a zebrafish model, shedding light on its potential ecological effects.

Results

Two variables namely the pH and amount of FAMNPs significantly influenced the adsorption capacity of FAMNPs and were further optimized for subsequent analysis. The optimum operational readings proposed by the model were pH (8.5), and the amount of FAMNPs (0.03 g), resulting in a good adsorption capacity of 29.12 mg/g for PS NPs. The adequacy of the proposed model was evaluated by analysis of variance (ANOVA). Zebrafish embryos exposed to PS NPs revealed physical deformations such as pericardial edema and malformed notochord.

Conclusion

The study demonstrates the effectiveness of FAMNPs in the adsorption of PS NPs from aqueous solutions, with optimal conditions identified at pH 8.5 and 0.03 g of FAMNPs using RSM. The adequacy of the model was confirmed through ANOVA analysis. Toxicity assessments on zebrafish embryos exposed to PS NPs revealed significant mortality and physical deformations, highlighting the importance of PS NPs removal for environmental health.

Graphical Abstract

Insight into the removal of nanoplastics and microplastics by physical, chemical, and biological techniques

Plastic pollutants create health crises like physical damage to tissues, upset reproductive processes, altered behaviour, oxidative stress, neurological disorders, DNA damage, gene expression, and disrupt physiological functions, as the biosphere accumulates them inadvertently through the food web. Water resources have become the generic host of plastic wastes irrespective of their particle size, resulting in widespread distribution in aquatic environments. The pre-treatment step of the traditional water treatment process can easily remove coarse-sized plastic wastes. However, the fine plastic particles, with sizes ranging from nanometres to millimetres, are indifferent to the traditional water treatment. To address the escalating problems, the upgradation of different traditional physical, chemical, and biological remediation techniques offers a promising avenue for tackling tiny plastic particles from the water environment. Further, new techniques and hybrid incorporations to the existing water treatment techniques have been explored, specifically removing tiny plastic debris. A detailed understanding of the sources, fate, and impact of plastic wastes in the environment, as well as an evaluation of the above treatment techniques and their limitations and challenges, can only show the way for their upgradation, hybridization, and development of new techniques. This review paper provides a comprehensive overview of the current knowledge and techniques for the remediation of nanoplastics and microplastics.

Marine foams impede metabolic and behavioural traits in the rough periwinkle Littorina saxatilis

Foams are a ubiquitous feature of marine environments. They can have major economic, societal and ecological consequences through their accumulation on the shore. Despite their pervasive nature and evidence that stable foam deposits play a pivotal role in the ecology of soft shore and estuaries, very limited amounts of information are available on their contribution to the structure and function at play in rocky intertidal ecosystems. This study shows that the metabolic rate of the high-shore gastropod Littorina saxatilis is significantly higher in individuals exposed to foams. Behavioural assays conducted under laboratory-controlled conditions further show that this species detects foam-born infochemicals both indirectly or directly, hence rely on both airborne and contact chemosensory cues. L. saxatilis also actively avoid areas covered in foam, and increase their activity in the presence of foam. These observations are interpreted in terms of foam-induced increased metabolic stress and increases behavioural anxiety and vigilance. They are further discussed in relation to the occurrence of two phytoplankton species known to produce repellent and/or toxic compounds such as domoic acid and dimethylsulfoniopropionate, the diatom Pseudo-nitzschia multistriata and the haptophyte Phaeocystis globosa, with the latter occurring at unusually high density. Taken together, these results suggest that the accumulation of foams on intertidal rocky shores may have major implications on taxa relying on both airborne and contact chemosensory cues to navigate, find food and mating partners. Specifically, the observed increased behavioural activity coupled with increased metabolic demands may impact species fitness and highlight potentially large ecological consequences in rocky intertidal ecosystems characterized by strong hydrodynamism and elevated organic matter content leading to the presence of long-lived foam.

Microplastics in drinking water: A review on methods, occurrence, sources, and potential risks assessment

Microplastics in drinking water captured widespread attention following reports of widespread detection around the world. Concerns have been raised about the potential adverse effects of microplastics in drinking water on human health. Given the widespread interest in this research topic, there is an urgent need to compile existing data and assess current knowledge. This paper provides a systematic review of studies on microplastics in drinking water, their evidence, key findings, knowledge gaps, and research needs. The data collected show that microplastics are widespread in drinking water, with large variations in reported concentrations. Standardized methodologies of sampling and analysis are urgently needed. There were more fibrous and fragmented microplastics, with the majority being <10 μm in size and composed of polyester, polyethylene, polypropylene, and polystyrene. Little attention has been paid to the color of microplastics. More research is needed to understand the occurrence and transfer of microplastics throughout the water supply chain and the treatment efficiency of drinking water treatment plants (DWTPs). Methods capable of analyzing microplastics <10 μm and nanoplastics are urgently needed. Potential ecological assessment models for microplastics currently in use need to be improved to take into account the complexity and specificity of microplastics.

Coagulation properties of magnetic magnesium hydroxide for removal of microplastics in the presence of kaolin and humic acid

Microplastics (MPs) is one of the most concerned emerging pollutants in recent years. Its widespread distribution has been shown to have potentially adverse effects on human health and ecosystems. Therefore, in this study, magnetic magnesium hydroxide coagulant (MMHC) was prepared by adding Fe3O4 magnetic micron particles in the Mg(OH)2 generation process, and it was used with PAM, a polymer flocculant, to remove polyethylene microplastics (≤270 μm) from water by coagulation. The removal efficiency of microplastics by MMHC reached 87.1%, which was 14.7% higher than that of traditional magnesium hydroxide coagulant (MHC). However, the Zeta potential of MMHC was lower than that of MHC, only 17.3 mV. In addition, the surface morphology of MMHC showed bubble-like clusters. The effect of PAM adding time on the microplastic removal efficiency was investigated. The best adding time of non-ionic PAM was 15s before the slow mixing started. The removal efficiency of organic matter and suspended particles in water by MMHC was determined by turbidity, ultraviolet spectrophotometry and three-dimensional fluorescence. The maximum removal efficiency was 98.5% and 93.3%, respectively. With the increase of the concentration of humic acid and kaolin in water, the removal efficiency of microplastics was basically not affected. MMHC can be reused after recycle, but it was found that the electrical neutralization mechanism was affected due to the transformation of its Zeta potential, and the adsorption effect of humic acid and kaolin particles in water became worse, the removal efficiency of microplastics, turbidity and UV254 decreased to 20.2%, 17.5% and 30%, respectively.

Carbon nanoparticles fabricated microfilm: A potent filter for microplastics debased water

Microplastics were found to be the major pollutant across the globe. Plastic microbeads, like 0.5 mm, are very small and mainly used for exfoliation. The marine species cannot distinguish between their usual food and these microbeads. Microbeads have the potential to transfer up the food chain, which may lead to consumption by humans in the end. Activated carbon from inexpensive sources has greatly interested separation systems, especially in water treatment. In that view, carbon nanoparticles were produced, combined with polyvinylidene fluoride (PVDF) polymer, and used as a membrane to trap the microplastic particles. UV-Vis, FTIR, TEM, and powder X-ray diffraction (XRD) analysis confirmed the produced carbon nanoparticles. FT-RAMAN Spectroscopy studies, microbial viable cell count, and turbidity analysis followed the membrane preparation and post-treatment. The carbon nanoparticle fabricated nanofilm effectively eliminates the microbial count and microplastics and reduces the turbidity (0.13 NTU). This study confirms that the membrane effectively filters microplastics and other contaminants. Nowadays, nanofiltration technologies have been considered beneficial for eliminating microplastics to an efficiency of 95%. Further research is needed to determine a feasible low-cost, ecologically suitable, and effective solution to remove the microplastics in water.

Microplastics in Malaysia's Aquatic Environment: Current Overview and Future Perspectives

Microplastic pollution has adversely affected the aquatic ecosystem, living creatures, and human health. Several studies in Malaysia have provided baseline information on the existence of microplastics in surface water, ingestion by marine life and sediment. Also, humans are exposed to microplastic due to consumption of contaminated abiotic and biotic products, such as processed seafood. Nonetheless, knowledge is still scarce among Malaysian on the potential remediation and pollution management of microplastics, which poses a significant challenge to preserve a good environmental status. Green technologies also other alternative to mitigate the contamination of microplastics for sustainable future. Hence, this review aims to provide an overview of microplastic's occurrence, fate, and implications in Malaysia's aquatic environment. Detection of microplastics from the water surface, ingestion by aquatics, and sediment samples are highlighted. Available different treatment processes toward microplastic remediation are also discussed. Additionally, the potential challenges, current perspective for plastic management in Malaysia, as well as green strategies for reducing microplastic contamination are also put forward. The goal of this work is to improve the understanding of the seriousness of microplastic contamination in aquatic environments, thus encouraging key concerns that need to be investigated further.

Biosolids: The Trojan horse or the beautiful Helen for soil fertilization?

The simultaneous requirement to manage resources and wastes in more rational way has meant that many communities worldwide have begun to search for long-term alternative solutions. Reuse and recovery of biosolids is considered to be a constant solution of circular sustainability, as waste disposal without further reuse background like fertilizer is no longer an alternative to be promoted. There have been developed many treatment methods over the years for the stabilization and sanitization of biosolids. However, the literature concludes that none of them is fully integrated by meeting all the basic criteria. Each method has its Achilles heel, and the appropriateness of the method lies in what is the goal each time. There are conventional methods with positive reciprocity in terms of sustainability, reuse indicators and technological maturity, but have high risk of microorganisms' reappearance. New advanced sustainable technologies, such as cold plasma, need to be further studied to apply on a large scale. The reuse of biosolids as construction materials is also discussed in the context of circular economy. Biosolids reuse and management legislation frame need to be revised, as a directive adopted 30 years ago does not fully meet communities' current needs.

Occurrence, analysis of microplastics in sewage sludge and their fate during composting: A literature review

Microplastics (MP) are ubiquitous contaminants and their presence in sewage sludge has recently received attention as they may enter agro-ecosystems if sludge is used as organic soil amendment. Indeed, plastic particles (<5 mm) can be transported from wastewater and sewage sludge to the soil environment either directly within the plastic matrix or indirectly as adsorbed substances. In this paper, articles from 18 countries reporting the MP quantity and their characteristics in sewage sludge from wastewater treatment plants were reviewed and the MP concentration size and type were compared. The data show that MP abundance in sewage sludge ranged globally from 7.91 to 495 × 10³ particles kg^-1 with highest abundance of fiber shape and MP size of less than 500 μm. In this review, we summarized and discussed the methods most frequently used for extraction and characterization of MP in sewage sludge including organic matter removal, MP extraction; physical and morphological MP characterization and its chemical characterization for polymer identification. We also described the major factors potentially controlling the fate of MP during disposal strategies with particular focus on composting. We show that physical and microbiological factors are important for MP degradation during composting and suggest two remediation practices: (i) inoculation of the initial sludge with microbial plastic decomposers to remove MP from contaminated sewage sludge, and (ii) development of high temperature composting processes.

Elimination of microplastics from the aquatic milieu: A dream to achieve

Microplastics (MPs) have become a significant source of concern as they have emerged as a widespread pollutant that harms the aquatic environment. It has become an enormous challenge, having the capacity to biomagnify and eventually affect human health, biodiversity, aquatic animals, and the environment. This review provides in-depth knowledge of how MPs interact with different toxic organic chemicals, antibiotics, and heavy metals in the aquatic environment and its consequences. Membrane technologies like ultrafiltration (UF), nanofiltration (NF), microfiltration (MF), and dynamic membranes can be highly effective techniques for the removal of MPs. Also, hybrid membrane techniques like advanced oxidation processes (AOPs), membrane fouling, electrochemical processes, and adsorption processes can be incorporated for superior efficiency. The review also focuses on the reactor design and performance of several membrane-based filters and bioreactors to develop practical, feasible, and sustainable membrane technologies. The main aim of this work is to throw light on the alarming scenario of microplastic pollution in the aquatic milieu and strategies that can be adopted to tackle it.

Removal of microplastics and nanoplastics from urban waters: Separation and degradation

The omnipresent micro/nanoplastics (MPs/NPs) in urban waters arouse great public concern. To build a MP/NP-free urban water system, enormous efforts have been made to meet this goal via separating and degrading MPs/NPs in urban waters. Herein, we comprehensively review the recent developments in the separation and degradation of MPs/NPs in urban waters. Efficient MP/NP separation techniques, such as adsorption, coagulation/flocculation, flotation, filtration, and magnetic separation are first summarized. The influence of functional materials/reagents, properties of MPs/NPs, and aquatic chemistry on the separation efficiency is analyzed. Then, MP/NP degradation methods, including electrochemical degradation, advanced oxidation processes (AOPs), photodegradation, photocatalytic degradation, and biological degradation are detailed. Also, the effects of critical functional materials/organisms and operational parameters on degradation performance are discussed. At last, the current challenges and prospects in the separation, degradation, and further upcycling of MPs/NPs in urban waters are outlined. This review will potentially guide the development of next-generation technologies for MP/NP pollution control in urban waters.

Testing an Iron Oxide Nanoparticle-Based Method for Magnetic Separation of Nanoplastics and Microplastics from Water

Nanoplastic pollution is increasing worldwide and poses a threat to humans, animals, and ecological systems. High-throughput, reliable methods for the isolation and separation of NMPs from drinking water, wastewater, or environmental bodies of water are of interest. We investigated iron oxide nanoparticles (IONPs) with hydrophobic coatings to magnetize plastic particulate waste for removal. We produced and tested IONPs synthesized using air-free conditions and in atmospheric air, coated with several polydimethylsiloxane (PDMS)-based hydrophobic coatings. Particles were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), superconducting quantum interference device (SQUID) magnetometry, dynamic light scattering (DLS), X-ray diffraction (XRD) and zeta potential. The IONPs synthesized in air contained a higher percentage of the magnetic spinel phase and stronger magnetization. Binding and recovery of NMPs from both salt and freshwater samples was demonstrated. Specifically, we were able to remove 100% of particles in a range of sizes, from 2-5 mm, and nearly 90% of nanoplastic particles with a size range from 100 nm to 1000 nm using a simple 2-inch permanent NdFeB magnet. Magnetization of NMPs using IONPs is a viable method for separation from water samples for quantification, characterization, and purification and remediation of water.

Coral-inspired environmental durability aerogels for micron-size plastic particles removal in the aquatic environment

Removing microplastics (MPs) from water has been a huge challenge due to their inherent features including small size and high stability. In this research, inspired by the active adsorption and passive adhesion mechanisms of corals to MPs, a new strategy to fabricate polydopamine enhanced magnetic chitosan (PDA-MCS) aerogels was developed with a target to match the surface properties of MPs, achieving high MPs removal efficiency. PDA-MCS aerogels were highly efficient in adsorbing polyethylene terephthalate (PET) microplastics in water at pH values of 6-9, with a removal efficiency of up to 91.6%. Even after three recycles, PDA-MCS aerogels still displayed comparatively high removal efficiency (83.4%). Kinetic and isothermal experiments showed that the adsorption process was the result of electrostatic interactions and physical adhesion between aerogels and microplastics. Moreover, PDA-MCS aerogels maintained high removal efficiency under simulated environmental conditions, and the removal efficiency of PET, polyethylene (PE) and polystyrene (PS) microplastics in waters reached 97.3%, 94.6%, and 92.3%, respectively. Therefore, high-efficiency environmentally durable aerogels adsorbent materials have the potential for the removal of MPs from the aquatic environment.

Superhydrophobic 304 Stainless Steel Mesh for the Removal of High-Density Polyethylene Microplastics

Microplastics are a global issue that affects the environment, economy, as well as human health. Herein, we present a superhydrophobic 304 stainless steel mesh obtained by chemical etching followed by a liquid-phase deposition of lauric acid that can be used for microplastic removal. Field emission scanning electron microscopy (FE-SEM) and high-resolution X-ray photoelectron spectroscopy (HR-XPS), among other techniques, were used to identify the hierarchical structure and chemical composition of the surface. They revealed that iron laurate decreased the surface free energy. The 304 stainless steel mesh was superhydrophobic (169°) and superoleophilic (0°). Taking advantage of these wetting properties, we showed an innovative use of these superhydrophobic surfaces in the removal of microplastics. Additionally, we analyzed the removal efficiency from a surface and colloidal point of view that allowed us to explain and clarify why microplastics can also be removed by their wetting properties. The loss of a double electrostatic cloud between the microplastics and the predominance of van der Waals interactions in the organic phase promote the removal of these persistent pollutants from water.

Electrochemical degradation of nanoplastics in water: Analysis of the role of reactive oxygen species

Microplastics and nanoplastics (NPs) are emerging water contaminants which have recently gained lots of attention because of their effects on the aquatic systems and human life. Most of the previous works on the treatment of plastic pollution in water have been focused on microplastics and a very limited study has been performed on the NPs treatment. In this work, the role of main reactive oxygen species (ROSs) in the electrooxidation (EO) and electro-peroxidation (EO-H₂O₂) of NPs in water is investigated. In-situ generation of hydroxyl radicals (^•OH), persulfates (S₂O₈^2-), and hydrogen peroxide (H₂O₂) were performed using boron-doped diamond (BDD) as the anode, whereas titanium (in EO process) and carbon felt (CF, in EO-H₂O₂ process) were used as cathode. In the EO process, NPs were mainly oxidized by two types of ROSs on the BDD surface: (i) ^•OH from water discharge and (ii) SO₄^•- via S₂O₈^2- reaction with ^•OH. In EO-H₂O₂ process, NPs were additionally degraded by ^•OH formed from H₂O₂ decomposition as well as SO₄^•- generated from direct or indirect reactions with H₂O₂. Analysis of the degradation of NPs showed that EO-H₂O₂ process was around 2.6 times more effective than EO process. The optimum amount of NPs degradation efficiency of 86.8% was obtained using EO-H₂O₂ process at the current density of 36 mA·cm^-2, 0.03 M Na₂SO₄, pH of 2, and 40 min reaction time. In addition, 3D EEM fluorescence analysis confirmed the degradation of NPs. Finally, the economic analysis showed the treatment of NPs using EO-H₂O₂ process had an operating cost of 2.3 $US.m^-3, which was around 10 times less than the EO process. This study demonstrated that the in-situ generation of ROSs can significantly enhance the degradation of NPs in water.

Method for rapid biofilm cultivation on microplastics and investigation of its effect on the agglomeration and removal of microplastics using organosilanes

Since microplastics were recognized as a global environmental problem in the early 2000s, research began on possible solutions such as the removal of microplastics from waters. A novel and promising approach for this purpose is microplastics agglomeration-fixation using organosilanes. In this study, it is investigated how biofilm coverage of microplastics affects this process. The biofilm was grown on the microplastics by cultivating it for one week in a packed bed column operated with biologically treated municipal wastewater enriched with glucose. The biofilm was characterized using confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), and Fourier-Transform infrared spectroscopy (FT-IR). The results show a partial coverage of the microplastics with attached bacteria and extracellular polymeric substances (EPS) after 7 days of incubation. Comparing five polymer types (polyethylene, polypropylene, polyamide, polyester, and polyvinyl chloride) and three organosilanes, the biofilm coverage caused a reduced removal efficiency for all combinations tested as it changes the surface chemistry of the microplastics and therefore the interaction with the organosilanes tested in this study. Treatment of biofilm covered microplastic with ultrasound partly recovers the removal. However, the results underline the importance of simulated environmental exposure when performing experiments for microplastic removal.

Interactions of microplastics, antibiotics and antibiotic resistant genes within WWTPs

Microplastics (MPs) have been detected in atmosphere, soil, and water and have been characterized as contaminants of emerging concern. When exposed to these environments, MPs interact with the chemical compounds as well as the (micro)organisms inhabiting these ecosystems. This paper overviews the interactions and significant factors influencing the sorption process of antibiotics on MPs since distinct interactions are developed between MPs and antibiotics. The interplay between the MPs and the antibiotic resistant genes (ARGs) microbial hosts is presented and the important factors that may shape the plastisphere resistome are discussed. The interactions of MPs, antibiotics and antibiotic resistant bacteria (ARB) and ARGs in wastewater treatment plants (WWTPs) were discussed with the aim to provide a perspective for better understanding of the role of WWTPs in bringing together MPs, antibiotics and ARB/ARGs and further as release points of MPs carrying antibiotics, and ARB/ARGs.

Durable Superhydrophobic Coating for Efficient Microplastic Removal

The pollution caused by microplastics around the world is an increasingly significant issue that has to be tackled with different methods and technologies. Here, we report a straightforward and rapid process combining electrodeposition and electrophoresis to produce a durable superhydrophobic coating on an aluminum substrate (UNS A91070) that has a static contact angle (153°), sliding angle (1°), and contact angle hysteresis (1°). Field emission scanning electron microscopy and high-resolution transmission electron microscopy showed the presence of a hierarchical structure with nanolayers that were 70 nm thick. The chemical composition was also analyzed using attenuated total reflectance-Fourier transform infrared spectroscopy and high-resolution X-ray photoelectron spectroscopy, which revealed that the hierarchical structure was composed of zinc laurate (Zn(C11H20COO)2) that decreased the surface free energy of the system. Moreover, the coating showed high durability against abrasion caused by the P1200 SiC paper due to the presence of TiO2 particles in the upper layers as well as the homogeneous chemical composition of the hierarchical structure. Finally, taking advantage of the superoleophilic properties of superhydrophobic surfaces, the ability of the coating to remove high-density polyethylene microplastics from water was studied.

Current Developments in the Chemical Upcycling of Waste Plastics Using Alternative Energy Sources

The management of plastics waste is one of the most urgent and significant global problems now. Historically, waste plastics have been predominantly discarded, mechanically recycled, or incinerated for energy production. However, these approaches typically relied on thermal processes like conventional pyrolysis, which are energy-intensive and unsustainable. In this Minireview, some of the latest advances and future trends in the chemical upcycling of waste plastics by photocatalytic, electrolytic, and microwave-assisted pyrolysis processes are discussed as more environmentally friendly alternatives to conventional thermal reactions. We highlight how the transformation of different types of plastics waste by exploiting alternative energy sources can generate value-added products such as fuels (H₂ and other carbon-containing small molecules), chemical feedstocks, and newly functionalized polymers, which can contribute to a more sustainable and circular economy.