Microplastics, Volume 5, Issue 1 (March 2026) – 59 articles

Microplastics impact coral reefs due to their presence in the water column. This is the case of Ingeniero Reef, which borders the Veracruz-Boca del Rio metropolitan area. The objective of this study was to determine the presence of microplastics in the feeding zone adjacent to the corals located on Ingeniero Reef. Two sampling periods were conducted (dry and rainy seasons, 2023), obtaining water samples from the area adjacent to the corals and from the water column, with 20 per sampling period. In the laboratory, the microplastics were separated and classified by type, size, and color. A one-way ANOVA was performed to compare microplastic concentration between the two seasons and average size in corals and the water column, and the Bray–Curtis index was applied. A new technique for obtaining microplastics from coral reefs was developed. The concentration of microplastics varies according to the climatic season, with fibers being the dominant type. The size of microplastics can be a determining factor for corals. The development and application of standardized protocols for studying microplastics will allow for more reliable monitoring programs, yielding comparable results that will enable the assessment of the impact of this emerging pollutant. Full article

Accumulation of microplastics (MPs) in aqueous environments poses a serious ecological problem nowadays. MP particles are able to adsorb pollutants of different kinds and to transport them to living organisms, leading to biotoxicity. Hence, investigation of the adsorption of pollutants of different molecular weights onto MP particles is an important task. We employed the numerical Scheutjens–Fleer self-consistent field method to study (i) the formation of MP particles consisting of homopolymer macromolecules and (ii) the adsorption of pollutant homopolymer chains onto the MP particles. Under poor solvent conditions, the polymer macromolecules were shown to form MPs with a constant density inside the particle and with an interfacial layer at its periphery. The size of the MP particles and the thickness of the interfacial layer were controlled by the solvent quality. MP particles were shown to adsorb pollutant polymer chains from the surrounding liquid due to higher compatibility of the MP particle with the pollutant polymer chains as compared to the solvent. The amount of adsorbed polymer pollutant increased with the increase of its concentration in solution. Softer MP particles were shown to adsorb larger amounts of pollutants due to a broader interfacial layer. The conformational characteristics of the adsorbed polymer chains (trains, loops, and tails) were studied in detail. Full article

Plastic and microplastic (MP) pollution, along with alien species invasion, are of great concern for natural habitat preservation and human health, and are two important and concomitant likely causes for global biodiversity loss. In the present study, a Seabin, a device for buoyant waste collection in calm waters, was used to also characterize the waste collected in northernmost side of Lake Garda (Italy) in a period of very low anthropogenic pressure, the Winter season of 2024–2025. During the survey, 92.6 g of plastic was collected, i.e., a total of 540 pieces. About 6.9 mg of plastic per m³ of water was found, corresponding to about 0.04 plastic items per m³ and approximately 13 pieces of microplastics per day. Fourier-transform Infrared (FTIR) spectroscopy identification showed that the plastic was composed mainly of polyethylene (PE), polypropylene (PP), and polystyrene (PS). Microorganisms (Diatoms, Bacillariophyta) and microcrack formation with deposits of inorganic matter (mainly Si, Al, O, Ca) were also evidenced by SEM/EDX in all the observed aged MP. Qualitative evaluation of the captured biota highlighted the presence of at least five alien species, including invasive Dikerogammarus villosus. This study describes an easy and cost-effective novel methodology for simultaneously monitoring plastic waste and alien species presence in calm waters, which acts also as a mitigation tool for plastic pollution. The results could be of interest not only to policymakers and scientists, but also for public health and for environmental monitoring. Full article

Microplastics (MPs) are pervasive in marine ecosystems, yet the molecular mechanisms underlying their sublethal effects on zooplankton remain poorly understood. Here, we integrated transcriptomic screening with sequence homology analysis, structural modeling, and molecular dynamics (MD) simulations to examine protein–polymer interaction behavior in the tropical euphausiid Euphausia distinguenda. Transcriptomic analysis identified three MP-responsive proteins; two isoforms (P1, P2) were consistently downregulated following exposure to polyethylene microspheres, while a third candidate (P3) was upregulated but excluded from modeling due to insufficient homology. Structural models of P1 and P2 were generated using AlphaFold2 (ColabFold implementation) and evaluated through comparative structural analyses. MD simulations (100 ns) were conducted using representative polymer oligomers LDPE used as a polyethylene analog and PET and PC included as contrast polymers, which revealed pronounced protein-specific differences and polymer-dependent modulation of interaction stability. Nonbonded Lennard–Jones and Coulomb interaction energies indicated substantially greater intermolecular contact stabilization for P2 than for P1 across all polymers, with LDPE yielding the lowest mean polymer RMSD for P2, and PET for P1. Together, these results indicate that MP–protein interactions in E. distinguenda are consistent with a dominant role of protein structural coherence and dynamic surface compatibility rather than by static structural complementarity or specific binding affinity and provide a reproducible basis for exploring molecular-scale responses to MP exposure in ecologically relevant zooplankton. Full article

The environmental persistence of post-consumer plastics remains a critical challenge due to their chemical stability, the presence of additives, and prior environmental weathering. This study evaluates the partial biodegradation and chemical transformation of post-consumer low-density polyethylene (LDPE) and expanded polystyrene (EPS) by Tenebrio molitor larvae under uncontrolled environmental conditions. Four diets were tested, including LDPE+S and EPS+S (polymers supplemented with wheat bran), to assess the influence of a co-substrate on larval performance and polymer transformation. Fourier-transform infrared spectroscopy (FTIR) revealed the emergence of oxygen-containing functional groups (–OH and C=O) in the frass, which were absent or negligible in pristine materials, indicating oxidative modification of the polymer matrix. Gel permeation chromatography (GPC) revealed pronounced reductions in number-average molecular weight (Mn) and increased polydispersity for EPS-derived fractions, consistent with heterogeneous chain scission and partial depolymerization. For LDPE, GPC evidenced the formation of THF-soluble, low-molecular-weight polymer-derived fragments, indicating fragmentation despite the inability to quantify pristine LDPE due to its insolubility in the mobile phase. Gas chromatography–mass spectrometry (GC–MS) identified aromatic hydrocarbons, phthalate esters, organosiloxanes, and fatty acid derivatives, reflecting both degradation intermediates and migrated additives from post-consumer plastics. Together, these results provide integrated evidence that Tenebrio molitor can induce chemical transformation of post-consumer LDPE and EPS under non-controlled environmental conditions, offering mechanistic insight into a biologically mediated degradation pathway that is directly relevant to realistic plastic waste scenarios. Full article

While various disturbances in organisms have been reported following long-term oral exposure to small plastic particles (microplastic particles, MPs), the effects of acute, short-term encounters remain underrepresented in scientific research. In this study, adult male Wistar rats were orally gavaged with MPs of three different sizes (~41 µm, 70 µm, or 106 µm; dose: 35 mg/kg), originating from poly(ethylene terephthalate) (PET) bottles. Twenty-four hours post-exposure, the impact on overall health indicators, including food and water intake, sensorimotor function and clinical signs of toxicity, in addition to serum biochemical markers related to organ function and oxidative stress, were assessed. Although no overt sensorimotor impairments or visible toxicity signs were observed in all MPs-treated groups, several investigated biochemical parameters were significantly altered. Water intake was also modified, whereas reduced food intake occurred only in the group treated with median-sized MPs, suggesting that acute exposure to MPs can lead to early physiological and biochemical responses. The obtained results, compared to the data extracted by using machine-learning (ML) tools and GPT-5 model within the available literature, highlighted the importance of investigating the acute effects of MPs, which may precede or contribute to long-term health consequences. Full article

Background: Microplastics (MPs) are increasingly recognized as emerging contaminants in food products, including edible salt. Their presence raises concerns due to potential health impacts and the lack of regulatory frameworks in many countries, including Ecuador. This study represents the first systematic assessment of the occurrence of MPs in commercial salts marketed in Guayaquil and assesses public awareness and willingness to pay for contaminant-free salt. Methods: A total of 45 salt samples covering marine, table, rock, pink, and blue salt, were collected from supermarkets and local stores in Guayaquil. Microplastics were extracted through filtration and oxidative digestion and characterized morphologically under a stereomicroscope. Polymer composition was confirmed using Fourier-transform infrared spectroscopy (FTIR). Additionally, a digital survey was administered to 435 residents to gauge consumer awareness and perceptions. Results: Microplastics were detected in 100% of the salt samples analyzed. Rock and marine salts showed the highest concentrations (>900 items/Kg). Fibers, particularly blue ones, were the predominant morphology, and FTIR analysis identified polyethylene terephthalate (PET), polyamides, and natural fibers. Survey results indicated that only 51.5% of respondents had prior knowledge of microplastic contamination, but 85.7% expressed willingness to pay more for safer salt, and 95.4% supported regulatory measures. Full article

Microplastics (MPs) are a growing environmental concern due to their ubiquitous presence, especially in wastewater treatment plants (WWTPs), where they are transferred and accumulated in sludge and can be reintroduced into the environment through sludge reuse. The persistence of MPs highlights the need for effective and tailored treatment strategies to enhance their removal or management. This study investigates the effects and impacts of ozonation as a pretreatment method for sludge, followed by anaerobic digestion (AD), on low-density polyethylene (LDPE), polypropylene (PP), and polyamide 66 (PA(66)) MPs. Different ozone doses, ranging from 5 to 50 gO₃/gMPs, were tested in both deionized water and synthetic sludge. The study evaluated MPs degradation through mass variation measurements, Fourier Transform Infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Carbonyl Index (CI) analysis. Results showed that ozonation induced chemical modifications in MPs, increasing CI values and leading to the formation of oxygen-containing functional groups, particularly carbonyls. FTIR analysis confirmed the development of new absorption peaks at 1716 cm⁻¹ and 1710 cm⁻¹ for LDPE and PP, respectively, while PA(66) exhibited a shift in its carbonyl peak from 1739 cm⁻¹ to 1754 cm⁻¹. DSC analysis revealed a reduction in crystallinity for all tested polymers, suggesting increased structural disorder. However, no significant MPs mass reduction was observed, and AD did not further enhance MPs degradation. These findings highlight ozonation as a promising strategy for modifying MPs surface chemistry and potentially increasing their environmental degradability. Full article

Microplastics (MPs) have emerged as a growing environmental and food safety concern, with their presence widely reported in aquatic organisms and seafood. However, their occurrence in traditionally processed and fermented fish products remains unexplored. This study provides the first evidence of MP contamination in ethnic fermented fish products of Northeast India, namely Ngari, Hentak, and Shidal. MPs were analyzed for abundance, size distribution, morphology, color, and polymer composition using microscopic examination and Laser Raman Spectroscopy. The average MP abundance was 16.50 ± 5.18 MPs/g in Ngari, 15.73 ± 4.83 MPs/g in Shidal, and 20.50 ± 3.00 MPs/g in Hentak. Fibers and fragments were the dominant morphotypes across all products, with transparent and black particles occurring most frequently. Polymer characterization revealed polyethylene (PE) and polypropylene (PP) as the predominant polymers, followed by polyamide (PA), polyvinyl chloride (PVC), and polystyrene (PS). Size distribution analysis showed that MPs in the 101–300 µm range were most abundant in Ngari and Shidal, whereas smaller MPs (<50 µm) predominated in Hentak. The use of whole fish, including the gastrointestinal tract and gills, primary sites for MP accumulation, along with non-standardized fermentation practices and atmospheric deposition during retail, likely contributes to contamination. These findings highlight an overlooked route of human exposure to MPs through traditional fermented foods and underscore the need for improved processing practices and mitigation strategies to safeguard food safety and sustainability. Full article

Synthetic or plastic microfibers (MFs) are an emerging form of microplastic pollution in marine ecosystems, derived from textile degradation and weathering of fishing and aquaculture gear. Despite extensive evidence of MFs in marine organisms, the effects of MFs exposure on mussels remain poorly understood. This study investigated the impact of synthetic MFs on the mussel Mytilus galloprovincialis (Lamarck, 1819) over a semi-chronic time scale of 14 days, using MFs produced by grinding a microfiber cloth. Adult mussels were exposed to three MFs treatments: 8, 40, and 100 MFs/L, reflecting current and future scenarios in the Black Sea. Biomarkers assessed included lysosomal membrane stability (LMS), catalase (CAT), glutathione-S-transferase (GST), and acetylcholinesterase (AChE) activities. Significant lysosomal membrane destabilization (p < 0.05) occurred across all treatments. CAT activity in the digestive gland significantly decreased by 31.2%, 53.3%, and 62.1% at 8, 40, and 100 MFs/L, respectively. GST activity showed inhibition at 8 and 100 MFs/L and stimulation at 40 MFs/L. AChE activity decreased at 8 MFs/L but increased at higher concentrations. These results indicate that even environmentally relevant levels of synthetic MFs can alter cellular stability and enzymatic responses in mussels, suggesting potential ecological risks for marine bivalves. Full article

Plastic pollution is a global challenge. Despite plastics being complex chemical mixtures, hazard research has focused on particulate forms and the risks of plastic additives, especially for environmental organisms, remain poorly understood. This is a significant knowledge gap considering ubiquitous organismal exposure to plastics and the associated 16,000+ additives. The aim of this study was to provide ecotoxicological characterization of aqueous eluates of foamed plastic consumer products and propose a test battery for toxicity screening. To achieve this, the hazard of eluates of six randomly selected foamed plastic products was evaluated using aquatic decomposers, autotrophs and heterotrophs (Vibrio fischeri, Raphidocelis subcapitata, Lemna minor, Thamnocephalus platyurus, Heterocypris incongruens, Daphnia magna). Alarmingly, all plastic eluates affected the organisms, though toxicity varied among materials and species. Results showed that short-term contact may underestimate plastic eluate toxicity. To increase the environmental relevance of hazard assessment of foamed plastic eluates, harmonizing leachate preparation, using natural water and avoiding (excessive) filtration of eluates should be considered. OECD/ISO assays with R. subcapitata, H. incongruens and D. magna (96 h) can be recommended as a minimal sensitive battery for effective screening of plastic eluate toxicity. Full article

In recent years, microplastics (MPs) pollution in agricultural soils has increased markedly, largely due to the improper management of plastic mulch films used to improve crop growing conditions. In this context, the present study evaluated the use of biochar (BC) as a soil amendment for mulch-derived MPs-contaminated soils in a radish (Raphanus sativus L.) crop under greenhouse conditions. A pot experiment was established in soils contaminated with MPs (0.5% w/w) and amended with four BC rates (w/w): 0% (Control), 1% (BC1), 3% (BC3), and 5% (BC5). Soil physicochemical indicators were assessed, together with germination, leaf, and radish bulb growth parameters. The experiment was conducted under greenhouse conditions until the radishes reached commercial maturity. Most of the soil’s physicochemical indicators, such as hydrogen potential (pH), electrical conductivity (EC), water holding capacity (WHC), total organic carbon (TOC), organic matter (OM), total nitrogen (TN), ammonium (N–NH₄⁺) and nitrates (N–NO₃⁻), showed significant differences between treatments (p < 0.05), with the exception of the carbon-nitrogen ratio (C/N), which did not vary significantly (p ≥ 0.05). No significant differences were observed among treatments (p ≥ 0.05) for germination indicators. For leaf traits, dry biomass was significantly lower in BC1 than in the other treatments (p < 0.05). For radish bulb traits, fresh weight was significantly higher in BC3 (p < 0.05) compared with the other treatments. Similarly, total plant fresh weight showed significant differences among treatments, with BC3 exhibiting the highest value (p < 0.05). Overall, the BC3 treatment provided the greatest improvement in radish development in MPs-contaminated soil. However, further research involving different types of MPs, BCs, or other crop species is needed to more comprehensively assess the impact of BC on agricultural soils contaminated with MPs. Full article

Tyre and road wear particles (TRWPs) represent one of the most significant yet under-recognised sources of global microplastic pollution, contributing up to 28% of total emissions. Generated from the complex interaction between vehicle tyres and road surfaces, TRWPs are chemically diverse, morphologically heterogeneous, and environmentally persistent, making their detection and management particularly challenging. This review provides a critical synthesis of current knowledge on TRWP generation mechanisms, influenced by tyre composition, road types, and vehicle operation, and their environmental dispersion through air, stormwater runoff, snow removal, and roadside deposition. The chemical and physical complexity of TRWPs—often composed of rubber, bitumen, road paint, and heavy metals—necessitates multifaceted analytical approaches. We synthesise current advancements in TRWP identification techniques, including microscopy, micro-spectroscopy, and thermal desorption methods, while benchmarking their applicability using ISO standards. Furthermore, we develop an integrated framework synthesising current classification schemes, detection strategies, and regional policy responses for TRWP assessment. By identifying analytical and regulatory gaps, this review highlights the need for harmonised methodologies, improved analytical comparability, and coordinated policy interventions to address the environmental and health implications of TRWPs. Full article

Microplastics (<5 mm) are an increasing concern for environmental and human health, continuously detected in ecosystems worldwide and a variety of human tissues. While health effects remain unclear, experimental studies on microplastic particles have suggested adverse outcomes. Microplastic fibers, which shed from everyday items, are more toxic than particles and twice as prevalent, yet remain understudied. Microplastic studies vary widely and use various extraction techniques, with few validating recovery accuracy. These limited recovery studies primarily examine particles, raising concerns about the true abundance of microfibers. This study establishes baseline recovery rates of polyethylene terephthalate (PET) and polypropylene (PP) microfibers of varying lengths from formalin-fixed human cadaveric lung tissue. Following enzymatic and oxidative digestion, PET microfibers showed a recovery rate of 47%, while 87% of PP microfibers was recovered. Chemical alterations were assessed using laser direct infrared (LDIR) spectroscopy; optical microscopy and scanning electron microscopy (SEM) evaluated physical changes post-digestion. These findings provide insights into microfiber recovery, highlight potential over- and underestimations, and characterize the chemical and physical behavior of fibers within human tissue studies. Establishing accurate recovery methods is essential for advancing microfiber toxicology research and assessing potential health risks. Full article

Growing concern over the presence of microplastics in food has led to the development of numerous methods for their extraction and analysis. However, many of these methods are time-consuming and limited to specific food types. In this study, we present a novel and quick approach involving microwave-assisted acid extraction of microplastics from food, followed by Raman microscopy analysis. The method’s performance was evaluated through determination of its digestion efficiency, particle mass and number recovery, limit of detection (LOD), and the digestion protocol’s effect on polymer physicochemical characteristics. The extraction protocol achieved 99.74–100.01% digestion of four different food matrices within 2 h, with 81.4–110.7% mass and 80–108% number recoveries of added polymer particles, both being within the 80–120% range. Importantly, DSC, TGA, DLS and Raman analyses of added particle polymers showed no significant change in PE, PP and PTFE polymer structure, while some structural changes were found for PET and PMMA. This method’s good analytical performance, high throughput and suitability for quick digestion of several different food matrices make it a promising step towards reliable monitoring of microplastics in food. Full article

Microplastic (MP) pollution represents a significant environmental threat, impacting aquatic ecosystems and human health. This review examines critical elements of MP risk assessment, including exposure pathways, properties (polymer type, size, and shape), bioaccumulation, and ecological and health effects. It underscores the challenges of quantifying MP exposure and identifying pollutants, as well as gaps in understanding pollutant adsorption/desorption and biofilm impacts. MPs serve as carriers for organic pollutants, heavy metals, and chemical additives, potentially magnifying toxic effects. Emerging contaminants, such as pharmaceuticals, exacerbate these risks. Laboratory research is crucial to trace MPs through food chains from primary producers to humans and assess bioaccumulation and health impacts. Current assessments, however, are insufficient to provide comprehensive ecological risk evaluations. The review highlights the need for improved methodologies to assess MPs’ fate, trophic transfer, and long-term ecological effects. MPs often release harmful additives like plasticizers and flame retardants, necessitating studies to differentiate the impacts of polymers and additives. It emphasizes integrating MP toxicity data into risk models while fostering collaboration among scientists, policymakers, and communities. The paper advocates for a comprehensive framework combining advanced analytical methods and environmental monitoring to refine risk assessment models. These efforts aim to strengthen public awareness, support informed environmental policies, and promote sustainable practices to mitigate MP pollution impacts. Addressing these research gaps will significantly enhance the scientific understanding of MP risks and guide effective management strategies for environmental and human health protection. Full article

Micro- and nanoplastics (MNPs) are increasingly contaminating atmospheric particulates, yet their influence on PM_2.5 chemistry and toxicity remains poorly understood. This study investigates how secondary MNPs derived from common products (water bottles, coffee cups, and food plates) alter the properties of PM_2.5. We evaluated PM_2.5 leaching characteristics, oxidative potential, inflammatory activity, and bacterial-based cytological and metabolomic responses after 24 h of exposure to three MNP doses. MNPs markedly altered PM_2.5 chromophoric composition, with bottle-derived (PET) MNPs inducing the strongest increases in aromaticity, humification, and slope factor, followed by coffee cups (PLA/paper) and food plates (PP). These leaching shifts aligned with polymer-specific redox behaviors: bottle-derived MNPs enhanced antioxidant enrichment at high PM_2.5, whereas cup-derived MNPs produced the most pronounced protein-denaturation-based inflammatory activity. Escherichia coli assays showed non-linear growth responses, elevated reactive oxygen species, altered carbohydrate secretion, and membrane and protein perturbations that paralleled PM_2.5 chemical reactivity. FTIR metabolomic fingerprints revealed dose- and polymer-dependent disruptions in polysaccharide, lipid, and protein domains. Overall, the results demonstrate a mechanistic cascade in which MNP exposure reshapes PM_2.5 chemistry, amplifies oxidative and inflammatory potential, and culminates in measurable cytological and metabolic stress, with polymer identity (PET > PLA/paper > PP) as the dominant driver. Full article

Microplastic contamination in aquatic systems in urban areas is a cause for concern due to its ability to move from one location to another. This review investigates microplastic levels across different aquatic environments and its potential transport through the urban water cycle. This study explores current research on the presence and pathways of microplastics movement within the water cycle. It includes a comprehensive bibliometric analysis that identifies publication trends, dominant research themes, influential journals, and leading contributing countries. It covers microplastic occurrence across various natural environments, including marine, river, lake, and groundwater systems, and extends into the built environment such as water treatment facilities, wastewater systems, bottled water, and drinking water distribution networks. Results indicate that microplastic levels vary within the urban water cycle, with concentrations differing widely depending on geography, type of infrastructure, and sampling methodology. Despite some removal efficiency during treatment processes, residual microplastics remain prevalent in effluents and drinking water, posing potential ecological and health risks. This study identifies that some of the major challenges in determining the fate and transport of microplastics are inconsistent sampling methods, lack of standardization, and limited understanding of long-term impacts. This paper also identifies the necessity of coordinated global strategies that integrate policy, technology, and public awareness to mitigate microplastic contamination in urban water systems. Full article

The environmental degradation of plastics results not only in their mechanical fragmentation into microplastics (MPs), but also in polymer main-chain scission processes, causing continuous leaching and/or volatilization of low-molecular-weight species, often characterized by a hazardous profile. In this study, we investigated the hydrophilic photooxidation products (HyPOPs) generated upon UV irradiation of polystyrene (PS) and their transformation catalyzed by the enzyme laccase from the fungus Trametes versicolor. Through a series of enzymatic tests, the enzyme was found to promote coupling and conjugation reactions of HyPOPs into poorly soluble compounds mimicking natural humic acids. The enzymatic activity of laccase was studied under different experimental conditions to simulate those found in environmental matrices. Due to their oligomeric nature, these humic acid-like products of metabolic transformation by the fungal laccase are here nicknamed “mycoplastics” (i.e., polymers from fungi). This enzymatic biodegradation and biotransformation of xenobiotic HyPOPs highlights the role of specific enzymes as biological tools for environmental self-repair of polluted ecosystems. Moreover, it opens new perspectives for remediation strategies targeting elusive micro- and nanoplastics and their continuously generated hazardous molecular degradation by-products. Humic acid-like products resulting from laccase conversion of HyPOPs could contribute to the rehabilitation of contaminated sites by promoting the removal of toxic contaminants from soil and water. Full article

Plastics are highly persistent materials, and their environmental degradation can potentially exacerbate, rather than alleviate, pollution. The degradation of plastic materials releases toxic monomers and additives, such as bisphenol A (BPA), styrene, and dioxins, which are more reactive, harmful, and persistent than intact plastics. With half-lives ranging from weeks to decades, they bioaccumulate in food chains, disrupt ecosystems, and contribute to endocrine disruption and mutagenicity. Natural degradation pathways, like microbial metabolism and photodegradation, are slow and incomplete, often leaving toxic intermediates such as microplastics. Artificial strategies, including bioremediation and advanced oxidation processes (AOPs), show potential to address the problems of plastic pollution but face additional challenges like secondary pollution and scalability. Sustainable alternatives, including bioplastics and renewable non-plastic substitutes, present promising solutions. However, their widespread adoption is hindered by challenges such as high production costs and the need for specific conditions to facilitate degradation, necessitating further research and development. A combined approach of reducing plastic production, advancing recycling, and implementing effective remediation strategies is critical to mitigating plastic pollution’s long-term impacts on ecosystems, biodiversity, and human health. This review provides a critical analysis of the current understanding of plastic degradation processes and the toxic byproducts they generate. It highlights the paradox wherein increased degradability may exacerbate environmental hazards. Additionally, the review assesses innovative, eco-friendly alternatives designed to mitigate plastic pollution. Full article

The increasing presence of microplastics (MPs) in wastewater sludge raises concerns about their potential interference with anaerobic digestion (AD), a key process for energy recovery and sludge stabilization. This study investigated the impact of three common MPs, polystyrene (PS), polyethylene terephthalate (PET), and high-density polyethylene (HDPE), on the anaerobic degradation of a synthetic, rapidly biodegradable substrate under controlled batch conditions with the biomass from an anaerobic digester as inoculum. Biogas production, intermediate metabolic parameters, and microbial community dynamics were comprehensively assessed. The results showed a moderate inhibition of methane yield in the presence of MPs, with HDPE causing the most significant reduction (up to 24%) in biogas generation. PS exhibited the lowest impact, independent of the concentration added (0.5 and 1.0 g·L⁻¹). The microbial community structure demonstrated robustness, with Firmicutes and Bacteroidota maintaining dominance and methanogenic populations largely unaffected, except in the presence of HDPE. Raman spectroscopy indicated that none of the MPs underwent substantial structural degradation, but the subtle spectral shifts—particularly in PET—suggested the initial stages of physicochemical alteration. These findings offer new insights into the short-term resilience and adaptability of anaerobic microbiomes in the presence of MPs while revealing potential signals of process disruption. Full article

Microplastics (MPs) are persistent environmental pollutants of growing concern, threatening aquatic ecosystems worldwide. This study examined the influence of different pollution sources on the abundance, types, and polymer composition of MPs in two South African river systems, the uMsunduzi and Swartskop Rivers. Surface water and sediment samples were collected from sites impacted by industrial, wastewater, agricultural, and urban activities. Both rivers showed high MP contamination, with the highest concentrations detected in industrial and agricultural zones. Fibers dominated the particle shapes, while polyethylene (PE) and polypropylene (PP) were the most common polymers, alongside site-specific contaminants such as polytetrafluoroethylene (PTFE). Sediments generally contained higher MP concentrations and smaller particles than surface waters. These findings highlight the role of land use in shaping MP pollution profiles and the need for targeted mitigation strategies to protect freshwater systems. Full article

Greenhouse gas emissions associated with plastic production and disposal span the entire plastic life cycle, establishing a direct link between plastic pollution and climate change. This review demonstrates that micro- and nanoplastics (MNPs) also function as active components of climate feedback systems by disrupting marine trophic structures, altering microbial assemblages, and diminishing the ocean’s capacity for carbon storage. Synthesized evidence further indicates that environmental degradation of polymers enhances surface reactivity, facilitating the sorption and transport of persistent contaminants, including per- and polyfluoroalkyl substances (PFAS) and antibiotic-resistant bacteria (ARB). These interactions amplify combined risks to ecosystems and public health under climate change scenarios. This review also reveals that many existing remediation strategies prioritize waste reduction or physical removal while failing to account for contaminant–plastic–climate interactions, thereby limiting their long-term effectiveness. By integrating climate-related processes, polymer transformation, and contaminant dynamics, this review identifies critical knowledge gaps and underscores the need for mitigation strategies that jointly address plastic pollution, climate feedbacks, and emerging public health threats. Full article

This review synthesizes research on mechanisms of microplastic-induced mitochondrial damage, focusing on oxidative stress and inflammation to address the mechanistic pathways linking microplastic exposure to mitochondrial dysfunction and cellular toxicity. Analysis of diverse in vitro and in vivo studies across aquatic, terrestrial, and mammalian systems was conducted, emphasizing molecular, cellular, and functional mitochondrial parameters. Findings reveal consistent microplastic-induced reactive oxygen species generation, disrupting mitochondrial membrane potential and bioenergetics, with smaller and aged particles exerting greater toxicity. Inflammatory signalling via NF-κB, the NLRP3 inflammasome, and immune cell necroptosis is closely associated with oxidative stress, forming a feedback loop that exacerbates mitochondrial impairment. Molecular mechanisms implicate endocytic uptake pathways, mitochondrial calcium dysregulation, and apoptosis-related cascades, though causal validation remains limited. The interplay between oxidative stress and inflammation emerges as a central driver of mitochondrial damage across models. These integrated insights highlight the critical influence of microplastic physicochemical properties and biological context on mitochondrial and inflammatory responses. The findings inform future mechanistic research and underscore the need for standardized models to assess microplastic toxicity, advancing understanding of environmental and human health risks associated with microplastic pollution. Full article

The increasing production and accumulation of plastic waste, coupled with insufficient recycling practices, contribute to the growing presence of plastic in the environment. Nanoplastic particles are of particular concern, as they pose greater (health and environmental) risks and exhibit wider dispersion compared to macroplastics. The blood–brain barrier may be exposed to nanoplastics present in the blood, which could affect its functionality or even pass through and damage the central nervous system. This study examined the effects of polystyrene (PS) nanoparticles with different chemical surface modifications (pristine, carboxylated, aminated) and sizes (50 nm and 100 nm) on cells of the neurovascular unit (NVU): human brain endothelial cells, astrocytes, and pericytes. Results indicated that only high concentrations of nanoparticles (100 μg/mL and 300 μg/mL) applied for 48 h decreased cell viability and barrier integrity significantly. Specifically, 50 nm carboxylated PS particles reduced barrier integrity and altered tight junction gene expression substantially. Fluorescent labelling of the investigated particles enabled to confirm their uptake by all tested cell types of the NVU, but also highlighted that the labelling changes the particles’ properties. Furthermore, cell culture medium-dependent particle agglomeration and increase of size were inversely correlated with cellular internalisation, which has to be considered for future risk assessments. Full article

Microplastics (MPs) have been detected in aquatic environments worldwide; however, freshwater systems remain underexplored. MPs’ presence has not been reported yet in the Río Bravo/Grande at the Mexico–United States border. In 2022 and 2023, water (30 L) and sediment (~500 g) samples were collected at the river along the El Paso (U.S.)–Juárez (Mexico) municipalities. Water and sediment were digested using H₂O₂ or NaOH to isolate (CaCl₂), dye (Nile Red), quantify, and classify MPs by fluorescence microscopy. The number of microparticles detected in water and sediment ranged from 0.4 to 17 particles/L and 2.8 × 10³–1.0 × 10⁴ particles/kg, respectively. Similar concentrations of microparticles were estimated in water among sampled sites (ANOVA) in 2022 (p = 0.432, α = 0.05) and 2023 (p = 0.255, α = 0.05), but there were differences in sediments (2022, p < 0.01; 2023, p = 0.032. α = 0.05). Fibres, fragments, and films, with sizes ranging from 12.62 to 4282.25 µm, were found in the samples. Fibres were the most abundant shape in water (71.94%) and sediments (91.07%). MP concentrations varied in water and sediments in both years. The data generated by this study provide new insights into feasible methods for MP detection and its presence in the Río Bravo/Grande. Full article

Background: Nano- and microplastics (N/MPs) are widespread pollutants in aquatic ecosystems and may interfere with the physiology of diatoms. However, the underlying molecular mechanisms remain poorly understood. Methods: Cultures of the diatom species Skeletonema marinoi, a key contributor to marine primary production and biogeochemical cycles, were exposed for 10 days to polyethylene (PE) N/MPs (25 and 75 µg/mL). Growth, morphology, and cell viability were monitored, while gene expression of stress, inflammation, programmed cell death (PCD), and extracellular polymeric substance (EPS) biosynthesis markers was assessed by RT-qPCR. Results: Growth was not significantly affected. Gene expression showed biphasic regulation of antioxidant enzymes, induction of HSP70/90, transient modulation of prostaglandin-related genes, and dose- and time-dependent activation of PCD markers. Selected CAZymes possibly involved in EPS synthesis were downregulated at early stages, suggesting impaired aggregation potential. Conclusions: Exposure to PE N/MPs elicited subtle yet multifaceted effects in S. marinoi, including oxidative stress, inflammatory-like responses, modulation of EPS pathways, and PCD activation. Despite apparent growth resilience, the molecular alterations observed may impact bloom dynamics and carbon export. Full article

Synthetic plastics are polymers that are largely produced worldwide, impacting ecosystems and human health. Microplastics are produced from fragmentation and degradation of larger plastics, as a consequence of environmental factors. Low-density polyethylene (LDPE) and polypropylene (PP) are plastic polymers acting as environmental hazards. Challenges in effective plastic waste management include sustainable and environmentally responsible approaches like microbial degradation. In this work, a shotgun metagenomic approach has been applied to analyze the response of the microorganisms living on plastic surfaces (plastispheres) of LDPE and PP to biodeterioration of these plastics (BioProject-NCBI, PRJNA1378224). Low-density polyethylene and polypropylene materials were collected from a waste landfill of intensive greenhouse agriculture. A further functional analysis supported putative roles of enzymes that could be involved in the initial steps of biodeterioration of LDPE and PP, including sarcosine oxidases; bromo- and chloro-peroxidases; cytochrome P450 and alkane monooxygenases; and multicopper oxidases. A CheckM analysis of genes that code for these oxidative enzymes revealed that they were mainly from the bacterial Phyllobacterium genus (Rhizobiaceae family) and, in less abundance, from the archaeon Methanoculleus genus (Methanoculleaceae family). This study supports putative roles of sarcosine oxidases and bromoperoxidases, and other relevant enzymes, in bacterial and archaeal LDPE and PP biodeterioration, highlighting the genomic potential of the microbiomes under study in biodeterioration of these synthetic plastics. Full article

Micro- and nanoplastics represent ubiquitous environmental contaminants with emerging concerns regarding their impact on human health. The gastrointestinal tract is the primary site of contact, where micro- and nanoplastics may interact with the intestinal epithelium, potentially disrupting barrier integrity, altering microbiota composition, and triggering inflammatory or oxidative stress responses. Moreover, variability in particle size, shape, chemical composition, and surface modifications adds complexity to assessing their health impact. Findings remain inconsistent, and the mechanisms of toxicity are not yet fully elucidated. This study developed a tri-culture in vitro intestinal barrier model incorporating Caco-2 enterocytes, HT29-MTX mucus-secreting cells, and Raji B-induced M-like cells to mimic the structural and functional features of the human gut epithelium. Polystyrene beads of different sizes (40 nm and 200 nm) and surface functionalization (carboxylated and aminated) were characterized and exposed to the model to examine their effects on barrier integrity, cellular uptake, and cytotoxicity. The results showed that size and surface chemistry play key roles in particle interaction dynamics with the intestinal barrier, affecting cellular internalization and toxicological outcomes. This validated in vitro model provides a valuable tool for investigating micro- and nanoplastic behavior upon oral exposure, contributing to more accurate health risk assessments associated with plastic pollution. Full article

Saltmarshes have emerged as important sinks for microplastic (MP) pollution, yet little is known about the long-term accumulation and retention mechanisms of MPs in these environments. This study presents the first chronological record of MPs in Mediterranean saltmarsh sediments, using sediment cores dated via a combination of AMS radiocarbon (¹⁴C) and radionuclide (²¹⁰Pb, ¹³⁷Cs, ²⁴¹Am) from two saltmarshes located on the Adriatic Sea coast of Croatia (Blace and Jadrtovac). MPs were extracted and analysed across core depths and assessed in relation to geochemical parameters (organic matter (OM), carbonates, organic carbon (C-org), total nitrogen (TN), phosphorus (P) forms’ content, and grain size distribution). Results show that MPs first appear in sediments dated to 1950 in Jadrtovac and post-1960 in Blace, with concentrations increasing markedly in more recent surface layers. Jadrtovac exhibited higher MP concentrations (up to 0.5 MPs g⁻¹), dominated by fibres (86%) associated with urban and maritime sources, while Blace showed lower concentrations, dominated by fragments (60%), likely from localised sources such as agriculture or single-use packaging. Polymer analysis confirmed contrasting source profiles, with rayon and cellophane dominating in Jadrtovac, and polypropylene and olefin in Blace. MPs positively correlated with OM, C-org, P, TN and sand content, and negatively with clay and carbonate content. Principal component analysis (PCA) confirmed that MPs were associated with organic-rich, sandy sediments. These findings demonstrate that OM composition and sediment texture significantly influence MP retention and highlight the role of saltmarshes as long-term archives of plastic pollution in low-energy coastal settings. Full article