Microplastics

Plastic pollution is a growing concern in urban estuarine environments, where hydrodynamic conditions and structural features of vegetated habitats can promote the interception and accumulation of plastic debris. This study evaluated the coconut-fiber matrix of a mangrove-based floating island as a passive retention substrate for plastic pellets and smaller plastic particles under real field conditions in the Estero Salado, Guayaquil, Ecuador. The system consisted of three connected floating modules containing coconut fiber and 27 mangrove propagules and was originally developed to support mangrove establishment and local phytoremediation. Following approximately one month of estuarine exposure, the floating structure remained stable and plastic particles were visibly retained within the coconut-fiber substrate. A total of 300 visible plastic particles were recovered, of which 40 were randomly selected for morphological and ATR-FTIR characterization. Pellet-like particles represented 72.5% of the analyzed subset, and polymer analysis identified polyethylene (PE) in 87.5% and polypropylene (PP) in 12.5% of the characterized visible particles. Smaller retained particles were additionally recovered from coconut-fiber subsamples using saturated NaCl flotation, membrane filtration, stereomicroscopy, and FTIR microspectroscopy. Spectroscopic analysis provided evidence of synthetic microplastics, including spectra associated with PET and LLDPE, together with a separate fraction of cellulosic fiber-like materials associated with cotton, linen, and regenerated cellulose (rayon). Overall, the results demonstrate that the coconut-fiber matrix performed an additional function beyond its original role as a planting substrate by acting as a retrievable passive interception matrix for plastic particles under urban estuarine exposure. These findings support the further development of coconut-fiber-based floating systems for plastic interception while providing a basis for future quantitative assessments of retention performance. Full article

Plastic pollution remains one of the most pressing environmental challenges of the twenty-first century. Global production reached 413.8 million tons in 2023 and 430.9 million tons in 2024, while annual post-consumer waste continues to approach 300 million tons. Conventional mechanical and chemical recycling routes remain limited in scale, efficiency, and applicability to mixed or contaminated streams. Microbial systems that enzymatically depolymerize synthetic polymers can, for hydrolyzable polyesters, release monomers under mild conditions and thereby support biological recycling. This review synthesizes the engineering of microbial systems for plastic depolymerization and monomer recovery, progressing from natural degraders and plastisphere communities through the redesign of enzymes and metabolic pathways to synthetic consortia and early industrial translation. PET hydrolases such as LCCICCG and TurboPETase achieve 90–98% conversion of pretreated, amorphized PET under high-solid loadings. Equivalent monomer recovery from untreated high-molecular-weight polyolefins has not been demonstrated. Bibliometric analyses document a sharp acceleration in research output after the 2016 discovery of Ideonella sakaiensis. Limitations in catalytic rate, substrate scope, assay standardization, environmental relevance, and process scalability are examined, and a framework is set out that links plastisphere colonization to engineered monomer recovery without equating surface enrichment or mass loss with complete biodegradation. Engineered microbial platforms can contribute to a circular plastics economy only if laboratory advances are validated under industrially and environmentally realistic conditions. Full article

This perspective examines the interactions among microplastics (MPs), emerging contaminants (ECs), climate change, and extreme hydrological events. Droughts, water scarcity, heatwaves, intense rainfall, and floods can alter the occurrence, mobilisation, transport, fate, and risks of MPs and associated ECs across water, soil, and groundwater systems. The analysis focuses on the context-dependent potential of MPs to act as vectors of ECs, soil–water interactions, and the potential influence of MPs on greenhouse gas (GHG) emissions. When these stressors co-occur, their combined effects may be additive, synergistic, or antagonistic. Accordingly, the “perfect storm” framing is used here to describe the potential for mutually reinforcing and cascading risks rather than to imply that synergy occurs universally. An integrated perspective therefore helps anticipate worst-case scenarios and move beyond the fragmented assessment of individual stressors. This paper discusses sustainable mitigation and adaptation strategies, including advanced wastewater treatment, water reuse, climate-resilient water management, infrastructure adapted to increasing hydrological variability, climate-smart agriculture, and safer alternatives to conventional plastics and chemicals. Effective implementation combines technological innovation with monitoring, governance, policy action, and public awareness. By framing the microplastics–contaminants–water–soil–climate nexus as an interconnected sustainability challenge, this work aims to support environmental resilience and progress toward the Sustainable Development Goals. Full article

Microplastics are increasingly recognized as emerging contaminants with potential toxicological effects on aquatic organisms. Among widely used industrial polymers, poly(methyl methacrylate) (PMMA) has been detected in environmental matrices, raising concerns regarding its biological impacts. This study evaluated the developmental toxicity of 40 µm spherical PMMA microplastics in zebrafish (Danio rerio) using a standardized early-life stage exposure (3 hpf–6 dpf). Before exposure, particles were physicochemically characterized by Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), and micro-Raman spectroscopy (µRaman). Embryos were exposed to nominal concentrations ranging from 0.5 to 20 mg/L, and endpoints including survival, hatching rate, spontaneous movements, heart rate, morphology, and locomotor activity were assessed. PMMA exposure did not induce significant mortality or morphological abnormalities at any tested concentration. However, significant sublethal effects were observed, including accelerated hatching at 20 mg/L and increased heart rate across exposure groups, further supported by a positive concentration–response trend across vessel-level values, indicating altered developmental timing and cardiovascular function. These findings demonstrate that PMMA microplastics, despite low acute toxicity, can induce early physiological disturbances in a vertebrate model. The results highlight the importance of incorporating sensitive functional endpoints into hazard assessment frameworks and contribute to a more comprehensive evaluation of the environmental risks associated with microplastics traditionally considered to have low intrinsic reactivity. Full article

Microplastic pollution has become a major concern for the environment in freshwater ecosystems due to its persistence, distribution, and impacts. However, research about microplastic pollution in the Illinois portion of the Mississippi River and its tributaries is still limited. This research examined the occurrence, geographical distribution, properties, and potential sources of microplastics in the Mississippi River and its major tributaries in Illinois. Surface water samples from 24 locations were collected and examined by stereomicroscopy to detect and quantify microplastics. The relationships between microplastic levels and physicochemical and land cover variables were examined using Spearman’s rank correlation. Microplastics were identified at every sampling site, with concentrations ranging from 4.5 to 76 particles per liter (average: 25.95 ± 18.15 particles/L), and fibers comprised over 71% of the total particles. Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) analysis identified four types of polymers: nylon, polystyrene, polypropylene, and high-density polyethylene. Microplastic levels exhibited a negative correlation with dissolved oxygen (ρ = −0.617) and a direct correlation with pH (ρ = 0.500). The results include fundamental data about microplastic pollution at specific sites throughout the Illinois portion of the Mississippi River and emphasize possible correlations between microplastic levels, adjacent land cover, and water quality parameters. Full article

The widespread presence of microplastics (MPs) and associated plastic-derived compounds, bisphenols (BPs), in the environment—originating from plastic production or adsorption of environmental pollutants—results in unavoidable human exposure. Therefore, assessing their occurrence in human biological samples is essential for understanding potential health risks. In this study, pyrolysis gas chromatography–mass spectrometry was used to analyse human intraocular fluids—aqueous humour (AH) and vitreous humour (VH)—to identify 11 microplastic polymer clusters. A method based on dansyl chloride derivatisation combined with ultra-performance liquid chromatography–tandem mass spectrometry was employed to screen for five bisphenols (BPs) in blood serum collected from the same patients. Potential MPs isolated from ocular samples were qualitatively assessed by stereomicroscopy. The number of particles ranged from 14 to 69 per gram in AH and from 21 to 34 per gram in VH. Among AH samples, the most frequently detected polymer clusters were C-PVC, C-PMMA, C-PET, and C-PP, with average levels ranging from 0.41 to 0.84 µg/g. The three VH samples contained only C-PMMA, with an average concentration of 0.55 ± 0.12 µg/g. Polymers such as C-PA66 (0.30 ± 0.21 µg/g) and C-PA6 (0.15 ± 0.44 µg/g) were occasionally observed in AH. Analysis of 13 human serum samples demonstrated exposure to bisphenol A (BPA; 4.05–5.18 ng/mL) and bisphenol AF (BPAF; 2.13–4.54 ng/mL), but no clear correlation was observed between serum BP levels and intraocular MPs within the limitations of the present dataset. These findings suggest the presence of MPs and BPs in human biological samples; however, the results should be interpreted with caution owing to potential background contamination and the pilot nature of the study. Full article

Agricultural soils have been identified as significant sinks for plastic waste from mulch films, which in turn can reach aquatic ecosystems. As an alternative to conventional materials, there has been growing interest in biodegradable mulch films, but their environmental behavior and ecotoxicological effects are not yet fully established. In this study, the effects of residues from a conventional mulch film and a biodegradable mulch film on model organisms representative of edaphic (Hordeum vulgare and Cucurbita maxima) and aquatic (Paracentrotus lividus) ecosystems were evaluated. During this study, the residues of the mulches in seawater were also analyzed, considering natural aging conditions, using pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS). The results of the ecotoxicological tests showed that the residues of both types of mulch films did not generate any significant adverse effects on the selected terrestrial and marine bioindicators in the two end-of-life scenarios, with the exception of the residues of conventional mulch, unaged and aged for one month, at medium-high concentrations from an environmental point of view on P. lividus. The natural weathering assay in a marine environment showed that residues from conventional mulch film remained essentially unaltered, with similar concentrations detected throughout the 12-month exposure period. In contrast, the biodegradable mulch film exhibited significant degradation from the initial time point, reaching concentrations below the analytical detection limit after the first month. Full article

The plastisphere critically modulates interactions among microplastics (MPs), biofilms, and trace metals under environmentally realistic conditions, governing the interfacial reactivity of plastisphere-coated microplastics. Here, we investigated cobalt (Co) adsorption onto large polypropylene (PP) primary microplastics (~4 mm) exposed for 28 days in a flow-through riverine mesocosm across a gradient of Co concentrations (0–60 µg·L⁻¹). A multi-technique analytical approach was employed, combining inductively coupled plasma mass spectrometry (ICP-MS), laser ablation ICP-MS (LA-ICP-MS), quantitative PCR (qPCR), and scanning electron microscopy (SEM). Cobalt accumulation increased linearly with time, consistent with apparent first-order dependence on aqueous Co concentration under constant exposure, reaching 38 ± 3 mg·kg⁻¹ after 28 days at 60 µg·L⁻¹, with no saturation observed. The concentration-dependent Co accumulation was well described by an empirical power-law model (Q = KC₀ⁿ), with the empirical coefficient K increasing linearly over time, reflecting the progressive increase in Co accumulation at a given aqueous concentration. Microbial colonization developed rapidly on MPs, with 16S and 18S rRNA gene copy numbers stabilizing after 14 days, while surface-normalized Co signals increased sharply after day 21, indicating a time-dependent modification of biofilm properties influencing Co retention. SEM confirmed complex microbial structures, including diatom-like cells. No cobalt adsorption was observed under sterile conditions, confirming the key role of biofilm presence. These findings highlight the dynamic role of the plastisphere as a chemically and biologically active interface under environmentally realistic riverine conditions, with implications for contaminant fate, bioavailability, and risk assessment in freshwater systems affected by plastic pollution. Full article

Microplastics (MPs) are emerging pollutants widespread in aquatic environments; however, their effects across the different life stages of aquatic organisms remain poorly understood. This systematic review integrates recent experimental results on the developmental, physiological, and neurobehavioral effects of MP exposure on zebrafish (Danio rerio), a popular model organism for ecotoxicology research. A PRISMA-guided search using Web of Science (WoS) and Scopus as databases generated 581 articles, which were screened to 60 eligible articles. The collated results showed that MP toxicity at various life stages of zebrafish was strongly related to the physicochemical properties of MPs and exposure conditions. In terms of developmental toxicity, peer-reviewed publications assessing specific MP physicochemical properties—polymer type, size, concentration, shape, and degree of aging—reported concentration-dependent effects, with increasing MP concentrations generally associated with growth inhibition, cardiac dysfunction, increased malformations, and lower hatching rate, particularly at ≥10 mg/L to ≥100 mg/L. However, several studies noted that under particle-based exposure scenarios, MP toxicity exhibited threshold-like or non-monotonic responses, attributed to aggregation, bioavailability, and uptake dynamics. Weathered and artificially aged MPs exhibited higher embryotoxicity and neurodevelopmental toxicity, including changes in gene expression of neurons, decreased integrity of motor neurons, and impaired retinal development, compared with “virgin” MPs. In terms of physiological endpoints, oxidative imbalance like changes in the activity of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx)), lipid peroxidation, inflammation, and disruption of tight junctions have been reported as key toxicity pathways. Chronic MP exposure in zebrafish also caused changes in the gut microbiota, hepatic metabolism, endocrine disruption, reproductive damage, thyroid function disruption, and genotoxicity in zebrafish. In terms of neurobehavioral effects, changes in locomotor activity, anxiety response, neurotransmitter homeostasis, and acetylcholinesterase function, have been observed, in both larvae and adults, with a potentiation effect in aged MP exposure. Finally, this systematic review found major limitations for inter-study comparisons because of inconsistencies and differences in methodology applied related to MP concentration, simulation of natural MP aging, and MP dose measurements. Full article

Atmospheric microplastics have emerged as an important environmental contaminant due to their widespread occurrence, persistence, and potential ecological and human health implications. However, information regarding atmospheric microplastic deposition in southeastern Europe remains extremely limited. The present study provides a preliminary moss-based assessment of atmospheric microplastic deposition at selected locations in North Macedonia. Moss samples were collected from sites representing different degrees of anthropogenic influence and analyzed following sample preparation procedures consistent with previous national-scale surveys. Microplastic particles were identified using micro-Fourier Transform Infrared (μ-FTIR) spectroscopy. Microplastics were detected in all investigated moss samples, confirming their widespread atmospheric deposition across the country. The highest concentration was recorded at Vodno–Skopje (16.72 MP g⁻¹ dry weight), followed by Majdan (7.10 MP g⁻¹) and Bojančište (3.29 MP g⁻¹). Pronounced differences in polymer composition were observed among the sampling locations: Vodno–Skopje exhibited the greatest polymer diversity, with polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polylactic acid (PLA), and cellulose acetate (CA) all detected above their respective limits of detection, whereas Majdan was characterized almost exclusively by polyethylene terephthalate (PET) and Bojančište primarily by cellulose acetate (CA) and PLA. The detected microplastic concentrations were within the range of values reported in some European studies, although direct comparisons should be interpreted with caution because of the differences in sampling and analytical methodologies. The findings demonstrate the potential of moss-based biomonitoring as a complementary approach for assessing atmospheric microplastic deposition. However, studies covering a larger number of sampling locations and different temporal periods are required to further evaluate and validate this approach. Full article

Background: Airborne microplastics (AMPs) are an emerging air pollutant and there are growing concerns about their potential effects on respiratory health due to their persistence, inhalability and ability to carry other toxic pollutants. Methods: Relevant peer-reviewed studies released from 2015 to 2025 were located by searches on PubMed, Scopus, and Web of Science. Data from experimental, epidemiological, and review research were amalgamated to investigate sources of airborne microplastics, routes of exposure, analytical methodologies, respiratory toxicological processes, and regulatory viewpoints. Results: Modern studies suggest inhaled antimicrobic peptides can reach the lower respiratory tract and cause chronic pulmonary inflammation via induction of oxidative stress, mitochondrial dysfunction, epithelial barrier damage, inflammasome activation, immune system imbalance and extracellular matrix remodeling. These pathways have been associated with chronic respiratory diseases, such as chronic obstructive pulmonary disease, asthma, pulmonary fibrosis, and lung carcinoma. Toxicity can be increased by the accumulation of heavy metals, persistent organic pollutants and microbiological impurities. However, the lack of standardised protocols for exposure assessment, inconsistency of sampling and analytical methods and limited human epidemiological data hamper health risk assessment. Conclusions: Airborne microplastics are an emerging environmental health concern with potentially significant effects on respiratory health. Harmonised surveillance strategies, standardised analytical methods, improved inhalation exposure models and prolonged epidemiological studies are urgently needed to improve risk assessment and enable evidence-based air quality policy for the protection of respiratory health. Full article

Microplastic (MP) analysis in various environmental media currently faces significant challenges due to the complex and transportable nature of these materials. This study employed Fourier-transform infrared spectroscopy (FTIR) to investigate the presence of MPs in caddisfly larval cases, which incorporate vegetative fragments, sediment grains, and MP particles as building materials. The analysis of MPs in 2049 caddisfly larval cases revealed a total of 7553 items, resulting in an average of 3.7 items/case. The lowest recorded rate was 0.8 items/case, while the highest reached 18.2 items/case. Fiber MPs comprised 39.2% of the total, followed by fragment MPs at 30.8% and spherical MPs at 30%. Among the colors analyzed, blue MPs were the most prevalent, accounting for 36.6%, with white/transparent MPs at 22.1% and red MPs at 14.1%. MPs smaller than 100 µm were the most common, accounting for 37%, followed by MPs in the 100–250 µm range at 23.9%, larger than 500 µm at 22.3%, and those between 250 and 500 µm at 15.8%. Cellulose acetate was discovered to be the most abundant MP among different polymer types, followed by cellulose acetate butyrate, polyethylene terephthalate, poly(vinyl propionate), poly(ethylene glycol), poly(acrylonitrile-co-butadiene), cellulose propionate, hydroxyethyl cellulose, polyvinyl alcohol, glycerol triacetate, polystyrene, and poly(propylene glycol) methacrylate. These findings show the existence of MP in biotic components of these ecosystems, which has implications for aquatic biota health and freshwater quality, particularly in places influenced by human activity. Full article

Carboxyl-modified polystyrene microplastics (cPS-MPs) may accumulate in the liver and interfere with cellular metabolism; however, their effects may differ substantially between cancerous and non-cancerous hepatocytes. In this study, we compared the responses of HUH-7 hepatocellular carcinoma cells and immortalized human hepatocytes (IHHs) to two cPS-MP size fractions, M1 (2.1 µm) and M2 (0.49 µm), at concentrations of 10–1000 µg/mL for 24, 48 and 72 h. Cell viability was evaluated by the MTT assay, while mitochondrial morphology and membrane potential (ΔΨm) were assessed using MitoTracker fluorescence microscopy and fluorescence measurements. HUH-7 cells exhibited concentration- and time-dependent loss of viability, with the strongest cytotoxicity observed after 72 h exposure to M2 particles, when viability decreased to approximately 48% at concentrations ≥750 µg/mL. In contrast, IHH cells showed no significant cytotoxicity and exhibited metabolic stimulation under several M1 exposure conditions. Brightfield microscopy further revealed pronounced accumulation of cPS-MPs in association with HUH-7 cells, whereas IHH cells showed substantially less apparent particle accumulation. In HUH-7 cells, prolonged exposure to high cPS-MP concentrations caused extensive mitochondrial network rearrangement, loss of nuclear integrity and heterogeneous changes in ΔΨm, including pronounced hyperpolarization in individual cells and depolarization that predominated at the population level. IHH cells largely maintained mitochondrial network integrity and stable ΔΨm. Based on the experimental dataset, HepatoMP, an open-source web-based Predictive Modelling Tool, was developed as a proof-of-concept framework integrating concentration-, particle size- and time-dependent responses for interactive data visualization and extrapolation. Overall, the findings demonstrate markedly different responses of hepatoma and immortalized hepatocytes to cPS-MPs and identify particle accumulation and mitochondrial dysfunction as prominent features associated with cPS-MP cytotoxicity in HUH-7 cells. HepatoMP provides a complementary hypothesis-generating framework for guiding future experimental investigation of hepatic microplastic toxicity. Full article

Macroplastic pollution in rivers is an increasing environmental concern because rivers function simultaneously as active transport pathways and temporary storage compartments for land-based plastic waste. This study investigated the spatial distribution, composition, and size characteristics of riverbank and floating macroplastic debris in the Can Tho River, a tidal tributary of the Hau River in the Mekong Delta, Vietnam, to improve understanding of macroplastic transport, selective retention, and environmental partitioning between active transport and temporary storage compartments. Riverbank debris was surveyed at twelve sites spanning urban, peri-urban, and rural sections, while floating debris was quantified using a net-based sampling system. Riverbank accumulations exhibited pronounced local spatial heterogeneity, although litter density and mass density did not differ significantly among river sections. Plastics dominated both environmental compartments, accounting for 53–60% of accumulated debris and more than 95% of floating debris by abundance. Riverbank accumulations were dominated by plastic bags, food packaging, and beverage containers, whereas floating debris was dominated by expanded polystyrene foam products. Significant differences were also observed in material composition, plastic-product composition, and size distribution. Riverbank accumulations contained proportionally larger macroplastics (100–500 mm), whereas floating debris was dominated by smaller macroplastics (50–200 mm), supporting the role of size-dependent transport and selective retention in environmental partitioning. These findings show that floating debris and riverbank accumulations represent complementary components of the riverine plastic continuum, linking active transport and temporary storage through selective environmental partitioning. Integrating floating and riverbank monitoring provides a more comprehensive framework for understanding macroplastic transport and environmental fate while informing management strategies to reduce downstream plastic transport to the Hau River and ultimately estuarine and coastal ecosystems. Full article

Microplastics (MPs) and nanoplastics (NPs) accumulate in human hepatic and gastrointestinal (GI) tissues. However, differences in sampling strategies, tissue preparation, analytical techniques, and quality assurance procedures have resulted in substantial methodological heterogeneity, limiting the comparability and reproducibility of published findings. Therefore, this review aims to critically evaluate current analytical methodologies for the detection and characterization of MPs and NPs in hepatic and GI tissues, highlight methodological strengths, limitations, and emerging technologies, and identify priorities for methodological standardization. Studies demonstrate that no single analytical technique can simultaneously provide comprehensive information on particle size, morphology, polymer composition, spatial localization, and concentration. While Raman spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, pyrolysis gas chromatography–mass spectrometry (Py-GC/MS), and emerging multimodal imaging techniques each offer distinct advantages, reflecting their different underlying detection principles, methodological variability remains a major barrier to cross-study comparison. Human tissue studies are further constrained by limited sample availability, contamination risks, and inconsistent quality assurance procedures. Future progress will depend on harmonized, organ-specific analytical workflows integrating optimized tissue digestion, rigorous contamination control, complementary spectroscopic approaches, and standardized reporting metrics. Establishing unified methodological guidelines is essential to improve reproducibility, facilitate quantitative evidence synthesis, and advance both environmental exposure assessment and clinical research on MPs and NPs in hepatic and gastrointestinal tissues. Full article

Plastic contamination (plastamination) has become a pervasive environmental threat with growing implications for human health. Among plastic-derived contaminants, micro- and nano-plastics (MNPs) are of particular concern due to their persistence, widespread distribution, and capacity to interact with biological systems. Humans are exposed to MNPs through ingestion, inhalation, dermal contact, and maternal transfer, and these particles can cross biological barriers, including the blood–brain barrier, reaching the central nervous system. MNPs disrupt cellular homeostasis by inducing oxidative stress, mitochondrial dysfunction, and inflammation. In the brain, these processes drive glial activation and chronic neuroinflammation, which are closely associated with neuronal damage and neurological disorders, including Parkinson’s disease (PD). MNPs can also affect systemic pathways such as the gut–brain axis (GBA) and neuroendocrine regulation, suggesting broader physiological consequences. This narrative review synthesizes current evidence on the neurotoxic and pro-inflammatory potential of MNPs. Since MNPs may promote the aggregation of proteins implicated in neurodegeneration, such as alpha-synuclein, their possible role in PD is discussed. Despite several knowledge gaps, MNPs may be emerging environmental risk factors for brain health and neurodegenerative diseases such as PD. Nevertheless, there is a need for further studies in the field, standardized methodologies and longitudinal studies to implement effective mitigation strategies. Full article

Microplastics are a pervasive contaminant of aquatic, terrestrial, and atmospheric systems, with accumulating evidence of ecological harm and human exposure. Conventional workflows, manual microscopy, FTIR, and Raman spectroscopy, are labor-intensive and operator-dependent, motivating artificial intelligence (AI) and machine learning (ML) as scalable alternatives. Following PRISMA guidelines, five databases were searched; 936 records were screened and 113 primary studies met the eligibility criteria, analyzed through dual-reviewer extraction across seven dimensions. Contrary to the assumption that deep learning dominates, classical and chemometric estimators (46.0% of studies) were at least as prevalent as deep learning (36.3%), with support-vector machines the single most used family (35.4%). Method choice tracked input modality rather than recency: chemometric classifiers such as SVM and PLS dominate spectroscopic data (FTIR, Raman; 53.1% of studies), whereas deep learning concentrates in the image-based minority, where representation learning outperforms manual feature engineering. Detection/identification remained the principal task (65.5%), although 19.5% addressed predictive modeling of sorption, toxicity, distribution, and remediation. Characterization coverage was uneven: origin and polymer type were reported in 88.5% and 72.6% of studies, but size and shape in only 50.4% and 28.3%. Reported accuracies, often exceeding 90%, derive from heterogeneous, non-comparable datasets. Future progress depends on open benchmarks, standardized reporting, and explainable methods. Full article

Atmospheric microplastics are increasingly recognized as mobile particulate contaminants that can be emitted, resuspended, transported, and deposited across indoor, terrestrial, marine, high-altitude, and remote environments. However, reported abundances and particle characteristics remain difficult to compare because studies differ in sampling design, reporting units, particle-size limits, contamination control, and polymer identification. This review combines concise bibliometric mapping with a critical narrative synthesis. A Web of Science Core Collection search for 2000–2024 retrieved 356 English-language articles and reviews, of which 280 met the eligibility criteria. Publication output increased rapidly after 2020. Co-citation and keyword analyses identified three major themes: occurrence, transport, and deposition; sampling and analytical characterization; and exposure and potential ecological and health implications. The synthesis shows that active air sampling and passive deposition collection measure different atmospheric processes, while inconsistent blank correction, recovery assessment, and polymer confirmation limit inter-study comparability. Field observations and modelling support long-range transport and the importance of particle morphology, but quantitative source attribution remains uncertain. Current evidence supports inhalation exposure and biological plausibility, yet is insufficient to establish population-level risks or causal links with specific diseases. Future research should prioritize harmonized monitoring, stronger QA/QC, improved detection of small particles and nanoplastics, and integrated transport–exposure assessment. Full article

Polystyrene (PS) thermal degradation involves localized molecular bond-cleavage events that are not directly equivalent to the apparent kinetic parameters obtained from bulk thermal analysis. In this study, a finite hydrogen-terminated PS oligomeric model was examined using density functional theory at the M06-2X/LANL2DZ level, whereas the non-isothermal degradation behavior of a PS sample was independently evaluated by thermogravimetric analysis under nitrogen. The computational analysis considered frontier molecular orbital distributions and site-specific thermodynamic descriptors associated with homolytic C–C cleavage and radical-mediated β-scission reactions. The calculated HOMO–LUMO gap of 742.62 kJ mol⁻¹ indicated a comparatively large orbital-energy separation within the selected oligomeric model, while the localization of the frontier orbitals over aromatic and benzylic regions revealed a spatially heterogeneous electronic distribution. Homolytic C–C cleavage exhibited bond dissociation energies ranging from 414.09 to 481.24 kJ mol⁻¹, demonstrating that the thermodynamic requirement for radical generation depends on the local molecular environment of the evaluated structure. The Gibbs free-energy changes calculated for the selected radical β-scission reactions ranged from 55.44 to 189.41 kJ mol⁻¹. These quantities represent model-dependent reaction thermodynamics and should not be interpreted as activation barriers because transition states were not calculated. Thermogravimetric analysis showed systematic increases in Tonset and Tmax with increasing heating rate, consistent with kinetic delay and thermal-lag effects under non-isothermal conditions. The Kissinger method yielded a global apparent activation energy of 186.61 kJ mol⁻¹, whereas the residual-mass-corrected Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose methods produced average apparent activation energies of 180.81 and 178.49 kJ mol⁻¹, respectively, over α = 0.05–0.95. Across the same conversion interval, the FWO apparent activation energy increased from 143.10 to 221.71 kJ mol⁻¹, while the KAS values increased from 140.10 to 220.23 kJ mol⁻¹, indicating an evolving macroscopic degradation response with greater uncertainty toward high conversion. The computational and experimental datasets were therefore interpreted as complementary but non-equivalent scale-dependent descriptions: DFT compares the relative thermodynamics of selected molecular reactions within a finite isolated oligomer, whereas TGA characterizes the global apparent kinetic behavior of the condensed polymer sample. No direct numerical correspondence was established between the molecular reaction energies and the TGA-derived apparent activation energies, and no individual cleavage reaction was assigned to a specific conversion interval. Extrapolation of these results to high-molecular-weight, polydisperse, additive-containing, cross-linked, or environmentally aged PS microplastics should therefore be made with caution. Full article