Microplastics

Detection and quantification of microplastics are undermined by the absence of appropriate methods in some contexts—such as a statistically principled LOD for particle-count data—but more pervasively by the uncritical application of ostensibly simple rules outside the conditions under which they are valid. This paper examines the statistical and study-design decision points where such failures most commonly occur and articulates principled constraints on valid inference at each step. Specifically, it (1) distinguishes exploratory from confirmatory research and advocates preregistration to prevent HARKing; (2) argues for field-blank-based limits to improve internal validity; (3) shows how multiple simultaneous comparisons against the LOD inflate the family-wise error rate and how to adjust α accordingly; (4) demonstrates that the LOD multiplier kD depends on blank sample size and critiques fixed-multiplier heuristics lacking statistical justification; (5) examines the consequences of distributional misspecification for LOD estimation; (6) demonstrates that an LOD for summed polymer concentrations exists only under restrictive conditions; (7) clarifies why subtracting limits from individual measurements is not quantification, and that cohort-level inference requires a median comparison via log-transformed data with a corresponding confidence interval; and (8) introduces a Bayesian framework for particle-count LODs that accounts for partial filter inspection. These discussions are summarized in a minimum reporting checklist designed as an evaluative aid—not a prescriptive recipe—to help researchers make analytical choices explicit and support reviewers in assessing methodological validity. Full article

Soils are increasingly affected by microplastic (MP) contamination, mainly coming from industrial activities, agricultural practices, atmospheric or waterborne transport, and improper waste disposal. Despite the increasing attention to the fate of MPs in soil over the last few years, research in this area is still limited compared to aquatic ecosystems. The introduction of MPs into the soil environment can modify not only the soil properties but also the interactions among soil components, plants, and microorganisms, thus affecting the mobility and availability of other contaminants, such as potentially toxic elements (PTEs). This review critically examines the complex dynamics between MPs and PTEs in the soil ecosystem, with a focus on the conditions under which MPs can act as a source or a sink of PTEs. Indeed, on the one hand, MPs can adsorb or complex PTEs on their surfaces (similarly to natural soil colloids), thus reducing their mobility and availability; on the other hand, they can release/mobilize PTEs after MP degradation or act as micro-/nano-vectors of PTEs. Understanding such mechanisms is relevant when evaluating the environmental risks associated with the co-presence of MPs and PTEs in soil, a situation likely to occur in most contaminated sites and in many agricultural soils. Full article

Plastics are now ubiquitous in the environment, in this, the “Plasticene” era. Microplastics (MPs) and Nanoplastics (NPs) are emerging contaminants of global concern. This systematic review, registered on PROSPERO and conducted according to PRISMA guidelines, investigated the presence, distribution, and characteristics of MPs in tap water (TW) worldwide, and estimated the population’s Estimated Daily Intake (EDI) by age group, including pregnant women. A comprehensive search across PubMed, Scopus, Web of Science, and Cochrane identified 22,650 records, of which 8 studies were included. MPs were detected in treated water (TW) in the studies included in this review, although the currently available evidence remains limited. Calculated EDIs were highest in children aged 6 months to 3 years (up to 39 MPs/kg bw/day), followed by pregnant women (up to 14.96 MPs/kg bw/day), reflecting differences in water intake per body weight. These estimates must be interpreted as indicative, estimated by methodological variability among studies. The widespread presence of MPs in TW calls for standardized methods, improved treatments, and thorough monitoring to assess risks and protect public health. Full article

There are currently no published methods for the controlled introduction of microplastic particles into the European rabbit (Oryctolagus cuniculus) as an animal model. The aim of this pilot study was to establish a novel rabbit-based experimental model for assessing the impact of microplastic particles by evaluating the physiological and biochemical responses to an eight-day oral administration of polystyrene latex (1 and 5 mg/kg/b.w./day), providing a foundation for future studies. This study was also aimed at evaluating the possibility of using Raman spectroscopy and Fourier-transform infrared spectroscopy to analyze the distribution of microplastics in rabbit samples. We observed a dose-dependent decrease in water and food consumption in the high-dose (5 mg/kg) study group. In addition, a decrease in alanine aminotransferase and total calcium levels, along with an increase in phosphorus levels, was detected. The rabbit’s stomach was the only organ where polystyrene microparticles were identified, with the colon, kidneys, ovaries, and uterus not showing any evidence of polystyrene presence. The selected doses of microplastics did not lead to pronounced toxic effects in rabbits and may be used on larger animal samples. Physiological and biochemical data obtained indicate predominantly negative metabolic shifts associated with the intake of microplastics, which warrants further study. Full article

Micro- and nanoplastic (MNP) pollution has emerged as a global environmental and health concern, driving the rapid development of sensor technologies for faster, more sensitive, and field-deployable detection. This review synthesizes recent advances in optical, electrochemical, and biosensor platforms for MNP analysis and compares their analytical performance and practical feasibility. Optical sensors, including plasmonic, spectroscopic, and colorimetric systems, enable label-free and often rapid detection with material discrimination capability, and are well-suited for screening applications, though they commonly exhibit higher detection limits and matrix interference. Electrochemical sensors demonstrate the highest analytical sensitivity overall, frequently reaching low µg L⁻¹ to ng mL⁻¹ levels, with strong potential for miniaturization and on-site deployment; performance is further enhanced by nanostructured electrodes, photoelectrochemical designs, and signal amplification strategies. Biosensors incorporating peptides, aptamers, enzymes, or engineered proteins provide improved polymer selectivity and enable targeted detection, but face challenges related to stability, cross-reactivity, and reproducibility in complex samples. Practically, portable electrochemical and simple optical colorimetric platforms are currently the most feasible for field use, while hybrid bio-electrochemical systems show the highest performance potential. Future research should prioritize robust selective recognition elements, antifouling interfaces, standardized validation protocols, mixed-polymer quantification models, and integration with machine learning to enable reliable, real-world MNP monitoring. Full article

Soil micro- and nanoplastic contamination is escalating globally, yet its potential to interfere with routine agrochemical analyses remains poorly quantified. Standard operating procedures (SOPs) were calibrated for natural soil matrices and may not account for synthetic, carbon-rich polymers. This controlled model study quantified the analytical sensitivity of FAO/GLOSOLAN/ISO standard procedures to polystyrene nanoparticle (50 nm) contamination across a 0–0.5% (w/w) gradient in a Luvic Chernozem. Key parameters—pH, soil carbon, total nitrogen (TN), cation exchange capacity (CEC), and clay fraction—were measured following standardized protocols. The Walkley–Black method exhibited a strong dose-dependent increase in measured SOC (r = 0.93), reflecting systematic overestimation due to dichromate co-oxidation of polymer matrix, likely facilitated by exothermic heating above polystyrene’s glass transition temperature. The Dumas method showed moderate correlation (r = 0.59) but higher replicate variability driven by small aliquot size and heterogeneous nanoparticle distribution. The pH measurements displayed non-linear responses and elevated variability at low doses, whereas TN, CEC, and clay content remained statistically stable. These findings demonstrate that nanoplastic contamination can introduce significant analytical artifacts in oxidation-based SOC determinations, potentially leading to misinterpretation of soil carbon trends. Given the single-soil, single-polymer design, results represent a system-specific proof of analytical vulnerability rather than a universally quantified bias. Laboratories analyzing potentially contaminated soils should exercise caution with wet-oxidation SOC data, and broader SOP revisions must await multi-soil, multi-polymer validation campaigns. Full article

Many filter-feeding invertebrates consume microplastics (MP) under laboratory conditions, but little is known about newly settled, field-collected juveniles. To address this information gap, we collected 3439 juvenile invertebrates in the Indian River Lagoon (IRL), FL, USA. Previous studies suggest that the IRL is a MP hotspot. A total of 70% of IRL adult oysters (Crassostrea virginica) contained MP (mean: 2.3 MP/individual), and MP number and MP length were positively correlated with animal size. We predicted that juvenile C. virginica and other sessile invertebrates would contain MP with a positive correlation to animal size. Five species were examined; 51% were C. virginica (mean shell length ± SD: 6.3 ± 4.7 mm). Overall, 117 (3.4%) animals contained potential MP (fibers: 90.7%). Of these particles that matched FTIR databases with a score of 70% or greater, 51% were plastic and 49% were anthropogenically modified particles. No correlations to animal size were found for particle presence (logistic regressions: p ≥ 0.20 for all species) or particle length (linear regressions: p ≥ 0.23 for all species). Thus, even though found in a MP hotspot, our extrapolated results suggest few juveniles (<1%) contained MP. This information is important for understanding the relationship between MP and the life histories of filter-feeding animals, especially for species considered biological indicators of MP. Full article

Microplastic pollution is a major environmental concern due to its persistence, global distribution, and potential impacts on ecosystems and human health. This systematic review, conducted according to PRISMA 2020 guidelines, analyzes research trends in microplastics with a focus on physicochemical characterization and removal technologies. A literature search was performed in Scopus and Web of Science (1972–2025) using predefined inclusion and exclusion criteria. After screening and duplicate removal, 89 studies were included in the final analysis. It is considered that with this dataset, it is possible to capture the main analytical and technological developments in the field. As a bibliometric-oriented study, no formal risk-of-bias assessment was conducted. However, a qualitative consideration of potential biases was undertaken, particularly regarding publication bias, database coverage limitations, and the predominance of English-language peer-reviewed studies. These aspects were considered when interpreting the results. The Methodi Ordinatio approach was then used to rank publications based on scientific relevance and citation impact. Results show the predominance of FTIR and Raman spectroscopy for microplastic characterization, while removal technologies remain heterogeneous and less standardized, with most approaches still at laboratory scale. Key gaps include the lack of standardized analytical protocols and limited integration between detection and remediation strategies. Overall, this review highlights critical research trends and supports the development of scalable solutions for microplastic pollution. Full article

Introduction: Microplastic (MP) contamination can endanger marine ecosystems and indirectly affect the well-being of humans through the ingestion of marine species. While most research investigates the digestive system, such as the gills and gastrointestinal tract of fish, it still fails to address a major oversight in understanding MP deposition in edible tissues, which is the primary route of human exposure. The differences in contamination levels among pelagic, demersal, and benthic fish in Malaysian waters remain poorly understood. This preliminary study uses Laser Direct Infrared Imaging (LDIR), a new, high-resolution, automated technique, to examine synthetic MP contamination in the edible portion of fish. Materials and Methods: The MPs were extracted from the edible tissue of three fish species representing pelagic (Fish A), benthic (Fish B), and demersal (Fish C) using KOH and sieved onto a gold mesh filter before analysis using LDIR. Results and Discussion: LDIR identified 162 MP particles, revealing clear differences by polymer type and habitat. Pelagic species mostly contained polyethylene (PE) and rubber (n = 8). Demersal species had mostly polyethylene terephthalate (PET) with small amounts of PE and rubber (n = 57). Benthic species showed the highest load, dominated by PET and polypropylene (PP) (n = 97). The morphological assessment of the MPs indicated that the polymers in pelagic fish were smaller, with an area of 2047.82 µm² and a circularity range of 0.14–0.74, indicating consistent shape. Conversely, MPs are irregular and larger in benthic fish, with areas up to 38,837.50 µm² and circularities ranging from 0.02 to 0.81. This pattern reflects specific accumulation related to habitat and potential environmental degradation processes. Conclusions: This preliminary study demonstrates the effectiveness of LDIR for detecting MPs in edible fish tissues. The findings provide a fundamental dataset on MP contamination in edible tissue and emphasize its distribution across ecological zones. Nevertheless, broader research is required to substantiate these data and assess the implications of MP contamination for the environmental stability of human and marine well-being. Full article

Microplastics (MPs) in water treatment plants (WTPs) represent a critical environmental concern, particularly when treated effluent is reused for agricultural irrigation. This study investigates the occurrence, removal efficiency, and characterization of MPs in tertiary-treated wastewater destined for agricultural reuse in water-scarce regions. Additionally, the study examines the influence of sample volume on extrapolated MP concentrations. Despite advanced treatment processes including ultrafiltration achieving removal efficiencies of 89%, substantial quantities of MPs remain in final effluents at concentrations ranging from 89 to 399 MPs/m³ (equivalent to 0.1–0.4 MPs/L) with a mass load of 2 µg/L at the outlet. Morphological analysis revealed a shift from fragment-dominated influent (~50%) to film-dominated effluent (~51%), with blue particles being most prevalent. Size distribution analysis showed distinct peaks: 50–100 µm for fragments, 100–250 µm for films, and 250–500 µm for fibres. Polytetrafluoroethylene (PTFE) emerged as the dominant polymer across all morphotypes. Finally, converting particle counts to mass loads indicated an average decrease from ~11 µg/L at the inlet to ~2 µg/L at the outlet, underscoring that number- and mass-based metrics provide complementary information for risk assessment. Full article

With the global increase in microplastic pollution, even environments considered pristine have shown signs of being affected by these contaminants. In this context, it becomes essential to conduct studies that identify and quantify the presence of microplastics in remote regions such as Antarctica. This continent is particularly relevant due to its low anthropogenic influence and its essential role in regulating planetary ecosystems and biodiversity. In this study, 49 Antarctic samples were analyzed using pretreatment techniques with NaCl and ZnCl₂ saline solutions, followed by fluorescence microscopy using Nile Red dye to estimate the microplastic abundance index. Both solutions showed good performance in the separation and identification of particles. Approximately 37% of the samples showed contamination by potential microplastics (PMPs), with a higher concentration of particles retained on paper filters and fibers observed in the supernatants. The results indicate that the presence of MPs in Antarctica is irregular and not ubiquitous, differing from other studies that suggest a wider distribution. It is speculated that the observed contamination results from oceanic transport from other regions of the planet and from sources associated with human activities on the Antarctic continent (e.g., tourism and research). Full article

Rising plastic production worldwide is contributing to the increasing amounts of micro- and nanoplastics found in the environment. The consumption of microplastics by humans is plausible due to the presence of plastic particles in various food commodities, yet the potential impact of microplastics on human health remains unknown. Several studies have detected microplastics in human tissues and research using mammalian in vivo and in vitro models have noted toxicity after exposure to microplastics. Using both mono- and co-culture liver cell models, we assessed the impact of environmentally relevant, cryo-milled plastic particles on hepatotoxicity. We observed that only cryo-milled polyethylene terephthalate and polystyrene altered mitochondrial energy metabolism, while the other plastic particles did not. The pristine, spherical polystyrene particles were taken up at all sizes and cryo-milled polystyrene was taken up by cells. Evidently, polymer type and shape play a critical role in hepatotoxicity. Further research is required to fully elucidate the effect the physiochemical properties of plastic particles may have on toxicity. Full article

Blended polyester (PET)-based textiles comprise a significant portion of post-consumer waste, posing substantial challenges to circular economy initiatives while contributing to microfiber (MF) pollution. Despite the considerable recycling potential of PET textiles, no commercially viable technologies currently exist that can efficiently separate and recycle blended PET-based textile waste on an industrial scale. This review provides a comprehensive analysis of recycling strategies for post-consumer blended PET-based textiles and their subsequent valorization pathways. Mechanical, chemical, and biological recycling processes are mostly not yet market-ready, although chemical approaches are considered particularly promising. The findings highlight a critical need for advanced sorting technologies, enhanced material traceability, and robust MF mitigation strategies to foster circularity and contribute to the United Nations Sustainable Development Goals (SDGs). The results further indicate that mechanical recycling of blended PET textiles leads to significant MF release due to fiber fragmentation, whereas chemical recycling offers the potential for improved material recovery, but remains limited by high energy demand and solvent-related challenges. While closed-loop approaches support true circularity by maintaining textile-to-textile material flows, open-loop pathways repurpose textile waste for high-value non-textile applications. Full article

Plastic waste is estimated to represent 40–80% of the total amount of marine litter, with polyethylene (PE) and polypropylene (PP) being the most abundant polymeric components. The recovery and recycling of marine plastic debris are therefore essential to mitigate environmental pollution and limit the generation of secondary microplastics. In this work, a mechanical recycling strategy was investigated for the valorization of a polyethylene-rich plastic fraction (PE-rf) recovered from the marine environment, characterized by high heterogeneity and persistent inorganic contamination. Different pre-treatment routes, including cryogenic grinding and planetary ball milling, as well as blending approaches with recycled polyethylene and compatibilizing additives, were explored. The effects of composition and processing on the thermal, mechanical, and morphological properties of the resulting materials were systematically analyzed. The results show that intense mechanical homogenization and chemical compatibilization are not sufficient to overcome the intrinsic limitations imposed by contamination and compositional variability. As a proof of concept, selected formulations were processed into filaments and tested in fused filament fabrication, demonstrating basic 3D printability. Full article

Microplastics (MPs), i.e., plastic particles <5 mm, and nanoplastics (NPs), i.e., plastic particles <1 µm, are widespread in the environment. MPs and NPs (MNPs) have also been detected in human tissues. Environmental MNPs exhibit diverse physicochemical properties such as size, shape, and surface degradation. However, most experimental studies have used pristine MNPs, which poorly represent real-world conditions, and only a limited number of studies have focused on preparing environmentally relevant MNPs. Therefore, we focused on the key physicochemical properties of MNPs, particularly their shape, size, and surface degradation, using polyvinyl chloride (PVC) as the model polymer. In this study, fragment and spherical PVC-MNPs were utilized, and surface degradation was introduced through exposure to vacuum ultraviolet (VUV) radiation at a wavelength of 172 nm. Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) analysis revealed the formation of additional carbonyl groups after VUV exposure. We investigated the cytotoxic effects of the degraded and non-degraded PVC-MNPs on A549, Caco-2, and THP-1 cells. The results indicated that the degraded PVC-MNP-treated groups induced higher cytotoxic effects than those in the non-degraded groups. Notably, the degraded PVC-NPs induced stronger cytotoxicity than the degraded PVC-MPs. These findings highlight the potential health risks associated with environmental MNPs. Full article

This study investigates the sorption process of selected pollutants, namely naphthalene (NAP), pentachlorophenol (PCP), sulfamethoxazole (SMX), and ibuprofen (IBU), onto different real microplastics (MPs) under controlled laboratory conditions. Sorption tests reveal variable affinities depending on the chemical and physical interactions between polymers and pollutants. NAP showed the greatest uptake on the majority of tested MPs, followed by PCP and SMX, while IBU exhibited negligible sorption. Kinetic tests indicate a general rapid initial uptake, followed by lower sorption rates leading to equilibrium within days. Theoretical thermodynamic affinity estimations, based on the Hansen solubility parameter (HSP) method, previously tested only on antibiotics, are applied for the first time to commercial MPs and several pollutant categories such as PAHs, pesticides and other pharmaceuticals. Predictions have been validated with experimental results and generally show very good agreement with the affinity ranking derived by experimental data. However, some limitations occur due to the heterogeneity of the real MPs and different environmental conditions. Factors affecting, to different extents, MPs’ uptake include hydrophobicity and electrostatic forces, as well as pH and particle size. This work advances understanding of MPs’ role as vectors of pollutants in aquatic environments and validates the use of an innovative combined experimental–theoretical approach useful as a tool to predict associated risk. Full article

Microplastic (MP) contamination is increasingly recognized as a global environmental problem affecting aquatic ecosystems, food quality, and animal and human health. Farmed fish represent an important and increasing component of the human diet. Therefore, understanding potential human exposure to MPs is essential for ensuring food safety. In the current paper, we present the results of a preliminary study conducted in Bulgaria on MP contamination in the muscle tissue of rainbow trout [Oncorhynchus mykiss (Walbaum, 1792)] reared in freshwater aquaculture systems. Edible tissues were analyzed using Laser Direct Infrared (LDIR) imaging spectroscopy, a highly sensitive method enabling rapid detection and accurate identification of polymer types present in samples. MPs were detected in all examined specimens, demonstrating that these particles are bioavailable and capable of accumulating in fish muscle tissues commonly consumed by humans. Moreover, the presence of multiple polymer types suggests diverse contamination sources within aquaculture environments. Although the present findings do not allow direct conclusions about human health risks, they indicate potential risks of trophic transfer and highlight the need for improved monitoring strategies and management practices in farmed fish production. Overall, this study provides novel data on MP exposure in aquaculture species and emphasizes the preventive importance of assessing plastic pollution in fish intended for human consumption. Full article

Introduction: It is accepted that nano- and micro-plastic (NMP) pollutants threaten ecosystems and human health by their bioaccumulation but, interestingly, their toxicity is shape-dependent. However, a clear definition of irregular NMPs, as the dominant shape in environmental and biological samples, is currently lacking when compared to spherical and fibrous NMPs. Objectives: This study quantifies morphometric descriptors in order to develop a standardized definition for irregular NMPs. Methods: Hyperspectral images of 34 spherical, 50 fibrous, and 45 irregular NMPs were collected from the literature. All shape-related features reported previously were analyzed using a machine learning model. Using five-fold cross-validation, a decision tree-based ensemble classifier with fixed parameters and Gini coefficient was established to screen key morphometric descriptors and their optimal interval ranges. The model was independently validated, enabling the accurate distinction of irregular NMPs from spherical and fibrous NMPs. Results: Three morphometric descriptors, including circularity, roundness, and perimeter-to-area ratio, were identified using five-fold cross-validation as optimal indicators for NMP shape classification. Optimal interval ranges for irregular NMPs were as follows: circularity (0.388 ± 0.004–0.768 ± 0.004), roundness (0.248 ± 0.01–0.752 ± 0.06) and perimeter-to-area ratio (>11.608 ± 1.39). This approach generated a 96.0% macro-averaged accuracy across these NMPs, with 100% precision and 89.0% recall. Conclusions: Irregular NMPs may be characterized using three morphometric descriptors, such as circularity, roundness, and perimeter-to-area ratio. The three-descriptor combination has highly accurate discrimination from spherical and fibrous NMPs. Full article

Microplastic (MP) and nanoplastic (NP) pollution has emerged as a pervasive and still insufficiently quantified pressure on terrestrial ecosystems, yet its consequences for wild herbivores remain incompletely understood. As key links between primary producers and higher trophic levels, wild herbivores occupy a critical ecological position and may serve both as exposed receptors and as biological vectors of plastic contamination. This manuscript presents a narrative review that synthesizes recent advances in understanding the physiological, behavioural, and ecological implications of MP and/or NP exposure in free-ranging herbivorous mammals, integrating evidence from field surveys, experimental studies, ecological modelling, and supportive mechanistic findings from livestock and experimental mammalian systems. Available evidence indicates that MPs and NPs are consistently detected in wild herbivores from both human-modified and protected landscapes, demonstrating widespread terrestrial exposure. Reported biological effects include oxidative stress, digestive dysfunction, inflammatory and immune responses, altered gut microbial communities, impaired nutrient assimilation, and organ-level damage, although much of the mechanistic evidence derives from controlled laboratory or livestock-based studies rather than direct wildlife investigations. Behavioural responses remain comparatively underexplored, particularly in large-bodied herbivores, with limited evidence for altered foraging, habitat use, and stress-related behaviours. At the ecosystem level, emerging studies suggest that herbivores may contribute to the landscape-scale redistribution of MPs and NPs through movement and faecal deposition, with potential downstream effects on soil processes, nutrient cycling, and plant–herbivore interactions. However, the current evidence base is constrained by major methodological and conceptual limitations, including the lack of standardized detection and reporting protocols, limited ecological realism in exposure studies, taxonomic and geographic biases, and poor resolution of long-term population-level and food-web consequences. Overall, the available literature indicates that MP and NP pollution represent a multifaceted and emerging risk to wild herbivores and the ecosystems they inhabit. Future research should prioritize standardized contamination-controlled monitoring, non-invasive faecal surveillance, ecologically realistic chronic exposure studies, and integrated conservation frameworks that recognize wild herbivores as sentinel species for terrestrial plastic pollution. Full article