Microplastics

Microplastic (MP) contamination in riverine systems poses a growing environmental challenge, and their spatial and temporal variability complicates proper assessments. This study investigated MP concentrations (≥10 µm) across three German rivers using fluorescent staining-based detection. The results reveal highly heterogeneous distributions ranging from 4 to 1761 MP/L. The Rehbach displayed the highest mean MP concentration (540 ± 476 MP/L), whereas the Alb had the lowest (98 ± 54 MP/L). Long-term monitoring underscored pronounced temporal fluctuations linked to changing inputs, weather events, and hydrodynamics. To capture these fluctuations, monitoring campaigns must consider an appropriate temporal sampling framework. Further, to address detection challenges, the study compared 0.5 L grab sampling with 100 L pump sampling (PSU) and observed that the PSU yielded 4.7 times higher MP concentrations with improved reproducibility (27 ± 25% vs. 49 ± 33%). These results highlight the critical need for standardized protocols and scalable, cost-effective methods for reliable MP quantification and hotspot identification in freshwater environments. Full article

The climbing perch, Anabas testudineus, is one of the most widely distributed freshwater amphibious fishes in South and Southeast Asia, inhabiting both natural and artificial water bodies polluted by plastic waste. Current mesocosm experimental study aimed to investigate behavioral responses of wild fish to floating expanded polystyrene (EPS) pellets, with a focus on the biofilm developing on their surface. For biofilm formation, the pellets (diameter 3–4 mm) were exposed for two, six, and fourteen days in an irrigation canal inhabited by climbing perch. Development of an intensive biofilm was observed on days 6 and 14 of exposure, characterized by a high diversity of organisms, including protozoa, cyanobacteria, algae, amoebae, and fungi. Fish feeding behavior was observed in the presence of feed pellets, clean EPS pellets, and three variants of EPS pellets with biofilm developed on their surfaces in the freshwater environment. The fish rapidly grasped and ingested feed pellets compared to all variants of plastic pellets. Climbing perch grasped all types of EPS pellets but always rejected them after oral cavity testing. The time to the first grasp was significantly longer for both clean EPS and EPS exposed for two days compared to feed pellets. Biofilm appeared to function as a taste deterrent for the fish: the duration of oral cavity testing was negatively correlated with the EPS pellet exposure timings in natural conditions. We suggest that floating plastic stimulates foraging behavior in the fish, and the duration of this behavior was significantly longer than that observed with feed pellets. The similarity of positive buoyant EPS pellets to natural food objects may stimulate the fish movements towards the water surface, which likely results in greater energy expenditure and increased risk of predation, without any apparent benefit to the individual. Full article

There is limited research that addresses microplastics (MPs) contamination on the surfaces of fruits and vegetables. This study quantifies and characterizes MPs on the surface of tomatoes, apples, grapes, and cucumbers purchased from three markets (A, C, L). MPs were examined by stereomicroscopy, hot needle tests, and Scanning Electron Microscopy with Energy Dispersion Detector (SEM-EDX), and the results were reported by abundance, shape, color, and composition. Grapes in market A had the highest surface MPs concentration with a maximum of 0.891 particles/mm², while tomatoes in the same market had the lowest, at 0.030 particles/mm². The majority of MPs (> 85%) were transparent. Tomato, grape, and cucumber surfaces in all markets predominantly contained fragments, while apple surfaces primarily contained fibers. SEM-EDX analysis revealed MPs were primarily composed of carbon and oxygen and provided insights into the surface structures, elemental compositions, and sizes. Exposure assessment revealed the highest estimated daily intake (EDI) occurred in grapes from market A, at 9.24 × 10⁻⁵ MPs/kg/day for adults and 4.04 × 10⁻⁴ MPs/kg/day for children. Although the values appear low, no regulatory limits exist. Surface contamination remains an overlooked exposure route, emphasizing the need for food safety policies addressing MPs contamination and their effect on human health and the environment. Full article

Human exposure to micro- and nanoplastics (MNPs) in the environment and their potential health effects are of growing public interest. Regarding water, that interest grows because multiple studies found MNPs in different matrices including tap and bottled water. We intended to (i) understand how MNPs enter freshwater systems and drinkable water, (ii) assess the evidence of human exposure to MNPs in water, and (iii) identify data gaps to support the determination of potential health effects. We searched the literature and selected studies via rigorous inclusion criteria, analyzed the data assessing the reliability of findings, and identified data gaps associated with human exposure to MNPs in water. The lack of standard sampling and analytical methods for testing MNPs in water constitutes a barrier to make accurate comparisons. The diverse analytical methods to fully characterize MNPs led to different findings in samples of similar matrices. Current drinking and wastewater treatment systems are not designed to remove MNPs. However, efforts to enhance the precision and accuracy of MNPs’ characterization and their removal by treatment systems are promising. Therefore, addressing data gaps could produce reliable data for conducting exposure and risk assessments, protect our communities, and control the mobility of MNPs to minimize exposures. Full article

Biodegradable plastics are increasingly proposed as environmentally friendly alternatives for disposable dishes or glasses in addition to their more conventional uses as foils and in bags. If produced from certified degradable materials, such items are expected to degrade rapidly during state-of-the-art composting. However, conditions prescribed for the testing and certification of materials differ from those typically applied in industrial composting, and operators of the corresponding plants have found that degradation is incomplete. In this study the degradation of commercially available biodegradable bags as well as disposable sparkling wine glasses was studied in a series of pilot-scale composting campaigns closely mimicking state-of-the-art composting conditions. The materials were characterized regarding their chemical composition, structure, and crystallinity, as well as the changes thereof throughout the process. Evidence is given that parameters such as crystallinity change significantly during composting, which may inhibit breakdown during the process and thus have unknown consequences for the subsequent environmental impact. Full article

The growth in the production and use of biodegradable plastics, positioned as an environmentally friendly alternative to traditional polymers, has led to an increase in their distribution in the environment. However, in conditions other than industrial composting facilities, biodegradable polymers can persist for a long time, fragment, and form biodegradable micro- and nanoplastics (BioMNP) with potential toxicity. Unlike traditional microplastics, the impact of BioMNP on human health has been poorly studied. This review summarises the available data on the cytotoxicity of BioMNP, including mechanisms of interaction with human cells, routes of entry into the body, induction of inflammation, oxidative stress, and cellular dysfunction. Particular attention is paid to the interaction of microplastics with cells of various body systems, including the digestive, respiratory, immune, and urogenital systems, as well as with the skin. The identified knowledge gaps highlight the need for further research to assess the risks associated with the impact of BioMNP on humans and to develop safer forms of biopolymers. Among biodegradable plastics, PLA-based particles tend to exhibit stronger cytotoxic effects. Nanoplastics generally induce more severe cellular responses than microplastics. Organs such as the liver and lungs appear particularly vulnerable. Full article

The increasing presence of microplastics (MPs) and nanoplastics (NPs) in environmental matrices presents substantial analytical challenges due to their small size and chemical diversity. This study introduces a novel enzymatic biosensor based on the Surface Plasmon Resonance (SPR) platform for the sensitive detection of MPs and NPs, utilizing laccase as the recognition element. Standard plastic particles, including polystyrene (PS, 0.1 µm), polymethyl methacrylate (PMMA, 1.0 µm and 100 µm), and polyethylene (PE, 34–50 µm), were analyzed using SPR angular interrogation along with a fixed-angle scheme. The angular approach revealed a clear relationship between the resonance angle, particle size, and refractive index, while the fixed-angle method, combined with immobilized laccase, facilitated specific detection through enzyme/substrate interactions. The analytical parameters showed detection limits ranging from 7.5 × 10⁻⁴ µg/mL (PE, 34–50 µm) to 253.2 µg/mL (PMMA, 1 µm), with significant differences based on polymer type and enzymatic affinity. Application of the biosensor to real rainwater samples collected from two regions in Mexico (Tula and Molango) confirmed its functionality, although performance varied depending on matrix composition, exhibiting inhibition in samples with high manganese (Mn²⁺), chromium (Cr²⁺), and zinc (Zn²⁺) content. Despite these limitations, the sensor achieved a 113% recovery rate in Tula rainwater, demonstrating its potential for straightforward in situ environmental monitoring. This study highlights the capabilities of laccase-based SPR biosensors in enhancing microplastic detection and underscores the necessity of considering matrix effects for real-world applications. Full article

Plastic pollution represents a persistent global issue, with catastrophic effects on ecosystems. Due to unique properties, these synthetic materials do not break down into biodegradable compounds when naturally dispersed, but degrade into smaller fragments, known as micro- (MPs) and nanoplastics (NPs), that easily enter the food chain. Among plastics, polypropylene (PP) is one of the most common, whose consumption has dramatically increased in recent years for single-use packaging and surgical masks. In this context, given the widespread detection of PP-MPs and NPs in various biological matrices, investigating their toxicity in living organisms is crucial. For these reasons, this study aims to assess how PP-MPs and NPs affect tissue regeneration following injury, proposing the freshwater leech Hirudo verbana as an established experimental model. Injured leeches were examined at different time points after plastic administration, and analyses were conducted using microscopy, immunofluorescence, and molecular biology techniques. The results demonstrate that plastic exposure induces fibrosis, disrupts tissue reorganization, delays wound repair, and activates the innate immune and oxidative stress responses. In summary, this project provides new insight into the adverse effects of PP particles on living organisms, highlighting for the first time their negative impact on proper tissue regeneration. Full article

This study presents the first investigation into the distribution of microplastics (MPs) in Sasebo City, Japan, using principal component analysis (PCA) in conjunction with water flow velocity and salinity variables. The mean MP abundance was 82.4 ± 47.7 items/m³ (SSB1–SSB4), showing no significant difference among sampling points. The fragment-to-fiber ratio was 76:24, and polypropylene and polyethylene (each 41%) were the main polymers. Fragment abundance increased with decreasing particle size, while fibers were rare below 700 μm. PCA indicated distinct MP polymer and shape distributions corresponding to stagnant water (SSB1), high-flow conditions (SSB2 and SSB3), and seawater (SSB4). Based on the literature, the study area represents a case of a small-scale aquatic system with limited anthropogenic influence due to moderate population, short river length, efficient effluent discharge, minimal industry, good water quality, and the absence of significant spatial variation in MP abundance. The infrequent precipitation during the sampling event supports the findings of the present study as a reliable baseline for objectively assessing MP contamination. Compared to aquatic systems of varying scales and anthropogenic influence, this baseline is applicable to both small-scale and large-scale aquatic systems with significant influences. This will serve as a valuable reference for future MP studies across diverse freshwater environments. Full article

Microplastics and metals are increasingly recognised as major water contaminants with profound environmental and health consequences. The environmental co-occurrence of microplastics and metals are well documented in waterways, including urban runoff, highway balancing ponds, industrial wastewater, and mine-impacted waters, posing a multifaceted environmental threat. Urgent remedial action is required to remove co-occurring microplastics and metals from water, giving consideration to how their co-occurrence can affect remediative efforts. However, information on the sorption of microplastics and Pb and Zn simultaneously by biochar is lacking. In this current study, changes in the quantity of metal adsorbed by pristine larch biochar and magnetised larch biochar due to the presence of microplastics was assessed using spectroscopic techniques. This study demonstrated that magnetised larch biochar and pristine larch biochar both remove co-occurring microplastics, Pb, and Zn from solution. Neither magnetised larch biochar nor pristine larch biochar show any statistical difference in the sorption of Pb with the inclusion of microplastics into the aqueous matrix. However, the inclusion of microplastics result in the reduced sorption of Zn by 43% for magnetised larch biochar (p < 0.01) and 69% for pristine larch biochar (p < 0.01). Magnetised larch biochar also demonstrated greater sorption than pristine larch biochar for microplastics (p < 0.05), Zn co-occurring with microplastics (p < 0.05), and Zn with no microplastics present (p < 0.01). Despite the effects of competitive sorption between Zn and microplastics, the removal of Pb, Zn, and microplastic from a multi-contaminant system indicate that magnetic larch biochar is a viable option to remove multiple contaminants from aqueous environs where metals and microplastics are seen to co-occur. Full article

Microplastic pollution in the Chesapeake Bay is of critical concern as estuaries serve as habitats and nurseries for diverse aquatic organisms and offer vital ecological services. However, quantitative analysis of microplastics, especially those smaller than 300 µm, in the natural aquatic environment is very challenging due to a lack of efficient sampling methods. This study takes a novel approach to quantify the abundance, size distribution, and morphological characteristics of microplastics, as small as 20 µm, in the surface waters of the Chesapeake Bay. Water samples (10 L) were collected monthly from July 2023 to October 2023 at four locations along the Chesapeake Bay. The samples were digested with a 10% potassium hydroxide solution and subjected to density separation using sodium chloride (ρ = 1.2 g/cc). Microplastic particles were examined using a Shimadzu AIM–9000 FTIR microscope for enumeration and chemical identification. Overall, the mean microplastic concentration observed was 766.16 ± 302.59 MP/L, significantly higher than previously estimated in the Chesapeake Bay. Microplastic abundance exhibited a significant (p = 0.02) spatial variation across the four sampling locations. Most abundant were particles less than 100 µm (60.65%), followed by particles between 100 µm and 300 µm (23.19%), and particles exceeding 300 µm (16.16%). Morphological analysis identified fragments as the dominant shape (86.02%), followed by fibers (11.87%), and beads (2.10%). This study underscores the importance of standard and efficient sampling methods in microplastics research. By sampling microplastics as small as 20 µm, this research demonstrated that the abundance of microplastics in the Chesapeake Bay is significantly higher than previously estimated and dominated by smaller–sized particles. These small microplastics are more likely to enter the food web where human exposure may occur. Therefore, microplastic pollution in the Chesapeake Bay ecosystem has the potential to impose environmental and public health risks. Full article

Microplastics, synthetic polymer particles measuring less than 5 mm, have become a widespread environmental pollutant, raising concerns over their possible effects on human health. Growing evidence links MPs to vascular aging and cardiovascular disease beyond their ecological toxicity. Upon inhalation, ingestion, or skin contact, microplastics can traverse biological barriers, circulate systemically, and accumulate in vascular tissues. Experimental investigations indicate that MPs, especially polystyrene and polyethylene in nano- and micro-sized forms, induce oxidative stress, mitochondrial dysfunction, and chronic inflammation. These disruptions activate redox-sensitive signaling pathways, such as NF-κB and NLRP3 inflammasome, causing endothelial dysfunction, vascular smooth muscle modulation, and foam cell production, indicating early vascular aging. Animal models and in vitro studies have consistently shown endothelial activation, increased cytokine production, and changes in vascular tone after exposure to MPs. Initial human research has detected microplastics in blood, thrombi, and atherosclerotic plaques, which correlate with negative cardiovascular outcomes and systemic inflammation. Notably, recent research suggests that the gut microbiota and antioxidant systems may play a role in adaptive reactions, although these processes are still not fully understood. MP-induced vascular toxicity is covered in this interdisciplinary review, highlighting molecular pathways, experimental data, and translational gaps. Full article

Accurate identification of microplastic polymers in marine environments is essential for tracing pollution sources, understanding ecological impacts, and guiding mitigation strategies. This study presents a comprehensive, explainable-AI framework that uses Raman spectroscopy to classify pristine and weathered microplastics versus biological materials. Using a curated spectral library of 78 polymer specimens—including pristine, weathered, and biological materials—we benchmark seven supervised machine learning models (Decision Trees, Random Forest, k-Nearest Neighbours, Neural Networks, LightGBM, XGBoost and Support Vector Machines) without and with Principal Component Analysis for binary classification. Although k-Nearest Neighbours and Support Vector Machines achieved the highest single metric accuracy (82.5%), k NN also recorded the highest recall both with and without PCA, thereby offering the most balanced overall performance. To enhance interpretability, we employed SHapley Additive exPlanations, which revealed chemically meaningful spectral regions (notably near 700 cm⁻¹ and 1080 cm⁻¹) as critical to model predictions. Notably, models trained without Principal Component Analysis provided clearer feature attributions, suggesting improved interpretability in raw spectral space. This pipeline surpasses traditional spectral matching techniques and also delivers transparent insights into classification logic. Our findings can support scalable, real-time deployment of AI-based tools for oceanic microplastic monitoring and environmental policy development. Full article

Plastic pollution in marine environments poses a new global threat. Microplastics (MPs) can bioaccumulate in marine organisms, leading to oxidative stress (OS). This study investigates MP accumulation and associated OS responses in six invertebrate species (Bivalvia, Gastropoda, and Malacostraca) and three key fish species of the Bulgarian Black Sea ecosystems. The target hydrobionts were collected from nine representative coastal habitats of the northern and southern aquatory. MPs were quantified microscopically, and OS biomarkers (lipid peroxidation, glutathione, and antioxidant enzymes) were analyzed spectrometrically in fish liver and gills and invertebrate soft tissues (STs). The specific OS (SOS) index was calculated as a composite indicator of the ecological impact, incl. MP effects. The results revealed species-specific MP bioaccumulation, with the highest concentrations in Palaemon adspersus, Rathke (1837) (0.99 ± 1.09 particles/g ST) and the least abundance in Bittium reticulatum (da Costa, 1778) (0.0033 ± 0.0025 particles/g ST). In Sprattus sprattus (Linnaeus, 1758), the highest accumulation of MPs was present (2.01 ± 2.56 particles/g muscle). The correlation analyses demonstrated a significant association between MP counts and catalase activity in all examined species. The SOS index varied among species, reflecting different stress responses, and this indicated that OS levels were linked to ecological conditions of the habitat and the species-specific antioxidant defense potential to overcome multiple stressors. These findings confirmed the importance of environmental conditions, including MP pollution and the evolutionarily developed capacity of marine organisms to tolerate and adapt to environmental stress. This study emphasizes the need for novel approaches in monitoring MPs and OS to better assess potential ecological risks. Full article

Microplastics are an increasing concern due to their widespread occurrence in aquatic environments worldwide. The lack of a harmonised protocol for their reliable quantification remains a major challenge in current scientific efforts. This study presents a comparative evaluation of three protocols for the detection and quantification of microplastics in aqueous samples. The protocols were assessed based on quantification efficiency, risk of particle degradation, staining performance, operational complexity, and cost per sample. Protocol A combined Rhodamine B and ethanol staining with NaCl-based density separation, demonstrating strong isolation performance while maintaining minimal chemical hazards and moderate cost (2.45€ per sample) that could be further reduced to 0.45€ per sample by substituting reagent-grade NaCl with table salt. Protocol B offered moderate isolation capacity and presented the highest risk of particle fragmentation, likely due to the use of acetone and high-temperature digestion. Protocol C, based on the combined use of Nile Red and ZnCl₂, also presented a risk of particle fragmentation, resulting in the highest MP count for small and hydrophobic particles. In addition, its high cost (15.23€ per sample) limits its suitability for routine application. Full article

Nanoplastics (NPs), the tiniest and one of the most problematic fractions of plastic pollution, present dangers because of their size, reactivity, and ecosystem interactions. This review highlights the distinct characteristics, sources, routes, and ecological effects of NPs, a substantial subgroup of plastic pollution. With a focus on their ecological and toxicological implications, this review highlights the unique qualities of NPs and their functions in wastewater and urban runoff systems. The analysis of NPs’ entry points into terrestrial, aquatic, and atmospheric ecosystems reveals difficulties with detection and quantification that make monitoring more difficult. Filtration technologies, adsorption-based techniques, and membrane bioreactors are examples of advanced technical solutions emphasized as efficient NP mitigation measures that can integrated into current infrastructure. Environmental effects are examined, including toxicological hazards to organisms in freshwater, terrestrial, and marine environments, bioaccumulation, and biomagnification. This analysis emphasizes the serious ecological problems that NPs present and the necessity of using civil and environmental engineering techniques to improve detection techniques, enact stronger laws, and encourage public participation. Full article

Microplastics are pervasive environmental pollutants that pose risks to human health through ingestion and inhalation. This review synthesizes current practices to reduce exposure and toxicity by examining major exposure routes and dietary interventions. More than 130 papers were analyzed to achieve this aim. The findings show that microplastics contaminate a wide range of food products, with particular concern over seafood, drinking water, plastic-packaged foods, paper cups, and tea filter bags. Inhalation exposure is mainly linked to indoor air quality and smoking, while dermal contact poses minimal risk, though the release of additives from plastics onto the skin remains an area of concern. Recommended strategies to reduce dietary exposure include consuming only muscle parts of seafood, moderating intake of high-risk items like anchovies and mollusks, limiting canned seafood liquids, and purging mussels in clean water before consumption. Avoiding plastic containers, especially for hot food or microwaving, using wooden cutting boards, paper tea bags, and opting for tap or filtered water over bottled water are also advised. To mitigate inhalation exposure, the use of air filters with HyperHEPA systems, improved ventilation, regular vacuuming, and the reduction of smoking are recommended. While antioxidant supplementation shows potential in reducing microplastic toxicity, further research is needed to confirm its effectiveness. This review provides practical, evidence-based recommendations for minimizing daily microplastic exposure. Full article

Microplastics (MPs) are a major contaminant in aquatic environments. Due to their size, they are likely to cause deleterious effects. In this study, we assessed the effects of MPs obtained from two commercially available plastics (PP and PET) in the polychaeta Hediste diversicolor after different periods (4 and 28 days). Toxic effects were assessed by measuring burrowing and spontaneous activities, phase I (CYP1A1, 1A2, and 3A4) activities), conjugation metabolism (GSTs), and antioxidant defense (CAT). Behavioral traits and phase I activities were nonresponsive to the presence of both plastics and for the two durations of exposure, indicating that these organisms are not affected by exposure to MPs and do not metabolize them. Conjugation metabolism was inhibited, which may be explained by the MPs’ capability of inhibiting certain enzymes. CAT activity was increased in animals acutely exposed to PP and decreased in animals chronically exposed to PET. This study shows that PP- and PET-MPs do not cause adverse effects on H. diversicolor. Full article

Nano- (NPs) and microplastics (MPs) are ubiquitous and raising concerns about their toxicity. A popular model for studying acute toxicity is Danio rerio. This study investigated the acute toxicity in FET test of polystyrene nanoparticles (500 nm, nanoPS) at different concentrations (0.01, 0.1, and 0.2 mg/mL), with different surface groups (non-modified, amine, carboxyl) and discuss the toxicological contribution of commercially added compounds. Different behavioural tests were used to investigate the neurotoxicity of nanoPS and sodium azide: coiling assay test, light–dark preference test, and colour preference test. Sodium azide and other preservatives are often present in commercially available NP and MP solutions frequently used in microplastic toxicity tests, but their effects on the results remain largely unknown. In the FET test, nanoPS did not increase mortality or affect the heart rate or body length. A higher hatching rate was observed at 48 hpf. Although nanoPS showed no acute toxicity, behavioural tests revealed subtle neurotoxic effects (changes in colour preference), suggesting a potential impact on neurological function. Additionally, sodium azide exhibited toxicity, indicating that additives may confound toxicity assessments. This highlights the need for careful consideration of preservatives in nanoparticle research to avoid misleading conclusions. Full article