Microplastics

Detecting microplastics (MPs) in marine organisms is vital for understanding the ecological impact of MP pollution. Free-living marine nematodes, key players in benthic ecosystems, are often employed as bioindicators because of their sensitivity to environmental changes and thus hold promise as bioindicators for MP pollution too. This study investigated the detection of MPs in nematodes using µ-Raman spectroscopy combined with a tailored digestion protocol, targeting MPs in size ranges between 1 and 15 µm. While this is the first documented attempt to detect MPs in field-collected nematodes, significant challenges were identified. Contamination, particularly from airborne MPs and plastic-based laboratory materials, posed a major obstacle. We found higher numbers of <5 µm particles of polypropylene (PP), polyethylene terephthalate (PET), polylactic acid (PLA), polymethyl methacrylate (PMMA), and polystyrene (PS) in a natural community of nematodes compared to blank controls, suggesting the potential ingestion of small-sized MPs by nematodes in the real world. However, small MPs exhibited greater contamination challenges, underscoring the need for improved contamination control measures, such as open-air filters and plastic-free workflows. Despite these challenges, this study highlights the potential of µ-Raman spectroscopy as a valuable tool for detecting small-sized MPs in field-collected marine invertebrates, provided contamination risks are minimized. The likelihood of nematodes encountering MPs in marine sediments is high, but whether this translates to significant ingestion remains uncertain pending on the analysis of more field samples and the application of efficient measures of contamination reduction. Full article

Microplastics have emerged as a global environmental concern due to their widespread presence and potential effects on ecosystems. Wastewater treatment plants (WWTPs) play a critical role in mitigating the release of microplastics into the environment. This study aimed to evaluate the abundance and distribution of microplastics in three municipal WWTPs exhibiting different sludge and water treatment technologies. Samples were collected at various stages of the treatment process, including influent, primary and biological sludge, treated water, thickened sludge and dehydrated sludge. Quantification analyses were performed and then coupled with operational data to assess pollution flow rates and the microplastic balance. An important removal rate (>97%) of microplastics along the water line was observed in all three WWTPs. The lower performance of 0.75 mm screening was observed regarding microplastic capture compared to conventional primary settling on the water line. No significant differences in the pollution flow rates between primary and biological sludge were detected. Whatever the thickening and dehydration technologies that were tested, the specific quantities of microplastics along the sludge treatment lines were steady, implying the comparable behaviour of microparticular pollution to total suspended solids. These results underscored the important role of the different concentration stages of sludge treatment lines in sequestrating microplastics within the sludge fraction. Full article

The widespread presence of microplastics (MPs) is of growing concern for both the scientific community and the public. Contemporary research increasingly focuses on ecosystem transformation and global climate change. We conducted a literature review, consisting of 46 studies, to investigate the consequences of MPs’ influence on the carbon cycle in different soil types across various ecosystems. MPs can affect the cycling of carbon compounds and other biogenic elements by impacting the soil microbiome, enzyme activity, plant growth, litter decomposition, and more. The majority of authors report increased CO₂ and/or CH₄ emissions in soils containing MPs. However, some studies demonstrate the opposite or a neutral result, and the outcomes can differ even within a single study depending on the soil type and/or the type, form, and size of the MPs used. Further clarification and development of our understanding regarding the impact of MPs on the carbon cycle across different ecosystems remain crucial, taking into account the inclusion of as wide a variety of MPs as possible in future research. Full article

Cretan Graviera cheese is one of Greece’s most prized cheeses and holds a Protected Designation of Origin (PDO) status. For years, food packaging migration has been a key concern in food and health sciences, with plastics like low-density polyethylene (LDPE) and polypropylene (PP) widely used for cheese preservation and convenient handling during transport and storage. This study focused on Cretan Graviera cheese, examining two different levels of maturity: 4 and 8 months. The cheese samples were analyzed using two complementary vibrational spectroscopic techniques, FTIR-ATR and Raman spectroscopy, to assess the migration of LDPE and PP from plastic packaging to the cheese’s surface. The experimental period was set at 21 days, corresponding to the degradation time of the selected cheese, which becomes apparent after three weeks under refrigerated conditions at 7 °C. The results indicate that, with Raman and FTIR-ATR spectroscopy, LDPE and PP migration can occur from the plastic packaging to the surface of Graviera samples with different maturities. Microbial growth was observed sooner in the 4-month-old samples and 8-month-old samples. The migration of food packaging materials was confirmed using both Raman and FTIR spectroscopy, highlighting that Cretan Graviera cheese should be stored in appropriate packaging under refrigerated conditions at 7 °C. Full article

Nanoplastics and microplastics in agricultural systems have raised significant concerns due to their effects on plant health and potential risks to human consumption. This review examined these pollutants’ origins, behavior, and impacts in agricultural environments, emphasizing their primary contamination pathways, such as irrigation, plastic mulching, and sewage sludge application. It explored the transport, accumulation, and interactions of these particles in the soil, including their ability to adsorb other contaminants like pesticides and heavy metals. The effects on plant physiology and potential toxicity were highlighted, along with the implications for food quality and safety. Chronic exposure to these pollutants through the food chain posed notable health concerns for humans, emphasizing the urgency of addressing this issue. Research gaps, such as the toxicokinetics of nanoplastics and microplastics in plants and humans, were identified, underscoring the need for further investigation. The review also presented mitigation strategies, including improved waste management and the development of sustainable agricultural practices. Full article

Biscayne Bay in southeastern Florida, USA, has experienced dramatic ecological declines due to pollution. The Biscayne Bay and Southeastern Everglades Ecosystem Restoration will deliver water from a canal adjacent to coastal mangroves, intercepting pollutants before they are deposited into the estuary. Given their demonstrated capacity to filter nutrients and other contaminants from the water column, we hypothesized that mangrove wetlands also filter microplastics (“MPs”). Water and sediment samples were taken from 3 “zones”: the L-31E canal, a potential MP source; interior, dwarf mangroves; and coastal, tidal fringe mangroves. These three environments were replicated in coastal basins with and without canal culverts. MPs were expected to vary seasonally and be more abundant and larger in the dwarf zone and in low-bulk density sediments as particles settled into peat soils. In sediment, MPs were more abundant in the dry season (average 0.073 ± 0.102 (SD) MPs/g dw) before getting flushed by overland runoff resulting in greater concentrations in water during the wet season (average 0.179 ± 0.358 (SD) MPs/L). MPs were most abundant and larger in the low bulk density sediments of the dwarf zone, likely due to sheltering from fragmentation. Culvert presence had no effect, but MPs may increase as waterflows increase to planned volumes. Understanding MP dynamics enables managers to predict water quality impacts and leverage the potential ecosystem service of MP filtration by mangrove wetlands. Full article

The purpose of this study is to determine the plastic wear of the cartridge filter casing 01WTKF (Wolftechnik Filtersysteme GmbH & Co. KG, Weil der Stadt, Germany) when exposed to sand, sediment, and ice at temperatures below 0 °C, both in laboratory and field conditions. Furthermore, this study aims to discuss whether previous studies conducted with the model 01WTKF may suffer significant errors due to abrasion. The freshwater samples were collected in Finnmark, Norway. These samples were filtered using a cartridge filtration method and the 01WTKF filter casing, which features lids made of polypropylene (PP) and bottom parts made of styrene–acrylonitrile copolymer (SAN) or PP. The samples were analyzed for microplastic (MP) cross-contamination by comparing the results of the model 01WTKF to those of the stainless-steel-based model 01WTGD. Laboratory and environmental samples were examined using FT-IR spectroscopy. The results indicate that wear occurs for ice, sand, and sediment. Abrasion significantly increased the overall PP concentration in the environmental samples, introducing an error of 858 ± 516 N m⁻³ MPs to 2453 ± 92 N m⁻³ MPs. By contrast, no wear was detected for the SAN-based bottom part. For the PP-based lids, only 92 ± 83 N m⁻³ MPs were identified. Therefore, the use of PP-based bottom parts and lids is not recommended at temperatures below 0 °C. Additionally, studies utilizing the model 01WTKF should be reviewed and re-evaluated to ensure the accuracy of the obtained data. Full article

Microplastics pose a significant environmental threat, and understanding their sources and generation mechanisms is crucial for mitigation efforts. This study investigates the effects of ultraviolet intensity, temperature, and relative humidity on the degradation of polyethylene terephthalate (PET) plastics and the subsequent formation of microplastic particles. PET samples were exposed to ultraviolet (UV) radiation under various environmental conditions using the SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) accelerated weathering device at the National Institute of Standards and Technology (NIST). Attenuated total reflectance–Fourier transform infrared spectroscopy (ATR-FTIR) and laser confocal scanning microscopy (LSCM)/atomic force microscopy (AFM) were employed to characterize the chemical and morphological changes on the weathered surfaces. This study’s findings reveal that temperature and relative humidity significantly influence the rate of photodegradation and the characteristics of the generated microplastics. Higher temperatures and increased humidity accelerated the degradation process, leading to a higher abundance of microplastic particles. However, larger particles were observed at higher temperatures due to aggregation. These results underscore the importance of considering environmental factors when assessing the fate and transport of microplastics in the environment. Developing strategies to reduce plastic pollution and mitigate the generation of microplastics is essential for protecting ecosystems and human health. Full article

This study focuses on the deposition of microplastics (MPs) on urban beaches along the central São Paulo coastline, utilizing advanced methodologies such as remote sensing, GNSS altimetric surveys, µ-Raman spectroscopy, and machine learning (ML) models. MP concentrations ranged from 6 to 35 MPs/m², with the highest densities observed near the Port of Santos, attributed to industrial and port activities. The predominant MP types identified were foams (48.7%), fragments (27.7%), and pellets (23.2%), while fibers were rare (0.4%). Beach slope and orientation were found to facilitate the concentration of MP deposition, particularly for foams and pellets. The study’s ML models showed high predictive accuracy, with Random Forest and Gradient Boosting performing exceptionally well for specific MP categories (pellet, fragment, fiber, foam, and film). Polymer characterization revealed the prevalence of polyethylene, polypropylene, and polystyrene, reflecting sources such as disposable packaging and industrial raw materials. The findings emphasize the need for improved waste management and targeted urban beach cleanups, which currently fail to address smaller MPs effectively. This research highlights the critical role of combining in situ data with predictive models to understand MP dynamics in coastal environments. It provides actionable insights for mitigation strategies and contributes to global efforts aligned with the Sustainable Development Goals, particularly SDG 14, aimed at conserving marine ecosystems and reducing pollution. Full article

Microplastics (MPs) are currently a serious environmental problem, primarily due to their persistence in the environment, low concentration, and difficulty in detection and disposal. MPs have also been detected in humans and have been shown to be harmful. Although there are methodologies for their recovery or elimination in most water treatment plants, a significant portion still bypasses these elimination systems. It is this percentage that we must try to eliminate. In addition to finding new methodologies for the treatment of MPs, it is important to find new materials adapted to this process. In this context, metal–organic frameworks (MOFs) are high-versatility compounds that can be synthesized using different techniques to obtain materials with different properties, such as porosity, morphology, conductivity, etc. These materials can adsorb MPs in different ways, such as electrostatic interaction, bond formation, etc., or they can be obtained by containing metals that catalyze reactions for the formation of highly reactive species that can oxidize the MPs. This review examines how MOF materials have gained attention for the adsorption-based recovery and removal of MPs and discusses the problems associated with these materials and possible solutions. Full article

Microplastics, remnants of macroplastics that have broken down to fragments smaller than 5 mm, and nanoplastics, broken down even further to sizes < 1 μm, are pervasive in aquatic ecosystems. These plastic particles are consumed by microscopic organisms, leading to bioaccumulation up trophic levels. The accumulation of plastic in the organismal gut can result in various repercussions, including cellular contamination and genomic modifications such as DNA methylation. While methylation has been studied in teleost fishes, the impact of nanoplastic exposure on this process in any species remains largely unexplored. This study delves into this largely uncharted territory, investigating the accumulation of methylation due to nanoplastic exposure within the genome of cultured bluegill BF-2 cells (Lepomis macrochirus) using methylation-sensitive AFLPs. The methylation state was analyzed through capillary gel analysis and electropherograms. Differential methylation occurred between several control and experimental groups due to nanoplastic exposure; however, these differences were not dose- or time-dependent. These results could suggest that higher dosages and exposure times to nanoplastics do not result in increased methylation levels in congruence with the dosage and exposure time; rather, only the presence of nanoplastics is enough to cause DNA methylation changes. Full article

Rivers are recognized as major unilateral pathways of microplastic transport between terrestrial and marine ecosystems, yet our understanding of their dispersal patterns over space and through time as they migrate from source to sink is limited. In this study, surface water samples were collected monthly from 12 sites along an urban ephemeral river (Leon Creek) in San Antonio between June 2021 and May 2022 to characterize and evaluate the spatiotemporal distribution of microplastics. Microplastics were found in all sites throughout the monitoring timeframe. The mean abundance of microplastics varied from 3.21 to 26.8 items/L. Surface waters consistently contained microplastics during months of dysconnectivity, suggesting atmospheric deposition as a considerable contributive variable. Contrary to prior studies of perennial systems, ephemeral pools and reaches showed no correlation between MP concentration and season precipitation. Fibers were the most abundant (~87%) morphology followed by foams (7%). This study is the first to report microplastics in ephemeral streams, suggesting that different environmental variables may be responsible for microplastic dynamics in intermittent river and ephemeral stream systems and headwater tributaries of major rivers. As the global extent of IRES systems is projected to increase with continued climate change, understanding such systems’ influence on MP spatial distribution and fluvial transport regimes constitutes valuable information in assessing MP pathways and their fate as a part of the global “Plastisphere” geochemical cycle in the Anthropocene. Full article

Rubber materials enter aquatic environments by stormwater runoff via sources such as playground mulch, athletic fields, and roadway surfaces. Tire rubbers are considered plastics as they comprise a substantial portion of synthetic polymers. Rubber particles are complex and variable depending on the type, source, and age of rubber. In this study, zebrafish embryos and daphnids were exposed to nano-scale or micro-scale particles, or leachate from recycled rubber (RR), crumb rubber (CR), and cryo-milled tire tread (CMTT). Zebrafish embryos were evaluated for lethal and sub-lethal effects over a 120 h exposure, while daphnids were tested over a 48 h period. Nano-scale RR, CR, and CMTT particles elicited a hatch delay in zebrafish embryos with similar EC₅₀ values (1.3 × 10⁹–1.4 × 10⁹ particles/mL). Micro-scale particles did not elicit any significant effects in developing zebrafish. Nano-scale particles of all rubber materials significantly increased hatch delay compared to leachate, suggesting an adverse nanoparticle effect unexplained by chemical leaching alone, indicating tire particle-specific effects. Daphnia RR micro- and nanoparticle exposures resulted in mortality, with LC₅₀ values of 9.8 × 10⁵ microparticles/mL and 5.0 × 10⁸ nanoparticles/mL, respectively. Leachate exposures did not elicit significant Daphnia mortality. Sublethal micro- and nano-TP exposures significantly decreased microalgae ingestion by Daphnia after 24 h. The effects of tire-derived exposures observed pose a risk to aquatic organism survival at environmentally relevant concentrations. Full article

Biodegradable materials are emerging as a sustainable alternative to conventional petroleum-based plastics across packaging, sanitation, and agriculture sectors. These materials naturally decompose into harmless substances within a specified period, completing an eco-friendly lifecycle. However, the widespread adoption of biodegradable plastics depends on building confidence among consumers, manufacturers, and regulators regarding their effectiveness. This study employed a mixed-methods approach to investigate the key factors influencing biodegradable plastics’ sustainability, integrating theoretical frameworks with survey data collected from Malaysian plastic users aged 15 and above. Results revealed that individual characteristics, particularly environmental self-identity, significantly influence behavioural intentions toward sustainable practices, such as choosing eco-friendly packaging. The findings contribute to the theoretical understanding of biodegradable plastics adoption in developing markets while providing actionable insights for government and corporate stakeholders. This study recommends targeted awareness campaigns emphasising environmental self-identity to reduce conventional packaging use and promote biodegradable alternatives. By incorporating these identity-focused messages into marketing communications, organisations can enhance public awareness and market perception of biodegradable products. Full article

Microplastics (MP) are ubiquitous contaminants in diverse environmental matrices, including biota. Urban birds, such as pigeons (Columba livia), are particularly vulnerable to MP exposure due to their scavenging habits and proximity to human activities. This study developed and applied a methodology to assess MP presence in pigeon feces, starting with a review of existing methods for extracting MPs from organic matrices. Of all the methodologies investigated, a method was established to be tested, varying the reagent, using pigeon feces collected from the Universidad Autónoma Metropolitana, Azcapotzalco Unit (UAM-A) and 15 virgin microplastics of five different types. Of both reagents, it was found that the method with 50% H₂O₂ presented better results (degradation of almost all organic matter and recovery efficiency of 93.33%). The selected method was optimized before being applied to feces collected from three sites in Mexico City (n = 10 samples per site). MPs were extracted using a digestion process with 50% hydrogen peroxide, flotation test with CaCl₂, staining with red Nile dye and vacuum filtration and analyzed by microscopy and FTIR. Concentrations ranged from 16.4 to 27.8 MP/g dry feces, with fragments (80%) and fibers (20%) being the predominant shapes. The most common colors were black (32%) and white (22%), the polymers identified included polystyrene and polyethylene and the most common size was < 1 mm (54%). These findings suggest that pigeons ingest MP during feeding, likely due to confusion with organic matter, highlighting the risks of urban plastic pollution to avian health. The ingestion of MPs could lead to malnutrition, organ damage, and ecosystem imbalances, underscoring the need for improved waste management in urban areas. This study provides evidence of the pervasive impact of plastic pollution in non-marine environments, demonstrating the potential of urban birds as bio-indicators of local contamination. Full article

Microplastics (MPs) are plastic particles ranging from 1000 to 5000 µm in diameter, posing a growing environmental and health risk. Composting is an excellent way to add nutrient-rich humus to the soil to boost plant development, but it also pollutes agricultural soil with MPs. Previous research has shown that MPs can threaten plant development, production, and quality, hence they must be studied. This study examined how a mixture of three MP types—polyethene (PE), polystyrene (PS), and polypropene (PP)—affected greenhouse tomato plant development. MP types were spiked at 1% w/w (MPs/soil) in tomato pots, whereas non-spiked growth medium was the control. Statistical analysis was conducted using an analysis of variance (ANOVA) and Tukey’s test (95% confidence) to compare treatments and controls. Soil spiked with MPs increased chlorophyll content (SPAD), transpiration rate, photosynthetic rate, and stomata conductance by 5.16%, 16.71%, 25.81%, and 20.75%, respectively, compared to the control but decreased sub-stomata CO₂ concentration by 3.23%. However, MPs did not significantly affect tomato plant morpho-physiological features (p > 0.05). Biochemical analysis of tomato fruits showed significant (p < 0.05) reduction effects of MPs on carotenoid, total flavonoid, and sugar but increased protein, ascorbate, and peroxidase activity. However, there was no significant difference (p > 0.05) in the effects of the combined MPs on total phenolic content. These data imply that whereas MPs did not influence tomato plant physiological and morphological properties, tomato fruit biochemistry was reduced. This raise concerns that an increase in MPs in soils may reduce antioxidant content and negatively affect human health contributing to a decrease in food security. Full article

Micro-nano plastics (MNPs) are emerging environmental and food contaminants that are raising serious health concerns. Due to the polycontamination of the food web with environmental pollutants (EPs), and now MNPs, the co-ingestion of EPs and MNPs is likely to occur, and the potential synergistic effects of such co-ingestions are completely unstudied. In this study, we therefore sought to determine the effects of the two model EPs, arsenic and boscalid, on the uptake and toxicity of two model MNPs, 25 and 1000 nm polystyrene (PS-25 and PS-1000), and vice versa, employing a triculture small intestinal epithelium model combined with simulated digestion. In 24 h triculture exposures, neither MNPs, EPs, nor MNPs + EPs caused significant toxicity. The presence of PS-25 significantly increased arsenic uptake (from 0.0 to 5.8%, p < 0.001) and translocation (from 5.2 to 9.8%, p < 0.05) but had no effect on boscalid uptake or translocation, whereas PS-1000 had no effect on the uptake or translocation of either EP. The uptake of both PS MNPs was also increased by EPs, rising from 10.6 to 19.5% (p < 0.01) for PS-25 and from 4.8 to 8.5% (p < 0.01) for PS-1000. These findings highlight the need for further studies to assess MNP-EP interactions and possible synergistic adverse health impacts. Full article

Technical retrofit Sustainable Drainage Systems (SuDSs) are a suitable option in the numerous mitigation measures to reduce the amount of tyre wear entering the environment. In the study presented here, such a filter system was tested under extreme conditions at the ADAC Driving Safety Centre Berlin-Brandenburg. Despite a technical separation limit of 125 or 250 µm of the filter systems, particles > 6 µm were measured in the retained masses. In addition, the marker SBR was used to determine the residues of tyre wear in the filter system using the TED-GC-MS analysis method. The highest concentrations were found in the 20–63 µm fraction. The results indicate that tyre wear particles become smaller due to high forces generated by braking and cornering. Test stand investigations indicate a retention efficiency of the filter system of 2/3 of the tyre wear. Furthermore, the results show that the parameter ‘Total Suspended Solids < 63 µm’ (TSS₆₃) is a relevant evaluation parameter for the road runoff. Full article

This study addresses the pressing need for standardized methodologies to quantify microplastics (MPs) within the fine fraction of municipal solid waste (MSW), often overlooked despite its potential environmental impact. Five extraction protocols were evaluated to identify the most effective method for isolating MPs in fine waste. These were specifically applied to samples from the Universidad Autónoma Metropolitana and one transfer station in Mexico City. A potassium hydroxide digestion protocol with subsequent flotation and centrifugation steps achieved optimal results, ensuring complete organic matter degradation and high microplastic recovery. Subsequent analyses revealed notable concentrations of MPs, primarily fragments and fibers, with higher abundance at the university site. Statistical tests confirmed significant differences between the sample sites. These findings highlight the vulnerability of MSW fine fractions to microplastic contamination and underline the importance of targeted waste management strategies. This research contributes to understanding microplastic behavior in waste management systems and emphasizes the need for mitigation efforts to prevent environmental contamination. Full article