Microplastics, Volume 4, Issue 1 (March 2025) – 5 articles

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

Nanoplastics (NPs) and microplastics (MPs) are an emerging threat to global health. They negatively impact ecosystems and many physiological processes, causing alterations in xenobiotic metabolism, nutrient uptake, energy metabolism, or cytotoxicity. In humans, we are beginning to analyze these plastics for the mechanisms by which they enter the organism, accumulate, and diffuse as well as for their pathogenic potential. NP accumulation has been demonstrated in human tissues, such as blood or placenta, while in others it remains largely unstudied. In this work, we detected NP accumulation in bronchoalveolar lavage fluids (BALFs), cerebrospinal fluids (CSFs), lymph nodes (LNs), urine, pleural fluids (PFs), ascitic fluids (AFs), and peripheral blood (PB) by combining fluorescence and nanocytometry techniques. NP analysis was compared with two strains of mice, and the results support that inhalation is the main route of NP accumulation. Full article