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In recent years, microplastics (MPs) have attracted worldwide attention as emerging pollutants, and wastewater treatment plants are among the environment's most important sources of MPs. This study aimed to summarize MPs effects on various aspects of sludge systems. The results showed that MPs inhibited substance transformation in sludge systems, with greater inhibition observed at higher concentrations and smaller MP particle sizes. Moreover, low concentrations of MPs promote extracellular polymeric substance (EPS) secretion, whereas high concentrations suppress EPS secretion, destroying the sludge structure. Granular sludge systems exhibit higher resistance to MPs than activated sludge systems owing to their layered structures. Micrometer-sized MPs primarily inhibit the dewatering performance of activated sludge through physical crushing, while nano-sized MPs primarily affect sludge dewatering through biological effects. However, for granular sludge system, micrometer-sized MPs were unable to penetrate the granular sludge interior, their affinity and aggregation capabilities enabled them to accumulate on the sludge surface. In contrast, nano-sized MPs can enter the interior of granular sludge and impair mass-transfer pathways, ultimately resulting in toxic effects. Furthermore, MPs induce various toxic effects in sludge systems (single and combined toxic effects). These toxic effects affect the expression of key enzymes and functional genes, leading to changes in microbial communities. Because of the layered structure of granular sludge systems, MPs may initially affect the microbial community structure outside the granules, with less impact on the internal microorganisms. However, the specific mechanism still needs to be explored. Finally, this study presents research questions and directions that require further investigation. [ABSTRACT FROM AUTHOR]

In order to examine the distribution and accumulation patterns of microplastics (MPs) in conjunction with effective microorganisms (EMs), as well as their collective impact on oxidative stress, inflammatory damage, and immune regulation in juvenile Micropterus salmoides (M. salmoides), a series of exposure (96 h) and depuration (D 96 h) experiments with MPs and EMs were conducted. The results showed that the highest abundance of MPs appeared in the biological samples in the EMs with MPs group (EP group) at 96 h. The highest abundance of MPs in the sediment occurred in the MPs group (P group) at 96 h with 507 items/mL and in the water samples at 48 h in the P group with 141.75 items/mL. The addition of EMs increased the content of MPs in the intestine of M. salmoides and reduced the MPs content in the water and sediment. The expression of Nrf2 and SOD in the intestinal in the EP group compared with the control group (C group) showed significant differences at 48 h. After D 96 h, the expression of SOD and GPX in the MPs + EMs (P-E) (EP group) was significantly higher than the C group. IL-8 and TNF-α in the intestine and gill in the P group were significantly higher than the C group at 96 h, and it began to show a decreasing trend after D 96 h. These results revealed that the addition of EMs increased the enrichment of MPs in M. salmoides, while it promoted the recovery of M. salmoides from adverse effects during the depuration phase. These findings can help us understand the responses of MPs with microorganisms in aquaculture. [ABSTRACT FROM AUTHOR]

[Objective]Exploring the migration characteristics of microplastics under rainstorm runoff and water infiltration in sloping lawns, providing a basis for estimating the interception of microplastics in lawns and selecting urban lawns. [Methods]The characteristics of microplastic migration with runoff and vertical migration in soil of three kinds of sloping grassland were studied on runoff plots by artificial simulation of multiple rainstorms. [Results]The vast majority of microplastics remained in the grassland. The migration quantity of microplastics changed with the increase and decrease of runoff, but the migration of microplastics in the stable stage of runoff showed a fluctuating downward trend. With the increase of rainfall events, the migration and fluctuation of microplastics decreased significantly. The runoff migration increased with the decrease of microplastic particle size, but there was no difference in the migration of microplastics when the particle size was less than 0. 5 mm. The vertical migration depth of microplastics concentrated within 15 cm. With the increase of rainfall, the depth did not increase significantly. The particle size of microplastics with vertical migration was mainly＜0. 25 mm, and the migration amount below 10 cm was less than 1％of 0-5 cm. The microplastics in 0-5 cm soil leached in the uphill position and enriched in the downhill position. [Conclusion]Short-term rainfall causes less horizontal and vertical migration of microplastics, and the migration of microplastics in white clover grassland is the least, is the most in ryegrass grassland, and the horizontal migration and vertical migration in Bermuda grass are in the middle. [ABSTRACT FROM AUTHOR]

Given the growing urge for plastic management and regulation in the world, recent studies have investigated the problem of plastic material identification for correct classification and disposal. Recent works have shown the potential of machine learning techniques for successful microplastics classification using Raman signals. Classification techniques from the machine learning area allow the identification of the type of microplastic from optical signals based on Raman spectroscopy. In this paper, we investigate the impact of high-frequency noise on the performance of related classification tasks. It is well-known that classification based on Raman is highly dependent on peak visibility, but it is also known that signal smoothing is a common step in the pre-processing of the measured signals. This raises a potential trade-off between high-frequency noise and peak preservation that depends on user-defined parameters. The results obtained in this work suggest that a linear discriminant analysis model cannot generalize properly in the presence of noisy signals, whereas an error-correcting output codes model is better suited to account for inherent noise. Moreover, principal components analysis (PCA) can become a must-do step for robust classification models, given its simplicity and natural smoothing capabilities. Our study on the high-frequency noise, the possible trade-off between pre-processing the high-frequency noise and the peak visibility, and the use of PCA as a noise reduction technique in addition to its dimensionality reduction functionality are the fundamental aspects of this work. [ABSTRACT FROM AUTHOR]

Plastic pollution is one of today's most serious global issues in the aquatic environment and organisms, including entanglements, ingestion, and possible toxicity. The study was carried out to screen and identify the microplastics in some tissues of fish species from Sallari and Hauren Shanu burrow pits in Kano metropolis. A total of 60 fish samples comprising two species; Oreochromis niloticus (n = 30) and Tilapia zilli (n = 30), were collected from sampling sites (Sallari and Hauren Shanu). The fishes' gastrointestinal tract, gills and muscle tissues were collected, screenedand examined using a dissecting microscope for the presence of microplastics. Microplastics were found in all the examined fish tissue samples from both sites. In the samples from Hauren Shanu, 63% of the fish had microplastics in the gastrointestinal tract, 46% in muscle and 36% in the gills. In samples from Sallari, 33% of the fish had microplastics in theirgastrointestinal tract, 16% in muscle and 23% in the gills. Microplastics which include fibers, fragments, microbeads and tyre-dusts were observed in all the examined tissues of Oreochromis niloticus and Tilapia zilli although not significantly different (p > 0.05) between the fish species. The study demonstrates microplastics presence in the fish species and portrays to a large extent some degree of plastic contamination in Hauren shanu and Sallari burrow pits. Further assessments should be done on human food contamination by microplastics and their effects on human health. [ABSTRACT FROM AUTHOR]

Microplastics (plastic particles <5 mm) permeate aquatic and terrestrial ecosystems and constitute a hazard to animal life. Although much research has been conducted on the effects of microplastics on marine and benthic organisms, less consideration has been given to insects, especially those adapted to urban environments. Here, we provide a perspective on the potential consequences of exposure to microplastics within typical larval habitat on mosquito biology. Mosquitoes represent an ideal organism in which to explore the biological effects of microplastics on terrestrial insects, not least because of their importance as an infectious disease vector. Drawing on evidence from other organisms and knowledge of the mosquito life cycle, we summarise some of the more plausible impacts of microplastics including physiological, ecotoxicological and immunological responses. We conclude that although there remains little experimental evidence demonstrating any adverse effect on mosquito biology or pathogen transmission, significant knowledge gaps remain, and there is now a need to quantify the effects that microplastic pollution could have on such an important disease vector. [ABSTRACT FROM AUTHOR]

This review reports a discussion involving sources, adverse effects, and quantification of emerging contaminants that have polluted the environment, such as chemical elements employed in medicine (antimony, barium, and gadolinium), microplastics in water bodies, in addition to pharmaceutical, illicit drugs, and their metabolites in wastewater and sewage sludge. It also addresses the pollution caused by emerging contaminants in urban areas, such as gas stations and hairdressing salons. The main analytical methods recommended for determining all these contaminants are briefly reported. [ABSTRACT FROM AUTHOR]

Microplastics are micrometre-sized emerging pollutants produced by plastic fragmentation. They have been recently detected in most ecosystems, even in remote areas. Here, we review microplastics with emphasis on sources, occurrence, transport, detection methods, policies, toxicity, and management methods. In the transport section, we discuss sorption kinetics, layered microplastics, and influencing factors such as biofilm formation. Microplastic management can be done by adsorption, filtration, oxidation, and biodegradation. Microplastic interaction is influenced by temperature, pH, salinity, and dissolved organic matter. [ABSTRACT FROM AUTHOR]

Microplastics are emerging contaminants that have been detected recently in most environmental and biological systems, yet their health risk for humans has not been clearly summarized. Here we review human health risk associated with exposure to microplastics with focus on methods of exposure assessment, hazard identification, dose–response assessment, exposure assessment, and risk characterization. Hazards include direct hazards, hazards from contaminants released by microplastics, and hazards from microplastic interactions with surrounding contaminants. Microplastics trigger oxidative stress, disrupt metabolism, interfere with gut microflora and gastrointestinal functions, disrupt hepatic, cardiopulmonary and immune systems, and degrade reproductive health. Some additives leached from microplastics such as phthalates are endocrine disruptors and thus impact reproductive health. The interaction of microplastics with other pollutants in the environment induces varied hazards following synergistic or antagonistic effects. [ABSTRACT FROM AUTHOR]

Mangroves, a major ecosystem for carbon sequestration, have been recently identified as a microplastic sink, yet the impact of microplastics on the mangrove microbial community is poorly known. Here, we investigated the metabolic activities of mangrove rhizosphere microbiome in the presence of polyethylene, polystyrene, polyamide, and polyvinylchloride, in microcosms, using Biolog™ Ecoplates. Results show that microbial communities in mangrove sediment hold their functional diversity and comprehensive metabolic activity within 56 days of microplastic exposure. However, polyamide and polyvinylchloride microplastics induced a 59.6–66.7% reduction in the rhizosphere microbes' utilization for their preferred polymer carbon sources. Microbes exposed to polyethylene microplastics showed an activated biotransformation for nitrogen-contained carbon sources. Polyethylene and polyamide microplastics caused a 20.1–22.4% loss available nitrogen. Overall, microplastics are altering the carbon and nitrogen metabolism activities of microbiomes in mangrove wetlands. [ABSTRACT FROM AUTHOR]

The global plastic production has steadily increased from 1.7 million tons in 1950 to over 400 million tons in 2022, with about 60% of plastic ultimately ending up in landfills and oceans. There is also growing evidence that microplastics exert negative effects on biota and ecosystems. Biodegradable plastics may represent a safe alternative, yet their potential adverse effects have not been comprehensively analyzed. Here, we reviewed biodegradable plastics, with focus on their conversion into microplastics, their interactions with pollutants, and their combined toxicity for aquatic biota. Biodegradable plastics include polylactic acid, polyhydroxyalkanoates, polybutylene succinate, poly(butylene adipate-co-terephthalate), and poly(ε-caprolactone). We found that some biobased plastics are hardly biodegradable. Some biobased plastics are compostable but require specific environmental conditions for their biodegradation. Biobased plastics can generate microplastics when released into the environment, which can impact biota. Contrary to the common public belief, biodegradable plastics may not only originate from biosources but can be synthesized from fossil fuels. Microplastics originating from biodegradable plastics can interact with pollutants, adsorbing and transporting these pollutants, resulting in synergistic or antagonistic effects on exposed organisms. Biofilm formation on microplastics impacts their degradation and pollutant interactions. [ABSTRACT FROM AUTHOR]

Ocean pollution by microplastics represents a threat to phytoplankton health, yet there is few knowledge on physical interactions between microplastics and microalgal cell surfaces. We studied the contact between environmentally aged microplastics and four microalgal species by atomic force microscopy. After seven days, microalgae showed malformations at specific sites, and these malformations varied with species. Depending on whether the cell had a porous or a smooth surface, microplastics adsorbed to the cell surface via embedding or denting, leading to minor defects or noticeable wrinkles in cell walls. Results also showed that microplastics penetrate into microalgae. Such cellular engulfment of microplastics was less present in typical diatoms because diatoms bear a porous frustule capable of trapping tiny particles. Moreover, we observed a novel type of deformation, bowl-shaped depressions, only in non-porous microalgae. The geometric features of malformations are correlated with the shape and size of microplastics. Our findings reveal for the first time the species-specific deformation in microalgae due to microplastic exposure. [ABSTRACT FROM AUTHOR]

Microplastics (MPs), ever since they were identified as a potential and widely distributed persistent contaminant, the number of studies highlighting their impacts on various terrestrial ecosystems have been increasing. Recently, the effect of MPs on the agricultural ecosystem has gained momentum. Hence, the present review examines the impact of microplastics on agricultural crop systems and the mechanism underlying its toxicity. The current review revealed that most of the studies were conducted at a laboratory scale and under controlled conditions. Additionally, it was observed that polystyrene (PS) followed by polyethylene (PE) are the most studied polymer type, while the most studied plants are wheat and maize. Hitherto, literature studies suggest that the microplastics' influence on plant growth can be negative or sometimes neutral; while in some cases it exerts a hormetic effect which depends on other factors determining plant growth. Notably, the main mechanisms through which microplastics influence plant growth are mechanical damage, alteration of soil properties, or by leaching of additives. Overall, with burgeoning research interest in this aspect, the current review has significant implications for the toxicity of MPs on plants and throws light on the need to develop novel guidelines toward the sustainable use of plastics in agricultural sector. However, realistic field-level studies and estimating the MPs concentration at various region are essential to develop remediation approaches. Future studies should also focus on translocation and accumulation of micron sized MPs in edible portion of crops and their effect on food safety. Although several papers on various elements of microplastics in terrestrial ecosystems have recently been published, there is currently no comprehensive review focusing on the effect of microplastic contamination in plants. Furthermore, no review has conducted a meta – analysis indicating the most commonly reported source, methods to identify the MPs in plants, majorly reported polymer type, widely studied plant species and the mechanism underlying in its toxicity. Hence, this review mainly focuses on edible/economically important crops and highlights the impacts of microplastics on different plant parameters i.e., seed germination, root and shoot growth, photosynthesis, nutrient metabolism, oxidative damage and genotoxicity and mechanisms through which microplastics affect plant growth. [ABSTRACT FROM AUTHOR]

Microplastic-derived dissolved organic matter (MP-DOM) exerts great effects on organic carbon pool and its environmental behaviors in natural waters due to increasing amounts of uncontrolled plastic disposal. However, systematic understanding of chemical composition and environmental impacts of MP-DOM in aquatic systems was limited. In this work, the chemical and molecular structures of MP-DOM derived from diverse characterization methods were examined and synthesized to provide a basis for understanding their environmental processes. Additionally, those factors affecting the quantity and quality of released MP-DOM (e.g., plastic types, water environments, and external weathering conditions) were reviewed. Furthermore, environmental behaviors of MP-DOM including its biological degradation, adsorption on mineral surfaces, and interaction with pollutants, as well as their environmental impacts were comprehensively summarized. Finally, we outlooked the future research directions on MP-DOM studies, aiming to contribute to a deeper understanding of the environmental mechanisms and control of plastic pollution through the analysis of MP-DOM. This review provides information for further understanding the impact of microplastics on natural water, which might have consequences on the fluxes of carbon and biogeochemical behaviors of metal and organic contaminants. The structural features, influence factors, and biogeochemical behavior of MP-DOM were reviewed. Compared with NOM, MP-DOM is dominated by labile aliphatic compounds. UV exposure, high temperature and alkalinity solution could promote MP-DOM release. MP-DOM actively interacts with environmental media and alters their environmental fate. [ABSTRACT FROM AUTHOR]

[Display omitted] • First study regarding MP pollution in plastic recycling facilities in Türkiye. • Plastic recycling facilities are discharging reaches up to 58,468 MP/L. • Low density and lower sized MPs can sink with the adsorbed pollution in washing unit. • OpenSpecy increased the hit qualities of polymers in identification of MPs. There is little knowledge about microplastic (MP) pollution in plastic recycling facility (PRF) wastewater. In this study, MPs in the wastewaters of four PRFs located in Türkiye were characterized for size, shape, color, and polymer types after sieving from 5,000 µm to the lowest 75 µm with seven sieves. The wet peroxide oxidation procedure was applied before attenuated total reflectance fourier transform infrared spectroscopy analysis for polymer identification. Polyethylene, and polypropylene were the dominant (75 % of total count) MP types within 22 polymer types. Average hit qualities of polymers increased from 69 % to above 84 % for the device software (OPUS) and open software (OpenSpecy). The abundance of MPs was determined as 53,987 MPs/L and 0.8 g MP/L for mixed PRFs 7,582 MPs/L and 4.6 g/L for the LDPE recycling facility, and 2,196 MPs/L and 0.06 g MPs/L for the granulation cooling water by count and weight, respectively. Small-sized MPs are found in the bottom sample much more than the surface and effluent samples in the washing tank. This indicated that MPs adsorbed the pollutants settled in the washing tank due to adsorbed pollution/biofilm. A maximum of 4.6 kg MP/ton of plastic recycled can be discharged as MPs that can be recovered. Considering the plastics recycling capacity, discharged MPs in these PRFs are possibly above 30,000 tons. [ABSTRACT FROM AUTHOR]

The production, dispersal, and accumulation of microplastics (MPs) are interconnected with climate change. Plastic production, which involves fossil resources like oil, generates greenhouse gas emissions during extraction and processing, contributing to global warming. Simultaneously, climate change influences the dispersion, fragmentation, and accumulation of MPs; extreme weather events facilitate plastic transport to the sea and natural environments. The increasing environmental impact of MPs poses a global challenge. This review focuses on the dispersion of MPs due to climate change, with attention given to the "One Health" approach. This promotes interdisciplinary collaboration, recognizing the interrelationship of human, animal, and ecosystem health. Crucial for a broad perspective on global health, the "One Health" approach emphasizes the need to understand and address MPs in the environment. In conclusion, implementing protocols for health monitoring and educating the public on responsible plastic management are essential. These preventive indications can help mitigate the effects of MPs, promoting a sustainable lifestyle from a One Health perspective. [ABSTRACT FROM AUTHOR]

Microplastic occurrence in the aquatic ecosystem has become of great concern worldwide because of its persistence, durability, and toxicity. Microplastics are found ubiquitous in freshwater environments, including rivers. Thus, our study assesses microplastic pollution in water, sediment, and fish of the Kahayan River, Indonesia. We first evaluated microplastics’ occurrence, abundance, and characteristics in Central Kalimantan, Indonesia. The average abundance of microplastic in water was 2.92 ± 2.62 items/L, while in sediment was 6.93 ± 3.15 items/Kg dry weight. We found 53 out of 90 fish (58.89%) had microplastics in their digestive tracts with an average abundance of 2.03 ± 3.416 items/Ind. The predominant characteristics in water were fragment and fibre and size of 150-<300 µm. Microplastics present in the sediment and the digestive tract of fish have similar dominant fibre. In terms of size, sediments and fish were dominated by 150-<300 µm, 1000–5000 µm, and 500-<1000 µm respectively with different order of proportions. The infrared spectroscopic analysis confirmed the most common polymer type to be polyvinyl chloride in water and sediment, while polyethylene was predominant in fish. Our study provides the current status of microplastic contamination for further evaluation and management of the Kahayan River, Indonesia. [ABSTRACT FROM AUTHOR]

A growing body of literature is raising concerns about the spread of nano‐ and microplastics and the hazards they pose to the environment and on human health. There is still a limited understanding of their sources and formation mechanisms, making their release and uptake difficult to track and quantify. Among the obstacles to the progress in this field there is the lack of reliable methods for quantitative studies, leading to a potential underestimation of the extent of their release and the related risks. In this paper, the application of an optical method for studying the release of sub‐micrometric plastics in water by polypropylene containers certified for alimentary use is described. The results show evidence of negligible release when the temperature of the water is kept below the manufacturer's specifications, whereas a rampant increase occurs beyond these conditions, irrespective of the thermal history of the sample. Particles with a diameter distribution that spans one order of magnitude are observed, ranging from ≈200 nm to 2 µm, and their refractive index and shape is characterized with light scattering measurements. This work focuses on particle release and does not assess toxicity or effects on living organisms. [ABSTRACT FROM AUTHOR]

AbstractMicroplastics, an environmental contaminant, can directly harm aquatic organisms and alter the toxicity and availability of other pollutants. The herbicide glyphosate (N-(phosphonomethyl) glycine) exerts its toxicity by inhibiting 5-enol-pyruvyl-shikimate-3-phosphate synthase (EPSPS), a key enzyme belonging to shikimic acid pathway that leads to the biosynthesis of aromatic amino acids; tolerance, instead, is dependent on a glyphosate -resistant EPSPS. We tested the effects of 0,2mM glyphosate alone and in combination with 170 mg/mL polyethylene microplastics (MPs) on the expression of EPSPS and chorismate synthase (ChS) on a culture of the cyanobacterium Limnospira maxima. Glyphosate caused the highest mortality after one week, with the resistant population surviving thereafter.However, when the culture was exposed to the combined treatment the mortality decreased. Proteomic profiles of treated cultures demonstrated that both enzymes were accumulated during the 21 days glyphosate treatment, suggesting that the surviving population of L. maxima might express glyphosate-resistant target enzymes. Treatment with combined solution caused a decrease of EPSPS and ChS levels compared to those of glyphosate alone. Our results strongly suggest that microplastics mitigate the toxicity of glyphosate towards target enzymes of the shikimic acid pathway, thereby increasing the resistance capacity of the L. maxima strain. [ABSTRACT FROM AUTHOR]

Increasing demand for size-resolved identification and quantification of microplastic particles in drinking water and environmental samples requires the adequate validation of methods and techniques that can be used for this purpose. In turn, the feasibility of such validation depends on the existence of suitable certified reference materials (CRM). A new candidate reference material (RM), consisting of polyethylene terephthalate (PET) particles and a water matrix, has been developed. Here, we examine its suitability with respect to a homogeneous and stable microplastic particle number concentration across its individual units. A measurement series employing tailor-made software for automated counting and analysis of particles (TUM-ParticleTyper 2) coupled with Raman microspectroscopy showed evidence of the candidate RM homogeneity with a relative standard deviation of 12% of PET particle counts involving particle sizes >30 µm. Both the total particle count and the respective sums within distinct size classes were comparable in all selected candidate RM units. We demonstrate the feasibility of production of a reference material that is sufficiently homogeneous and stable with respect to the particle number concentration. [ABSTRACT FROM AUTHOR]

Detecting, separating, and characterizing airborne microplastics from other airborne particulates is currently challenging due to the various instrumental constraints and related sample preparation hurdles that must be overcome. The ability to measure these real-world environments is needed to better assess the risks associated with microplastics. To that end, the current study focused on developing a methodology for sampling and characterizing airborne microplastics. Particulate sampling was carried out at a municipal materials recovery facility near a conveyer belt containing sorted plastic materials to collect airborne environmental particles on filters. Nucleopore filters were mounted on Teflon support rings, coated with 100 nm aluminum to reduce the background signal for micro-Raman spectroscopy, and marked with a fiducial pattern using a laser engraver. The fiducial pattern was crucial in identifying samples, relocating particles, and efficiently enabling orthogonal measurements on the same samples. Optimum sampling conditions of 2 h at 25 L/min were determined using light microscopy to evaluate the particle loadings. The filters were then cut into slices which were attached to sections of thin beryllium-copper sheeting for easy transfer of the filter between microscopy platforms. Scanning electron microscopy was used to identify carbon-rich particles. Light microscopy was used to identify colored particles which were also carbon-rich which were then analyzed using micro-Raman spectroscopy to identify specific polymers. [ABSTRACT FROM AUTHOR]

Pollution from microplastics (MPs) and nanoplastics (NPs) has gained significant public attention and has become a serious environmental problem worldwide. This review critically investigates MPs/NPs' ability to pass through biological barriers in vertebrate models and accumulate in various organs, including the brain. After accumulation, these particles can alter individuals' behaviour and exhibit toxic effects by inducing oxidative stress or eliciting an inflammatory response. One major concern is the possibility of transgenerational harm, in which toxic consequences are displayed in offspring who are not directly exposed to MPs/NPs. Due to their large and marked surface hydrophobicity, these particles can easily absorb and concentrate various environmental pollutants, which may increase their toxicity to individuals and subsequent generations. This review systematically provides an analysis of recent studies related to the toxic effects of MPs/NPs, highlighting the intricate interplay between co-contaminants in vitro and in vivo. We further delve into mechanisms of MPs/NPs-induced toxicity and provide an overview of potential therapeutic approaches to lessen the negative effects of these MPs/NPs. The review also emphasizes the urgency of future studies to examine the long-term effects of chronic exposure to MPs/NPs and their size- and type-specific hazardous dynamics, and devising approaches to safeguard the affected organisms. • Vertebrate organ response and degree of internalisation of MPs/NPs depends on the surface charge and size of particles • MPs/NPs can cross blood-brain barrier and induce behavioural alterations in fish and rodent model after accumulation • Presence of different polymers of MPs/NPs has been reported in human samples mainly blood, urine, and placenta • These particles may exhibit physiological and molecular changes by inducing oxidative stress and inflammatory responses • It may show antagonistic or synergistic effects with other co-contaminants or underlying biological conditions [ABSTRACT FROM AUTHOR]

Recently, spICP-MS analyses of microplastics have demonstrated that the detection capabilities of ICP-MS are sufficient to determine the size and composition of such materials. However, solution nebulization or microdroplet generation limits the sizes of droplets, microparticles, or cells that can be efficiently introduced into commonly used horizontal ICP-MS configurations. Therefore, we introduced the development of a downward-pointing ICP coupled to a time-of-flight mass spectrometer (ICP-TOFMS), which enables quantitative transport of large microdroplets (diameters up to 90 µm) into the ICP. Here, we report the capabilities of downward ICP-TOFMS for the quantitative analysis of single cells and microplastic particles. For calibration of element mass amount per particle or cell, microdroplets (70 µm diameter) composed of multielement solutions were measured by ICP-TOFMS. Microplastic beads (polystyrene) and spleenocyte cells were then also embedded in microdroplets and measured by ICP-TOFMS with ion optics optimized to determine the signals from 12C+ and other isotopes of interest, including 140Ce, 153Eu, 165Ho, and 175Lu from the REE beads and 31P for the cells. The results achieved using the prototype instrument of a vertical downward-pointing ICP-TOFMS demonstrate that such a plasma configuration is well suited to analyze microplastics and single cells. For single microbead and cell analyses, the critical mass for carbon was 4.8 pg, and the mean determined carbon mass amounts were 14 and 23 pg, respectively. For the microbead analysis, the detected carbon mass corresponds to a particle diameter of 2.93 ± 0.24 µm, which is consistent with the scanning (transmission) electron microscopy–determined diameter of 2.97 ± 0.04 µm. Furthermore, in the analysis of spleenocyte cells, carbon and phosphorus masses were determined to be correlated. [ABSTRACT FROM AUTHOR]

The overproduction and mismanagement of plastics has led to the accumulation of these materials in the environment, particularly in the marine ecosystem. Once in the environment, plastics break down and can acquire microscopic or even nanoscopic sizes. Given their sizes, microplastics (MPs) and nanoplastics (NPs) are hard to detect and remove from the aquatic environment, eventually interacting with marine organisms. This research mainly aimed to achieve the aggregation of micro- and nanoplastics (MNPs) to ease their removal from the marine environment. To this end, the size and stability of polystyrene (PS) MNPs were measured in synthetic seawater with the different components of the technology (ionic liquid and chitosan). The MPs were purchased in their plain form, while the NPs displayed amines on their surface (PS NP-NH2). The results showed that this technology promoted a significant aggregation of the PS NP-NH2, whereas, for the PS MPs, no conclusive results were found, indicating that the surface charge plays an essential role in the MNP aggregation process. Moreover, to investigate the toxicological potential of MNPs, a mussel species (M. galloprovincialis) was exposed to different concentrations of MPs and NPs, separately, with and without the technology. In this context, mussels were sampled after 7, 14, and 21 days of exposure, and the gills and digestive glands were collected for analysis of oxidative stress biomarkers and histological observations. In general, the results indicate that MNPs trigger the production of reactive oxygen species (ROS) in mussels and induce oxidative stress, making gills the most affected organ. Yet, when the technology was applied in moderate concentrations, NPs showed adverse effects in mussels. The histological analysis showed no evidence of MNPs in the gill's tissues. [ABSTRACT FROM AUTHOR]

Simple Summary: Exploring the interactions between organophosphorus flame retardants (OPFRs), microplastics, and freshwater organisms is essential for comprehending the dynamics within freshwater ecosystems to anticipate the potential impacts of organic pollutants and plastic particles. To address this need, the current study examined the exposure effects of 10 mg L−1 of flame-retardant aluminium diethylphosphinate (ALPI), 10 μg mg−1liver of microplastics polyurethane (PU), and their combination on the freshwater planarian Girardia tigrina. Twenty-four-hour exposure of G. tigrina to both ALPI and PU resulted in a sequential effect reflected in a significant reduction in locomotor activity, i.e., exposure may involve a combination of direct neurotoxic effects and the indirect energetic costs associated with the adaptive responses to mitigate the adverse effects. Other biochemical responses, e.g., oxidative stress and metabolic responses, remained unaffected compared to control. Incorporating behavioural indicators into toxicological assays enhances the predictive power of these assessments, enabling a more accurate evaluation of the ecological consequences of pollutant exposure. This integrated approach not only improves our understanding of the complex interactions between organisms and their environment, but also informs more effective strategies for mitigating the detrimental effects of mixtures of pollutants on freshwater ecosystems. Understanding the interplay among organophosphorus flame retardants (OPFRs), microplastics, and freshwater organisms is crucial for unravelling the dynamics within freshwater environments and foreseeing the potential impacts of organic pollutants and plastic contamination. For that purpose, the present research assessed the exposure impact of 10 mg L−1 flame-retardant aluminium diethylphosphinate (ALPI), 10 μg mg−1liver microplastics polyurethane (PU), and the combination of ALPI and PU on the freshwater planarian Girardia tigrina. The exposure to both ALPI and PU revealed a sequential effect, i.e., a decrease in locomotor activity, while oxidative stress biomarkers (total glutathione, catalase, glutathione S-transferase, lipid peroxidation) and metabolic responses (cholinesterase activity, electron transport system, and lactate dehydrogenase) remained unaffected. Despite this fact, it was possible to observe that the range of physiological responses in exposed organisms varied, in particular in the cases of the electron transport system, cholinesterase activity, glutathione S-transferase, catalase, and levels of total glutathione and proteins, showing that the energetic costs for detoxification and antioxidant capacity might be causing a lesser amount of energy allocated for the planarian activity. By examining the physiological, behavioural, and ecological responses of planarians to these pollutants, insights can be gained into broader ecosystem-level effects and inform strategies for mitigating environmental risks associated with OPFRs and microplastic pollution in freshwater environments. [ABSTRACT FROM AUTHOR]

Hydroponic experiments were conducted to investigate the effects of varying particle sizes (5 μm, 0.1 μm, and 0.08 μm) and concentrations (0, 50, 100, 200, 500, 1000, and 2000 mg/L) of polystyrene plastic microspheres (PS-MPs) on the germination and growth of P. sativum seeds in order to investigate the effects of the microplastic environment on crop seed germination and seedling growth. The findings demonstrated that PS-MPs significantly harmed P. sativum seed germination. Specifically, low concentrations or high particle sizes weakened or promoted P. sativum seed germination, indicating varying susceptibilities to PS-MP treatment at different particle sizes. The strongest inhibitory effect on growth was observed under small particle size (0.08 μm) and high concentration (2000 mg/L). Stress had less of an impact on P. sativum in environments with low concentrations of PS-MPs, but in environments with medium and high concentrations, physiological and biochemical indicators like germination rate, stem length, and root length were significantly impacted. Furthermore, the particle size and concentration of PS-MPs had an impact on the growth effect of P. sativum seedlings. The indices of P. sativum seed germination were significantly impacted by the particle size of PS-MPs, despite the fact that PS-MP concentration was low. When the concentration of PS-MPs is low, the effects of varying PS-MP particle sizes on seed germination and root length are as follows: 0.1 μm > 5 μm > 0.08 μm. The concentration of PS-MPs had a significant impact on how it affected the buildup of dry matter and photosynthetic pigment. [ABSTRACT FROM AUTHOR]

The aquatic environment encompasses a wide variety of pollutants, from plastics to drug residues, pesticides, food compounds, and other food by-products, and improper disposal of waste is the main cause of the accumulation of toxic substances in water. Monitoring, assessing, and attempting to control the effects of contaminants in the aquatic environment are necessary and essential to protect the environment and thus human and animal health, and the study of aquatic ecotoxicology has become topical. In this respect, zebrafish are used as model organisms to study the bioaccumulation, toxicity, and influence of environmental pollutants due to their structural, functional, and material advantages. There are many similarities between the metabolism and physiological structures of zebrafish and humans, and the nervous system structure, blood–brain barrier function, and social behavior of zebrafish are characteristics that make them an ideal animal model for studying neurotoxicity. The aim of the study was to highlight the neurotoxicity of nanoplastics, microplastics, fipronil, deltamethrin, and rotenone and to highlight the main behavioral, histological, and oxidative status changes produced in zebrafish exposed to them. [ABSTRACT FROM AUTHOR]

The aim of the study is to investigate the leaching of fluorescent dissolved organic matter (fDOM) from microplastics. In addition, this study identifies the connection between fDOM and microplastics in the aquatic environment. Three‐dimensional excitation–emission matrix identified five fluorophores, that is, peak A, M, T, Tuv, and Wuv, and the parallel factor analysis modeling identified five components, that is, tryptophan‐like, p‐hydroxy acetophenone, humic acid (C‐like), detergent‐like, and fulvic acid (M‐like) in the urban surface water. Mimic experiments using commonly used synthetic plastic (like microplastics) in Mili‐Q water under solar radiation and dark environments demonstrate the release of fDOM from plastic. Two fluorophore peaks were observed at Ex/Em = 250/302 nm and Ex/Em = 260/333 nm for the expanded polystyrene plastic polymer and one fluorophore peak at Ex/Em = 260/333 nm for the low‐density polyethylene. Fluorophore and component intensity exhibited notable associations with microplastics in the aquatic environment. These findings indicated that the characteristics and dynamics of fDOM in urban surface water are influenced by microplastics. Practitioner Points: Fluorescent dissolved organic matters were identified in urban surface waters.Expanded polystyrene (EPS) had shown two fluorophores at Em/Ex = 250/302 and Em/Ex = 260/333.Low‐density polyethylene (LDPE) had one fluorophore at Em/Ex = 260/333.Fluorophore and component intensity in the aquatic settings exhibited associations with microplastics. [ABSTRACT FROM AUTHOR]

The escalating issue of microplastic (MP) pollution poses a significant threat to the marine environment due to increasing plastic production and improper waste management. The current investigation was aimed at quantifying the MP concentration on 25 beaches on the Maharashtra coast, India. Beach sediments (1 kg) were collected from each site, with five replicates to evaluate the extent of MPs. The samples were homogenized, and three 20 g replicas were prepared for subsequent analysis. Later, the samples were sieved, and MPs were extracted using previously published protocols. The abundance of MPs found as 1.56 ± 0.79 MPs/g, ranges from 0.43 ± 0.07 to 3 ± 0.37 MPs/g. Fibers were found as the most abundant shape of MPs. Size‐wise classification revealed dominance of <1 mm and 1–2 mm‐sized MPs. Blue‐ and black‐colored MPs were recorded dominantly. Polymer identification of MPs revealed polyurethane, polypropylene, polyvinyl chloride, acrylic or polymethyl methacrylate, and rubber. The findings revealed that MPs were found to be higher at highly impacted sites, followed by moderately impacted sites and low‐impacted sites, possibly due to a different degree of anthropogenic pressure. The study recommended the urgent need for effective policy to prevent plastics accumulation in the coastal environment of Maharashtra State, India. Practitioner Points: The study investigated the abundance and distribution of microplastics in the marine environment, specifically in sediments.The most common type of microplastic found was fibers, followed by fragments and films.Microplastics were found to pose a potential risk to the marine ecosystem, although further research is needed to fully understand their ecological impact.Future research should focus on expanding the sample size, assessing long‐term effects, exploring sources and pathways, and considering size and shape of microplastics.The findings recommended urgent action to mitigate plastic pollution in Maharashtra coast. [ABSTRACT FROM AUTHOR]

The impact of microplastics (MPs) on the metabolic functions of the liver is currently unclear and not completely understood. To investigate the effects of the administration of MPs on the hepatic metabolism of normal and obese mice, alterations in the lipid, glucose (Glu), and amino acid regulation pathways were analyzed in the liver and adipose tissues of C57BL/6Korl (wild type, WT) or C57BL/6-Lepem1hwl/Korl mice (leptin knockout, Lep KO) orally administered polystyrene (PS) MPs for 9 weeks. Significant alterations in the lipid accumulation, adipogenesis, lipogenesis, and lipolysis pathways were detected in the liver tissue of MP-treated WT and Lep KO mice compared to the vehicle-treated group. These alterations in their liver tissues were accompanied by an upregulation of the serum lipid profile, as well as alterations in the adipogenesis, lipogenesis, and lipolysis pathways in the adipose tissues of MP-treated WT and Lep KO mice. Specifically, the level of leptin was increased in the adipose tissues of MP-treated WT mice without any change in their food intake. Also, MP-induced disruptions in the glycogenolysis, Glu transporter type 4 (GLUT4)-5′ AMP-activated protein kinase (AMPK) signaling pathway, levels of lipid intermediates, and the insulin resistance of the liver tissues of WT and Lep KO mice were observed. Furthermore, the levels of seven endogenous metabolites were remarkably changed in the serum of WT and Lep KO mice after MP administrations. Finally, the impact of the MP administration observed in both types of mice was further verified in differentiated 3T3-L1 adipocytes and HepG2 cells. Thus, these results suggest that the oral administration of MPs for 9 weeks may be associated with the disruption of lipid, Glu, and amino acid metabolism in the liver tissue of obese WT and Lep KO mice. [ABSTRACT FROM AUTHOR]

This study reports an innovative approach for producing nanoplastics (NP) from various types of domestic waste plastics without the use of chemicals. The plastic materials used included water bottles, styrofoam plates, milk bottles, centrifuge tubes, to-go food boxes, and plastic bags, comprising polyethylene terephthalate (PET), polystyrene (PS), polypropylene (PP), high-density polyethylene (HDPE), and Poly (Ethylene-co-Methacrylic Acid) (PEMA). The chemical composition of these plastics was confirmed using Raman and FTIR spectroscopy, and they were found to have irregular shapes. The resulting NP particles ranged from 50 to 400 nm in size and demonstrated relative stability when suspended in water. To assess their impact, the study investigated the effects of these NP particulates on cell viability and the expression of genes involved in inflammation and oxidative stress using a macrophage cell line. The findings revealed that all types of NP reduced cell viability in a concentration-dependent manner. Notably, PS, HDPE, and PP induced significant reductions in cell viability at lower concentrations, compared to PEMA and PET. Moreover, exposure to NP led to differential alterations in the expression of inflammatory genes in the macrophage cell line. Overall, this study presents a viable method for producing NP from waste materials that closely resemble real-world NP. Furthermore, the toxicity studies demonstrated distinct cellular responses based on the composition of the NP, shedding light on the potential environmental and health impacts of these particles. [ABSTRACT FROM AUTHOR]

Aquatic ecosystems serve as the primary reservoir for microplastics entering the environment. The assessment of the microplastics content in natural waters and sediments is a pressing task, the resolution of which is essential for evaluating the degree of pollution of water bodies, identifying sources of contamination, and assessing potential risks to aquatic inhabitants. Currently, there is no universal analytical approach to separating microplastics from natural waters and sediments for subsequent identification. This review summarizes information on the methods for sampling microplastics from natural waters and sediments and sample preparation techniques, including size- and density-based particle separation methods, as well as digestion-based methods relying on the digestion of samples to remove natural organic matter. Additionally, it outlines the classification of microplastics and provides general insights into their prevalence in aquatic ecosystems and potential toxicity. [ABSTRACT FROM AUTHOR]

Plastic has become very popular in recent years due to its durability and properties. Despite its many advantages, humanity has developed a certain dependence on this material, which represents an increase in its use and in turn, in waste. One of the most widely used plastic polymers is the polystyrene (PS), as is used in a wide range of applications due to its low cost and easy production, although after the useful life of the plastic, it is considered as waste. When plastic is exposure to atmospheric conditions such as UV radiation, it degrades and fragments giving rise to microplastics (MPs), which are defined as small particles that do not exceed 5 mm, representing a threat to the environment because when they degrade the properties decay, a dimensional change is generated and they can also be easily transported not only to the environment but also to organisms. This review article focuses on highlighting the main pathways that MPs follow when interacting with humans and the potential effects of PS-MPs on the cytoskeleton, as well as highlighting the need for more studies in this regard. [ABSTRACT FROM AUTHOR]

The topic of riverine microplastics is of great interest to the general public, yet the univocal scientific knowledge on this topic is limited. This review investigated the occurrence of microplastics in 6 major European rivers and their tributaries based on the results from 29 studies. We examined the reviewed studies in regard to data quality and reproducibility and assessed the abundance of microplastics in different sections of the water column. Furthermore, we investigated the chemical composition and potential origin of the reported riverine microplastics. We found that polystyrene, polypropylene, and polyethylene were the most abundant polymer types. The majority of primary microplastics arose from the industry sector as well as from personal care and cleaning products, whereas secondary microplastics constituted fibers from synthetic textiles and fragments of diverse origins. We highlighted the diversity of experimental and analytical approaches that could lead to high uncertainties in the measurements of microplastics abundance. Furthermore, the presence of microplastics in rivers was found to vary spatially likely due to point and nonpoint pollution sources of anthropogenic activities. Heterogenous environmental processes impacted the fate of microplastics characterized by various forms, sizes, and densities, in different ways. This impeded the identification of representative quantitative measurements of microplastics across different time frames. We advocate for the development of standardized protocols by the research community to ensure higher reproducibility of sampling, processing, and analysis of microplastics in aquatic environments. We recommend long‐term and site‐specific monitoring on microplastics with high data comparability to better inform policy making. This article is categorized under:Science of Water > Water QualityWater and Life > Conservation, Management, and Awareness [ABSTRACT FROM AUTHOR]

Raman images were constructed for polypropylene (PP) films before and after ultraviolet (UV) irradiation (100 mW, 248–436 nm) for 10 h using several intensity ratios of Raman bands that are sensitive to crystallization of PP. In the images of PP films before the irradiation the intensity ratios are nearly uniform for the films but for those of the PP films after the irradiation, the ratios become large with a mottled pattern, indicating that recrystallization occurs in the PP films upon the irradiation of the UV light. The UV-irradiated PP films show worm-like shaped structures in few micrometer order representing the recrystallization of PP. The temperature gradient of PP is low (273 K), and thus, it is very likely that due to UV energy and polymer fragmentation, PP molecules become more mobile and some parts of molecular chains in amorphous parts of PP molecules lead to their rearrangement and recrystallization. In this study, we demonstrate that Raman imaging clearly detects subtle changes in the crystallinity with a micrometer order structure which morphological images cannot observe. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution has become a health concern subject in recent years. Althoughann increasing number of studies about the ingestion of microplastics by fish, research on the oxidative stress response to MPs in natural environments is quite limited. In this study, the identification and characterization of MPs in gill (G), muscle tissues (M), and gastrointestinal tract (GI) of turbot (Scophthalmus maximus) were evaluated. Oxidative damage of MPs on the brain (B), liver (L), gill (G), and muscle (M) tissues as well as their effect on superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), paraoxonase (PON), arylesterase (AR) myeloperoxidase (MPO), and malondialdehyde (MDA) biomarkers were evaluated. The potential transmission of MPs from muscle tissues to humans was examined. Results showed that gills contain the highest amounts of MPs, ethylene propylene is the most dominant polymer type, black and blue are the most common MP color, fiber is the most common shape, and 50-200 µm is the most common MP size. Results showed that MPs cause oxidative stress of tissues with inhibiting effect on enzyme activities and promoting impact on lipid peroxidation. The oxidative damage mostly affected the liver (detoxification organ) followed by gill tissue. The intake of MPS in the European Union was estimated by EFSA as 119 items/year, while in Turkey it is 47.88 items/year. This study shows that more research is needed in terms of ecosystem health and food chain safety. The risk assessment of MPs in living organisms and environmental matrices including food safety and human health should be considered a public health issue. [ABSTRACT FROM AUTHOR]

Due to low degradability of plastic materials, high usage, and low cost, microplastics (MPs) is becoming ubiquitous environmental pollutant. Wastewater treatment plants (WWTP) are one of main sources, where most of the MPs from wastewaters ends in waste sludge. Anaerobic digestion is one of most promised techniques of waste sludge management. The aim of this paper was to evaluate the impact of polyethylene terephthalate (PET) and polypropylene (PP) microplastics in the waste sludge with and without ozonation as possible pretreatment, on biogas and methane production with OxiTop® method. In the first set of experiments, PET inhibited (up to 6% at 0.1 g L−1) or promoted (up to 3% at 1 g L−1) methane production but increased cumulative biogas production (up to 38% at 0.5 g L−1). PP inhibited methane production (up to 5% at 0.5 g L−1) but its impact on biogas production was dependent upon concentration of MPs added. In the second set of experiments, pretreatment of non-contaminated waste sludge by ozonation (3.54 gozone h−1) inhibited methane yield. Longer time of ozonation of PP-contaminated waste sludge reduced inhibition of methane yield, while in the case of PET-contaminated waste sludge, it was increased. [ABSTRACT FROM AUTHOR]

The exponential increase in global plastic usage has led to the emergence of nano- and microplastic (NMP) pollution as a pressing environmental issue due to its implications for human and other mammalian health. We have developed methodologies to extract solid materials from human tissue samples by saponification and ultracentrifugation, allowing for highly specific and quantitative analysis of plastics by pyrolysis-gas chromatography and mass spectrometry (Py-GC-MS). As a benchmark, placenta tissue samples were analyzed using fluorescence microscopy and automated particle count, which demonstrated the presence of >1-micron particles and fibers, but not nano-sized plastic particles. Analyses of the samples (n  = 10) using attenuated total reflectance-Fourier transform infrared spectroscopy indicated presence of rayon, polystyrene, polyethylene, and unclassified plastic particles. By contrast, among 62 placenta samples, Py-GC-MS revealed that microplastics were present in all participants' placentae, with concentrations ranging widely from 6.5 to 685 µg NMPs per gram of placental tissue, averaging 126.8 ± 147.5 µg/g (mean±SD). Polyethylene was the most prevalent polymer, accounting for 54% of total NMPs and consistently found in nearly all samples (mean 68.8 ± 93.2 µg/g placenta). Polyvinyl chloride and nylon each represented approximately 10% of the NMPs by weight, with the remaining 26% of the composition represented by 9 other polymers. Together, these data demonstrate advancements in the unbiased quantitative resolution of Py-GC-MS applied to the identification and quantification of NMP species at the maternal-fetal interface. This method, paired with clinical metadata, will be pivotal to evaluating potential impacts of NMPs on adverse pregnancy outcomes. [ABSTRACT FROM AUTHOR]

Anthropogenically modified microparticles including microplastics are present in municipal wastewater treatment plant (WWTP) effluents; however, it is unclear whether biotic exposures are elevated downstream of these outfalls. In the fall of 2019, the present study examined whether microparticle levels in resident fish, environmental samples, and caged organisms were elevated near the Waterloo and Kitchener WWTP outfalls along the Grand River, Ontario, Canada. Wild rainbow darters (Etheostoma caeruleum) were collected from a total of 10 sites upstream and downstream of both WWTPs, along with surface water and sediment samples to assess spatial patterns over an approximately 70‐km river stretch. Amphipods (Hyalella azteca), fluted‐shell mussels (Lasmigona costata), and rainbow trout (Oncorhynchus mykiss) were also caged upstream and downstream of one WWTP for 14 or 28 days. Whole amphipods, fish digestive tracts, and mussel tissues (hemolymph, digestive glands, gills) were digested with potassium hydroxide, whereas environmental samples were processed using filtration and density separation. Visual identification, measurement, and chemical confirmation (subset only) of microparticles were completed. Elevated abiotic microparticles were found at several upstream reference sites as well as at one or both wastewater‐impacted sites. Microparticles in amphipods, all mussel tissues, and wild fish did not show patterns indicative of increased exposures downstream of effluent discharges. In contrast, elevated microparticle counts were found in trout caged directly downstream of the outfall. Across all samples, cellulose fibers (mainly blue and clear colors) were the most common. Overall, results suggest little influence of WWTP effluents on microparticles in biota but rather a ubiquitous presence across most sites that indicates the importance of other point and nonpoint sources to this system. Environ Toxicol Chem 2024;43:1047–1061. © 2024 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada. [ABSTRACT FROM AUTHOR]

Microplastic contamination is ubiquitous across the globe, even in remote locations. Still, the sources and pathways of microplastics to such locations are largely unknown. To investigate microplastic contamination in a semi‐remote location, we measured microplastic concentrations in nine oligotrophic lakes within and around the International Institute for Sustainable Development—Experimental Lakes Area in northwestern Ontario, Canada. Our first objective was to establish ambient concentrations of microplastics in bottom sediments, surface water, and atmospheric deposition in semi‐remote boreal lakes. Across all lakes, mean shallow and deep sediment microplastic concentrations, near‐surface water microplastic concentrations from in situ filtering, and dry atmospheric microplastic deposition rates were 551 ± 354 particles kg−1, 177 ± 103 particles kg−1, 0.2 ± 0.3 particles L−1, and 0.4 ± 0.2 particles m−2 day−1, respectively. Our second objective was to investigate whether microplastic contamination of these lakes is driven by point sources including local runoff and direct anthropogenic inputs or nonpoint sources such as atmospheric deposition. Lakes were selected based on three levels of anthropogenic activity—low, medium, and high—though activity levels were minimal across all study lakes compared with highly populated areas. Whereas a positive correlation would indicate that point sources were a likely pathway, we observed no relationship between the level of anthropogenic activity and microplastic contamination of surface water. Moreover, the composition of microplastics in surface water and atmospheric deposition were similar, comprising mostly polyester and acrylic fibers. Together, these results suggest that atmospheric deposition may be the main pathway of microplastics to these remote boreal lakes. Environ Toxicol Chem 2024;43:999–1011. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Plastics are extensively utilized across various industries due to their affordability, chemical stability, insulation properties, durability, and resistance to water. Nowadays, plastics have become an integral part of modern society, while microplastics (MPs) and nanoplastics (NPs) are rapidly accumulating in soil, which could have detrimental effects on both ecosystems and human health. This review first analyzes the latest literature on MPs, soil and plant, and analyzes the future research trends. The review encompasses the latest findings on the effects of MPs and NPs on higher plants, elucidating the mechanisms of MPs and NPs absorption by plants from the soil and their resulting phytotoxicity. Furthermore, the review underscores the imperative for further investigations aimed at comprehending the long-term repercussions of MPs and NPs on plant growth, physiology, reproduction, and their potential entry into the food chain. Notably, NPs exhibit a unique propensity to translocate via the xylem to various plant organs, including seeds, raising concerns for human health, given their heightened uptake by plant roots compared to MPs. In addition, the impacts of MPs and NPs in conjunction with other environmental contaminants might be amplified. Finally, important concerns and potential future research initiatives in the area are considered. The authors call for urgent action to address the problem of plastic pollution and suggest that a multi-disciplinary approach is needed to find solutions to this global problem. [ABSTRACT FROM AUTHOR]

The adsorption characteristics between extracellular polymeric substances (EPS) and microplastics polystyrene (PS) in anaerobic granular sludge were studied. In anaerobic granular sludge, the smaller the particle size of microplastics, the more obvious the increase of total EPS. 0.5 um PS promotes an increase in EPS to 1.14 times that of the blank reactor, 200 um PS reduces the EPS to 0.91 times. Among the five fractions of EPS, the hydrophilic fraction (HPI) fraction can resist the toxicity of small size microplastics, so the increment is the most obvious. 5 um PS promotes an increase in the relative intensity of HPI from 55.5 mg/gVS to 87.2 mg/gVS. The adsorption behavior of the five fractions of EPS on microplastics PS can be well described by pseudo-second-order kinetics model and Freundlich model. Hydrophobic interaction, π-π electron-donor-receptor interaction, chemical adsorption and electrostatic attraction simultaneously affect the adsorption of five fractions of EPS by PS. The analysis of infrared spectroscopy, which showed that O-H stretching vibration, carbonyl C-O group, amide-1, amide-2 absorptivity, and phenol C-O bond have a great contribution to the adsorption of microplastics. It can be seen that small particle sizes of PS have a more significant impact on sludge EPS. [ABSTRACT FROM AUTHOR]

In the current study to investigate the characte – rization of Microplastic – released into the Qara-Sou river, Kermanshah, Iran, 12 sampling sites were surveyed along a 100 km stretch of the river. The maximum and minimum numbers of MPs were about 10,000 and 45,000 items per m3. The average concentration of MPs in the Qara-sou river was 23,666 ± 12147 items per m3. The dominant size and shape of MPs ranged from 0.025 to 1 mm (~44%) and fiber shapes (~78%). In addition, SEM-EDS analyses confirmed the presence of carbon-dominant peaks with O, Ca, Fe, Al, and Si. FTIR spectra have identified some MPs in the PVC, PU, PS, PE, and nylon polymer categories. A high level of MPs was discharged into the Qara-sou river, which should be attracting the attention of the community and decision-makers to reduce damage to the environment and human health. [ABSTRACT FROM AUTHOR]

Plastic waste pollution is one of the biggest problems in the world today. The amount of plastic in the environment continues to increase, and human exposure to microplastic (MP) has become a reality. This subject has attracted the attention of the whole world. The MP problem has also been noticed by the scientific community. The term microplastic is mostly used to define synthetic material with a high polymer content that can have a size range from 0.1 to 5000 µm. This paper aims to characterize the routes of exposure to MP, define its pollution sources, and identify food types contaminated with plastics. This review addresses the current state of knowledge on this type of particles, with particular emphasis on their influence on human health. Adverse effects of MP depend on routes and sources of exposure. The most common route of exposure is believed to be the gastrointestinal tract. Sources of MP include fish, shellfish, water as well as tea, beer, wine, energy drinks, soft drinks, milk, salt, sugar, honey, poultry meat, fruits, and vegetables. Studies have shown that particles of PET, PE, PP, PS, PVC, PA, and PC are the most frequently found in food. [ABSTRACT FROM AUTHOR]

The widespread production and use of plastics have resulted in accumulation of plastic debris in the environment, gradually breaking down into smaller particles over time. Nano-plastics (NPs) and microplastics (MPs), defined as particles smaller than 100 nanometers and 5 millimeters, respectively, raise concerns due to their ability to enter the human body through various pathways including ingestion, inhalation, and skin contact. Various investigators demonstrated that these particles may produce physical and chemical damage to human cells, tissues, and organs, disrupting cellular processes, triggering inflammation and oxidative stress, and impacting hormone and neurotransmitter balance. In addition, micro- and nano-plastics (MNPLs) may carry toxic chemicals and pathogens, exacerbating adverse effects on human health. The magnitude and nature of these effects are not yet fully understood, requiring further research for a comprehensive risk assessment. Nevertheless, evidence available suggests that accumulation of these particles in the environment and potential human uptake are causes for concern. Urgent measures to reduce plastic pollution and limit human exposure to MNPLs are necessary to safeguard human health and the environment. In this review, current knowledge regarding the influence of MNPLs on human health is summarized, including toxicity mechanisms, exposure pathways, and health outcomes across multiple organs. The critical need for additional research is also emphasized to comprehensively assess potential risks posed by degradation of MNPLs on human health and inform strategies for addressing this emerging environmental health challenge. Finally, new research directions are proposed including evaluation of gene regulation associated with MNPLs exposure. [ABSTRACT FROM AUTHOR]

Exposure to microplastics may be associated with damage of immune system. Polypropylene microplastics (PP-MPs) with a wide range of beneficial applications have not been extensively studied with respect to the immune system. The aim of this investigation is to examine the influence of two different sizes of PP-MPs (5.2 and 23.9 μm diameter) on immune system components in ICR mice. PP-MPs were administered orally to female and male mice at 0 (corn oil vehicle), 500, 1000, or 2000 mg/kg/d for single and daily for 4-week repeated toxicity test, respectively. No significant differences were observed in number of thymic CD4+, CD8+, CD4+CD8+ T lymphocytes, splenic helper T cells, cytotoxic T cells, and B cells. The ratio of interferon-γ to interleukin-4 in culture supernatants from activated splenocytes ex vivo (48 hr) was lower in females which were repeatedly administered with PP-MPs compared to vehicle irrespective of PP-MPs size and dose. In contrast, the opposite trend was observed in males. Production of tumor necrosis factor-α was upregulated in females that were repeatedly exposed to PP-MPs. The serum IgG2a/IgG1 ratio was lowered in female receiving large-size PP-MPs. Data suggest that immune disturbances resulting in predominant type-2 helper T cell reactivity may occur in mice, especially in females, when repeatedly exposed to PP-MPs. Further investigations with longer exposure periods are necessary to determine the immunotoxicities attributed to PP-MPs. [ABSTRACT FROM AUTHOR]

Investigating the presence of microplastics in the Pasig River, the highest plastic-emitting river in the Philippines and one of the ocean's leading contributors of these materials, is highly relevant. In this study, surficial sediments in eight stations along the main channel of the Pasig River were analyzed for microplastic content, heavy metals, and soil texture. The microplastics were categorized according to shape, color, and size. The polymer type was determined using infrared spectroscopy. The number of microplastics was correlated with heavy metals, soil texture, and flow velocity. The results show that the dominant shape, color, size, and polymer type were fragment, color white, size range from 0 to 500 μm, and polyvinyl alcohol, respectively. Downstream stations 5 and 8 had the highest microplastic concentration. The number of microplastics showed a positive moderate correlation with percent sand (r = 0.40) and clay (r = 0.42), and a negative high correlation with percent silt (r=-0.80). For microplastics and heavy metals, a positive moderate correlation was observed for iron (r = 0.52) and zinc (r = 0.58), while a negative weak correlation was present for lead (r=-0.06). Microplastics and flow velocity showed weak correlations demonstrating that the accumulation in the bottom river sediment may be based on the proximity of the plastic source rather than on the flowing water with plastic sources. Results reflect the diverse influences on the Pasig River which is surrounded by informal settlements, manufacturing industries, urban offices, and residential areas. More plastic management initiatives and better implementation of existing laws should be done by the government. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrophobic ZIF-8/SA monolithic materials were fabricated via in situ synthesis. • The cooperation of SA, PDMS, and ZIF-8 significantly enhanced adsorption capacity. • The composites displayed rapid kinetic adsorption. • The composites have remarkable absorption recyclability. Microplastics (MPs), a newly emerging class of environmental contaminants, pose a severe threat to the entire ecosystem. The development of efficient and environmentally responsible adsorbents for removing the MPs is a particularly urgent research. Herein, a kind of monolithic ZIF-8 based adsorbents featuring stable hydrophobicity and micropore-mesopore-macropore hierarchical porous structure were fabricated by in situ growth of ZIF-8 nanoparticles on sodium alginate (SA) framework, and using polydimethylsiloxane (PDMS) as a hydrophobic agent. The monolithic nature of ZIF-8/SA allowed an easy solid–liquid separation process for adsorbents from water environment compared to powdered materials. The hierarchical porous structure ensures a remarkable MPs removal performance. The ZIF-8/SA showed high adsorption capacities of 594, 585, and 282 mg/g for polymethyl methacrylate (PMMA), poly (vinylidene difluoride) (PVDF), and polyvinyl chloride (PVC) respectively, and rapid adsorption kinetic progress within 120 min. The ZIF-8/SA adsorbents also exhibited excellent stability in the presence of interfering ions, acid/alkali, and humic acid, and displayed adsorption performance of > 70 % even in actual aquatic environment such as tap water, river water, and seawater. The results of characterizations showed that the synergistic effect of electrostatic interaction, hydrogen bonding, hydrophobic force, and van der Waals force was the main adsorption mechanism. The well-designed hydrophobic ZIF-8/SA monolithic materials would be promising to rapidly remove the MPs from the water environment. [ABSTRACT FROM AUTHOR]

Microplastic pollution has become one of the most concerned focuses in the world. Among many treatment methods, photocatalysis is considered to be one of the most environmentally friendly methods. In this work, the photodegradation behavior of polyamide microplastics is studied by using polyamide 6 PA6) as model microplastics and FeCl 3 as catalyst. It is hoped that the PA6 fiber can be effectively degraded by utilizing the strong oxidizing active species that can be produced after FeCl 3 is irradiated in water. The results shows that PA6 fiber can be almost completely degraded after 10 days of irradiation in FeCl 3 aqueous solution, indicating that it is promising to use this new method to solve the problem of PA6 type microplastics. In addition, the chain scission mechanism and degradation process of PA6 are analyzed in detail by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS), which provides a new insight for the study of polymer degradation mechanism. [Display omitted] [ABSTRACT FROM AUTHOR]