Microplastic Exposure Research Articles

Effects of Microplastic Exposure on Human Digestive, Reproductive, and Respiratory Health: A Rapid Systematic Review.

Microplastics are ubiquitous environmental contaminants for which there are documented human exposures, but there is a paucity of research evaluating their impacts on human health. We conducted a rapid systematic review using the "Navigation Guide" systematic review method. We searched four databases in July 2022 and April 2024 with no restriction on the date. We included studies using predefined eligibility criteria that quantitatively examined the association of microplastic exposure with any health outcomes. We amended the eligibility criteria after screening studies and prioritized digestive, reproductive, and respiratory outcomes for further evaluation. We included three human observational studies examining reproductive (n = 2) and respiratory (n = 1) outcomes and 28 animal studies examining reproductive (n = 11), respiratory (n = 7), and digestive (n = 10) outcomes. For reproductive outcomes (sperm quality) and digestive outcomes (immunosuppresion) we rated overall body evidence as "high" quality and concluded microplastic exposure is "suspected" to adversely impact them. For reproductive outcomes (female follicles and reproductive hormones), digestive outcomes (gross or microanatomic colon/small intestine effects, alters cell proliferation and cell death, and chronic inflammation), and respiratory outcomes (pulmonary function, lung injury, chronic inflammation, and oxidative stress) we rated the overall body of evidence as "moderate" quality and concluded microplastic exposure is "suspected" to adversely impact them. We concluded that exposure to microplastics is "unclassifiable" for birth outcomes and gestational age in humans on the basis of the "low" and "very low" quality of the evidence. We concluded that microplastics are "suspected" to harm human reproductive, digestive, and respiratory health, with a suggested link to colon and lung cancer. Future research on microplastics should investigate additional health outcomes impacted by microplastic exposure and identify strategies to reduce exposure.

Effects of polystyrene microplastics on the growth and metabolism of highland barley seedlings based on LC-MS

Microplastics are widely present in the environment and can adversely affect plants. In this paper, the effects of different concentrations of microplastics on physiological indices and metabolites of highland barley were investigated for the first time using a metabolomics approach, and revealed the response mechanism of barley seedlings to polystyrene microplastics (PS-MPs) was revealed. The results showed that the aboveground biomass of highland barley exposed to low (10 mg/L) and medium (50 mg/L) concentrations of PS-MPs increased by 32.2% and 48.2%, respectively. The root length also increased by 16.4% and 21.6%, respectively. However, the aboveground biomass of highland barley exposed to high (100 mg/L) concentrations of PS-MPs decreased by 34.8%, leaf length by 20.7%, and root length by 25.9%. Microplastic exposure increased the levels of antioxidant activity, suggesting that highland barley responds to microplastic stress through oxidative stress. Metabolome analysis revealed that the contents of 4 metabolites increased significantly with increasing PS-MPs concentration in positive ionmode, while the contents of 8 metabolites increased significantly with increasing PS-MPs concentration in negative ionmode (P < 0.05), including prunin, dactylorhin E, and schisantherin B. Additionally, PS-MPs significantly interfered with highland barley flavonoid biosynthesis, pyrimidine metabolism, purine metabolism, fatty acid biosynthesis, and phenylpropanoid biosynthesis metabolic pathways. This study provides a new theoretical basis for a deeper understanding of the effects of different concentrations of PS-MPs on highland barley.

Integrative Analysis of Pharmacology and Transcriptomics Predicts Resveratrol Will Ameliorate Microplastics-Induced Lung Damage by Targeting Ccl2 and Esr1

Background: Microplastics (MPs) are ubiquitous on earth, posing a growing threat to human health. Previous studies have shown that the lung is a primary organ for MPs exposure. Resveratrol (RES) is a common dietary polyphenol that exhibits anti-inflammatory and antioxidant effects. However, whether RES exerts a protective effect against MPs-induced lung damage is still unknown. Methods: The targets of RES were retrieved from five databases. Differentially expressed genes (DEGs) were identified through comprehensive bioinformatic analysis. Multiple algorithms were employed to screen for the core targets. Ultimately, molecular docking analysis and molecular dynamics (MD) simulations were utilized to confirm the binding affinity between RES and the core targets. Results: In total, 1235 DEGs were identified in the transcriptomes. After removing duplicates, a total of 739 RES targets were obtained from five databases, and 66 of these targets intersected with DEGs. The potential core targets (Esr1, Ccl2) were further identified through topological analysis and machine learning. These findings were subsequently verified by molecular docking and MD simulations. Conclusions: This study demonstrated that RES may mitigate lung injury induced by MPs by targeting Esr1 and Ccl2. Our research offers a novel perspective on the prevention and treatment of MPs-induced lung injury.

Research Progress for the Toxic Effects of Microplastics on Soil Animals and Plants

Terrestrial ecosystems represent the most direct and principal reservoirs of plastic contamination on Earth. The toxic effects of microplastic exposure on terrestrial plants have been analyzed from the perspectives of direct toxicity, indirect toxicity, and combined toxicity with other pollutants. By investigating the impacts on the growth, behavior, and oxidative stress responses of soil animals, the toxicological patterns of microplastics have been elucidated. Moreover, the primary factors influencing the toxicity of microplastics on both fauna and flora have been discussed based on current research. The results indicated that for the majority of terrestrial plants, microplastics could inhibit seed germination, adhere to root surfaces, enter the plant body and induce oxidative stress, inhibit photosynthesis, and cause cellular and genetic toxicity. Soil animals could ingest and accumulate microplastics to varying extents, resulting in toxic effects such as aberrant gene expression, oxidative stress, intestinal toxicity, and alterations of growth and behavior on the genetic, cellular, tissue, and individual levels. Furthermore, these effects were also linked to microplastic additives and the adsorbed pollutants. The impact of microplastics on terrestrial plants and animals at environmentally relevant concentrations cannot be overlooked, with particle size emerging as a critical factor influencing toxic effects. The findings provide a basis for assessing the ecological risks of microplastics in soil environments and offer insights into future research directions.

Microplastic particles in human blood and their association with coagulation markers

Recent studies have indicated potential health risks associated with microplastics (MPs) exposure, including alterations in blood coagulation homeostasis. This cross-sectional study aimed to quantitatively examine MPs in human blood and assess their association with coagulation markers. We recruited 36 healthy adults, collected whole blood samples, and analyzed MPs using Fourier-transform infrared (µ-FTIR) spectroscopy. Lifestyle factors related to MP exposure were assessed, such as the use of plastic food containers. Coagulation and inflammatory markers in blood samples were analyzed, including C-reactive protein, prothrombin time, activated partial prothrombin time (aPTT), antithrombin III, platelet count, erythrocyte sedimentation rate, and fibrinogen. MPs were detected in 88.9% of the participants, with a mean concentration of 4.2 MPs/mL. The predominant types of plastics identified were polystyrene and polypropylene. MPs were significantly higher in participants with a greater use of plastic food containers. A high MP load in the blood (≥ 3 MPs/mL) was significantly correlated with increased aPTT, C-reactive protein, and fibrinogen. We identified MPs in human blood, their association with specific lifestyle factors, and significant alterations in coagulation markers. This underscores the need for strategies to reduce human exposure to MPs, particularly in relation to blood coagulation and potential cardiovascular risks.

Polystyrene microplastics induce activation and cell death of neutrophils through strong adherence and engulfment

Ingested microplastics (MPs) can accumulate throughout whole body, which may induce the dysfunction of immune system. However, it remains unclear how MP exposure affects innate immune responses at the cellular level. We found that mouse neutrophils strongly bind and then engulf polystyrene MPs. This interaction leads to proinflammatory state of neutrophils and eventually results in apoptotic cell death through toll-like receptor signaling pathway in a bacteria-recognition mimetic manner. Moreover, our data verified that orally administered polystyrene MPs reach various organs in mice, where they are interacted with and endocytosed by neutrophils. We confirmed that human neutrophils also strongly bind and internalize polystyrene MPs. Additionally, RNA sequencing analysis of polystyrene MPs-exposed human neutrophils showed the upregulation of cell death-related function. Therefore, the accumulated MPs may exacerbate inflammatory immune response by disrupting neutrophil function. These results provide novel insight into the adverse responses of neutrophils induced by MP exposure.

Chronic exposure to polystyrene microplastics induces renal fibrosis via ferroptosis

With the increasing prevalence of microplastics (MPs) in the environment, human health has become a growing concern. After entering the human body, MPs accumulate in the kidneys, indicating that the kidneys are their major target organs. This study investigated nephrotoxicity associated with MPs, with a specific focus on polystyrene (PS) MPs and amino-functionalized polystyrene (PS-NH2) MPs. Although previous studies have documented the nephrotoxic effects associated with short-term exposure to MPs, the mechanisms of kidney toxicity caused by chronic long-term exposure to MPs remain largely unclear. In animal models, mice were exposed to MPs (10mg/L) at concentrations that are accessible to humans, administered via drinking water over a period of six months. These findings indicate that MPs can induce renal fibrosis by facilitating the onset of inflammation and accumulation of a substantial number of inflammatory cells. Our in vitro study showed that long-term exposure to MPs (60μg/mL) induced ferroptosis in renal tubular epithelial cells via ferritinophagy and secreted TGF-β1, leading to renal fibroblast activation. Conversely, the application of Fer-1, a ferroptosis inhibitor, prevents ferroptosis in renal epithelial cells and reverses the activation of renal fibroblasts. Our study identified a novel toxicity mechanism for renal fibrosis induced by MPs exposure, offering new insights into the detrimental effects of environmental MPs on human health.

Deciphering anammox response characteristics and potential mechanisms to polyethylene terephthalate microplastic exposure

Microplastics (MPs) are frequently detected in the wastewater. Herein, the short-term and long-term effects of polyethylene terephthalate (PET) MPs on anammox granular sludge were investigated and the potential response mechanisms were analyzed. Results showed that although short-term exposure of anammox granular sludge to PET-MPs induced a stress response, the nitrogen removal performance was not significantly affected. By contrast, long-term exposure to PET-MPs inhibited nitrogen removal performance with increased exposure time and PET-MP concentration. The total nitrogen removal efficiency (TNRE) decreased by 28.7% when sludge was exposed to 200mg/L of PET-MPs. However, the anammox activity recovered with prolonged operation time, and approximately 87% of the initial TNRE was recovered after three months. Microbial community evolution and metabolic exchange variations were the potential response mechanisms of anammox granular sludge to PET-MP exposure, with PET-MP exposure decreasing the anammox bacteria growth rate and relative symbiotic bacterial abundance in the anammox consortia and hindering cross-feeding pathways. The findings of this study provide novel insight into anammox behavior when treating wastewater containing PET-MPs.

Detection and quantification of microplastics in endometrial polyps and their role in polyp formation

With the increasing use of plastics, microplastic (MPs) pollution has garnered significant attention in recent years. Endometrial polyps are prevalent gynecological conditions in women of childbearing age, which impair endometrial receptivity and contribute to female infertility. However, no studies have yet reported the exposure of endometrial polyps to MPs. This study employed pyrolysis-gas chromatography/mass spectrometry and laser direct infrared spectroscopy to detect and compare MPs between normal endometrium and endometrial polyps. Using Py-GC/MS, we identified three main MPs in 14 normal endometrial samples and 16 endometrial polyps. The average abundance of MPs in the endometrial polyp group was significantly higher than in the normal endometrium group. The respective average abundance of polyethylene (PE), polystyrene (PS), and polyvinyl chloride (PVC) in the polyp and normal endometrium groups was 13.66 ± 2.0 vs. 7.132 ± 0.78 μg/g (p = 0.0009), 94.81 ± 10.67 vs. 69.29 ± 6.93 μg/g, and 67.67 ± 11.02 vs. 56.35 ± 6.90 μg/g. LDIR analysis revealed 13 different types of MPs, with polymethylmethacrylate being the most prevalent. Moreover, we discovered that PS microspheres can promote the proliferation and migration of endometrial stromal cells through PI3K/AKT pathway, which may be a key factor in the formation of endometrial polyps. This study is the first to explore the presence of MPs in endometrial polyps, compare the differences in MPs content between normal endometrium and endometrial polyps, and clarify the potential connection between MPs exposure and the formation of endometrial polyps. Further research is required to explore additional potential insights.

Microplastic effects on soil nitrogen cycling enzymes: A global meta-analysis of environmental and edaphic factors

Microplastic accumulation in soil ecosystems poses significant environmental concerns, potentially impacting nitrogen cycling processes and ecosystem health. This meta-analysis of 147 studies (1138 data points) assessed the impact of microplastics (MPs) on soil nitrogen-acquisition enzymes. We found that MPs exposure significantly increased soil urease (UE) and leucine aminopeptidase activities by 7.6 % and 8.0 %, respectively, while N-acetyl-β-D-glucosaminidase activity was not significantly affected. Biodegradable MPs showed more pronounced effects compared to conventional MPs. Enzyme activities were influenced by MPs properties (e.g., polymer type, size, concentration), experimental conditions (e.g., field or laboratory setting, temperature, nitrogen fertilization), and soil properties (e.g., clay content, pH, organic carbon, total nitrogen). For instance, acidic soils enhanced UE activity, while neutral soils reduced it. These findings emphasize the complex interactions between MPs and soil ecosystems, highlighting the need for context-specific environmental management strategies and policy-making approaches to mitigate the impacts of MPs pollution on soil health.

Resveratrol Butyrate Esters Reduce Hypertension in a Juvenile Rat Model of Chronic Kidney Disease Exacerbated by Microplastics

Background: Resveratrol is recognized as a promising nutraceutical with antihypertensive and prebiotic properties; however, its bioavailability in vivo is limited. To enhance its bioactivity, we developed resveratrol butyrate esters (RBEs). This study investigates whether RBEs can mitigate hypertension induced by chronic kidney disease (CKD) and exacerbated by microplastics (MPs) exposure in juvenile rats. Methods: Three-week-old male Sprague Dawley rats were fed either regular chow or 0.5% adenine chow for three weeks. The adenine-fed CKD rats (N = 8 per group) received either 5 μM MPs (10 mg/L) or MPs combined with RBE (25 mg/L) in their drinking water from weeks 3 to 9. Results: Our results indicate that MP exposure worsened CKD-induced hypertension, while RBE treatment resulted in a reduction in systolic BP by 15 mmHg (155 ± 2 mmHg vs. 140 ± 1 mmHg, p < 0.05). The combined exposure to adenine and MPs was associated with nitric oxide (NO) deficiency, which RBE treatment alleviated. Additionally, our findings revealed that RBE modulated both the classical and nonclassical renin–angiotensin system (RAS), contributing to its protective effects. We also observed changes in gut microbiota composition, increased butyric acid levels, and elevated renal GPR41 expression associated with RBE treatment. Conclusions: In conclusion, in this juvenile rat model of combined CKD and MP exposure, RBE demonstrates antihypertensive effects by modulating NO levels, the RAS, gut microbiota, and their metabolites.

Protective Effect of Resveratrol on Kidney Disease and Hypertension Against Microplastics Exposure in Male Juvenile Rats

Global pollution stems from the degradation of plastic waste, leading to the generation of microplastics (MPs). While environmental pollutants increase the risk of developing hypertension and kidney disease, the effects of MP exposure on these conditions in children remain unclear. Resveratrol, a phenolic compound known for its antihypertensive and renoprotective properties, has gained attention as a potential nutraceutical. This study investigates the effects of resveratrol on kidney disease and hypertension induced by MP exposure in a juvenile rat model. Three-week-old male Sprague–-Dawley (SD) rats were randomly allocated into four groups (n = 8 per group): a control group, a low-dose MP group (1 mg/L), a high-dose MP group (10 mg/L), and a high-dose MP group receiving resveratrol (50 mg/L). By 9 weeks of age, MP exposure resulted in elevated blood pressure and increased creatinine levels, both of which were mitigated by resveratrol treatment. The hypertension and kidney damage induced by high-dose MP exposure were linked to oxidative stress, which resveratrol effectively prevented. Additionally, resveratrol’s protective effects against hypertension and kidney damage were associated with increased acetic acid levels, reduced renal expression of Olfr78, and decreased expression of various components of the renin-angiotensin system (RAS). Low- and high-dose MP exposure, as well as resveratrol treatment, differentially influence gut microbiota composition. Our findings suggest that targeting oxidative stress, gut microbiota, and the RAS through resveratrol holds therapeutic potential for preventing kidney disease and hypertension associated with MP exposure. However, further research is needed to translate these results into clinical applications.

Exposure to polypropylene microplastics induces the upregulation of protein digestion-associated genes and microbiome reorganization in the octocoral Junceella squamata

Microplastics, a new type of pollutants found in coral reefs, have attracted increasing attention. However, most of the current research focuses on the scleractinian corals and few reports on Octocorallia. To reveal the impact of microplastic exposure on Octocorallia, we analyzed the transcriptional response of the coral hosts Junceella squamata along with changes to the diversity and community structure of its symbiotic bacteria following exposure to polystyrene microplastics. These results suggest that the microplastics have adverse impacts on nutrient metabolism and absorption in J. squamata. The symbiotic bacteria of J. squamata exhibited a clear response after exposure to microplastics, which may also reflect an adaptation mechanism of corals, and help to maintain the physiological function of coral symbiotic function under the exposure of microplastics. This study has revealed the impact of microplastic exposure on J. squamata, providing new insights for coral protection against the background of increased microplastics pollution.

Microplastics in stools and their influencing factors among young adults from three cities in China: A multicenter cross-sectional study

The mass concentration of microplastics in stools and influencing factors remain unclear. The aim was to investigate the types and mass concentrations of microplastics in the stools of young college students and to explore potential influencing factors. Twenty-six participants were recruited from colleges in each city using stratified simple sampling, including Changsha, Shanghai, and Changchun. Participants’ dietary and fluid intake behavior was recorded using the 3-day 24-h dietary questionnaire and the 7-day 24-h fluid intake record, respectively. Lifestyle factor information related to microplastic exposure was collected through a microplastic exposure questionnaire. Stools were collected and detected using pyrolysis gas chromatography–mass spectrometry (Py-GCMS) method. Eventually, 78 participants completed the study. The detection rate of microplastics, including polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), polypropylene (PP) and polyethylene terephthalate (PET), in stools was 98.7%, with a total mass concentration of 54.7 (10.1–102.7) μg/g. There were differences in the total mass concentrations of microplastics in the stools of participants in three cities, namely Changsha, Shanghai, and Changchun, which decreased sequentially (χ2 = 47.819, P < 0.05). Participants with a relatively high frequency of takeaway food consumption had higher total mass concentrations of microplastics mass concentrations in stools (χ2 = 7.390, P < 0.05). Participants with a relatively high frequency of consuming reheated food had a greater mass concentration of PET microplastics (χ2 = 6.117, P < 0.05). The total mass concentration of microplastics, as well as the mass concentrations of PE, PVC, PP, and PA66, in the bottled water intake group were greater than those in the nonintake group (all P < 0.05). Overall, the total mass concentration of microplastics in stools was related to residential city, consumption of reheated food, and bottled water intake (all P < 0.05). Young college students generally experience microplastic exposure, with the main types being PE, PVC, PS, PP, PET, and PA66. Living location, reheated food consumption, and bottled water intake were factors influencing microplastic exposure.

Polystyrene microplastics exposure: Disruption of intestinal barrier integrity and hepatic function in infant mice

The pervasive presence of microplastics (MPs) in infant formula and care products has emerged as a significant and underappreciated risk to public health. Notably, infants are at an elevated risk due to their underdeveloped intestinal defenses and liver detoxification capabilities, factors that could heighten their vulnerability to MPs. This study presents a comprehensive evaluation of the health implications linked to polystyrene microplastics (PSMPs) exposure during early life, examining both environmentally plausible and elevated levels. Based on histological analysis, in vivo imaging analysis, biochemical analysis and 16S rRNA sequencing results, our study found that oral PSMPs exposure in infant mice led to profound toxicological consequences, such as intestinal barrier impairment and hepatic injury, in a dose-dependent manner. Strikingly, even low ambient concentration of PSMPs (20 ppb) was sufficient to inflict considerable harm, disrupting the intestinal barrier, manifested that lessened mucus secretion, elevated iFABP level (276.50±10.73 pg/mL), decreased sIgA levels (0.60±0.03 mg/g), and pathological damage of intestinal tissues, allowing PSMPs accumulation and leakage into blood, inducing hepatotoxicity, such as increased TG levels (0.99±0.05 mmol/gprot) and lipid droplet accumulation. Furthermore, PSMPs exposure gives rise to aberrant bacterial colonization, dropping the abundance of probiotics as well as altering the abundance of pathogenic bacteria, which may contribute to the toxicity outcomes. The study underscores the critical need for vigilance regarding the insidious effects of PSMPs at environmental-relevant concentrations, especially in the context of infant exposure.

Different wetting states in riparian sediment ecosystems: Response to microplastics exposure

Climate change alters the wetting state of riparian sediments, impacting microbial community response and biogeochemical processes. Microplastics (MPs) invade nearly all ecosystems on earth, posing a significant environmental risk. However, little is known about the response mechanism of MP exposure in sediment ecosystems with different wetting states under alternating seasonal rain and drought conditions. In this study, sediments with three different wetting states were selected to explore the differential response of ecosystems to PLA MP exposure. We observed that PLA MP exposure directly affected biogeochemical processes in sediment ecosystems and induced significant changes in microbial communities. PLA MP exposure was found to alter the composition of key species and microbial functional groups in the ecosystem, resulting in a more complex, interconnected, but less stable microbial network. Our findings showed that PLA MP exposure enhances the contribution of stochastic processes, for example the dispersal limitation increasing from 7.41 % to 54.32 %, indicating that sediment ecosystems strive to buffer disturbances from PLA MP exposure. In addition, 87 pathogenic species were detected in our samples, with PLA MPs acting as vectors for their transmission, potentially amplifying ecosystem disturbance. Importantly, we revealed that submerged sediments may present a greater environmental risk, while alternating wet and dry sediments demonstrate greater resistance and resilience to PLA MPs pollution. Overall, this study sheds light on how sediment ecosystems respond to MP exposure, and highlights differences in sediment response mechanisms across wetting states.

Bisphenol A leachate from polystyrene microplastics has species-specific impacts on scleractinian corals.

Plastic waste causes pervasive environmental contamination and can result in the release of harmful chemical leachates into marine ecosystems, especially as they fragment to smaller microplastics (<5 mm). The toxicity of commonly found polystyrene (PS) microplastics and associated bisphenol A (BPA) leachate to framework-building corals Pocillopora damicornis and Dipsastraea pallida was assessed through exposure experiments. Intermittent exposure over 14-days to 1) virgin PS, 2) preformulated PS with bound BPA (BPA-PS) and 3) leached BPA-PS (L-BPA-PS; simulating early stages of weathering) showed that microplastics void of leachable BPA had minimal effect on either coral species. However, BPA leachate had negative effects on the maximal photochemical yield (Fv/Fm) and tissue composition of P. damicornis fragments (e.g., decreased chlorophyll and protein compared to controls). Conversely, BPA leachate did not compromise tissues of D. pallida fragments. These results reveal that exposure to chemicals leaching out of microplastics can drive negative effects of microplastic exposure distinct from physical mechanisms due to ingestion alone, and that effects are species specific.

Microplastics in fish species from the eastern Guangdong: Implications to Indo-Pacific humpback dolphin (Sousa chinensis) and human health

Microplastic (MP) pollution is widespread in aquatic environments, accumulating in organisms and transferring through the food web. This study investigated MP abundance, composition, and distribution in 15 fish species from eastern Guangdong, 11 of which are prey for Indo-Pacific humpback dolphins (Sousa chinensis). Results indicated the highest MP abundance in fish gastrointestinal tracts, with pelagic species being the most affected. Ethylene vinyl acetate (EVA) and polyethylene (PE), linked to local industrial activities, were the most prevalent polymers. Risk quotients (RQ) at 95th percentile for Indo-Pacific humpback dolphins exceeded one, suggesting significant MP exposure risk via prey ingestion. In contrast, the MPs risk for humans through fish consumption was minimal. These findings underscore the urgent need for improved plastic waste management to protect marine apex predators.

Oral exposure to high concentrations of polystyrene microplastics alters the intestinal environment and metabolic outcomes in mice.

Oral exposure to microplastics (MPs) is a global health concern. In our previous study, MPs induced glucose intolerance and non-alcoholic fatty liver disease (NAFLD) under a high-fat diet-induced leaky gut syndrome (LGS). This study aims to evaluate the effects of high concentrations of MP on lipid metabolism under normal dietary conditions and to assess the changes in the intestinal tract resulting from MP exposure. C57BL6/J mice were fed a normal diet (ND) without polystyrene MPs (PS-MPs) or with PS-MPs (1000 µg/L or 5000 µg/L) for six weeks. Subsequently, intestinal permeability, gut microbiota, and metabolite levels in the serum, feces, and liver were determined. Mice fed the ND showed no increase in intestinal permeability in either group. However, high MPs concentrations led to increased serum lipid levels and exacerbated fatty liver function. Oral exposure to MPs did not affect the number of innate lymphoid cells or short-chain fatty acids in the intestine. However, it increased the number of natural killer cells, altered the gut microbiota, induced inflammation, and modulated the expression of genes related to nutrient transport in the intestine. The severity of intestinal disturbance tended to worsen with dose. Despite the absence of LGS, high concentrations of MPs induced dyslipidemia and NAFLD. Oral exposure to MPs triggered intestinal inflammation via natural killer cells, altered the gut microbiota, and modulated nutrient metabolism. Our study highlights the need for environmental measures to reduce oral MPs exposure in the future.

Evaluation of Microplastic Toxicity in Drinking Water Using Different Test Systems

Microplastic pollution poses a significant threat to environmental and human health. This study investigated the toxicological and genotoxic effects of various microplastic types (polystyrene (PS), polyethylene terephthalate (PET), polypropylene (PP), and polyethylene (PE)) on plant and animal models. Aqueous extracts of microplastics in different size fractions (0.175 mm, 0.3 mm, 1 mm, 2 mm, and 3 mm) were evaluated for their impact on barley seed germination and cell division. Results indicated that smaller microplastic fractions exhibited higher toxicity, particularly for PP and PE. Significant reductions in germination rates and root growth were observed, along with increased chromosomal aberrations in barley cells. Furthermore, the migration of formaldehyde, a known toxicant, from microplastics exceeded permissible limits. These findings highlight the potential risks associated with microplastic pollution, particularly in drinking water sources. Future research should focus on the long-term health impacts of microplastic exposure, including carcinogenic potential, and explore the synergistic effects with other pollutants. Stricter regulations on microplastic pollution and advancements in water treatment technologies are urgently needed to mitigate these risks.