Microplastics: Detection in human samples, cell line studies, and health impacts

Subcellular toxicity assessments of microplastics released from food containers

Plastic food containers are widely used for food packaging and storage; however, concerns have arisen regarding the potential releases of microplastics (MPs) from these containers under varying temperature conditions. This study investigated the release and potential cytotoxicity of MPs from food containers subjected to cooling and heating. Caco-2 cells were selected for in vitro studies to assess the toxicity of MPs from food containers. Each food container released approximately 100,000 to 260,000 plastic particles. The total weight of these plastics was between 0.1 and 0.3 mg of each container after extraction. The results revealed the presence of MPs in both polypropylene (PP) and polystyrene (PS) containers, with frozen food containers releasing a greater quantity of smaller plastic particles. The cytotoxicity of the MPs showed a dose-dependent decrease in cell viability, particularly with MPs from frozen food containers. To further investigate the cellular responses to MPs released from food containers, cellular uptake was visualized using Nile Red staining and confocal microscopy. Changes in cellular organelles and enzyme activities were also observed to reveal the potential effects of MPs. Among all treatments, PS food containers stored in frozen conditions exhibited the most significant cellular responses, including alterations in lysosomal number, size, and reactive oxygen species formation. Compared to cell viability, subcellular responses were found to be more sensitive to MPs. Overall, this study provides valuable insights into the presence, properties, and potential health impacts of MPs released from food containers under microwave heating. The findings underscore the need for further research and regulatory measures to mitigate the risks associated with MPs and promote the development of sustainable alternatives in food packaging.

Detection and quantification of microplastics in meconium by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS)

Microplastics are widely present in the environment and have been found in human biological samples. However, their adverse effects on human remain unclear due to methodological limitations in microplastic analysis. This study aims to develop and validate a Py-GC/MS based analytical method for quantifying 8 typical microplastics in meconium samples. Meconium samples were pretreated via acid digestion, filtration, and analyzed by Py-GC/MS. All 8 microplastics exhibited linear coefficients (R2) exceeding 0.99. Recovery rates (excluding polyethylene terephthalate) ranged from 65.24 % to 114.27 %, with precision values (RSD) of 2.16 % to 14.85 %. Application of this method to 60 meconium samples revealed the presence of all 8 target microplastics, with the concentrations ranging from 1.60 × 10-5 to 1.53 × 103 μg/g and detection rates ranging from 51.67 % to 70.67 %. This method provides a robust technical approach for detecting microplastics in meconium and evaluating associated health risks.

Settleable microplastics in residential buildings in a Middle Eastern area during warm and cool seasons; quantification, characterization, and human exposure assessment

Prolonged daily presence of the general public, combined with the existence of numerous plastic materials in residential buildings, may lead to significant exposure to indoor microplastics (MPs). This may be more heightened for settleable MPs, as they can be inhaled when airborne and ingested after deposition on interior surfaces. To date, such pollution in residential buildings has received limited attention, and the impact of change in season on it has not yet been well explored. Additionally, no information is available about it from the Middle East. In this study, fallout samples were collected over 45 days from residential buildings in Tehran megacity during the warm (spring) and cool (autumn) seasons of 2023. After sample pretreatment, MPs were analyzed by fluorescent microscopy and micro-Raman spectroscopy. The mean indoor MP deposition rate was 2.6 × 103±1.9 × 103 MP/m2/day in spring and significantly reduced to 1.3 × 103±1.0 × 103 MP/m2/day in autumn. The studied buildings were vacuum cleaned at least "once a week", and no significant difference was observed in MP deposition rates between the buildings with "once a week" and "≥twice a week" cleaning frequencies. Fibers and polyethylene terephthalate (PET) were the predominant identified MPs. The mean daily intakes were estimated to be 1.9 × 104±1.6 × 104 and 8.3 × 103±6.4 × 103 MPs in spring and autumn, respectively. Overall, the deposition and exposure rates of settleable MPs in residential buildings varied significantly between warm and cool seasons. The significant rate of exposure to indoor settleable MPs highlights the urgent need for effective measures to reduce human exposure in residential buildings, particularly during warm months.

Explorations in the dark continent: Did microplastics and microfibres get here before us?

Microplastic and microfibre pollution is a global concern, however, karst areas remain understudied. Because of their properties, these anthropogenic microparticles are particularly hazardous, and easily transportable, reaching also remote areas. The underground world, called also dark continent, is a treasure of information, and remained the last frontier of terrestrial exploration: many parts of the underground world have not yet been accessed. In the hypogeal environments, pollution is closely linked to the connections between surface and subterranean habitats, the hydrodynamics of the aquifer, geology, and local environmental conditions. This study aims to investigate, for the first time, the presence of microplastics and microfibres in unexplored caves, revealing how human activity could indirectly impact even the uncontaminated environments of the dark continent. Together with speleologists, we collected and investigated sediment samples from unexplored caves of the Abruzzo Region, Italy. Examined anthropogenic microparticles were counted and characterized by composition, size, shape, fluorescence, and colour, via microscopy and spectroscopy. Microplastic concentrations resulted low or absent, moreover, natural and regenerated microfibres ones were higher. Fibre-shape was the most common. Most of the microparticles were clear and fluorescent under UV light. Pollution sources in this area likely include atmospheric deposition, nearby human activities, roads, and garbage. These results highlight anthropogenic microparticle pollution exists in unexplored karst caves, which could impact subterranean habitats, species, and water resources. Given the link between surface and underground karst environments, more monitoring and protection are needed. This work encourages speleologists to collect samples during explorations too, as these rarely studied environments offer crucial insights into karst systems, potential threats, and conservation needs. Future long-term studies will clarify pollutant sources, transport, and effects on ecosystems.

Spatial and seasonal variations in abundance, distribution characteristics, and sources of microplastics in surface water of Mula river in Pune, India

Microplastics are one class of widely prevalent emerging contaminants that have a detrimental effect on ecosystems and human health. The status of microplastic pollution in rivers in Western India is not well documented, making it difficult for establishing monitoring policies and guidelines. Mula river in Pune is a lifeline for the numerous industries and residential establishments in the city and hence monitoring the health of the water of Mula river is of great societal relevance. This investigation elucidated the prevalence, abundance and characterization of microplastics in Mula River water, while it crosses Pune, one of the fastest developing cities in India. Season played a determinant role in microplastic abundance. During the pre-monsoon season, the average microplastic concentration at all the three selected locations was notably higher (1808 ± 697 particles/L) compared to the post-monsoon period (1561 ± 167 particles/L). Microplastics smaller than 100 μm were consistently dominant in both the seasons. Notably, the most common polymer found in the Mula River was Ethylene Vinyl Acetate (EVA), a copolymer of polyethylene (PE) and vinyl acetate, commonly used in plastic wraps and packaging material. Unregulated disposal of industrial waste emerged as the most potential source of microplastics in Mula river. This study addresses a critical knowledge gap about the distribution and sources of microplastics in rivers in India. This work provides baseline data that can be used to access accurate mitigation of microplastics and evaluate health and environmental impacts of microplastic pollution in Indian rivers.

Advancing microplastic detection in zebrafish with micro computed tomography: A novel approach to revealing microplastic distribution in organisms

The analysis of microplastics with current spectroscopic and pyrolytic methods is reaching its limits, especially with regard to detailed spatial distribution in biological tissues. This limitation hampers a comprehensive understanding of the effects of microplastics on organisms. Therefore, there is a pressing need to expand the analytical approaches to study microplastics in biota. In this context, the aim of this study was to test the applicability of non-destructive 3D imaging using X-ray micro-computed tomography (microCT) for the detection of microplastics in fish. Zebrafish (Danio rerio) were gavaged with polyethylene spherical microplastics (30-110 μm) and the distribution of microplastics in the gut was investigated using microCT. The results showed that the particle size distribution determined by microCT closely matched the data from conventional laser diffraction analysis. In addition, microCT was able to detect microplastics in spiked fish tissue and provide precise localization data by tracing particles of known type and shape. MicroCT offers a novel approach for tracking microplastics in organisms and enables accurate sizing without compromising the integrity of the tissue under investigation. It therefore represents a valuable addition to spectroscopic methods, which are widely used for the detection of microplastics based on their chemical composition but do not provide data on their spatial distribution.

Feasibility of Raman and FTIR spectroscopy for direct microplastic search in the human milk samples: Comparative qualitative study

The ubiquitous presence of microplastic particles encompasses the human tissues and secreta. Unfortunately, the complex biological matrix hampers the proper polymer identification, and harsh purification protocols damage the microplastic particles (MPs), change the specimens frequently used and needed for additional diagnostics, and bias the final result. Moreover, purification of human milk samples is sometimes impossible, as the samples can not be subjected to any chemical pretreatment. Thus, this paper aims to check the feasibility of complementary spectral approaches, namely FTIR (Fourier-transform infrared) and Raman spectroscopy, to the fast scanning of selected MPs presence, in particular polyethylene (PE), and polystyrene (PS), in human milk samples without any previous purification to prevent the change of matrix. Although the proposed approach cannot be used for the quantitative measurement of MPs concentration or the detection of low-size fractions, it is a valuable tool for the preliminary screening of numerous population samples, and some preliminary conclusions can be drawn. One may easily detect the most common MPs and observe their eco-corona. Mapping mode is beneficial for scanning large areas. Furthermore, the spectral methods turned out to be efficient in the milk itself diagnosis, for instance, the monitoring of the fat content. The results were placed in the context of the ongoing broad discussion about MPs interaction with the human body and several possible impact mechanisms.

Microplastic distribution and its implications for human health through marine environments

Microplastics are pervasive pollutants in the ocean, threatening ecosystems and human health through bioaccumulation and toxicological effects. This review synthesizes recent findings on microplastic distribution, trophic transfer, and human health impacts. Key findings indicate that microplastic abundance is highest in the Indian and Pacific Oceans, particularly in seawater and sediment. Morphologically, fibers and fragments dominate, with polypropylene, polyethylene, and polyester being the most prevalent polymers. Smaller particles (<1 mm) undergo long-range transport via ocean currents, while biofouling accelerates vertical sinking. Trophic transfer studies confirm microplastic ingestion across marine food webs. Human exposure is associated with seafood consumption, inhalation of airborne particles, and potential dermal contact, particularly in marine environments. These exposures can lead to adverse health effects, including inflammation, organ damage, respiratory issues, oxidative stress, and metabolic disruptions. Finally, this review explores potential strategies for minimizing human exposure to microplastic pollution in marine environments, paving the way for further research in this critical area.

Urinary microplastic contaminants in primary school children: Associations with behavioral development

Behavioral problems in children have been increasingly linked to environmental exposures. Microplastics (MPs), prevalent in urban environments, are emerging contaminants with potential neurodevelopmental effects. This study examines the relationship between urinary MPs and behavioral outcomes among primary school children in Shenyang, China. This study was conducted involving 1000 children aged 6-9 years from 40 schools across Shenyang. Urinary MPs, including polyamide (PA), polypropylene (PP), and polyvinyl chloride (PVC), were quantified using optical microscopy. Behavioral outcomes were assessed using the Strengths and Difficulties Questionnaire (SDQ). Mixed-effect negative binomial models evaluated associations between MPs and SDQ scores, adjusting for relevant covariates. The median urinary total microplastic concentration was 9 particles/100 mL. Increased particle counts of urinary MPs were positively associated with higher scores for emotional problems, conduct problems, hyperactivity, and peer problems. Total microplastic levels were linked to increased emotional symptoms (estimate: 0.128, 95 % CI: 0.065-0.198, p < 0.001), conduct problems (estimate: 0.231, 95 % CI: 0.140-0.323, p < 0.001), and hyperactivity (estimate: 0.168, 95 % CI: 0.101-0.235, p < 0.001). Peer relationship issues were also elevated with higher urinary microplastic levels (estimate: 0.206, 95 % CI: 0.133-0.271, p < 0.001). Conversely, prosocial behaviors declined with increased microplastic concentrations (estimate: -0.125, 95 % CI: -0.192 to -0.052, p = 0.001). Stratified analyses indicated no significant differences in these associations between boys and girls. Overall, urinary microplastic concentrations were significantly associated with adverse behavioral outcomes in children, highlighting the potential neurodevelopmental risks of microplastic exposure.

Microplastics exacerbate ferroptosis via mitochondrial reactive oxygen species-mediated autophagy in chronic obstructive pulmonary disease

Microplastics (MPs) induce mitochondrial dysfunction and iron accumulation, contributing to mitochondrial macroautophagy/autophagy and ferroptosis, which has increased susceptibility to the exacerbation of chronic obstructive pulmonary disease (COPD); however, the underlying mechanism remains unclear. We demonstrated that MPs intensified inflammation in COPD by enhancing autophagy-dependent ferroptosis (ADF) in vitro and in vivo. In the lung tissues of patients with COPD, the concentrations of MPs, especially polystyrene microplastics (PS-MPs), were significantly higher than that of the control group, as detected by pyrolysis gas chromatography mass spectrometry (Py-GCMS), with increased iron accumulation. The exposure to PS-MPs, 2 μm in size, resulted in their being deposited in the lungs of COPD model mice detected by optical in vivo imaging, and observed in bronchial epithelial cells traced by GFP-labeled PS-MPs. There were mitochondrial impairments accompanied by mitochondrial reactive oxygen species (mito-ROS) overproduction and significantly increased levels of lysosome biogenesis and acidification in pDHBE cells with PS-MP stimulation, triggering occurrence of ferritinophagy and enhancing ADF in COPD, which triggered acute exacerbation of COPD (AECOPD). Reestablishing autophagy-dependent ferroptosis via mitochondria-specific ROS scavenging or ferroptosis inhibition alleviated excessive inflammation and ameliorated AECOPD induced by PS-MPs. Collectively, our data initially revealed that MPs exacerbate ferroptosis via mito-ROS-mediated autophagy in COPD, which sheds light on further hazard assessments of MPs on human respiratory health and potential therapeutic agents for patients with COPD.Abbreviations: ADF: autophagy-dependent ferroptosis; AECOPD: acute exacerbation of chronic obstructive pulmonary disease; Cchord: static compliance; COPD: chronic obstructive pulmonary disease; CQ: chloroquine; CS: cigarette smoke; DEGs: differentially expressed genes; Fer-1: ferrostatin-1; FEV 0.1: forced expiratory volume in first 100 ms; FVC: forced vital capacity; GSH: glutathione; HE: hematoxylin and eosin; IL1B/IL-1β: interleukin 1 beta; IL6: interleukin 6; MDA: malondialdehyde; Mito-ROS: mitochondrial reactive oxygen species; MMA: methyl methacrylate; MMF: maximal mid-expiratory flow curve; MMP: mitochondrial membrane potential; MOI: multiplicity of infection; MPs: microplastics; MV: minute volume; PA: polyamide; PBS: phosphate-buffered saline; PC: polycarbonate; pDHBE: primary human bronchial epithelial cell from COPD patients; PET: polyethylene terephthalate; PIF: peak inspiratory flow; PLA: polylactic acid; pNHBE: primary normal human bronchial epithelial cell; PS-MPs: polystyrene microplastics; PVA: polyvinyl acetate; PVC: polyvinyl chloride; Py-GCMS: pyrolysis gas chromatography mass spectrometry; SEM: scanning electron microscopy; Te: expiratory times; Ti: inspiratory times; TNF/TNF-α: tumor necrosis factor.

Interaction of Polystyrene Nanoplastics with Biomolecules and Environmental Pollutants: Effects on Human Hepatocytes

The inevitable exposure of humans to micro/nanoplastics has become a pressing global environmental issue, with growing concerns regarding their impact on health. While the direct effects of micro/nanoplastics on human health remain largely unknown, increasing attention is being given to their potential role as carriers of environmental pollutants and organic substances. This study investigates the direct toxicity of 500 nm polystyrene nanoplastics (NPs) on human hepatocytes (HepG2) in vitro, both alone and in combination with cadmium (Cd), a hazardous heavy metal and a prevalent environmental pollutant. One-hour exposure to 100 µg/mL of NPs causes a significant increase in ROS production (+25% compared to control) but cell viability remains unaffected even at concentrations much higher than environmental levels. Interestingly, NPs significantly reduce Cd cytotoxicity at LC50 concentrations (cell viability compared to control: 55.4% for 50 µM Cd, 66.9% for 50 µM Cd + 10 µg/mL NPs, 68.4% for 50 µM Cd + 100 µg/mL NPs). Additionally, NPs do not alter the cellular lipid content after short-term exposure (24 h). However, when Cd and fatty acids are added to the medium, NPs appear to sequester fatty acids, reducing their availability and impairing their uptake by cells in a dose-dependent manner. We confirmed by Dynamic Light Scattering and Scanning Electron Microscopy the interaction between NPs, Cd and free fatty acids. Although polystyrene NPs exhibited minimal cytotoxicity in our experimental model, collectively our findings suggest that predicting the effects of cell exposure to NPs is extremely challenging, due to the potential interaction between NPs, environmental pollutants and specific components of the biological matrix.

Identification and analysis of microplastics in human penile cancer tissues

BACKGROUND

Widespread pollution from microplastics (MPs) has been identified as a significant contributor to adverse health effects in humans. This research aimed to investigate the presence of MPs in human penile cancer.

METHODS

The Laser Infrared Imaging Spectrometer (LDIR) was employed to detect and analyze MPs in the cancerous tissue (CT) and adjacent normal tissue (ANT) of 17 patients diagnosed with penile cancer. Subsequently, the abundance, sizes and types of MPs in CT were compared to those in the corresponding ANT.

RESULTS

Nine types of MPs were identified in 85.3 % of the samples analyzed, with an average abundance of 6.42 particles per gram. The most prevalent types of MPs were polyethylene (PE), polypropylene (PP), and polyvinyl chloride (PVC), primarily falling within the 20-50 μm size range. MPs exhibited higher abundance and diversity in CT compared to ANT, with comparable size distributions evident in both of two areas.

CONCLUSION

Our study firstly confirm the presence of MPs in tissue samples from patients with penile cancer. Additionally, the abundance and variety of MPs in cancerous tissue are significantly higher than in adjacent normal tissue, although they had similar size distributions.

The Impact of Microplastics in Food and Drugs on Human Health: A Review of the MENA Region

Microplastics (MPs), defined as plastic particles smaller than 5 mm, have emerged as a global environmental and public health crisis, infiltrating air, water, soil, and food systems worldwide. MPs originate from the breakdown of larger plastic debris, single-use plastics, and industrial processes, entering food. Emerging evidence underscores the ability of MPs to cross biological barriers, including the blood-brain barrier, triggering neuroinflammatory responses and contributing to neurodegenerative diseases such as Alzheimer's and Parkinson's. Polystyrene (PS), a common type of MP, activates microglial cells, releasing pro-inflammatory cytokines like tumor necrosis factor (TNF-α) and interleukins, which increase neuronal damage. MPs have also been linked to cardiovascular diseases, with studies detecting polyethylene (PE) and polyvinyl chloride (PVC) in carotid artery plaques, increasing the risk of myocardial infarction and stroke. Furthermore, MPs disrupt endocrine function, alter lipid metabolism, and induce gut microbiome imbalances, posing multifaceted health risks. In the MENA region, MP pollution is particularly severe, with the Mediterranean Sea receiving an estimated 570,000 tons of plastic annually, equivalent to 33,800 plastic bottles per minute. Studies in Egypt, Lebanon, and Tunisia document high MP concentrations in marine ecosystems, with herbivorous fish like Siganus rivulatus containing over 1000 MPs per individual due to the ingestion of contaminated seaweed. Despite these findings, public awareness and regulatory frameworks remain inadequate, with only 24% of Egyptians demonstrating sufficient knowledge of safe plastic use. This review emphasizes the urgent need for region-specific research, policy interventions, and public awareness campaigns to address MP pollution. Recommendations include sustainable waste management practices, the promotion of biodegradable alternatives, and enhanced monitoring systems to mitigate the health and environmental impacts of MPs in the MENA region.

Polyethylene fragments in Argentinean horticultural soils: Environmental transformation to a composite material

Polyethylene macro, meso, and microplastics collected from horticultural soils in Moreno, Buenos Aires, Argentina, were studied to understand their physicochemical transformations after environmental exposure. These plastics contained mechanically stable compounds of Si (1.2-4.0 %), Al (0.91-1.5 %), and Fe (0.64-2.2 %), likely due to soil clay particles adhering to the plastic. The plastics' surfaces were oxidized, with high carbonyl (0.05-0.23) and hydroxyl (1.6-2.7) indices. Weathering led to thinner, rougher surfaces with increased contact angles due to the presence of clay and polar organic groups. Scanning electron microscopy (SEM) showed cracks and particles on the surfaces, while atomic force microscopy (AFM) revealed roughness increased from 0.44 nm in pristine polyethylene (p-PE) to 1.60 nm in weathered samples. Heavy metal sorption experiments showed that the weathered plastics absorbed significantly more Ni2+ and Pb2+ than unweathered PE (4.5 times for Ni2+ and 11 times for Pb2+). After removing clay with hydrofluoric acid, the plastics still retained the same amount of these metals, suggesting that the sorption occurred mainly on the modified plastic surface rather than the clay. Arsenate tests indicated that the plastics selectively absorbed cationic metals. This study also developed a simple ATR-FTIR method for quantifying silicate on polyethylene surfaces, contributing to an understanding of soil-derived particle interactions with plastic in agricultural settings.

Gestational exposure to nanoplastics disrupts fetal development by promoting the placental aging via ferroptosis of syncytiotrophoblast

Micro(nano)plastics (MNPs), are emerging environmental pollutants that have garnered widespread attention. Epidemiological and animal studies have shown that MNPs exposure during pregnancy is associated with adverse pregnancy outcomes, such as intrauterine growth restriction (IUGR) and miscarriage. However, the underlying mechanisms remain poorly understood. In this study, we found that exposure to a high dose (1 μg·mL-1) of 100 nm polystyrene nanoparticles (NPs) from gestational day (GD) 0 to GD17 significantly decreased fetal weight and increased the number of resorptions compared to the control group. Moreover, fetal weight was significantly lower in the high-dose group than in the low-dose (0.1 μg·mL-1) group. Meanwhile, ferroptosis and senescence were observed in placentas from mice exposed to high dose of NPs. In vitro experiments using human syncytiotrophoblast (STB) cells differentiated from BeWo cells, we found that NPs caused ferroptosis and senescence in STB cells. Subsequent investigations revealed that the inhibition of the ferroptosis signaling by ferrostain-1 (Fer-1) or deferiprone (DFP) ameliorated senescence induced by NPs in human STB cells. Furthermore, alleviating placental senescence using Fer-1 significantly improves fetal weight loss caused by NPs exposure during pregnancy in mice. Taken together, our results demonstrated that NPs exposure during pregnancy activated the ferroptosis pathway in placental STB, resulting in senescence of STB, which may attribute to the NPs-induced IUGR. This study not only elucidated the mechanistic link between NPs exposure and adverse pregnancy outcomes but also highlighted the necessity for targeted interventions to protect fetal health, underscoring the broader implications for environmental and public health policy.

Metabolic Reprogramming in Gut Microbiota Exposed to Polystyrene Microplastics

Background: Microplastics (MPs) are small plastic fragments with diameters less than 5 mm in size and are prevalent in everyday essentials and consumables. Large global plastic production has now led to a flooding of MPs in our natural environment. Due to their detrimental impacts on the planet's ecosystems and potentially our health, MPs have emerged as a significant public health concern. In this pilot study, we hypothesize that MPs exposure will negatively affect gut microbiota composition and function, in which metabolic reprogramming plays an important role. Methods: Using in vitro experiments, three bacterial strains (Escherichia coli MG1655, Nissle 1917, and Lactobacillus rhamnosus) were selected to investigate the impacts of MPs exposure. The bacterial strains were individually cultured in an anaerobic chamber and exposed to 1 µm polystyrene MPs at various concentrations (0, 10, 20, 50, 100, and 500 µg/mL) in the culture medium. Results: MPs exposure reduced the growth of all three bacterial strains in a dose-dependent manner. Liquid chromatography mass spectrometry (LC-MS)-based untargeted metabolomics revealed significant differences in multiple metabolic pathways, such as sulfur metabolism and amino sugar and nucleotide sugar metabolism. In addition, we extracted gut microbiota from C57BL/6 mice, and 16S rRNA sequencing results showed a significant upregulation of Lactobacillales and a significant reduction in Erysipelotrichales due to MPs exposure. Furthermore, targeted and untargeted metabolomics corroborated the in vitro results and revealed alterations in microbial tryptophan metabolism and energy producing pathways, such as glycolysis/gluconeogenesis and the pentose phosphate pathway. Conclusions: These findings provide evidence that MPs exposure causes comprehensive changes to healthy gut microbiota, which may also provide insights into the mechanistic effects of MPs exposure in humans.

Microplastic effects on mouse colon in normal and colitis conditions: A literature review

Background

Taking into account the global spread of microplastic (MP) pollution, the problem of the MP impact on human health is relevant. MP enters the organism predominantly with water and food, and is mostly detected in the large intestine. Therefore, the connection between MP pollution and the increase in colitis is an important question. In order to assess the toxic and pathogenetic effects of MP, experimental studies were actively conducted during recent years, mainly on laboratory mice.

Objectives

The aim of our review was to summarize and systematize the data on the MP effect on mice colon under normal conditions and during colitis in order to assess the role of MP in the development of intestinal diseases. This manuscript could be relevant for ecologists, experimental biologists, and physicians dealing with problems related to anthropogenic environmental changes and inflammatory bowel diseases.

Survey Methodology

The search was conducted based on PubMed data about original experimental studies of the MP effects on the colon of healthy mice and mice with colitis.

Results

In healthy mice colon, MP can cause oxidative stress, increased permeability, immune cell infiltration, production of proinflammatory factors, and decreased mucus production. MP affects proliferation, apoptosis, and differentiation of epithelial cells, expression of tight junction components and glycocalyx, membrane transport, signaling pathways, metabolome, and intestinal microflora composition. In mice with acute and chronic experimental colitis, MP consumption leads to a more pronounced pathological process course.

Conclusions

MP may be one of the factors contributing to the development of colitis in humans. However, further research is needed.

Effects of Microplastic Accumulation on Neuronal Death After Global Cerebral Ischemia

Brain ischemia, a condition in which the brain is deprived of blood flow, can lead to a stroke due to blocked or unstable blood vessels. Global cerebral ischemia (GCI), characterized by an interruption in blood flow, deprives the brain of oxygen and nutrients, producing reactive oxygen species (ROS) that trigger cell death, which kills nerve cells. Microplastics (MPs), tiny environmental pollutants, can enter the human body through contaminated food, water, disposable items, cosmetics, and more. Once in the brain, MPs can increase neuroinflammation by overstimulating inflammatory factors such as microglia. MPs can also damage neurons by scratching myelin and microtubules, slowing signal transduction, causing cognitive impairment, and leading to neuronal death. Furthermore, microtubule damage may result in the release of phosphorylated tau proteins, potentially linked to Alzheimer's disease. We hypothesized that MPs could exacerbate neuroinflammation and microtubule destruction after GCI, leading to increased neuronal death. To test this hypothesis, we administered MPs (0.5 µm) orally at a dose of 50 mg/kg before and after inducing GCI. Staining techniques such as Fluoro-Jade B (FJB), ionized calcium-binding adaptor molecule 1 (Iba-1), cluster of differentiation 68 (CD68), myelin basic protein (MBP), and microtubule-associated protein 2 (MAP2) were used, along with Western blot analysis for interleukin-6 (IL-6), TNF-α, tau-5, and phospho-tau (S396) to evaluate the effects of MPs on neuronal cell death, neuroinflammation, and microtubule destruction. The results showed that MP accumulation significantly increased neuroinflammation, microtubule disruption, and neuronal cell death in the GCI-MP group compared to the GCI-vehicle group. Therefore, this study suggests that MP accumulation in daily life may contribute to the exacerbation of the disease, potentially leading to severe neuronal cell death after GCI.

Characterization of microplastics in human follicular fluid and assessment of their potential impact on mouse oocyte maturation in vitro

Microplastics (MPs) have been identified in various human tissues and organs. This study aims to evaluate the presence of MPs in human follicular fluid (hFF) and their potential impact on oocyte maturation. Laser direct infrared spectroscopy of 19 hFF samples identified 7956 particles, including 1739 microplastics (21.9 %) from 30 types. Of these, 923 particles had matching degrees > 0.8, and 7033 had matching degrees between 0.65 and 0.8. The most abundant MPs were Chlorinated Polyethylene (CPE), Fluorosilicone rubber, Polyvinyl chloride (PVC), Butadiene rubber (BR), and Styrene-butadiene-styrene (SBS), with diameters ranging from 20 to 100 μm. Five random samples were analyzed by pyrolysis-gas chromatography-mass spectrometry, which detected four types of microplastics-Polyethylene (PE), Polypropylene (PP), Polystyrene (PS), and PVC-at varying concentrations. PE was the most abundant (22.284 mg/kg), followed by PVC (1.061 mg/kg), PP (0.837 mg/kg), and PS (0.600 mg/kg). Based on the diameter and concentration ranges of MPs in hFF, we used seven types of fluorescence-labeled MP beads-PE, PVC, PP, PS, CPE, Polymethylmethacrylate (PMMA), and Polytetrafluoroethylene (PTFE)-to assess their impact on mouse oocyte in vitro maturation. The results showed that smaller MP beads (e.g., 50 μm PE) were more likely to penetrate the zona pellucida and enter the oocyte, while larger beads (e.g., 500 nm PMMA) tended to adhere to the zona and remain outside the oocyte. All seven types of MP beads hindered oocyte maturation, resulting in varying reductions in maturation rates compared to the control group. Our findings suggest that MPs contaminate hFF and may impair oocyte maturation.

The microplastic-crisis: Role of bacteria in fighting microplastic-effects in the digestive system

Plastic particles smaller than 5 mm, referred to as Microplastics, pose health risks, like metabolic, immunological, neurological, reproductive, and carcinogenic effects, after being ingested. Smaller plastic particles are more likely to be absorbed by human cells, with nanoplastics showing higher potential for cellular damage, including DNA fragmentation and altered protein functions. Micro- and nanoplastics (MNPs) affect the gastrointestinal tract by altering the microbial composition, they could influence digestive enzymes, and possibly disrupt mucus layers. In the stomach, they potentially interfere with digestion and barrier functions, while in the intestines, they could increase permeability via inflammation and tissue disruption. MNPs can lead to microbial dysbiosis, leading to gastrointestinal symptoms. By activating inflammatory pathways, altering T cell functions and affecting dendritic cells and macrophages, immune system homeostasis could possibly be disrupted. Probiotics offer potential strategies to alleviate plastic effects, by either degrading plastic particles or directly countering health effects. We compared genetic sequences of probiotics to the genome of known plastic degraders and concluded that no probiotic bacteria could serve the role of plastic degradation. However, probiotics could directly mitigate MNP-health effects. They can restore microbial diversity, enhance the gut barrier, regulate bile acid metabolism, reduce inflammation, regulate insulin balance, and counteract metabolic disruptions. Antioxidative properties protect against lipid peroxidation and MNP-related reproductive system damage. Probiotics can also bind and degrade toxins, like heavy metals and bisphenol A. Additionally, bacteria could be used to aggregate MNPs and reduce their impact. Therefore, probiotics offer a variety of strategies to counter MNP-induced health effects.

A Simple Technique for Studying the Interaction of Polypropylene-Based Microplastics with Adherent Mammalian Cells Using a Holder

Microplastics pose a great challenge to human health and could prove to be the most dangerous environmental contaminant of the 21st century. The study presented here is an attempt at proposing a new methodology for studying the interaction of microplastics with adherent mammalian cells using aides. The disposable holders proposed here provide direct contact between microplastics (with a density lower than that of water) and cells in the course of culturing, which is necessary as we postulate the existence of an interaction. Using several microscopic methods (confocal fluorescence microscopy and scanning electron microscopy (SEM)), we have observed that this interaction causes a non-destructive penetration of the cell monolayer and adhesion of microplastics to the cell surface. The Caco-2 cells were used for the experiments. The said cells are the approximation of the digestive system, which, due to the presence of plastics in drinking water, is particularly vulnerable to direct interactions with these contaminants. Model microplastics were obtained by grinding pellets of chemically pure polypropylene. The imaging of cells in both space and on the surface was supplemented by an assay to determine the cell welfare in the studied microplastic-exposed models, which did not show the occurrence of apoptosis or necrosis after a 24 h exposure.

Impact of microplastics on female reproductive health: insights from animal and human experimental studies: a systematic review

OBJECTIVE

This systematic review aims to evaluate the impact of microplastics on female reproductive health by analyzing experimental studies.

METHOD

A comprehensive search was conducted in PubMed, Web of Science, and Scopus databases to identify experimental studies published between 2021 and 2023. Studies investigating the effects of microplastics on reproductive organs, hormone levels, fertility rates, and offspring development in female subjects were included. The quality of the studies was assessed using the Cochrane risk of bias tool.

RESULTS

A total of 15 studies met the inclusion criteria. The results indicate that exposure to microplastics significantly affects ovarian function, decreases fertility rates, and disrupts hormone levels in female subjects. Several studies also reported negative effects on embryo development and offsprings health. The quality of the studies varied, with some showing a high risk of bias.

CONCLUSION

The evidence from experimental studies suggests that microplastics have a detrimental effect on female reproductive health. However, the variation in study quality highlights the need for more rigorous research to confirm these results and better understand the underlying mechanisms.

Microplastics in soils: A comprehensive review

Microplastics (MPs) have become pervasive pollutants in terrestrial ecosystems, raising significant ecological risks and human health concerns. Despite growing attention, a comprehensive understanding of their quantification, sources, emissions, transport, degradation, and accumulation in soils remains incomplete. This review synthesizes the current knowledge on the anthropogenic activities contributing to soil MP contamination, both intentional and unintentional behaviors, spanning sectors including agriculture, domestic activities, transportation, construction, and industry. Furthermore, it examines the spatial distribution, accumulation, and abundance of MPs across various land use types, alongside a critical assessment of existing quantification methodologies. While the predominant metric for MP quantification is particle number concentration, integrating mass and area concentration enhances the ability to compare pollution levels, assess fluxes, and conduct risk analyses. Additionally, the review explores the transport behavior of MPs in soil, distinguishing between external mechanisms (abiotic factors: wind, leaching, and runoff, biotic factors: soil bioturbation and food chain interactions), and internal mechanisms that are impacted by the characteristics of MPs themselves (e.g., shape, color, size, density, surface properties), soil properties (e.g., porosity, pH, ionic strength, organic matter and mineral content), coexisting substances, and soil structural dynamics. The study of MP transport in soil remains in its early stages, with substantial gaps in knowledge. Future research should focus on integrating number, mass concentration, and area concentration for the more holistic quantification of MP abundance, and prioritize the development of more accurate and efficient methodologies. In addition, the investigation of MP transport and degradation processes under varying environmental conditions and soil management practices is critical for addressing this emerging environmental challenge.

Investigating the inflammatory effect of microplastics in cigarette butts on peripheral blood mononuclear cells

Cigarette filter microplastics are composed of cellulose acetate that does not undergo biological or photo-degradation. These microplastics are readily dispersed and can be found abundantly in water, soil, and air. These fibers possess high absorption capabilities, allowing them to collect and retain pollutants such as toxic elements. As a result, they are regarded as potential dangers to living organisms. The purpose of this study was to analyze the immune response of human peripheral blood mononuclear cells (PBMCs) when exposed to cigarette filter microfibers, measuring the secretion of the inflammatory cytokines TNFα (tumor necrosis factor-alpha) and IL-6 (interleukin-6). In this study, we examined how used cigarette cellulose acetate microfibers affect the viability of peripheral blood mononuclear cells in an appropriate culture medium at three concentrations: 50, 100, and 200 µg/ml. In addition, this study investigated the release of inflammatory cytokines TNFα and IL6 from PBMCs exposed to 200 µg/ml cigarette filter cellulose acetate. The results showed that increasing the concentration of cellulose acetate fibers of one of the brands in the culture medium has a significant effect on reducing cell viability. The 200 µg/ml in DW is more effective than 50 and 100 µg/ml in reducing cell viability. Peripheral blood mononuclear cells showed an inflammatory immune response when exposed to 200 µg/ml cellulose acetate from cigarette filters. They produced inflammatory cytokines that showed a significant increase compared to the control sample. In general, it can be concluded that cellulose acetate fibers in contact with body cells stimulate them and cause an inflammatory response.

Microplastics accumulated in breast cancer patients lead to mitophagy via ANXA2-mediated endocytosis and IL-17 signaling pathway

Breast cancer (BC) is the most common malignancy in women and the leading cause of cancer death. Microplastics (MPs) are plastic fragments with a diameter of less than 5 mm, easily ingested by organisms. Although MPs have been reported to enter the human body through diet, surgery, etc., whether MPs accumulate in BC and their effects have been largely unknown. Our study revealed a significant accumulation of MPs in BC patient samples. MPs pull-down experiments and mass spectrometry (MS) studies showed that MPs bound to annexin A2 (ANXA2) and were endocytosed into cells. This process resulted in mitochondrial damage and subsequent induction of mitophagy. Furthermore, after binding to ANXA2, MPs regulated mitophagy by inhibiting IL-17 exocytosis. These findings revealed the mechanism of toxic effects of MPs in patients with BC, clarified the molecular mechanism of ANXA2-IL-17 signaling pathway causing mitochondrial damage by MPs, and suggested the potential toxic effects and toxicological mechanisms of MPs.

Polyethylene microplastic exposure adversely affects oocyte quality in human and mouse

Microplastics (MPs) are pervasive environmental contaminants, resulting in unavoidable human exposure. This study identified MPs in follicular fluid and investigated the specific MPs and mechanisms that adversely affect oocytes. MPs in the follicular fluid of 44 infertile women undergoing assisted reproductive technology were measured using Raman microspectroscopy. Differential metabolites in follicular fluid were analyzed via untargeted metabolomics. Female mice were exposed to polyethylene (PE) to validate human findings. MPs, particularly PE, exhibited the highest detection rate (86.4 %) in human follicular fluid and showed a negative correlation with fertilization rates (r = -0.407, P = 0.007). Elevated PE levels altered metabolites primarily involved in metabolic pathways, ferroptosis, and ovarian steroidogenesis. In mice, PE exposure significantly reduced the number of retrieved oocytes (31.5 vs. 36.3, P < 0.05) and fertilization rate (70.8 % vs. 85.2 %, P < 0.001), while increasing the proportion of poor-quality oocytes (28.2 % vs. 16.5 %, P < 0.001) and reactive oxygen species (ROS) production compared to controls. RNA sequencing indicated significant upregulation of inflammation-related genes (Il10ra, Il1a, Il33, Tnfaip8l2, and Tnfrsf1b) in the PE-exposed group. In conclusion, PE exposure impairs oocyte quality possibly by disrupting follicular fluid metabolism, elevating inflammation-related gene expression, and increasing ROS production in oocytes.

Food packaging solutions in the post-per- and polyfluoroalkyl substances (PFAS) and microplastics era: A review of functions, materials, and bio-based alternatives

Food packaging (FP) is essential for preserving food quality, safety, and extending shelf-life. However, growing concerns about the environmental and health impacts of conventional packaging materials, particularly per- and polyfluoroalkyl substances (PFAS) and microplastics, are driving a major transformation in FP design. PFAS, synthetic compounds with dual hydro- and lipophobicity, have been widely employed in food packaging materials (FPMs) to impart desirable water and grease repellency. However, PFAS bioaccumulate in the human body and have been linked to multiple health effects, including immune system dysfunction, cancer, and developmental problems. The detection of microplastics in various FPMs has raised significant concerns regarding their potential migration into food and subsequent ingestion. This comprehensive review examines the current landscape of FPMs, their functions, and physicochemical properties to put into perspective why there is widespread use of PFAS and microplastics in FPMs. The review then addresses the challenges posed by PFAS and microplastics, emphasizing the urgent need for sustainable and bio-based alternatives. We highlight promising advancements in sustainable and renewable materials, including plant-derived polysaccharides, proteins, and waxes, as well as recycled and upcycled materials. The integration of these sustainable materials into active packaging systems is also examined, indicating innovations in oxygen scavengers, moisture absorbers, and antimicrobial packaging. The review concludes by identifying key research gaps and future directions, including the need for comprehensive life cycle assessments and strategies to improve scalability and cost-effectiveness. As the FP industry evolves, a holistic approach considering environmental impact, functionality, and consumer acceptance will be crucial in developing truly sustainable packaging solutions.

Analysis of microplastic contamination and associated human health risks in Clarias gariepinus and Oreochromis niloticus from Kubanni Reservoir, Zaria Nigeria

Environmental safety has become a major concern in recent years due to the global increase in microplastic pollution. These ubiquitous, tiny, and potentially toxic plastic particles enter aquatic environments through weathering of larger plastics and the release of microbeads. Although numerous studies have focused on microplastic pollution in developed regions, information from developing countries remains limited. This study assessed the presence of MPs and associated oxidative stress responses in two commercial fish species, Clarias gariepinus (Catfish) and Oreochromis niloticus (Nile Tilapia), from Kubanni reservoir, Zaria, Nigeria, over six months spanning both the dry and rainy seasons. Fibers were identified as the most abundant MP particles, followed by fragments, films, and beads, in the order of fibers > fragments > films > beads. The highest fiber concentrations were recorded in the gills, with Clarias garipinus showing 11.5 MP items/individual and Oreochromis niloticus showing 22.5 MP items/individual. Black microplastics were predominant, and the most common ingested MP ranged from 1.0 to 2.0 mm. The primary polymers identified were polypropylene and polyethylene terephthalate. Evidence of oxidative stress and cellular damage was observed in the gills, liver, and dorsal muscles of both fish species, which correlated with MPs ingestion. According to recommendations from the European Food Safety Authority regarding fish consumption by children and adults, individuals consuming Clarias gariepinus and Oreochromis niloticus from the Kubanni reservoir may be exposed to between 70 and 700 MP items/organ. The risk associated with consuming MPs found in fish gills and guts was notably higher, posing significant concerns for human health. This study provides insights into microplastic contamination in commercially important fish from the Kubanni Reservoir and highlights the environmental and public health risks associated with consuming contaminated fish from this ecosystem.

Mechanistic insight of neurodegeneration due to micro/nano-plastic-induced gut dysbiosis

Despite offering significant conveniences, plastic materials contribute substantially in developing environmental hazards and pollutants. Plastic trash that has not been adequately managed may eventually break down into fragments caused by human or ecological factors. Arguably, the crucial element for determining the biological toxicities of plastics are micro/nano-forms of plastics (MPs/NPs), which infiltrate the mammalian tissue through different media and routes. Infiltration of MPs/NPs across the intestinal barrier leads to microbial architectural dysfunction, which further modulates the population of gastrointestinal microbes. Thereby, it triggers inflammatory mediators (e.g., IL-1α/β, TNF-α, and IFN-γ) by activating specific receptors located in the gut barrier. Mounting evidence indicates that MPs/NPs disrupt host pathophysiological function through modification of junctional proteins and effector cells. Moreover, the alteration of microbial diversity by MPs/NPs causes the breakdown of the blood-brain barrier and translocation of metabolites (e.g., SCFAs, LPS) through the vagus nerve. Potent penetration affects the neuronal networks, neuronal protein accumulation, acceleration of oxidative stress, and alteration of neurofibrillary tangles, and hinders distinctive communicating pathways. Conclusively, alterations of these neurotoxic factors are possibly responsible for the associated neurodegenerative disorders due to the exposure of MPs/NPs. In this review, the hypothesis on MPs/NPs associated with gut microbial dysbiosis has been interlinked to the distinct neurological impairment through the gut-brain axis.

Examining the hidden dangers: Understanding how microplastics affect pregnancy

Microplastics, a fast-growing environmental concern, play a crucial role in developing the major pollution crisis that affects nearly the entire surface of the planet. Microplastics are tiny particles, measuring less than 5 mm which are ubiquitous, in occurrence, and found in a wide array of products including plastic packaging, synthetic textiles, seafood, fruits, vegetables, salt, sugar, bottled water, and even personal care products. The presence of microplastics in our environment and the potential adverse health effects they may cause have made them a significant perturbation in recent years. Pregnancy is a potentially life-changing experience that entails several apprehensions and new responsibilities for women. For expectant mothers, it is imperative to be aware of the implications of microplastics during pregnancy. One threatened concern is the potential transfer of microplastics across the placenta, which could expose the developing fetus to these particles. Although research on the impact of microplastics on pregnancy is still in its early stages, preliminary findings indicate potential risks that expectant mothers should be aware of. The timing of exposure during pregnancy may play a significant role in the potential risks associated with these tiny particles. In this review, we will delve into the topic, exploring how microplastics enter the body and the potential mechanism by which they pose risks to pregnancy outcomes.

Prevalence and characteristics of microplastic contamination in soft drinks and potential consumer exposure

Microplastics (MPs) contamination in human food is a growing concern due to potential health risks. Recent studies have indicated that MPs have been found in various human tissues and organs, including the placenta, lungs, liver, and blood. This highlights the importance of investigating the presence and concentration of MPs in food products, as it directly relates to human health and safety. In this study, MP contamination was detected and characterized in commercially available soft drinks in Thailand. Nine popular soft drink brands in Thailand, packaged in different materials, including plastic bottles, aluminum cans, and glass bottles, were investigated. The results revealed that regardless of packaging type, all the soft drink brands tested contained MPs, with concentrations ranging from 2 ± 3 to 39 ± 12 items per liter. MPs in the 50-100 μm size range, primarily with a fragment-like morphology, were most commonly found. Given that the average person in Thailand consumes approximately 41.13 L of soft drinks annually, it is estimated that an individual could ingest between 81 and 1609 MPs yearly. These findings raise significant concerns about the potential health impacts of MP ingestion through soft drinks and underscore the need for further research and regulation.

Analytical Challenges and Strategies for Particle-Based Analysis of Airborne Micro(nano)plastics in Size-Fractionated Samples Using Microscopy, SEM/EDX, and Raman Spectroscopy

Inhalable micro(nano)plastics (MNPs) have emerged as a significant global concern due to their abundance and persistence in the atmosphere. Despite a growing body of literature addressing the analytical requirements of airborne MNPs, the issue of inhalable fractions and analysis of slotted substrates remains unclear. Therefore, the objective of this study is to perform a systematic particle-based analysis and characterization of inhalable microplastics (MPs) collected by a high-volume sampler equipped with a five-stage cascade impactor with a size range of 10 μm to <0.49 μm. The efficacy of collection substrates (Teflon and aluminum) was evaluated, as was the impact of particle transfer from the slotted filters on the analysis area and pretreatment methods including chemical digestion for further analysis. The distribution of MNP particles across different slots of a Teflon filter was investigated using Raman microspectrometry to select an appropriate subsample. The results showed the suitability of Teflon filters without any pretreatment for particles down to a single micrometer. As observed by the SEM/EDX analysis, the airborne particles collected in a filter with a submicrometer range (<0.95 μm) showed a decrease in carbon-rich components compared to those stages with higher cutoff sizes. A minimum of 20 particles were analyzed per 1 cm2 of the slotted filter using Raman spectrometry, which revealed a homogeneous distribution of MPs across different slots and yielded a concentration of 452 ± 134 MP/m3 in the first stage of the cascade sampler. The detected MPs were morphologically classified into two main groups: fragments with a size range of 2.8-24.8 μm and fibers with a size range of 28.6-212 μm. Subsequently, the particles were chemically identified as carbon black (tires) and polypropylene. In conclusion, particle-based analysis of size-segregated airborne MNPs presents certain challenges when attempting to analyze particles as small as a single micrometer due to the fact that the aerodynamic diameter of the particles in question and the corresponding analytical limitations that result from this become particularly problematic, especially for cutoffs smaller than 3 μm.

A multiple biomarker approach to understand the effects of microplastics on the health status of European seabass farmed in earthen ponds on the NE Atlantic coast

The occurrence of microplastics (MPs) in aquaculture environments is a growing concern due to their potential negative effects on fish health and, ultimately, on seafood safety. Earthen pond aquaculture, a prevalent aquaculture system worldwide, is typically located in coastal and estuarine areas thus vulnerable to MP contamination. The present study investigated the possible relation between MP levels of European seabass (Dicentrarchus labrax) farmed in an earthen pond and its health status. More precisely, two groups of fish were established based on the lowest and highest number of MPs found collectively in their gastrointestinal tract (GIT), liver, and dorsal muscle: fish with ≤2 MP/g and fish with ≥4 MP/g. The intestinal integrity and oxidative stress biomarkers in the liver and dorsal muscle were evaluated in the established groups. No significant differences in the biometric and organosomatic parameters between groups were observed. The results indicated a significant increase in the number of acid goblet cells (GC) in the rectum of fish with higher MP levels (p = 0.016). Increased acid GC number may constitute a first defence strategy against foreign particles to protect the intestinal epithelium. No significant differences in oxidative stress biomarkers between the two fish groups were observed, namely in the activity of superoxide dismutase, catalase, glutathione reductase, and glutathione S-transferase in the liver, or in lipid peroxidation levels in the liver and dorsal muscle. The overall results suggest that MP levels were possibly related to an intestinal response but its potential implications on the health status of pond-farmed seabass warrant further investigation. Monitoring MP occurrence across stages of aquaculture production could help to elucidate the potential threats of MPs to fish health.

Exploring action-law of microplastic abundance variation in river waters at coastal regions of China based on machine learning prediction

Surface waters, particularly the river systems, constitute a vital freshwater resource for human beings and aquatic life on Earth. In economically developed and densely populated coastal regions, river water is facing severe microplastic pollution, posing a threat to public health and ecological safety. Reliable prediction of microplastic abundance (MPA) can significantly reduce the costs associated with microplastic field sampling and analysis. This study employed spatial correlation, geographical detector, principal component analysis and five mainstream machine learning models to analyze 79 datasets of MPAs in seven coastal areas of China and performed correlation, regression and attribution analyses based on 19 terrestrial influencing factors that potentially affect the MPA life cycle processes (generation, aging, and migration). The results showed that the Neural Network (NN) and the Gaussian Process Regression (GPR) models achieved the best prediction performance, with the predicted R2 close to 1. Principal component analysis and Shapley additive explanations concluded that meteorological factors, in particular the annual geotemperature, surface solar radiation, and annual relative humidity, had a key influence on the aging of microplastics. The second key factor in improving the MPA prediction ability was the dynamic description of microplastic migration, which was primarily governed by hydrological factors such as annual precipitation and average terrain slope. Unexpectedly, the effects of land use and level of urbanization were relatively small in describing the generation of microplastics. Only the percentage of built areas was strongly correlated with the MPA levels. Note that the MPA prediction and its contribution factors may vary across different basins. Nevertheless, the findings of this study are applicable to predicting and analyzing the distribution of microplastics in other coastal rivers, and for indicating the main contributing factors, ultimately serving as a basis for guiding microplastic pollution control strategies in different river basins.

Microplastics in the urban water cycle: A critical analysis of issues and of possible (needed?) solutions

Microplastic (MP) contamination is a problem that affects even remote, scarcely populated regions of the world. This topic has recently been the subject of many published studies, however, these often adopt hyperbolic statements and do not actually provide definitive evidence that MPs are a cause of environmental risk in actual environmental conditions. New technologies to remove MPs from supply and waste water are being investigated, but they are able to intercept a minimal fraction of the MPs circulating in all environmental media. Recently, several pieces of legislation were introduced to reduce plastic production, use, and disposal, but it is not clear how such measures could achieve a significant environmental MP reduction. This paper addresses the MP issue within the urban water cycle, examining recent current literature on MP presence in drinking and waste water, and overviewing available recent treatment technologies for their removal. The ensuing discussion attempts to holistically assess the actual relevance of the issue in the light of the current scientific evidence.

Biological hazards of micro- and nanoplastic with adsorbents and additives

With the increased worldwide production of plastics, interest in the biological hazards of microplastics (MP) and nanoplastics (NP), which are widely distributed as environmental pollutants, has also increased. This review aims to provide a comprehensive overview of the toxicological effects of MP and NP on in vitro and in vivo systems based on studies conducted over the past decade. We summarize key findings on how the type, size, and adsorbed substances of plastics, including chemical additives, impact organisms. Also, we address various exposure routes, such as ingestion, inhalation, and skin contact, and their biological effects on both aquatic and terrestrial organisms, as well as human health. Additionally, the review highlights the increased toxicity of MP and NP due to their smaller size and higher bioavailability, as well as the interactions between these particles and chemical additives. This review emphasizes the need for further research into the complex biological interactions and risks posed by the accumulation of MP and NP in the environment, while also proposing potential directions for future studies.

Microplastics in the Human Body: Exposure, Detection, and Risk of Carcinogenesis: A State-of-the-Art Review

Background: Humans cannot avoid plastic exposure due to its ubiquitous presence in the natural environment. The waste generated is poorly biodegradable and exists in the form of MPs, which can enter the human body primarily through the digestive tract, respiratory tract, or damaged skin and accumulate in various tissues by crossing biological membrane barriers. There is an increasing amount of research on the health effects of MPs. Most literature reports focus on the impact of plastics on the respiratory, digestive, reproductive, hormonal, nervous, and immune systems, as well as the metabolic effects of MPs accumulation leading to epidemics of obesity, diabetes, hypertension, and non-alcoholic fatty liver disease. MPs, as xenobiotics, undergo ADMET processes in the body, i.e., absorption, distribution, metabolism, and excretion, which are not fully understood. Of particular concern are the carcinogenic chemicals added to plastics during manufacturing or adsorbed from the environment, such as chlorinated paraffins, phthalates, phenols, and bisphenols, which can be released when absorbed by the body. The continuous increase in NMP exposure has accelerated during the SARS-CoV-2 pandemic when there was a need to use single-use plastic products in daily life. Therefore, there is an urgent need to diagnose problems related to the health effects of MP exposure and detection. Methods: We collected eligible publications mainly from PubMed published between 2017 and 2024. Results: In this review, we summarize the current knowledge on potential sources and routes of exposure, translocation pathways, identification methods, and carcinogenic potential confirmed by in vitro and in vivo studies. Additionally, we discuss the limitations of studies such as contamination during sample preparation and instrumental limitations constraints affecting imaging quality and MPs detection sensitivity. Conclusions: The assessment of MP content in samples should be performed according to the appropriate procedure and analytical technique to ensure Quality and Control (QA/QC). It was confirmed that MPs can be absorbed and accumulated in distant tissues, leading to an inflammatory response and initiation of signaling pathways responsible for malignant transformation.

Microplastics in ecosystems: Critical review of occurrence, distribution, toxicity, fate, transport, and advances in experimental and computational studies in surface and subsurface water

Microplastics (MPs), particles under 5 mm, pervade water, soil, sediment, and air due to increased plastic production and improper disposal, posing global environmental and health risks. Examining their distribution, quantities, fate, and transport is crucial for effective management. Several studies have explored MPs' sources, distribution, transport, and biological impacts, primarily focusing on the marine environment. However, there is a need for a comprehensive review of all environmental systems together for enhanced pollution control. This review critically examines the occurrence, distribution, fate, and transport of MPs in the following environments: freshwater, marine, and terrestrial ecosystems. The concentration of MPs is highly variable in the environment, ranging from negligible to significant amounts (0.003-519.223 items/liter in water and 0-18,000 items/kg dry weight sediment, respectively). Predominantly, these MPs manifest as fibers and fragments, with primary polymer types including polypropylene, polystyrene, polyethylene, and polyethylene terephthalate. A complex interplay of natural and anthropogenic actions, including wastewater treatment plant discharges, precipitation, stormwater runoff, inadequate plastic waste management, and biosolid applications, influences MPs' presence and distribution. Our critical synthesis of existing literature underscores the significance of factors such as wind, water flow rates, settling velocities, wave characteristics, plastic morphology, density, and size in determining MPs' transport dynamics in surface and subsurface waters. Furthermore, this review identifies research gaps, both in experimental and simulation, and outlines pivotal avenues for future exploration in the realm of MPs.

Reproductive and developmental implications of micro- and nanoplastic internalization: Recent advances and perspectives

A growing body of evidence exhibits the ubiquitous presence and accumulation of micro- and nanoplastics (MNPs) in the air, drinking water, food, and even inside the body, which has raised concerns about their potential impact on reproductive and developmental health. To comprehensively examine the current state of knowledge regarding MNPs-induced reproductive and developmental toxicity, we conducted this systematic review by focusing on the prevalence of MNPs determined in reproductive tissues and their influences on parental reproduction and offspring development. Our findings demonstrate the detection of MNPs in various human reproductive tissues, including semen, placenta, and ovarian follicular fluid, as well as in reproductive tissues of diverse animal species. We show a potential relationship between MNP exposure and increased prevalence of infertility and adverse pregnancy outcomes based on the fact that MNPs exert detrimental effects on reproductive parameters, including sperm quality, ovarian function, and steroidogenesis. In male reproductive systems, MNPs disrupt testicular tissue structure, impair reproductive endocrinology, and reduce sperm quality. In females, MNPs affect ovarian tissue structure and function, interfere with hormone secretion, and impact the endometrium and embryo implantation. Additionally, MNPs cause developmental toxicity in animal models, affecting embryonic development and offspring health, and produce transgenerational effects. Notably, in-depth literature study suggests a crucial role for oxidative stress, inflammation, and epigenetic modification in MNPs-induced toxicity. In conclusion, we integrated systematic knowledge on MNPs-induced reproductive and developmental toxicity, and the systematic finding underscores future study to fully elucidate the risks posed by MNPs to reproductive and developmental health and to inform policy decisions and public health interventions aimed at mitigating their harmful effects.

Inhalation of Microplastics Induces Inflammatory Injuries in Multiple Murine Organs via the Toll-like Receptor Pathway

Previous studies have detected microplastics (MPs) in human biological samples, such as lungs, alveolar lavage fluid, and thrombus. However, whether MPs induce health effects after inhalation are unclear. In this study, fluorescent polystyrene microplastics (PS-MPs) were found in the thymus, spleen, testes, liver, kidneys, and brain on day 1 or day 3 after one intratracheal instillation. Furthermore, mice showed inflammation in multiple organs, manifested as obvious infiltration of neutrophils and macrophages, increased Toll-like receptors (TLRs), myeloid differentiation primary response protein 88 (MyD88) and nuclear factor-κB (NF-κB), as well as proinflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-1β) in the lungs, thymus, spleen, liver, and kidneys after four intratracheal instillations of PS-MPs at once every 2 weeks. Hepatic and renal function indexes were also increased. Subsequently, the inflammatory response in multiple murine organs was significantly alleviated by TLR2 and TLR4 inhibitors. Unexpectedly, we did not find any elevated secretion of monocyte chemotactic protein (MCP)-1 or TNF-α by RAW264.7 macrophages in vitro. Thus, PS-MPs induced inflammatory injuries in multiple murine organs via the TLRs/MyD88/NF-κB pathway in vivo, but not macrophages in vitro. These results may provide theoretical support for healthy protection against PS-MPs and their environmental risk assessment.

Microplastic exposure linked to accelerated aging and impaired adipogenesis in fat cells

Our research explores the detrimental effects of microplastic (MP) exposure on adipose tissue aging and function, emphasizing the potential health risks associated with environmental pollutants. Utilizing both in vivo and in vitro models, we discovered that MPs accumulate in adipose tissues, leading to cellular senescence, inflammation, and hindered adipogenic differentiation. Notably, our findings demonstrate that MPs prompt an aging response in both epididymal and inguinal white adipose tissue, increase senescence-associated β-galactosidase activity, and upregulate key senescence and inflammatory markers. Furthermore, we show that MPs disrupt normal adipogenic differentiation by reducing lipid droplet formation and downregulating critical adipogenic markers. These insights highlight the urgent need for further investigation into the long-term consequences of MP pollution on biological aging and underscore the importance of developing public health strategies to mitigate these effects.

Million Microfiber Releases: Comparing Washable and Disposable Face Masks

The extensive use of single-use or disposable face masks has raised environmental concerns related to microfiber contamination. In contrast, research on the potential release and ecological impact of microfibers from washable masks (WMs), suggested as an eco-friendly alternative, is currently lacking. Here, we comprehensively investigated the release of microfibers from disposable and WMs of different types in simulated aquatic environments and real-life scenarios, including shaking, disinfection, hand washing, and machine washing. Using a combination of wide-field fluorescence microscopy, He-ion microscopy, and confocal μ-Raman spectroscopy, we revealed that disposable masks (DMs) released microfibers ranging from 18 to 3042 microfiber/piece, whereas WMs released 6.1 × 104-6.7 × 106 microfibers/piece depending on the simulated conditions above. Another noteworthy finding was the observed negative correlation between microfiber release and the proportion of reinforcement (embossing) on the DM surfaces. Microfibers from tested DMs primarily comprised polypropylene (PP), while WMs predominantly released poly(ethylene terephthalate) (PET) and cellulose microfibers. Furthermore, acute toxicological analyses unveiled that PP microfibers (0.01-50 mg/L) from DMs impacted zebrafish larval swimming behavior, while PET microfibers from WMs delayed early-stage zebrafish hatching. This study offers new insights into the source of microfiber contamination and raises concerns about the environmental implications linked to the use of washable face masks.

Placental and fetal enrichment of microplastics from disposable paper cups: implications for metabolic and reproductive health during pregnancy

The disposable paper cups (DPCs) release millions of microplastics (MPs) when used for hot beverages. However, the tissue-specific deposition and toxic effects of MPs and associated toxins remain largely unexplored, especially at daily consumption levels. We administered MPs and associated toxins extracted from leading brand DPCs to pregnant mice, revealing dose-responsive harmful effects on fetal development and maternal physiology. MPs were detected in all 13 examined tissues, with preferred depositions in the fetus, placenta, kidney, spleen, lung, and heart, contributing to impaired phenotypes. Brain tissues had the smallest MPs (90.35 % < 10 µm). A dose-responsive shift in the cecal microbiome from Firmicutes to Bacteroidetes was observed, coupled with enhanced biosynthesis of microbial fatty acids. A moderate consumption of 3.3 cups daily was sufficient to alter the cecal microbiome, global metabolic functions, and immune health, as reflected by tissue-specific transcriptomic analyses in maternal blood, placenta, and mammary glands, leading to neurodegenerative and miscarriage risks. Gene-based benchmark dose framework analysis suggested a safe exposure limit of 2 to 4 cups/day in pregnant mice. Our results highlight tissue-specific accumulation and metabolic and reproductive toxicities in mice at DPC consumption levels presumed non-hazardous, with potential health implications for pregnant women and fetuses.

Adverse health effects of exposure to plastic, microplastics and their additives: environmental, legal and policy implications for Israel

BACKGROUND

Israel is a regional "hotspot" of plastic pollution, with little discussion of potential adverse health effects from exposure to plastic. This review aims to stimulate discussion and drive policy by focusing on these adverse health effects.

MAIN BODY

Plastics are synthetic polymers containing additives which can leach from food- and beverage-contact plastic into our food and beverages, and from plastic textiles onto our skin. Plastics persist in the environment for generations, fragmenting into MNPs: Micro (1 micron-5 mm)-Nano (1 nm-1 micron)-Plastic, which contaminate our atmosphere, water, and food chain. MNP can enter the human body through ingestion, inhalation and touch. MNP < 10 microns can cross epithelial barriers in the respiratory and gastrointestinal systems, and fragments < 100 nm can cross intact skin, enabling entry into body tissues. MNP have been found in multiple organs of the human body. Patients with MNP in atheromas of carotid arteries have increased risk of a combined measure of stroke, cardiovascular disease, and death. Toxic additives to plastics include bisphenols, phthalates, and PFAS, endocrine-disrupting chemicals (EDCs) which cause dysregulation of thyroid function, reproduction, and metabolism, including increased risk of obesity, diabetes, endometriosis, cancer, and decreased fertility, sperm count and quality. Fetal exposure to EDCs is associated with increased rates of miscarriages, prematurity and low birth weight. There is likely no safe level of exposure to EDCs, with increasing evidence of trans-generational and epigenetic effects. There are several existing Israeli laws to reduce plastic use and waste. Taxes on single-use plastic (SUP) were recently cancelled. There are many gaps in regulatory standards for food-, beverage- and child- safe plastic. Existing standards are poorly enforced.

CONCLUSION

Reduction in production and use of plastic, promotion of recycling and reduction of leaching of toxic additives into our food and beverages are essential policy goals. Specific recommendations: Periodic monitoring of MNP in bottled beverages, food, indoor air; Strengthen enforcement of standards for food-, beverage-, and child-safe plastic; Renew tax on SUPs; National ban on SUP at public beaches, nature reserves and parks; Ban products manufactured with MNP; Increase research on sources and health outcomes of exposure to MNP and EDCs.

Effects of microplastics on the kidneys: a narrative review

Microplastics (MPs) and nanoplastics are small synthetic organic polymer particles (<5 mm and <1 μm, respectively) that originate directly from plastic compounds or result from the degradation of plastic. These particles are a global concern because they are widely distributed in water, air, food, and soil, and recent scientific evidence has linked MPs to negative biological effects. Although these particles are difficult to detect in humans, MPs have been identified in different biological fluids and tissues, such as the placenta, lung, intestines, liver, blood, urine, and kidneys. Human exposure to MPs can occur by ingestion, inhalation, or dermal contact, potentially causing metabolic alterations. Data from experimental and clinical studies have revealed that the ability of MPs to promote inflammation, oxidative stress, and organ dysfunction and negatively affect clinical outcomes is associated with their accumulation in body fluids and tissues. Although evidence of the putative action of MPs in the human kidney is still scarce, there is growing interest in studying MPs in this organ. In addition, chronic kidney disease requires investigation because this condition is potentially prone to MP accumulation. The purpose of the present article is (i) to review the general aspects of MP generation, available analytic methods for identification, and the main known biological toxic effects; and (ii) to describe and critically analyze key experimental and clinical studies that support a role of MPs in kidney disease.

Plastic induced urinary tract disease and dysfunction: a scoping review

INTRODUCTION

In 2019 the World Health Organisation published a report which concluded microplastics in drinking water did not present a threat to human health. Since this time a plethora of research has emerged demonstrating the presence of plastic in various organ systems and their deleterious pathophysiological effects.

METHODS

A scoping review was undertaken in line with recommendations from the Johanna Briggs Institute. Five databases (PubMed, SCOPUS, CINAHL, Web of Science and EMBASE) were systematically searched in addition to a further grey literature search.

RESULTS

Eighteen articles were identified, six of which investigated and characterised the presence of microplastics and nanoplastics (MNPs) in the human urinary tract. Microplastics were found to be present in kidney, urine and bladder cancer samples. Twelve articles investigated the effect of MNPs on human cell lines associated with the human urinary tract. These articles suggest MNPs have a cytotoxic effect, increase inflammation, decrease cell viability and alter mitogen-activated protein kinases (MAPK) signalling pathways.

CONCLUSION

Given the reported presence MNPs in human tissues and organs, these plastics may have potential health implications in bladder disease and dysfunction. As a result, institutions such as the World Health Organisation need to urgently re-evaluate their position on the threat of microplastics to public health.

IMPACT STATEMENT

This scoping review highlights the rapidly emerging threat of microplastic contamination within the human urinary tract, challenging the World Health Organisation's assertion that microplastics pose no risk to public health. The documented cytotoxic effects of microplastics, alongside their ability to induce inflammation, reduce cell viability and disrupt signalling pathways, raise significant public health concerns relating to bladder cancer, chronic kidney disease, chronic urinary tract infections and incontinence. As a result, this study emphasises the pressing need for further research and policy development to address the challenges surrounding microplastic contamination.

Microplastics as a Threat to Aquatic Ecosystems and Human Health

The threat posed by microplastics has become one of the world's most serious problems. Recent reports indicate that the presence of microplastics has been documented not only in coastal areas and beaches, but also in water reservoirs, from which they enter the bodies of aquatic animals and humans. Microplastics can also bioaccumulate contaminants that lead to serious damage to aquatic ecosystems. The lack of comprehensive data makes it challenging to ascertain the potential consequences of acute and chronic exposure, particularly for future generations. It is crucial to acknowledge that there is still a substantial need for rapid and effective techniques to identify microplastic particles for precise evaluation. Additionally, implementing legal regulations, limiting plastic production, and developing biodegradation methods are promising solutions, the implementation of which could limit the spread of toxic microplastics.

Guardians under Siege: Exploring Pollution's Effects on Human Immunity

Chemical pollution poses a significant threat to human health, with detrimental effects on various physiological systems, including the respiratory, cardiovascular, mental, and perinatal domains. While the impact of pollution on these systems has been extensively studied, the intricate relationship between chemical pollution and immunity remains a critical area of investigation. The focus of this study is to elucidate the relationship between chemical pollution and human immunity. To accomplish this task, this study presents a comprehensive review that encompasses in vitro, ex vivo, and in vivo studies, shedding light on the ways in which chemical pollution can modulate human immunity. Our aim is to unveil the complex mechanisms by which environmental contaminants compromise the delicate balance of the body's defense systems going beyond the well-established associations with defense systems and delving into the less-explored link between chemical exposure and various immune disorders, adding urgency to our understanding of the underlying mechanisms and their implications for public health.

Health benefits and health risks of contaminated fish consumption: Current research outputs, research approaches, and perspectives

Background

Fish contains high-quality omega-3 fatty acids, protein, vitamins, and minerals and due to this it is termed as an essential component of a balanced diet. But there have been concerns raised about the risks of consuming fish that is contaminated with toxins such as methylmercury, polychlorinated biphenyls (PCBs), dioxins, pesticides, and plastic waste. Consumption of contaminated fish containing these pollutants is raising global mortality and morbidity rates.

Scope and approaches

The review examines the current research outputs on the health benefits and potential health risks of fish consumption. The review also discusses various approaches to mitigating the health problems caused by fish consumption, highlights the roles of balancing the risks and benefits when consuming fish.

Key findings and conclusion

Different findings indicated that contaminants cause cancer, kidney failure, adverse neurological effect, cardiovascular diseases, and so on to vulnerable groups such as pregnant, child breast-feeding and children. In conclusion, there is a need to get more tangible evidence about the advantages and disadvantages of fish consumption to safeguard the wellbeing of the society.