The emerging role of microplastics in systemic toxicity: Involvement of reactive oxygen species (ROS)

Toxicity study of mineral medicine haematitum

ETHNOPHARMACOLOGICAL RELEVANCE

Haematitum, a time-honored mineral-based Chinese medicine, has been used medicinally in China for over 2000 years. It is now included in the Chinese Pharmacopoeia and used clinically for treating digestive and respiratory diseases. The Chinese Materia Medica records that it is toxic and should not be taken for a long period, but there are few research reports on the toxicity of Haematitum and its potential toxicity mechanisms.

AIM OF THE STUDY

This study aimed to evaluate the toxicity of Haematitum and calcined Haematitum, including organ toxicity, neurotoxicity, and reproductive toxicity. Further, it is also necessary to explore the mechanism of Haematitum toxicity and to provide a reference for the safe clinical use of the drug.

MATERIALS AND METHODS

The samples of Haematitum and calcined Haematitum decoctions were prepared. KM mice were treated with samples by gavage for 10 days, and lung damage and apoptosis were assessed by HE staining and TUNEL staining of lung tissues respectively. Metabolomics analysis was performed by HPLC-MS. Metallomics analysis was performed by ICP-MS. In addition, C. elegans was used as a model for 48 h exposure to examine the neurotoxicity and reproductive toxicity-related indices of Haematitum, including locomotor behaviors, growth and development, reproductive behaviors, AChE activities, sensory behaviors, apoptosis, and ROS levels.

RESULTS

The use of large doses of Haematitum decoction caused lung damage in mice. Neither calcined Haematitum decoction nor Haematitum decoction at clinically used doses showed organ damage. Metabolomics results showed that disorders in lipid metabolic pathways such as sphingolipid metabolism and glycerophospholipid metabolism may be important factors in Haematitum-induced pulmonary toxicity. High doses of Haematitum decoction caused neurological damage to C. elegans, while low doses of Haematitum decoction and calcined Haematitum decoction showed no significant neurotoxicity. Decoction of Haematitum and calcined Haematitum did not show reproductive toxicity to C. elegans. Toxicity was also not observed in the control group of iron (Ⅱ) and iron (Ⅲ) ions in equal amounts with high doses of Haematitum.

CONCLUSIONS

Haematitum is relatively safe for routine doses and short-term use. Calcination can significantly reduce Haematitum toxicity, and this study provides a reference for safe clinical use.

Detection and analysis of microplastics in tissues and blood of human cervical cancer patients

Microplastics (MPs) can enter the reproductive system and can be potentially harmful to human reproductive health. In this study, 13 types of microplastics (MPs) were identified in patient blood, cancer samples, and paracarcinoma samples using Raman spectroscopy, with polyethylene, polypropylene and polyethylene-co-polypropylene being the most abundant polymer types. Futher, cotton was also found in our study. The diversity and abundance of MPs were higher in blood samples than in cancerous tissues, and there was a significant positive correlation between diversity (p < 0.05). Furthermore, the diversity and abundance of MPs in cancerous tissues were higher than in paracancerous tissues. The dimensional sizes of MPs in these samples were also very similar, with the majority of detected MPs being smaller in size. Correlation analysis showed that patient's age correlated with the abundance of MPs in blood samples, body mass index (BMI) correlated with the abundance of MPs in cancerous tissues. Notably, the frequency with which patients consume bottled water and beverages may also increase the abundance of MPs. This study identifies for the first time the presence of MPs and cotton in cancerous and paracancerous tissues of human cervical cancer patients. This provides new ideas and basic data to study the risk relationship between MP exposure and human health.

Raman-guided exploration of placental microplastic exposure: Unraveling the polymeric tapestry and assessing developmental implications

The prevalence of microplastics in human tissues and their potential reproductive toxicity have been increasingly documented, yet their appearance in the placenta and the impact of microplastic exposure on human fertility and pregnancy remains uncertain. Utilizing an inVia™ confocal Raman microspectroscopy by Renishaw equipped with a detection threshold as low as 0.25 µm, our study examined the microplastics in the placentas of 50 women post-delivery and investigated their correlations with gestational age, and neonatal length and weight. We found that 40 microplastic particles were identified across 31 of 50 placentas, averaging 2.35 ± 1.25 µm in size and ranging from 1.03 to 6.84 µm. Seven distinct polymer types were detected, with PTFE, PS, and ABS being the most prevalent. Notably, no significant difference across the normal, PTFE, and PS groups for all demographic variables examined was identified, nor as pathological alterations of placental tissues. In conclusion, our findings demonstrate the presence of seven microplastic polymers in human placentas, with PTFE, PS, and ABS being the most prevalent. However, maternal and neonatal parameters were not affected, and further studies are necessary to elucidate the effects of microplastics on developmental outcomes and fetal health.

Screening of optimal cleaning methods to reduce microplastic residues on strawberry surfaces: Characterization of microplastics in strawberry wash water

Microplastics are widespread in facility strawberry greenhouses and can be deposited on the surface of strawberries through air currents. Investigating effective cleaning methods represents a viable strategy to reduce human ingestion of MPs. Therefore, different cleaning methods were compared: ultrasonic cleaning for 30 min, deionized water rinsing once, deionized water immersion for 30 min, and fruit immersion in washing salt for 30 min. The MPs in strawberry washing water were analyzed and compared using laser direct infrared imaging to investigate their characteristics and the optimal reduction of MPs on the surface of strawberries. The quality of the cleaning results was in the following order: water immersion > washing salt immersion > water rinsing > ultrasound. Water immersion was 1.3-2 times more effective in removing microplastics than other treatments. Furthermore, 21 polymer types were detected in the samples. Most MPs were less than 50 µm in size. The main polymers in this size range were polyamide, chlorinated polyethylene, and polyethylene terephthalate, and they mainly existed as fragments, fibers, and beads. This study provides a valuable reference for reducing human intake of microplastics through fresh fruits and vegetables.

A review of the neurobehavioural, physiological, and reproductive toxicity of microplastics in fishes

Microplastics (MPs) have emerged as widespread environmental pollutants, causing significant threats to aquatic ecosystems and organisms. This review examines the toxic effects of MPs on fishes, with a focus on neurobehavioural, physiological, and reproductive impacts, as well as the underlying mechanisms of toxicity. Evidence indicates that MPs induce a range of neurobehavioural abnormalities in fishes, affecting social interactions and cognitive functions. Altered neurotransmitter levels are identified as a key mechanism driving behavioural alterations following MP exposure. Physiological abnormalities in fishes exposed to MPs are also reported, including neurotoxicity, immunotoxicity, and oxidative stress. These physiological disruptions can compromise the individual health of aquatic organisms. Furthermore, reproductive abnormalities linked to MP exposure are discussed, with a particular emphasis on disruptions in endocrine signaling pathways. These disruptions can impair reproductive success in fish species, impacting population numbers. Here we explore the critical role of endocrine disruptions in mediating reproductive effects after exposure to MPs, focusing primarily on the hypothalamic-pituitary-gonadal axis. Our review highlights the urgent need for interdisciplinary research efforts aimed at elucidating the full extent of MP toxicity and its implications for aquatic ecosystems. Lastly, we identify knowledge gaps for future research, including investigations into the transgenerational impacts, if any, of MP exposure and quantifying synergetic/antagonistic effects of MPs with other environmental pollutants. This expanded knowledge regarding the potential risks of MPs to aquatic wildlife is expected to aid policymakers in developing mitigation strategies to protect aquatic species.

Microplastics in marine ecosystems: A comprehensive review of biological and ecological implications and its mitigation approach using nanotechnology for the sustainable environment

Microplastic contamination has rapidly become a serious environmental issue, threatening marine ecosystems and human health. This review aims to not only understand the distribution, impacts, and transfer mechanisms of microplastic contamination but also to explore potential solutions for mitigating its widespread impact. This review encompasses the categorisation, origins, and worldwide prevalence of microplastics and methodically navigates the complicated structure of microplastics. Understanding the sources of minute plastic particles infiltrating water bodies worldwide is critical for successful removal. The presence and accumulation of microplastics has far reaching negative impacts on various marine creatures, eventually extending its implications to human health. Microplastics are known to affect the metabolic activities and the survival of microbial communities, phytoplankton, zooplankton, and fauna present in marine environments. Moreover, these microplastics cause developmental abnormalities, endocrine disruption, and several metabolic disorders in humans. These microplastics accumulates in aquatic environments through trophic transfer mechanisms and biomagnification, thereby disrupting the delicate balance of these ecosystems. The review also addresses the tactics for minimising the widespread impact of microplastics by suggesting practical alternatives. These include increasing public awareness, fostering international cooperation, developing novel cleanup solutions, and encouraging the use of environment-friendly materials. In conclusion, this review examines the sources and prevalence of microplastic contamination in marine environment, its impacts on living organisms and ecosystems. It also proposes various sustainable strategies to mitigate the problem of microplastics pollution. Also, the current challenges associated with the mitigation of these pollutants have been discussed and addressing these challenges require immediate and collective action for restoring the balance in marine ecosystems.

A systematic review on the impact of micro-nanoplastics on human health: Potential modulation of epigenetic mechanisms and identification of biomarkers

Epigenetic-mediated modifications, induced by adverse environmental conditions, significantly alter an organism's physiological mechanisms. Even after elimination of the stimulus, these epigenetic modifications can be inherited through mitosis, thereby triggering transgenerational epigenetics. Plastics, with their versatile properties, are indispensable in various aspects of daily life. However, due to mismanagement, plastics have become so ubiquitous in the environment that no ecosystem on Earth is free from micro-nanoplastics (MNPs). This situation has raised profound concerns regarding their potential impact on human health. Recently, both in vivo animal and in vitro human cellular models have shown the potential to identify the harmful effects of MNPs at the genome level. The emerging epigenetic impact of MNP exposure is characterized by short-term alterations in chromatin remodelling and miRNA modulation. However, to understand long-term epigenetic changes and potential transgenerational effects, substantial and more environmentally realistic exposure studies are needed. In the current review, the intricate epigenetic responses, including the NHL-2-EKL-1, NDK-1-KSR1/2, and WRT-3-ASP-2 cascades, wnt-signalling, and TGF- β signalling, established in model organisms such as C. elegans, mice, and human cell lines upon exposure to MNPs, were systematically examined. This comprehensive analysis aimed to predict human pathways by identifying human homologs using databases and algorithms. We are confident that various parallel miRNA pathways, specifically the KSR-ERK-MAPK pathway, FOXO-Insulin cascade, and GPX3-HIF-α in humans, may be influenced by MNP exposure. This influence may lead to disruptions in key metabolic and immune pathways, including glucose balance, apoptosis, cell proliferation, and angiogenesis. Therefore, we believe that these genes and pathways could serve as potential biomarkers for future studies. Additionally, this review emphasizes the origin, dispersion, and distribution of plastics, providing valuable insights into the complex relationship between plastics and human health while elaborating on the epigenetic impacts.

Organ-specific bioaccumulation of microplastics in market fish of Dhaka and size-dependent impacts of PVC microplastics on growth of Anabustestudineus

Microplastics (MPs), a growing environmental concern with potential ecotoxicological risks, are ubiquitous in aquatic environment. This study investigated the organ-specific distribution and variation of MPs in commercially caught fishes (7 species, 140 individuals) collected from Dhaka's two main fish distribution hubs (Uttara and Jatrabari). Additionally, the impact of different-sized MPs on fish growth (Anabas testudineus) was examined in a control experiment. Results revealed that kidneys of market fish bioaccumulated the highest concentration of MPs (average, 59.1 MPs/g), followed by liver (24.6 MPs/g) and intestine (18.6 MPs/g). On average, fish from Uttara had a higher MPs concentration (36 MPs/g) compared to Jatrabari (25 MPs/g). Among fish species, Glossogobius giuris showed the highest MPs bioaccumulation due to its feeding habits and morphology. Fiber-shaped MPs were most prevalent in all fishes (79-93%) except Glossogobius giuris (fragments, 51%). Fourier-transform infrared spectroscopy (FTIR) analysis identified 19 different polymer types, with high density polyethylene (HDPE), ethylene vinyl acetate (EVA) and polyamide (PA) being commonly found in all organs. The experimental study confirmed that large-sized PVC MPs (1.18 mm-300 μm) had a greater negative impact on fish growth (length) and caused more physical deformities (particularly intestinal injuries) compared to small-sized PVC MPs (150 μm-75 μm). Moreover, fish exposed to larger diameter MPs experienced highest physical weight and depth loss among exposed groups. Large-sized PVC MPs bioaccumulated highest in fish compared to small-sized PVC MPs. Similar to market fish, kidney in the experimental fish had the highest MPs bioaccumulation (6.5 MPs/g), followed by liver (5.2 MPs/g) and intestine (4.8 MPs/g), with a dominance of fibers despite the presence of high concentration of fragments in the food source. Statistical analysis also supported a clear correlation between increasing MPs size and adverse effects on fish growth and health. Urgent action is needed to curb microplastic pollution and protect ecosystems and human health.

Hazardous effects of plastic microfibres from facial masks to aquatic animal health: Insights from zebrafish model

Facial masks are a source of plastic microfibres (PMFs) in the aquatic environment, an emerging risk factor for aquatic organisms. However, little is known concerning its impact during the early developmental stages of fish. Thus, the current study aimed to evaluate the potential interaction and developmental toxicity of PMFs derived from leachate of surgical masks (SC-Msk) and N-95 facial masks (N95-Msk) using a multi-biomarker approach in developing zebrafish (Danio rerio). PMFs from both facial masks were obtained and characterized by multiple techniques. Zebrafish embryos were exposed to environmentally relevant concentrations of PMFs from both facial masks (1000, 10,000, and 100,000 particle L-1), and the toxicity was analysed in terms of mortality, hatching rate, neurotoxicity, cardiotoxicity, morphological changes, reactive oxygen species (ROS) levels, cell viability, and behavioural impairments. The results showed that both facial masks can release PMFs, but the N95-Msk produced a higher concentration of PMFs than SC-Msk. Both PMFs can interact with zebrafish chorion and don't cause effects on embryo mortality and hatching; however, zebrafish embryos showed cardiotoxic effects, and larvae showed increased agitation, average speed, and distance travelled, indicating the behavioural impairments induced by PMFs derived from facial masks. Overall, results showed the risk of PMFs to the health of freshwater fish, indicating the need for greater attention to the disposal and ecotoxicological effects of facial masks on aquatic organisms.

The role of gut microbiota in MP/NP-induced toxicity

Microplastics (MPs) and nanoplastics (NPs) are globally recognized as emerging environmental pollutants in various environmental media, posing potential threats to ecosystems and human health. MPs/NPs are unavoidably ingested by humans, mainly through contaminated food and drinks, impairing the gastrointestinal ecology and seriously impacting the human body. The specific role of gut microbiota in the gastrointestinal tract upon MP/NP exposure remains unknown. Given the importance of gut microbiota in metabolism, immunity, and homeostasis, this review aims to enhance our current understanding of the role of gut microbiota in MP/NP-induced toxicity. First, it discusses human exposure to MPs/NPs through the diet and MP/NP-induced adverse effects on the respiratory, digestive, neural, urinary, reproductive, and immune systems. Second, it elucidates the complex interactions between the gut microbiota and MPs/NPs. MPs/NPs can disrupt gut microbiota homeostasis, while the gut microbiota can degrade MPs/NPs. Third, it reveals the role of the gut microbiota in MP/NP-mediated systematic toxicity. MPs/NPs cause direct intestinal toxicity and indirect toxicity in other organs via regulating the gut-brain, gut-liver, and gut-lung axes. Finally, novel approaches such as dietary interventions, prebiotics, probiotics, polyphenols, engineered bacteria, microalgae, and micro/nanorobots are recommended to reduce MP/NP toxicity in humans. Overall, this review provides a theoretical basis for targeting the gut microbiota to study MP/NP toxicity and develop novel strategies for its mitigation.

Moldable Plastics (Polycaprolactone) can be Acutely Toxic to Developing Zebrafish and Activate Nuclear Receptors in Mammalian Cells

Popularized on social media, hand-moldable plastics are formed by consumers into tools, trinkets, and dental prosthetics. Despite the anticipated dermal and oral contact, manufacturers share little information with consumers about these materials, which are typically sold as microplastic-sized resin pellets. Inherent to their function, moldable plastics pose a risk of dermal and oral exposure to unknown leachable substances. We analyzed 12 moldable plastics advertised for modeling and dental applications and determined them to be polycaprolactone (PCL) or thermoplastic polyurethane (TPU). The bioactivities of the most popular brands advertised for modeling applications of each type of polymer were evaluated using a zebrafish embryo bioassay. While water-borne exposure to the TPU pellets did not affect the targeted developmental end points at any concentration tested, the PCL pellets were acutely toxic above 1 pellet/mL. The aqueous leachates of the PCL pellets demonstrated similar toxicity. Methanolic extracts from the PCL pellets were assayed for their bioactivity using the Attagene FACTORIAL platform. Of the 69 measured end points, the extracts activated nuclear receptors and transcription factors for xenobiotic metabolism (pregnane X receptor, PXR), lipid metabolism (peroxisome proliferator-activated receptor γ, PPARγ), and oxidative stress (nuclear factor erythroid 2-related factor 2, NRF2). By nontargeted high-resolution comprehensive two-dimensional gas chromatography (GC × GC-HRT), we tentatively identified several compounds in the methanolic extracts, including PCL oligomers, a phenolic antioxidant, and residues of suspected antihydrolysis and cross-linking additives. In a follow-up zebrafish embryo bioassay, because of its stated high purity, biomedical grade PCL was tested to mitigate any confounding effects due to chemical additives in the PCL pellets; it elicited comparable acute toxicity. From these orthogonal and complementary experiments, we suggest that the toxicity was due to oligomers and nanoplastics released from the PCL rather than chemical additives. These results challenge the perceived and assumed inertness of plastics and highlight their multiple sources of toxicity.

Size-dependent effects of microplastics on intestinal microbiome for Perna viridis

Microplastics pollution threatens to marine organisms, particularly bivalves that actively ingest and accumulate microplastics of certain sizes, potentially disrupting intestinal homeostasis. This study investigated the microplastic abundance in wild and farmed mussels around Singapore, and examined the size-dependent effects of nano- to micro-scale polystyrene (0.5 µm/5 µm/50 µm) on the mussel intestinal microbiome in the laboratory. The field investigation revealed higher microplastic abundance in farmed mussels compared to wild ones. Experimentally, mussels exposed to 0.6 mg/L of microplastics for 7 days, followed by a 7-day depuration period, showed substantial impacts on Spirochaetes and Proteobacteria, facilitating the proliferation of pathogenic species and differentially affecting their pathogenic contributions. Metagenomics analysis revealed that microplastic exposure reduced Spirochaeta's contribution to virulence and pathogenicity loss, did not affect Vibrio and Oceanispirochaeta's pathogenicity, and increased Treponema and Oceanispirochaeta's contributions to pathogenicity loss. Moreover, microplastics increased transmembrane transporters and impacted oxidative phosphorylation enzymes, impairing energy metabolism. These effects persisted after depuration, indicating lack of resilience in the microbiome. Nano- and micro-scale plastics perturbed the mussel microbiome composition and functions in a size-dependent manner, with nano-plastics being the most disruptive. The increasing use and sale of aquaculture equipment of plastic may exacerbate the intestinal dysbiosis in bivalves, which threatens consumers' health.

Nano/micro-plastic, an invisible threat getting into the brain

Due to weather and working/operational conditions, plastic degradation produces toxic and non-biodegradable nano and microplastics (N/M-Ps, ranging from 10 nm to 5 mm), and over time these N/M-Ps have integrated with the human cycle through ingestion and inhalation. These N/M-Ps, as serious emerging pollutants, are causing considerable adverse health issues due to up-taken by the cells, tissue, and organs, including the brain. It has been proven that N/M-Ps can cross the blood-brain barrier (via olfactory and blood vessels) and affect the secretion of neuroinflammatory (cytokine and chemokine), transporters, and receptor markers. Neurotoxicity, neuroinflammation, and brain injury, which may result in such scenarios are a serious concern and may cause brain disorders. However, the related pathways and pathogenesis are not well-explored but are the focus of upcoming emerging research. Therefore, as a focus of this editorial, well-organized multidisciplinary research is required to explore associated pathways and pathogenesis, leading to brain mapping and nano-enabled therapeutics in acute and chronic N/M - Ps exposure.

Insights into the combined toxicity and mechanisms of BDE-47 and PFOA in marine blue mussel: An integrated study at the physiochemical and molecular levels

The coexistence of multiple emerging contaminants imposes a substantial burden on the ecophysiological functions in organisms. The combined toxicity and underlying mechanism requires in-depth understanding. Here, marine blue mussel (Mytilus galloprovincialis L.) was selected and exposed to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and perfluorooctanoic acid (PFOA) individually and in combination at environmental related concentrations to elucidate differences in stress responses and potential toxicological mechanisms. Characterization and comparison of accumulation, biomarkers, histopathology, transcriptomics and metabolomics were performed. Co-exposure resulted in differential accumulation patterns, exacerbated histopathological alterations, and different responses in oxidative stress and biomarkers for xenobiotic transportation. Moreover, the identified differentially expressed genes (DEGs) and differential metabolites (DEMs) in mussels were found to be annotated to different metabolic pathways. Correlation analyses further indicated that DEGs and DEMs were significantly correlated with the above biomarkers. BDE-47 and PFOA altered the genes and metabolites related to amino acid metabolism, energy and purine metabolism, ABC transporters, and glutathione metabolism to varying degrees, subsequently inducing accumulation differences and combined toxicity. Furthermore, the present work highlighted the pivotal role of Nrf2-keap1 detoxification pathway in the acclimation of M. galloprovincialis to reactive oxygen species (ROS) stress induced by BDE-47 and PFOA. This study enabled more comprehensive understanding of combined toxic mechanism of multi emerging contaminants pollution.

Microplastic accumulation and oxidative stress in sweet pepper (Capsicum annuum Linn.): Role of the size effect

Microplastics (MPs), which are widely dispersed in terrestrial environments, threaten crop growth and human food security. However, plant accumulation and phytotoxicity related to the size effects of MPs remain insufficiently explored. This study investigated the accumulation and toxicity of two sizes of MPs on Capsicum annuum Linn. (C. annuum) through fluorescence tracing and antioxidant defense system assessment. The results revealed that the size of MPs significantly impacts their accumulation characteristics in C. annuum roots, leading to variations in toxic mechanisms, including oxidative stress and damage. Smaller MPs and higher exposure concentrations result in more pronounced growth inhibition. C. annuum roots have a critical size threshold for the absorption of MPs of approximately 1.2 μm. MPs that enter the root tissue exhibit an aggregated form, with smaller-sized MPs displaying a greater degree of aggregation. MP exposure induces oxidative stress in root tissues, with high concentrations of smaller MPs causing lipid peroxidation. Analysis of the IBR values revealed that C. annuum roots utilize ascorbic acid (ASA) to prevent oxidative damage caused by larger MPs. Conversely, smaller MPs primarily induce superoxide dismutase (SOD) and glutathione (GSH). These results emphasize the significant impact of MP size on plant antioxidant defense response mechanisms, laying the foundation for further investigating the implications for human health.

Oxidation enhances the toxicity of polyethylene microplastics to mouse eye: Perspective from in vitro and in vivo

Microplastics (MPs) are ubiquitously dispersed in the environment, and undergoing the process of oxidation that alters their physical and chemical properties. Eyes, which directly interface with the external milieu, inevitably encounter MPs. Nonetheless, the ophthalmic toxicity of MPs towards organisms remains unclear. In this study, primary mouse corneal epithelial cells (MCECs), C57BL/6 mice, and CX3CrlGFP/+ mice were utilized to evaluate the toxicity and differences between oxidized low-density polyethylene MPs (modified-MPs) and low-density polyethylene MPs (virgin-MPs) on eyes. The results manifested that virgin-MPs and modified-MPs could be endocytosed by primary MCECs, resulting in a range of cellular damage. Furthermore, they could diminish tear secretion, increase intraocular pressure, and could be internalized into cornea and retina in mice, instigating a series of detrimental reactions. Importantly, modified-MPs exhibited heightened toxicity towards mouse eyes, seemingly due to oxidation enhances the interaction between virgin-MPs/modified-MPs and tissues/cells, and leading to the release of toxic substances increased. In conclusion, our discoveries demonstrate that oxidation exacerbates the harm of virgin-MPs to eyes, and are of great significance for evaluating the risk of MPs to ocular health.

Polystyrene nanoplastics exposure causes erectile dysfunction in rats

Polystyrene nanoplastics (PS-NPs), emerging and increasingly pervasive environmental contaminants, have the potential to cause persistent harm to organisms. Although previous reports have documented local accumulation and adverse effects in a variety of major organs after PS-NPs exposure, the impact of PS-NPs exposure on erectile function remains unexplored. Herein, we established a rat model of oral exposure to 100 nm PS-NPs for 28 days. To determine the best dose range of PS-NPs, we designed both low-dose and high-dose PS-NPs groups, which correspond to the minimum and maximum human intake doses, respectively. The findings indicated that PS-NPs could accumulate within the corpus cavernosum and high dose but not low dose of PS-NPs triggered erectile dysfunction. Moreover, the toxicological effects of PS-NPs on erectile function include fibrosis in the corpus cavernous, endothelial dysfunction, reduction in testosterone levels, elevated oxidative stress and apoptosis. Overall, this study revealed that PS-NPs exposure can cause erectile dysfunction via multiple ways, which provided new insights into the toxicity of PS-NPs.

The generation and transformation mechanisms of reactive oxygen species in the environment and their implications for pollution control processes: A review

Reactive oxygen species (ROS), substances with strong activity generated by oxygen during electron transfer, play a significant role in the decomposition of organic matter in various environmental settings, including soil, water and atmosphere. Although ROS has a short lifespan (ranging from a few nanoseconds to a few days), it continuously generated during the interaction between microorganisms and their environment, especially in environments characterized by strong ultraviolet radiation, fluctuating oxygen concentration or redox conditions, and the abundance of metal minerals. A comprehensive understanding of the fate of ROS in nature can provide new ideas for pollutant degradation and is of great significance for the development of green degradation technologies for organic pollutants. At present, the review of ROS generally revolves around various advanced oxidation processes, but lacks a description and summary of the fate of ROS in nature, this article starts with the definition of reactive oxidants species and reviews the production, migration, and transformation mechanisms of ROS in soil, water and atmospheric environments, focusing on recent developments. In addition, the stimulating effects of ROS on organisms were reviewed. Conclusively, the article summarizes the classic processes, possible improvements, and future directions for ROS-mediated degradation of pollutants. This review offers suggestions for future research directions in this field and provides the possible ROS technology application in pollutants treatment.

Kinetics and toxicity of nanoplastics in ex vivo exposed human whole blood as a model to understand their impact on human health

The ubiquitous presence of nanoplastics (NPLs) in the environment is considered of great health concern. Due to their size, NPLs can cross both the intestinal and pulmonary barriers and, consequently, their presence in the blood compartment is expected. Understanding the interactions between NPLs and human blood components is required. In this study, to simulate more adequate real exposure conditions, the whole blood of healthy donors was exposed to five different NPLs: three polystyrene NPLs of approximately 50 nm (aminated PS-NH2, carboxylated PS-COOH, and pristine PS- forms), together with two true-to-life NPLs from polyethylene terephthalate (PET) and polylactic acid (PLA) of about 150 nm. Internalization was determined in white blood cells (WBCs) by confocal microscopy, once the different main cell subtypes (monocytes, polymorphonucleated cells, and lymphocytes) were sorted by flow cytometry. Intracellular reactive oxygen species (iROS) induction was determined in WBCs and cytokine release in plasma. In addition, hemolysis, coagulation, and platelet activation were also determined. Results showed a differential uptake between WBC subtypes, with monocytes showing a higher internalization. Regarding iROS, lymphocytes were those with higher levels, which was observed for different NPLs. Changes in cytokine release were also detected, with higher effects observed after PLA- and PS-NH2-NPL exposure. Hemolysis induction was observed after PS- and PS-COOH-NPL exposure, but no effects on platelet functionality were observed after any of the treatments. To our knowledge, this is the first study comprehensively evaluating the bloodstream kinetics and toxicity of NPL from different polymeric types on human whole blood, considering the role played by the cell subtype and the NPLs physicochemical characteristics in the effects observed after the exposures.

Impact of polystyrene nanoplastics on apoptosis and inflammation in zebrafish larvae: Insights from reactive oxygen species perspective

In recent years, there has been a growing focus on the toxicity and mortality induced by nanoplastics (NPs) in aquatic organisms. However, studies investigating mechanisms underlying oxidative stress (OS), apoptosis, and inflammation induced by NPs in fish remain limited. This study observed that polystyrene NPs (PS-NPs) were accumulated into zebrafish larvae and zebrafish embryonic fibroblast (ZF4 cells), accompanied by the occurrence of pathological damage both at the cellular and tissue-organ level. Additionally, the transcriptional up-regulation of NADPH oxidases (NOXs) and subsequent excessive generation of reactive oxygen species (ROS) resulted in notable changes in the relative mRNA and protein expression levels associated with antioxidant oxidase systems in larvae. Furthermore, the study identified the impact of NPs on mitochondrial ultrastructural, resulting in mitochondrial depolarization and downregulation of mRNA expression related to the electron transport chain due to excessive ROS generation. Short-term exposure to NPs also triggered apoptosis and inflammation in zebrafish larvae, evident from significant up-regulation in mRNA expressions of proapoptotic factors and NF-κB proinflammatory signaling pathway, as well as increased transcription and protein levels of pro-inflammatory factors in larvae. Inhibition of intracellular excessive ROS effectively reduced the induction of apoptosis, NF-κB P65 nuclear migration levels, and cytokine secretion, underscoring OS as a pivotal factor throughout the process of apoptosis and inflammatory responses induced by NPs. This research significantly advances our comprehension of biological effects and underlying mechanisms of NPs in freshwater fish.

Exploring developmental toxicity of microplastics and nanoplastics (MNPS): Insights from investigations using zebrafish embryos

Microplastics and nanoplastics (MNPs) have received increasing attention due to their high detection rates in human matrices and adverse health implications. However, the toxicity of MNPs on embryo/fetal development following maternal exposure remains largely unexplored. Zebrafish, sharing genetic similarities with human, boast a shorter life cycle, rapid embryonic development, and the availability of many transgenic strains, is a suitable model for environmental toxicology studies. This review comprehensively explores the existing research on the impacts of MNPs on zebrafish embryo development. MNPs exposure induces a wide array of toxic effects, encompassing neurodevelopmental toxicity, immunotoxicity, gastrointestinal effects, microbiota dysbiosis, cardiac dysfunctions, vascular toxicity, and metabolic imbalances. Moreover, MNPs disrupt the balance between reactive oxygen species (ROS) production and antioxidant capacity, culminating in oxidative damage and apoptosis. This study also offers insight into the current omics- and multi-omics based approaches in MNPs research, which greatly expedite the discovery of biochemical or metabolic pathways, and molecular mechanisms underlying MNPs exposure. Additionally, this review proposes a preliminary adverse outcome pathway framework to predict developmental toxicity caused by MNPs. It provides a comprehensive overview of pathways, facilitating a clearer understanding of the exposure and toxicity of MNPs, from molecular effects to adverse outcomes. The compiled data in this review provide a better understanding for MNPs effects on early life development, with the goal of increasing awareness about the risks posed to pregnant women by MNPs exposure and its potential impact on the health of their future generations.

Mangrove mud clam as an effective sentinel species for monitoring changes in coastal microplastic pollution

The worldwide mangrove shorelines are experiencing considerable contamination from microplastics (MPs). Finding an effective sentinel species in the mangrove ecosystem is crucial for early warning of ecological and human health risks posed by coastal microplastic pollution. This study collected 186 specimens of the widely distributed mangrove clam (Geloina expansa, Solander, 1786) from 18 stations along the Leizhou Peninsula, the largest mangrove coast in Southern China. This study discovered that mangrove mud clams accumulated a relatively high abundance of MPs (2.96 [1.61 - 6.03] items·g-1) in their soft tissue, wet weight, as compared to previously reported levels in bivalves. MPs abundance is significantly (p < 0.05 or 0.0001) influenced by coastal urban development, aquaculture, and shell size. Furthermore, the aggregated MPs exhibit a significantly high polymer risk index (Level III, H = 353.83). The estimated annual intake risk (EAI) from resident consumption, as calculated via a specific questionnaire survey, was at a moderate level (990 - 2475, items·g -1·Capita -1). However, the EAI based on suggested nutritional standards is very high, reaching 113,990 (79,298 - 148,681), items·g -1·Capita -1. We recommend utilizing the mangrove mud clam as sentinel species for the monitoring of MPs pollution changing across global coastlines.

Nanoplastics induced health risk: Insights into intestinal barrier homeostasis and potential remediation strategy by dietary intervention

Aged nanoplastics (aged-NPs) have unique characteristics endowed by environmental actions, such as rough surface, high oxygen content. Although studies have highlighted the potential hazards of aged-NPs, limited research has provided strategies for aged-NPs pollution remediation. The dietary intervention of quercetin is a novel insight to address the health risks of aged-NPs. This study explored the impact of aged-NPs on intestinal barrier homeostasis at the environmentally relevant dose and investigated the alleviating effects of quercetin on aged-NPs toxicity through transcriptomics and molecular biology analysis. It indicated that aged-NPs induced intestinal barrier dysfunction, which was characterized by higher permeability, increased inflammation, and loss of epithelial integrity, while quercetin restored it. Aged-NPs disrupted redox homeostasis, upregulated inflammatory genes controlled by AP-1, and led to Bax-dependent mitochondrial apoptosis. Quercetin intervention effectively mitigated inflammation and apoptosis by activating the Nrf2. Thus, quercetin decreased intestinal free radical levels, inhibiting the phosphorylation of p38 and JNK. This study unveiled the harmful effects of aged-NPs on intestinal homeostasis and the practicability of dietary intervention against aged-NPs toxicity. These findings broaden the understanding of the NPs toxicity and provide an effective dietary strategy to relieve the health risks of NPs. ENVIRONMENTAL IMPLICATIONS: Growing levels of NPs pollution have represented severe health hazards to the population. This study focuses on the toxic mechanism of aged-NPs on the intestinal barrier and the alleviating effect of quercetin dietary intervention, which considers the environmental action and relevant dose. It revealed the harmful effects of aged-NPs on intestinal inflammation with the key point of free radical generation. Furthermore, a quercetin-rich diet holds significant promise for addressing and reversing intestinal damage caused by aged-NPs by maintaining intracellular redox homeostasis. These findings provide an effective dietary strategy to remediate human health risks caused by NPs.

Research Progress on Micro(nano)plastic-Induced Programmed Cell Death Associated with Disease Risks

Due to their robust migration capabilities, slow degradation, and propensity for adsorbing environmental pollutants, micro(nano)plastics (MNPs) are pervasive across diverse ecosystems. They infiltrate various organisms within different food chains through multiple pathways including inhalation and dermal contact, and pose a significant environmental challenge in the 21st century. Research indicates that MNPs pose health threats to a broad range of organisms, including humans. Currently, extensive detection data and studies using experimental animals and in vitro cell culture indicate that MNPs can trigger various forms of programmed cell death (PCD) and can induce various diseases. This review provides a comprehensive and systematic analysis of different MNP-induced PCD processes, including pyroptosis, ferroptosis, autophagy, necroptosis, and apoptosis, based on recent research findings and focuses on elucidating the links between PCD and diseases. Additionally, targeted therapeutic interventions for these diseases are described. This review provides original insights into the opportunities and challenges posed by current research findings. This review evaluates ways to mitigate various diseases resulting from cell death patterns. Moreover, this paper enhances the understanding of the biohazards associated with MNPs by providing a systematic reference for subsequent toxicological research and health risk mitigation efforts.

Effects of microplastics and combined pollution of polystyrene and di-n-octyl phthalate on photosynthesis of cucumber (Cucumis sativus L.)

Photosynthesis provides carbon sources and energy for crop growth and development, and the widespread presence of microplastics and plastic plasticisers in agricultural soils affects crop photosynthesis, but the mechanism of the effect is not clear. This study aims to investigate the effects of different microplastics and plasticizers on cucumber photosynthesis. Using polyvinyl chloride (PVC), polyethylene (PE), polystyrene (PS), and di-n-octyl phthalate (DOP) as representative microplastics and plasticizers, we assessed their impact on cucumber photosynthesis. Our results reveal significant alterations in key parameters: intercellular CO2 concentration (Ci) and transpiration rate (Tr) increased across all treatments, whereas stomatal limit value (Ls) and water use efficiency (WUE) decreased. Notably, PS + DOP treatment led to a significant reduction in the maximum efficiency of photosystem II (Fv/Fm) and ATP accumulation. Furthermore, PE and PS + DOP treatments decreased lycopene and ɛ-carotene synthesis rates, as well as abscisic acid (ABA) accumulation. All treatments inhibited the conversion of β-carotene into strigolactone (SL) and decreased chlorophyll synthesis rates, with PS + DOP exhibiting the most severe impact. Regarding chlorophyll degradation pathways, PVC and PE treatments reduced chlorophyll decomposition rates, whereas DOP with PS promoted degradation. PE and PS treatments also impaired light energy capture, electron transport, and the structural stability of photosystems I and II, as well as photosynthetic capacity and NADPH and ATP synthesis rates. Our findings underscore the differential impacts of microplastics and plasticizers on cucumber photosynthesis, with PS + DOP having the most detrimental effect. These results shed light on the complex interactions between microplastics and plant physiology, highlighting the urgent need for mitigation strategies in agricultural practices to safeguard crop productivity and environmental sustainability.

Atlantic salmon gill epithelial cell line ASG-10, an in vitro model for studying effects of microplastics in gills

Microplastics are ubiquitous environmental pollutants frequently detected in aquatic environments. Here we used the Atlantic salmon epithelial gill cell line (ASG-10) to investigate the uptake and effects of polystyrene (PS) microplastic. The ASG-10 cell line has phagocytotic/endocytic capacities and can take up clear PS particles at 0.2 and 1.0 µm, while PS at 10 µm was not taken up. As a response to the uptake, the ASG-10 cells increased their lysosomal activity. Furthermore, no effects on the mitochondria were found, neither on the mitochondrial membrane potential nor the mitochondria morphology (branch length and diameter). Interestingly, even a very high concentration of PS (200 µg/ml) with all tested particle sizes had no effects on cell viability or cell cycle. The environmental toxin Benzo(a)pyrene (B(a)P), a known inducer of CYP1A, is highly hydrophobic and thus sticks to the PS particles. However, co-exposure of B(a)P and PS the particles did not increase the induction of CYP1A activity compared to B(a)P alone. Our study contributes to the understanding of the cellular effects of PS particles using a highly relevant Atlantic salmon gill epithelium in vitro model.

Insight into effect of polyethylene microplastic on nitrogen removal in moving bed biofilm reactor: Focusing on microbial community and species interactions

Microplastics (MPs) pollution has emerged as a global concern, and wastewater treatment plants (WWTPs) are one of the potential sources of MPs in the environment. However, the effect of polyethylene MPs (PE) on nitrogen (N) removal in moving bed biofilm reactor (MBBR) remains unclear. We hypothesized that PE would affect N removal in MBBR by influencing its microbial community. In this study, we investigated the impacts of different PE concentrations (100, 500, and 1000 μg/L) on N removal, enzyme activities, and microbial community in MBBR. Folin-phenol and anthrone colorimetric methods, oxidative stress and enzyme activity tests, and high-throughput sequencing combined with bioinformation analysis were used to decipher the potential mechanisms. The results demonstrated that 1000 μg/L PE had the greatest effect on NH4+-N and TN removal, with a decrease of 33.5 % and 35.2 %, and nitrifying and denitrifying enzyme activities were restrained by 29.5-39.6 % and 24.6-47.4 %. Polysaccharide and protein contents were enhanced by PE, except for 1000 μg/L PE, which decreased protein content by 65.4 mg/g VSS. The positive links of species interactions under 1000 μg/L PE exposure was 52.07 %, higher than under 500 μg/L (51.05 %) and 100 μg/L PE (50.35 %). Relative abundance of some metabolism pathways like carbohydrate metabolism and energy metabolism were restrained by 0.07-0.11 % and 0.27-0.4 %. Moreover, the total abundance of nitrification and denitrification genes both decreased under PE exposure. Overall, PE reduced N removal by affecting microbial community structure and species interactions, inhibiting some key metabolic pathways, and suppressing key enzyme activity and functional gene abundance. This paper provides new insights into assessing the risk of MPs to WWTPs, contributing to ensuring the health of aquatic ecosystems.

Exposure to polystyrene nanoplastics induces hepatotoxicity involving NRF2-NLRP3 signaling pathway in mice

Nanoplastic contamination has been of intense concern by virtue of the potential threat to human and ecosystem health. Animal experiments have indicated that exposure to nanoplastics (NPs) can deposit in the liver and contribute to hepatic injury. To explore the mechanisms of hepatotoxicity induced by polystyrene-NPs (PS-NPs), mice and AML-12 hepatocytes were exposed to different dosages of 20 nm PS-NPs in this study. The results illustrated that in vitro and in vivo exposure to PS-NPs triggered excessive production of reactive oxygen species and repressed nuclear factor erythroid-derived 2-like 2 (NRF2) antioxidant pathway and its downstream antioxidase expression, thus leading to hepatic oxidative stress. Moreover, PS-NPs elevated the levels of NLRP3, IL-1β and caspase-1 expression, along with an activation of NF-κB, suggesting that PS-NPs induced hepatocellular inflammatory injury. Nevertheless, the activaton of NRF2 signaling by tert-butylhydroquinone mitigated PS-NPs-caused oxidative stress and inflammation, and inbihited NLRP3 and caspase-1 expression. Conversely, the rescuing effect of NRF2 signal activation was dramatically supressed by treatment with NRF2 inhibitor brusatol. In summary, our results demonstrated that NRF2-NLRP3 pathway is involved in PS-NPs-aroused hepatotoxicity, and the activation of NRF2 signaling can protect against PS-NPs-evoked liver injury. These results provide novel insights into the hepatotoxicity elicited by NPs exposure.

Toxicological review of micro- and nano-plastics in aquatic environments: Risks to ecosystems, food web dynamics and human health

The increase of micro- and nano-plastics (MNPs) in aquatic environments has become a significant concern due to their potential toxicological effects on ecosystems, food web dynamics, and human health. These plastic particles emerge from a range of sources, such as the breakdown of larger plastic waste, consumer products, and industrial outputs. This review provides a detailed report of the transmission and dangers of MNPs in aquatic ecosystems, environmental behavior, and interactions within aquatic food webs, emphasizing their toxic impact on marine life. It explores the relationship between particle size and toxicity, their distribution in different tissues, and the process of trophic transfer through the food web. MNPs, once consumed, can be found in various organs, including the digestive system, gills, and liver. Their consumption by lower trophic level organisms facilitates their progression up the food chain, potentially leading to bioaccumulation and biomagnification, thereby posing substantial risks to the health, reproduction, and behavior of aquatic species. This work also explores how MNPs, through their persistence and bioaccumulation, pose risks to aquatic biodiversity and disrupt trophic relationships. The review also addresses the implications of MNPs for human health, particularly through the consumption of contaminated seafood, highlighting the direct and indirect pathways through which humans are exposed to these pollutants. Furthermore, the review highlights the recommendations for future research directions, emphasizing the integration of ecological, toxicological, and human health studies to inform risk assessments and develop mitigation strategies to address the global challenge of plastic pollution in aquatic environments.

Microplastics and environmental effects: investigating the effects of microplastics on aquatic habitats and their impact on human health

Microplastics (MPs) are particles with a diameter of <5 mm. The disposal of plastic waste into the environment poses a significant and pressing issue concern globally. Growing worry has been expressed in recent years over the impact of MPs on both human health and the entire natural ecosystem. MPs impact the feeding and digestive capabilities of marine organisms, as well as hinder the development of plant roots and leaves. Numerous studies have shown that the majority of individuals consume substantial quantities of MPs either through their dietary intake or by inhaling them. MPs have been identified in various human biological samples, such as lungs, stool, placenta, sputum, breast milk, liver, and blood. MPs can cause various illnesses in humans, depending on how they enter the body. Healthy and sustainable ecosystems depend on the proper functioning of microbiota, however, MPs disrupt the balance of microbiota. Also, due to their high surface area compared to their volume and chemical characteristics, MPs act as pollutant absorbers in different environments. Multiple policies and initiatives exist at both the domestic and global levels to mitigate pollution caused by MPs. Various techniques are currently employed to remove MPs, such as biodegradation, filtration systems, incineration, landfill disposal, and recycling, among others. In this review, we will discuss the sources and types of MPs, the presence of MPs in different environments and food, the impact of MPs on human health and microbiota, mechanisms of pollutant adsorption on MPs, and the methods of removing MPs with algae and microbes.

Effect of micro- and nanoplastic particles on human macrophages

Micro- and nanoplastics (MNPs) are ubiquitous in the environment, resulting in the uptake of MNPs by a variety of organisms, including humans, leading to particle-cell interaction. Human macrophages derived from THP-1 cell lines take up Polystyrene (PS), a widespread plastic. The question therefore arises whether primary human macrophages also take up PS micro- and nanobeads (MNBs) and how they react to this stimulation. Major aim of this study is to visualize this uptake and to validate the isolation of macrophages from peripheral blood mononuclear cells (PBMCs) to assess the impact of MNPs on human macrophages. Uptake of macrophages from THP-1 cell lines and PBMCs was examined by transmission electron microscopy (TEM), scanning electron microscopy and live cell imaging. In addition, the reaction of the macrophages was analyzed in terms of metabolic activity, cytotoxicity, production of reactive oxygen species (ROS) and macrophage polarization. This study is the first to visualize PS MNBs in primary human cells using TEM and live cell imaging. Metabolic activity was size- and concentration-dependent, necrosis and ROS were increased. The methods demonstrated in this study outline an approach to assess the influence of MNP exposure on human macrophages and help investigating the consequences of worldwide plastic pollution.

New insights into the spleen injury by mitochondrial dysfunction of chicken under polystyrene microplastics stress

Microplastics biological toxicity, environmental persistence and biological chemicals have been paid widespread attention. Microplastics exposed to chicken spleen injury of the specific mechanism is unclear. Thus, we randomly assigned chickens to 4 groups: C (normal diet), L-MPs (1 mg/L), M-MPs (10 mg/L), and H-MPs (100 mg/L), and assessed spleen damage after 42 d of exposure. Morphologically, the boundary between the red and white pulp of the spleen was blurred, along with the expansion of the white pulp. It was further speculated that microplastics induced mitochondrial dynamic homeostasis (Drp1 upgraded, Mfn1, Mfn2, and OPA1 reduced), and provoked the mitochondrial apoptotic pathway (Bcl-2/Bax decreased, cytc, caspase3, and caspase9 raised), resulting in redox imbalance and lipid peroxide accumulation (MDA increased, CAT, GSH, and T-AOC plummeted), and further stimulated ferroptosis (FTH1, GPX4, and SLC7A11 decreased). Here we explored the impact of polystyrene microplastics on the spleen, as well as the programmed death (apoptosis and ferroptosis) involved, and the regulative role of mitochondria in this process. This could be of significant importance in bridging the gap in laboratory research on microplastics-induced spleen injury in chicken.

Investigation of the effects of nanoplastic polyethylene terephthalate on environmental toxicology using model Drosophila melanogaster

Plastic pollution has become a major environmental concern, and various plastic polymers are used daily. A study was conducted to examine the toxic effects of polyethylene terephthalate (PET) nanoplastics (NPLs) on Drosophila melanogaster. We have successfully synthesized PET NPLs and characterized using DLS, Zeta potential, TEM, HRTEM, SAED, XRD, FTIR, and Raman spectroscopy to gain crucial insights into the structure and properties. We fed PET NPLs to Drosophila to assess toxicity. ROS was quantified using DCFH-DA and NBT, and the nuclear degradation was checked by DAPI staining. Quantification of protein and activity of antioxidant enzymes like SOD, catalase depicted the adverse consequences of PET NPLs exposure. The dorsal side of the abdomens, eyes, and wings were also defective when phenotypically analyzed. These results substantiate the genotoxic and cytotoxic impact of nanoplastics. Notably, behavioral observations encompassing larval crawling and climbing of adults exhibit normal patterns, excluding the presence of neurotoxicity. Adult Drosophila showed decreased survivability, and fat accumulation enhanced body weight. These findings contribute to unraveling the intricate mechanisms underlying nanoplastic toxicity and emphasize its potential repercussions for organismal health and ecological equilibrium.

A systematic review of microplastics emissions in kitchens: Understanding the links with diseases in daily life

The intensification of microplastics (MPs) pollution has emerged as a formidable environmental challenge, with profound global implications. The pervasive presence of MPs across a multitude of environmental mediums, such as the atmosphere, soil, and oceans, extends to commonplace items, culminating in widespread human ingestion and accumulation via channels like food, water, and air. In the domestic realm, kitchens have become significant epicenters for MPs pollution. A plethora of kitchen utensils, encompassing coated non-stick pans, plastic cutting boards, and disposable utensils, are known to release substantial quantities of MPs particles in everyday use, which can then be ingested alongside food. This paper conducts a thorough examination of contemporary research addressing the release of MPs from kitchen utensils during usage and focuses on the health risks associated with MPs ingestion, as well as the myriad factors influencing the release of MPs in kitchen utensils. Leveraging the insights derived from this analysis, this paper proposes a series of strategic recommendations and measures targeted at mitigating the production of MPs in kitchen settings. These initiatives are designed not solely to diminish the release of MPs but also to enhance public awareness regarding this pressing environmental concern. By adopting more informed practices in kitchens, we can significantly contribute to the reduction of the environmental burden of MPs pollution, thus safeguarding both human health and the ecological system.

Microplastics: Omnipresent and an ongoing challenge for medical science

Micro- and nanoplastics are omnipresent not only in the environment, but have also been detected in human body fluids and tissue. The subsequent commentary provides a perspective about potential risks for human health as well as resulting challenges for medical science.

Polystyrene nanoplastics exposure triggers spermatogenic cell senescence via the Sirt1/ROS axis

Polystyrene nanoplastics (PS-NPs) have been reported to accumulate in the testes and constitute a new threat to reproductive health. However, the exact effects of PS-NPs exposure on testicular cells and the underlying mechanisms remain largely unknown. The C57BL/6 male mice were orally administered with PS-NPs (80 nm) at different dosages (0, 10, and 40 mg/kg/day) for 60 days, and GC-1 cells were treated with PS-NPs in this study. Enlarged seminiferous tubule lumens and a loose and vacuolated layer of spermatogenic cells were observed in PS-NPs-exposed mice. Spermatogenic cells which may be one of the target cells for this reproductive damage, were decreased in the mice from PS-NPs group. PS-NPs caused spermatogenic cells to undergo senescence, manifested as elevated SA-β-galactosidase activity and activated senescence-related signaling p53-p21/Rb-p16 pathways, and induced cell cycle arrest. Mechanistically, Gene Ontology (GO) enrichment suggested the key role of reactive oxygen species (ROS) in PS-NPs-induced spermatogenic cell senescence, and this result was confirmed by measuring ROS levels. Moreover, ROS inhibition partially attenuated the senescence phenotype of spermatogenic cells and DNA damage. Using the male health atlas (MHA) database, Sirt1 was filtrated as the critical molecule in the regulation of testicular senescence. PS-NPs induced overexpression of the main ROS generator Nox2, downregulated Sirt1, increased p53 and acetylated p53 in vivo and in vitro, whereas these disturbances were partially restored by pterostilbene. In addition, pterostilbene intervention significantly alleviated the PS-NPs-induced spermatogenic cell senescence and attenuated ROS burst. Collectively, our study reveals that PS-NPs exposure can trigger spermatogenic cell senescence mediated by p53-p21/Rb-p16 signaling by regulating the Sirt1/ROS axis. Importantly, pterostilbene intervention may be a promising strategy to alleviate this damage.

Potential health risks of microplastic fibres release from disposable surgical masks: Impact of repeated wearing and handling

Disposable surgical masks undeniably provide important personal protection in daily life, but the potential health risks by the release of microplastic fibres from masks should command greater attention. In this study, we conducted a microplastic fibre release simulation experiment by carrying masks in a pocket and reusing them, to reveal the number and morphological changes of microfibres released. Fourier transform infrared spectrometry, scanning electron microscopy, and optical microscopy were employed to analyse the physical and chemical characteristics of the mask fibres. The results indicated that the reuse of disposable masks led to a significant release of microplastic fibres, potentially leading to their migration into the respiratory system. Furthermore, the release of microplastic fibres increased with prolonged external friction, particularly when masks were stored in pockets. The large-scale release of microplastic fibres due to mask reuse raises concerns about potential health risks to the human respiratory system. The reuse of disposable masks should be also strictly avoided in daily life in the future. Furthermore, the current study also established a robust foundation for future research endeavours on health risks associated with microplastic fibres entering the respiratory system through improper mask usage.

Reactive oxygen species-scavenging nanomaterials for the prevention and treatment of age-related diseases

With increasing proportion of the elderly in the population, age-related diseases (ARD) lead to a considerable healthcare burden to society. Prevention and treatment of ARD can decrease the negative impact of aging and the burden of disease. The aging rate is closely associated with the production of high levels of reactive oxygen species (ROS). ROS-mediated oxidative stress in aging triggers aging-related changes through lipid peroxidation, protein oxidation, and DNA oxidation. Antioxidants can control autoxidation by scavenging free radicals or inhibiting their formation, thereby reducing oxidative stress. Benefiting from significant advances in nanotechnology, a large number of nanomaterials with ROS-scavenging capabilities have been developed. ROS-scavenging nanomaterials can be divided into two categories: nanomaterials as carriers for delivering ROS-scavenging drugs, and nanomaterials themselves with ROS-scavenging activity. This study summarizes the current advances in ROS-scavenging nanomaterials for prevention and treatment of ARD, highlights the potential mechanisms of the nanomaterials used and discusses the challenges and prospects for their applications.

Differences in toxicity induced by the various polymer types of nanoplastics on HepG2 cells

The problem of microplastics (MPs) contamination in food has gradually come to the fore. MPs can be transmitted through the food chain and accumulate within various organisms, ultimately posing a threat to human health. The concentration of nanoplastics (NPs) exposed to humans may be higher than that of MPs. For the first time, we studied the differences in toxicity, and potential toxic effects of different polymer types of NPs, namely, polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polystyrene (PS) on HepG2 cells. In this study, PET-NPs, PVC-NPs, and PS-NPs, which had similar particle size, surface charge, and shape, were prepared using nanoprecipitation and emulsion polymerization. The results of the CCK-8 assay showed that the PET-NPs and PVC-NPs induced a decrease in cell viability in a concentration-dependent manner, and their lowest concentrations causing significant cytotoxicity were 100 and 150 μg/mL, respectively. Moreover, the major cytotoxic effects of PET-NPs and PVC-NPs at high concentrations may be to induce an increase in intracellular ROS, which in turn induces cellular damage and other toxic effects. Notably, our study suggested that PET-NPs and PVC-NPs may induce apoptosis in HepG2 cells through the mitochondrial apoptotic pathway. However, no relevant cytotoxicity, oxidative damage, and apoptotic toxic effects were detected in HepG2 cells with exposure to PS-NPs. Furthermore, the analysis of transcriptomics data suggested that PET-NPs and PVC-NPs could significantly inhibit the expression of DNA repair-related genes in the p53 signaling pathway. Compared to PS-NPs, the expression levels of lipid metabolism-related genes were down-regulated to a greater extent by PET-NPs and PVC-NPs. In conclusion, PET-NPs and PVC-NPs were able to induce higher cytotoxic effects than PS-NPs, in which the density and chemical structure of NPs of different polymer types may be the key factors causing the differences in toxicity.

Unraveling the micro- and nanoplastic predicament: A human-centric insight

Micro- and nanoplastics are vast anthropogenic pollutants in our direct surroundings with a robust environmental stability and a potential for a long-lasting and increasing global circulation. This has raised concerns among the public and policy makers for human health upon exposure to these particles. The micro- and nanoplastic burden on humans is currently under debate, along with criticism on the experimental approaches used in hazard assessment. The present review presents an overview of the human-relevant aspects associated with the current micro-and nanoplastic burden. We focus on environmental circulation and the estimation of exposure quantities to humans, along with a state-of-the-art overview of particle accumulation in over 15 human organs and other specimen. Additionally, data regarding particle characteristics used in toxicity testing was extracted from 91 studies and discussed considering their environmental and human relevance.

Molecular mechanisms of nano-sized polystyrene plastics induced cytotoxicity and immunotoxicity in Eisenia fetida

Nanoplastics (NPs) are currently everywhere and environmental pollution by NPs is a pressing global problem. Nevertheless, until now, few studies have concentrated on the mechanisms and pathways of cytotoxic effects and immune dysfunction of NPs on soil organisms employing a multidimensional strategy. Hence, earthworm immune cells and immunity protein lysozyme (LZM) were selected as specific receptors to uncover the underlying mechanisms of cytotoxicity, genotoxicity, and immunotoxicity resulting from exposure to polystyrene nanoplastics (PS-NPs), and the binding mechanisms of PS-NPs-LZM interaction. Results on cells indicated that when earthworm immune cells were exposed to high-dose PS-NPs, it caused a notable rise in the release of reactive oxygen species (ROS), resulting in oxidative stress. PS-NPs exposure significantly decreased the cell viability of earthworm immune cells, inducing cytotoxicity through ROS-mediated oxidative stress pathway, and oxidative injury effects, including reduced antioxidant defenses, lipid peroxidation, DNA damage, and protein oxidation. Moreover, PS-NPs stress inhibited the intracellular LZM activity in immune cells, resulting in impaired immune function and immunotoxicity by activating the oxidative stress pathway mediated by ROS. The results from molecular studies revealed that PS-NPs binding destroyed the LZM structure and conformation, including secondary structure changes, protein skeleton unfolding/loosening, fluorescence sensitization, microenvironment changes, and particle size changes. Molecular docking suggested that PS-NPs combined with active center of LZM easier and inhibited the protein function more, and formed a hydrophobic interaction with TRP 62, a crucial amino acid residue closely associated with the function and conformation of LZM. This is also responsible for LZM conformational changes and functional inhibition /inactivation. These results of this research offer a fresh outlook on evaluating the detriment of NPs to the immune function of soil organisms using cellular and molecular strategies.

Maternal exposure to polystyrene nanoplastics causes defective retinal development and function in progeny mice by disturbing metabolic profiles

Microplastics (MPs) and nanoplastics (NPs) are widely spreading in our living environment, accumulating in the human body and potentially threating human health. The retina, which is a terminally differentiated extension of the central nervous system, is essential for the visual system. However, the effects and molecular mechanisms of MPs/NPs on retina development and function are still unclear. Here, we investigated the effects and modes of action of polystyrene NPs (PS-NPs) on the retina using mice as a mammalian model species. Maternal PS-NP exposure (100 nm) at an environmentally realistic concentration of 10 mg L-1 (or 2.07 *1010 particles mL-1) via drinking water from the first day of pregnancy till the end of lactation (21 days after birth) caused defective neural retinal development in the neonatal mice, by depositing in the retinal tissue and reducing the number of retinal ganglion cells and bipolar cells. Exposure to PS-NPs retarded retinal vascular development, while abnormal electroretinogram (ERG) responses and an increased level of oxidative stress were also observed in the retina of the progeny mice after maternal PS-NP exposure. Metabolomics showed significant dysregulation of amino acids that are pivotal to neuron retinal function, such as glutamate, aspartate, alanine, glycine, serine, threonine, taurine, and serotonin. Transcriptomics identified significantly dysregulated genes, which were enriched in processes of angiogenesis, visual system development and lens development. Regulatory analysis showed that Fos gene mediated pathways could be a potential key target for PS-NP exposure in retinal development and function. Our study revealed that maternal exposure to PS-NPs generated detrimental effects on retinal development and function in progeny mice, offering new insights into the visual toxicity of PS-NPs.

Molecular mechanism for combined toxicity of micro(nano)plastics and carbon nanofibers to freshwater microalgae Chlorella pyrenoidosa

The understanding of the environmental consequences resulting from the presence of micro(nano)plastics and carbon nanofibers (CNFs) in aquatic ecosystems is currently limited. This research endeavor sought to investigate the underlying molecular mechanisms by which engineered polystyrene-based microplastics (MPs)/nanoplastics (NPs) and CNFs, both individually and in combination, elicit toxic effects on an algal species Chlorella pyrenoidosa. The findings revealed that the combined toxicity of MPs/NPs and CNFs depended on the concentration of the mixture. As the concentration increased, the combined toxicity of MPs/NPs and CNFs was significantly greater than the toxicity of each component on its own. Furthermore, the combined toxicity of NPs and CNFs was higher than that of MPs and CNFs. The study integrated data on cell membrane integrity, oxidative stress, and antioxidant modulation to create an Integrated Biomarker Response index, which demonstrated that the co-exposure of algae to NPs and CNFs resulted in more severe cellular stress compared to exposure to NPs alone. Similarly, the combination of NPs and CNFs caused greater cellular stress than the combination of MPs and CNFs. Additionally, significant changes in the expression of stress-related genes caused by MPs/NPs alone and in combination with CNFs indicated that oxidative stress response, glucose metabolism, and energy metabolism played critical roles in particle-induced toxicity. Overall, this study provides the first insight into the toxicological mechanism of MPs/NPs and CNFs mixtures at the molecular level in freshwater microalgae.

Polystyrene micro- and nanoplastics induce gastric toxicity through ROS mediated oxidative stress and P62/Keap1/Nrf2 pathway

Microplastics (MPs) exist widely in the environment and can enter the human body indirectly through the food chain or directly through inhalation or ingestion. The primary organ that MPs contaminated food or water enters the human body through the digestive tract is the stomach. However, at present, the effects of MPs on the stomach and the related mechanism remain unclear. In this study, our results indicated that 50 nm and 250 nm polystyrene MPs (PS-MPs) at environmental related dose significantly decreased stomach organ coefficient, inhibited gastric juice secretion and mucus secretion, disrupted gastric barrier function and suppressed antioxidant ability in mice. In vitro experiments showed that PS-MPs inhibited cell viability, increased ROS generation, and induced apoptosis through mitochondria-dependent pathway. Simultaneously, PS-MPs also decreased mitochondrial membrane potential, ATP level, disrupted mitochondrial kinetic homeostasis, and activated P62 / Nrf2 / Keap1 pathway. Furthermore, blocking ROS (NAC) partially alleviated ROS and apoptosis caused by PS-MPs. Based on above findings, the potential adverse outcome pathway (AOP) of PS-MPs-caused gastric toxicity was proposed which provides a new insight into the risk assessment of MP related gastric damage. Our study unveils the gastric injury induced by PS MPs is dependent on ROS - mediated P62 / Nrf2 / Keap1 signaling pathway, and provides scientific basis for further exploration the mechanism of gastric toxicity of PS MPs.

Understanding the mechanistic roles of microplastics combined with heavy metals in regulating ferroptosis: Adding new paradigms regarding the links with diseases

As a new type of pollutant, microplastics (MPs) commonly exist in today's ecosystems, causing damage to the ecological environment and the health of biological organisms, including human beings. MPs can function as carriers of heavy metals (HMs) to aggravate the enrichment of HMs in important organs of organisms, posing a great threat to health. Ferroptosis, a novel process for the regulation of nonapoptotic cell death, has been shown to be closely related to the occurrence and processes of MPs and HMs in diseases. In recent years, some HMs, such as cadmium (Cd), iron (Fe), arsenic (As) and copper (Cu), have been proven to induce ferroptosis. MPs can function as carriers of HMs to aggravate damage to the body. This damage involves oxidative stress, mitochondrial dysfunction, lipid peroxidation (LPO), inflammation, endoplasmic reticulum stress (ERS) and so on. Therefore, ferroptosis has great potential as a therapeutic target for diseases induced by MPs combined with HMs. This paper systematically reviews the potential effects and regulatory mechanisms of MPs and HMs in the process of ferroptosis, focusing on the mitochondrial damage, Fe accumulation, LPO, ERS and inflammation caused by MPs and HMs that affect the regulatory mechanism of ferroptosis, providing new insights for research on regulating drugs and for the development of ferroptosis-targeting therapy for Alzheimer's disease, Parkinson's disease, cancer and cardiovascular disease.

Probiotic Lactobacillus rhamnosus alleviates the neurotoxicity of microcystin-LR in zebrafish (Danio rerio) through the gut-brain axis

Microcystin-LR (MCLR) is one of the most toxic cyanobacterial toxins and is harmful to the central nervous system of fish. Probiotic additives can improve neuroendocrine function in fish. Although both MCLR and probiotics aim at the nervous system, whether they interact with each other and the mechanisms remain unexplored. In the present study, 4-month-old zebrafish were exposed to 0, 2.2, and 22 μg/L of MCLR for 28 days with or without the probiotic L. rhamnosus. We found that MCLR exposure could inhibit the swimming speed of zebrafish, while the presence of L. rhamnosus mitigated this abnormality. To elucidate the mechanism of how L. rhamnosus alleviates MCLR-induced neurotoxicity, we examined the bioaccumulation of MCLR, changes in neurotransmitters, immune biochemical indicators, and hormone content of the hypothalamic-pituitary-interrenal (HPI) axis in zebrafish along the gut-brain axis. Our results showed L. rhamnosus could reverse the abnormal swimming behavior and eventually alleviate neurotoxicity in zebrafish by modulating intestinal and brain neural signaling, neuroinflammation, and HPI axis responses. This study provides implications for the application of probiotics in the aquaculture industry.

The combined effects of phenanthrene and micro-/nanoplastics mixtures on the cellular stress responses of the thick-shell mussel Mytilus coruscus

Pollution with complex mixtures of contaminants including micro- and nano-plastics (MNPs) and organic pollutants like polycyclic aromatic hydrocarbons (PAH) poses a major threat to coastal marine ecosystems. Toxic mechanisms of contaminant mixtures are not well understood in marine organisms. We studied the effects of single and combined exposures to polycyclic aromatic hydrocarbon phenanthrene (Phe) and MNPs mixture with sizes of 70 nm, 5 μm and 100 μm on the immune health and oxidative stress parameters in the thick-shell mussel Mytilus coruscus. Immune cells (hemocytes) were more sensitive to the pollutant-induced oxidative stress than the gills. In hemocytes of co-exposed mussels, elevated mortality, lower lysosomal content, high production of reactive oxygen species (ROS) and decrease mitochondrial were found. Disparate responses of antioxidant enzymes in the hemolymph (e.g. increased superoxide dismutase (SOD) activity without a corresponding increase in catalase (CAT) in Phe exposures and an increase in CAT without a change in SOD in MNPs exposures) suggests misbalance of the antioxidant defense in the pollutant-exposed mussels. Gill lacked pronounced oxidative stress response showing a decline in ROS and antioxidant levels. Tissue-specific single and combined effects of Phe and MNPs suggest variation in bioavailability and/or different sensitivity to these pollutants in the studied tissues. Notably, the combined effects of MNPs and Phe were additive or antagonistic, showing that MNPs do not enhance and occasionally mitigate the toxic effects of Phe on the hemocytes and the gills of the mussels. Overall, our study sheds light on the impact of long-term exposure to MNPs and Phe mixtures on mussels, showing high sensitivity of the immune system and modulation of the Phe toxicity by MNPs co-exposure. These findings that may have implications for understanding the impacts of combined PAH and MNPs pollution on the health of mussel populations from polluted coastal habitats.

Identification and analysis of microplastics in human lower limb joints

Microplastics (MPs) have been detected in various human tissues, including the liver, placenta, and blood. However, studies about MPs in the human locomotor system are limited. This study evaluated the presence of MPs in the synovium of 45 patients undergoing hip or knee arthroplasty using micro-Fourier transform infrared spectroscopy, scanning electron microscopy, and Raman microscopy and investigated their association with clinical indicators and local cellular responses. A total of 343 MPs of nine common types were identified, with a mean abundance of 5.24 ± 2.07 particles/g and ranging from 1.16 to 10.77 particles/g. Although there was no clear correlation between MP abundance and demographics, MP abundance was higher in hip samples than in knee samples. In addition, a potential association was observed between MP abundance and specific clinical diagnoses. Transcriptomic analysis revealed that a three-fold increase in MP abundance corresponded to enhanced local cellular stress responses, particularly heat shock protein reactions. Our findings demonstrate the presence of MPs in human joints and suggest that further studies are needed to explore the intricate associations between MPs and anatomical location, clinical diagnosis, and local cellular responses.

A case study on microplastics pollution characteristics in fouling organisms in typical aquaculture bay, China

Microplastics (MPs) and fouling organisms are prevalent in oceans worldwide. The study aims to investigate the pollution characteristics of MPs in fouling organisms. The study found significant inter-specific differences in the MPs abundance, while the length of MPs is consistent. The average number of MPs in N. exigua is 0.00 ± 0.00. There is a correlation between MPs abundance and weight in sessile group, while gastropods don't. Direct observation has demonstrated that the radulae of N. radula can envelop MPs. Fiber and blue are the predominant forms and colors of MPs found in fouling organisms. It is noteworthy that all film and fragment MPs observed were of a blue hue and had a size limitation of 500 μm. The characteristics of MPs between sessile organisms are more similar than those between gastropods. This study has improved our understanding of the pollution characteristics of MPs in fouling organisms, specifically gastropods.

Detection and quantification of various microplastics in human endometrium based on laser direct infrared spectroscopy

The pollution of microplastics (MPs) has received widespread attention with the increasing usage of plastics in recent years. MPs could enter the human body and exist in the circulatory system. Endometrium, with rich blood vessels, acts as an essential role in human health and female fertility. However, there is no study reporting the MPs exposure in human endometrium. We collected the endometrium samples to detect the presence of MPs qualitatively and quantitatively via laser direct infrared. We found that there was a total of 13 types of MPs existing in the collected samples, among which 6 special types of MPs were with both high abundance and high detection rate. The abundance of these MPs ranged from 0 to 117 particles/100 mg, with a median abundance of 21 particles/100 mg. Most detected MPs, accounting for 88.35 %, were in small size (20-100 μm). Among small-size MPs, ethylene-acrylic acid copolymer ranked first while polyethylene accounted for the largest proportion among large-size MPs (100-500 μm). Correlation analysis indicated there was no significant relationship between age and MP abundance or BMI and MP abundance. We also designed a questionnaire to investigate lifestyle and daily habits, aiming at revealing the potential relationship between MP exposure and living habits. We discovered that some drinking habits and chewing gum were significantly correlated with a higher level of MP exposure. For the first time, we identified the presence of MPs in human endometrium and clarified the potential connections between MP exposure and lifestyle. Further studies are still necessary to explore more underlying information.