Platform to study intracellular polystyrene nanoplastic pollution and clinical outcomes

Effects of microplastics on the immune system: How much should we worry?

Plastics are everywhere. It is widely recognized that they represent a global problem, the extent of which is yet to be defined. Humans are broadly exposed to plastics, whose effects and consequences are poorly characterized so far. The main route of exposure is via alimentary and respiratory intake. Plastics pollutions may come from both: water and food contamination itself, and their packaging. The smaller sizes (i.e. microplastics <150µm - MPs) are considered to be the most pervasive of living organisms and, therefore, potentially the most harmful. As humans occupy one of the apex positions of the food chain, we are exposed to bioaccumulation and biomagnification effects of MPs. In fact, MPs are commonly found in human stools and blood. However, there are no data available yet on their ability to accumulate and to produce detrimental consequences on biological systems. Even though the effects of plastics pollution are poorly studied in mammals, including humans, they appear to have inflammatory effects, which is rather concerning as many etiologies of disease are based on a pro-inflammatory status.

NO-mediated DNA damage induced by polystyrene nanoparticles triggers program cell death in mesenchymal stem cells

Daily contact with considerable amounts of polystyrene nanoparticles (PSNPs) may cause harmful effects on the living organisms, through mechanisms that are not fully understood. The study aimed to evaluate the cytotoxic and genotoxic effects of PSNPs (size 200 nm and 40 nm) in mesenchymal stem cells (MSCs). In order to estimate cellular uptake and retention of nanoplastics, PSNP-treated cells have been analyzed by transmission electron microscopy. For assessing morphology and viability of MSCs after PSNP treatment at two environmentally relevant doses (0.47 and 4.7 μl/ml) for 24 hours, HE and Giemsa staining were performed. Annexin V‑FITC/PI assay was used to quantify PSNPs-mediated cell death. Genotoxicity of PSNPs was evaluated by Comet test. The capacity of PSNPs to trigger the production of free radicals in MSCs was also evaluated. TEM confirmed endocytosis of PSNPs. Decreased cell volume, nuclear hyperchromatism, edge aggregation, and formation of densely stained apoptotic bodies, indicated that PSNP-treated MSCs undergo apoptosis. The presented data showed that both concentration of PS particles significantly increased early apoptotic cell death in comparison to untreated cells. Moreover, both doses of PSNPs significantly increased the genetic damage index in MSCs in dose-dependent manner. In conclusion, PSNPs penetrate, accumulate and induce cytotoxic and genotoxic damage in MSCs.

Nano-scale dangers: Unravelling the impact of nanoplastics on human trophoblast invasion

Utilizing HTR-8/SVneo cells for in vitro modeling of human trophoblast invasion, we examined how different concentrations of 40 nm and 200 nm carboxylated polystyrene particles affect early-pregnancy trophoblast phenotype and function. We focused on migration and invasion, as critical processes in placental development. Our findings revealed disruptions in extravillous trophoblast mesenchymal phenotype and invasive behavior, following acute exposure to a higher concentration of the smaller sized particles. Specifically, differential uptake of the particles by trophoblast cells was observed, as well as cytotoxicity and concentration-dependent DNA damage after 72 h of exposure. In addition, a 24 h exposure to 100 μg/ml of 40 nm particles correlated with downregulated protein expression of α5 and α1 integrin subunits, N-cadherin, matrix metalloproteinase-2 and macrophage migration inhibitory factor, alongside upregulated protein expression of the epithelial marker E-cadherin. These changes likely contributed to the diminished migration of HTR-8/SVneo cells and the invasive potential of HTR-8/SVneo spheroids. Understanding these interactions is paramount for assessing the broader implications of nanoplastics on reproductive outcomes and maternal-fetal well-being and informing public health measures.

Impact of micro-nano plastics in daily life on human health: toxicological evaluation from the perspective of normal tissue cells and organoids

Plastics are the most frequently used materials in people's daily life, and the primary and secondary microplastics generated from them may harm the health of adults. This paper focuses on the summary of the existence of microplastics in many objects most closely related to people in daily life, the toxicological influences it causes in cultured human normal cells and organoids, and the prospects for future research directions. Micro- and nano-plastics (MNPs) are found in almost all of our everyday products, such as food, drink, and daily necessities, etc. It can enter the digestive tract, respiratory system, and body fluids of the human body, and at lower or equal environment concentrations exhibits obvious cytotoxicity and genotoxicity toward cells and organoids, probably becoming a kind of toxin affecting human health. In addition, due to MNPs can be transferred from the placenta to the embryo, long-term growth-tracking studies of newborns should be done vitally. Besides, due to their wide usability in daily products and the ability to penetrate cytomembranes, the toxicological effects of polyethylene and polypropylene nanoplastic particles equal to or lower than environmental (normal exposure to human body) concentrations are recommended to be studied on human health in the future. Finally, for those individuals who carry MNPs, long-term health evaluation must be performed.

Unveiling the impacts of microplastic pollution on soil health: A comprehensive review

Soil contamination by microplastics (MPs) has emerged as a significant global concern. Although traditionally associated with crop production, contemporary understanding of soil health has expanded to include a broader range of factors, including animal safety, microbial diversity, ecological functions, and human health protection. This paradigm shifts underscores the imperative need for a comprehensive assessment of the effects of MPs on soil health. Through an investigation of various soil health indicators, this review endeavors to fill existing knowledge gaps, drawing insights from recent studies conducted between 2021 and 2024, to elucidate how MPs may disrupt soil ecosystems and compromise their crucial functions. This review provides a thorough analysis of the processes leading to MP contamination in soil environments and highlights film residues as major contributors to agricultural soils. MPs entering the soil detrimentally affect crop productivity by hindering growth and other physiological processes. Moreover, MPs hinder the survival, growth, and reproductive rates of the soil fauna, posing potential health risks. Additionally, a systematic evaluation of the impact of MPs on soil microbes and nutrient cycling highlights the diverse repercussions of MP contamination. Moreover, within soil-plant systems, MPs interact with other pollutants, resulting in combined pollution. For example, MPs contain oxygen-containing functional groups on their surfaces that form high-affinity hydrogen bonds with other pollutants, leading to prolonged persistence in the soil environment thereby increasing the risk to soil health. In conclusion, we succinctly summarize the current research challenges related to the mediating effects of MPs on soil health and suggest promising directions for future studies. Addressing these challenges and adopting interdisciplinary approaches will advance our understanding of the intricate interplay between MPs and soil ecosystems, thereby providing evidence-based strategies for mitigating their adverse effects.

The Construction of Stem Cell-Induced Hepatocyte Model and Its Application in Evaluation of Developmental Hepatotoxicity of Environmental Pollutants

Stem cells, with their ability to self-renew and differentiate into various cell types, are a unique and valuable resource for medical research and toxicological studies. The liver is the most crucial metabolic organ in the human body and serves as the primary site for the accumulation of environmental pollutants. Enrichment with environmental pollutants can disrupt the early developmental processes of the liver and have a significant impact on liver function. The liver comprises a complex array of cell types, and different environmental pollutants have varying effects on these cells. Currently, there is a lack of well-established research models that can effectively demonstrate the mechanisms by which environmental pollutants affect human liver development. The emergence of liver cells and organoids derived from stem cells offers a promising tool for investigating the impact of environmental pollutants on human health. Therefore, this study systematically reviewed the developmental processes of different types of liver cells and provided an overview of studies on the developmental toxicity of various environmental pollutants using stem cell models.

Maternal exposure to polystyrene nanoplastics induces sex-specific cardiotoxicity in offspring mice

Globally, plastic pollution threatens human health, particularly affecting the hearts of offspring exposed to maternal environmental factors early in development. Few studies have specifically addressed sex-specific cardiac injury in offspring resulting from maternal exposure to polystyrene nanoplastics (PS-NPs). This study investigates the potential cardiac injury in offspring following maternal exposure to 1 mg/L PS-NPs. Pregnant C57BL/6J mice were exposed to PS-NPs until 3 weeks postpartum to establish a maternal exposure model. Heart tissues were collected and weighed, and the transcriptomes of the offspring hearts were sequenced and analyzed using high-throughput RNA sequencing. Immunohistochemical staining was performed to assess the effects of PS-NPs on cardiac immune infiltration, fibrosis, and apoptosis in the offspring. PS-NPs caused a significant reduction in heart and body weight in female offspring compared to males. Additionally, PS-NPs induced sex-specific transcriptional reprogramming and metabolic disruptions in the offspring. PS-NPs also induced significant fibrosis, apoptosis, and increased CD68+ macrophage infiltration in offspring hearts. Notably, PS-NPs induced distinct cardiovascular diseases in the offspring. Fluid shear stress and atherosclerosis were significantly enriched in PS-NP-treated male offspring, while viral myocarditis was predominantly enriched in PS-NP-treated females. Our findings suggest that PS-NPs induce cardiotoxicity in offspring by disrupting metabolism, impairing immunity, and triggering fibrosis and apoptosis, with sex-specific differences. This study provides novel insights and a foundation for understanding sex-specific pharmacological differences and interventions in PS-NP-induced cardiovascular disease in offspring.

Microplastics and nanoplastics in cardiovascular disease-a narrative review with worrying links

With the widespread use of plastic products and the increase in waste, microplastics and nanoplastics (MNPs) have become an important issue in global environmental pollution. In recent years, an increasing number of studies have shown that MNPs may have negative impacts on human health. This review aimed to explore the association between MNPs and cardiovascular disease and provide an outlook for future research. Research has shown that there may be a link between MNPs exposure and cardiovascular disease. Laboratory studies have shown that animals exposed to MNPs often exhibit abnormalities in the cardiovascular system, such as increased blood pressure, vascular inflammation, and myocardial damage. Epidemiological surveys have also revealed that people exposed to MNPs are more likely to suffer from cardiovascular diseases, such as hypertension and myocardial infarction. Although the specific impact mechanism is not fully understood, there are several possible pathways of action, including the effects of toxic substances on MNPs and interference with the endocrine system. In summary, MNPs exposure may have a negative impact on cardiovascular health, but further research is needed to confirm its specific mechanism and extent of impact to guide relevant public health and environmental policies.

Interaction of Micro- and Nanoplastics with Enzymes: The Case of Carbonic Anhydrase

Microplastics (MPs) and nanoplastics (NPs) have emerged as significant environmental pollutants with potential detrimental effects on ecosystems and human health. Several studies indicate their interaction with enzymes; this topic represents a multifaceted research field encompassing several areas of interest from the toxicological and ecotoxicological impact of MPs and NPs on humans and wildlife to the biodegradation of plastics by microbial enzymes. This review aims to provide a critical analysis of the state-of-the-art knowledge of the interaction of MPs and NPs on the enzyme carbonic anhydrase (CA), providing recent insights, analyzing the knowledge gaps in the field, and drawing future perspectives of the research and its application. CA is a widespread and crucial enzyme in various organisms; it is critical for various physiological processes in animals, plants, and bacteria. It catalyzes the reversible hydration of CO2, which is essential for respiration, acid-base balance, pH homeostasis, ion transport, calcification, and photosynthesis. Studies demonstrate that MPs and NPs can inhibit CA activity with mechanisms including adsorption to the enzyme surface and subsequent conformational changes. In vitro and in silico studies highlight the role of electrostatic and hydrophobic interactions in these processes. In vivo studies present mixed results, which are influenced by factors like particle type, size, concentration, and organism type. Moreover, the potentiality of the esterase activity of CA for plastic degradation is discussed. The complexity of the interaction between CA and MPs/NPs underscores the need for further research to fully understand the ecological and health impacts of MPs and NPs on CA activity and expression and glimpses of the potentiality and perspectives in this field.

The possible impacts of nano and microplastics on human health: lessons from experimental models across multiple organs

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

Embryonic exposure of polystyrene nanoplastics affects cardiac development

Micro- and nanoplastics have recently been detected in human blood and placentas, indicating inevitable embryonic exposure to these particles. However, their influence on human embryogenesis and the underlying mechanisms are still unknown. In this study, the effects of polystyrene nanoplastics (PS-NPs) exposure on cardiac differentiation of human embryonic stem cells (hESCs) were evaluated. Uptake of PS-NPs not only caused cellular injury, but also regulated cardiac-related pathways as revealed by RNA-sequencing. Consequently, the efficiency of cardiomyocyte differentiation from hESCs was compromised, leading to immature of cardiomyocytes and smaller cardiac organoids with impaired contractility. Mechanistically, PS-NPs promoted mitochondrial oxidative stress, activated P38/Erk MAPK signaling pathway, blocked autophagy flux, and eventually reduced the pluripotency of hESCs. Consistently, in vivo exposure of PS-NPs from cleavage to gastrula period of zebrafish embryo led to reduced cardiac contraction and blood flow. Collectively, this study suggests that PS-NPs is a risk factor for fetal health, especially for heart development.

The potential impacts of micro-and-nano plastics on various organ systems in humans

Humans are exposed to micro-and-nano plastics (MNPs) through various routes, but the adverse health effects of MNPs on different organ systems are not yet fully understood. This review aims to provide an overview of the potential impacts of MNPs on various organ systems and identify knowledge gaps in current research. The summarized results suggest that exposure to MNPs can lead to health effects through oxidative stress, inflammation, immune dysfunction, altered biochemical and energy metabolism, impaired cell proliferation, disrupted microbial metabolic pathways, abnormal organ development, and carcinogenicity. There is limited human data on the health effects of MNPs, despite evidence from animal and cellular studies. Most of the published research has focused on specific types of MNPs to assess their toxicity, while other types of plastic particles commonly found in the environment remain unstudied. Future studies should investigate MNPs exposure by considering realistic concentrations, dose-dependent effects, individual susceptibility, and confounding factors.

Low-dose of polystyrene microplastics induce cardiotoxicity in mice and human-originated cardiac organoids

Microplastic particles (MP) are prevalent in both industrial production and the natural environment, posing a significant concern for human health. Daily diet, air inhalation, and skin contact are major routines of MP intake in human. The main injury target systems of MPs include the digestive system, respiratory system, and cardiovascular system. However, the study on MPs' adverse effects on the heart is less than other target organs. Previous in vivo studies have demonstrated that MPs can induce heart injuries, including abnormal heart rate, apoptosis of cardiomyocytes, mitochondrial membrane potential change, and fibrin overexpression. To address animal welfare concerns and overcome inter-species variations, this study employed a human pluripotent stem cell-derived in vitro three-dimensional cardiac organoid (CO) model to investigate the adverse effects of MPs on the human heart. The distinct cavities of COs allowed for the observation of MPs' aggregation and spatial distribution following polystyrene-MP (PS) exposure in a dynamic exposure system. After exposure to various concentrations of PS (0.025, 0.25 and 2.5 µg/mL, with the lowest concentration equivalent to human internal exposure levels), the COs exhibited increased oxidative stress, inflammatory response, apoptosis, and collagen accumulation. These findings were consistent with in vivo observations, in terms of increases in the interventricular septal thickness. The expression of hypertrophic-related genes of COs (MYH7B/ANP/BNP/COL1A1) changed noticeably and the cardiac-specific markers MYL2/MYL4/CX43 were also markedly elevated. Our findings revealed the PS could induced cardiac hypertrophy in vivo and in vitro, indicating that MP may be an under-recognized risk factor for cardiovascular system.

Toxicity of microplastics and nanoplastics: invisible killers of female fertility and offspring health

Microplastics (MPs) and nanoplastics (NPs) are emergent pollutants, which have sparked widespread concern. They can infiltrate the body via ingestion, inhalation, and cutaneous contact. As such, there is a general worry that MPs/NPs may have an impact on human health in addition to the environmental issues they engender. The threat of MPs/NPs to the liver, gastrointestinal system, and inflammatory levels have been thoroughly documented in the previous research. With the detection of MPs/NPs in fetal compartment and the prevalence of infertility, an increasing number of studies have put an emphasis on their reproductive toxicity in female. Moreover, MPs/NPs have the potential to interact with other contaminants, thus enhancing or diminishing the combined toxicity. This review summarizes the deleterious effects of MPs/NPs and co-exposure with other pollutants on female throughout the reproduction period of various species, spanning from reproductive failure to cross-generational developmental disorders in progenies. Although these impacts may not be directly extrapolated to humans, they do provide a framework for evaluating the potential mechanisms underlying the reproductive toxicity of MPs/NPs.

High-Content Screening Discovers Microplastics Released by Contact Lenses under Sunlight

The widespread use of plastic products leads to the ubiquity of microplastics in daily life, while the release of microplastics from long-used contact lenses has not been reported due to the limitations of conventional detection methods. Here, we established a new and rapid method to capture and count microplastics by using a high-content screening system. This method can simultaneously measure the diameter, area, and shape of each plastic particle, and the reliability and applicability of this method were verified with commercial microplastics. It is estimated that 90,698 particles of microplastics could be released from a pair of contact lenses during a year of wearing. The microplastics in the leachates were confirmed to be released from the contact lenses by scanning electron microscopy and Fourier transform infrared spectroscopy fingerprint analysis. Our study reveals an undiscovered pathway of microplastic direct exposure to humans, highlighting the urgent need to assess the potential health risks caused by eye exposure to microplastics.

Research advances of microplastics and potential health risks of microplastics on terrestrial higher mammals: a bibliometric analysis and literature review

Microplastics (MPs) have become increasingly serious global problems due to their wide distribution and complicated impacts on living organisms. To obtain a comprehensive overview of the latest research progress on MPs, we conducted a bibliometric analysis combined with a literature review. The results showed that the number of studies on MPs has grown exponentially since 2010. Recently, the hotspot on MPs has shifted to terrestrial ecosystems and biological health risks, including human health risks. In addition, the toxic effects, identification and quantification of MPs are relatively new research hotspots. We subsequently provide a review of MPs studies related to health risks to terrestrial higher mammals and, in particular, to humans, including detection methods and potential toxicities based on current studies. Currently, MPs have been found existing in human feces, blood, colon, placenta and lung, but it is still unclear whether this is associated with related systemic diseases. In vivo and in vitro studies have demonstrated that MPs cause intestinal toxicity, metabolic disruption, reproductive toxicity, neurotoxicity, immunotoxicity through oxidative stress, apoptosis and specific pathways, etc. Notably, in terms of combined effects with pollutants and neurotoxicity, the effects of MPs are still controversial. Future attention should be paid to the detection and quantification of MPs in human tissues, exploring the combined effects and related mechanisms of MPs with other pollutants and clarifying the association between MPs and the development of pre-existing diseases. Our work enhances further understanding of the potential health risks of MPs to terrestrial higher mammals.

Potential lifetime effects caused by cellular uptake of nanoplastics: A review

Plastics have been used for about 100 years, and daily-use products composed of plastics are now prevalent. As a result, humans are very easily exposed to the plastic particles generated from the daily-use plastics. However, studies on cellular uptake of nanoplastics in "human cells" have only recently begun to attract attention. In previous studies, definitions of nanoplastics and microplastics were vague, but recently, they have been considered to be different and are being studied separately. However, nanoplastics, unlike plastic particles of other sizes such as macro- and microplastics, can be absorbed by human cells, and thus can cause various risks such as cytotoxicity, inflammation, oxidative stress, and even diseases such as cancer^{82, 83.} and diabetes (Fan et al., 2022; Wang et al., 2023). Thus, in this review, we defined microplastics and nanoplastics to be different and described the potential risks of nanoplastics to human caused by cellular uptake according to their diverse factors. In addition, during and following plastic product usage a substantial number of fragments of different sizes can be generated, including nanoplastics. Fragmentation of microplastics into nanoplastics may also occur during ingestion and inhalation, which can potentially cause long-term hazards to human health. However, there are still few in vivo studies conducted on the health effect of nanoplastics ingestion and inhalation.

Polystyrene nanoplastics affect transcriptomic and epigenomic signatures of human fibroblasts and derived induced pluripotent stem cells: Implications for human health

Plastic pollution is increasing at an alarming rate yet the impact of this pollution on human health is poorly understood. Because human induced pluripotent stem cells (hiPSC) are frequently derived from dermal fibroblasts, these cells offer a powerful platform for the identification of molecular biomarkers of environmental pollution in human cells. Here, we describe a novel proof-of-concept for deriving hiPSC from human dermal fibroblasts deliberately exposed to polystyrene (PS) nanoplastic particles; unexposed hiPSC served as controls. In parallel, unexposed hiPSC were exposed to low and high concentrations of PS nanoparticles. Transcriptomic and epigenomic signatures of all fibroblasts and hiPSCs were defined using RNA-seq and whole genome methyl-seq, respectively. Both PS-treated fibroblasts and derived hiPSC showed alterations in expression of ESRRB and HNF1A genes and circuits involved in the pluripotency of stem cells, as well as in pathways involved in cancer, inflammatory disorders, gluconeogenesis, carbohydrate metabolism, innate immunity, and dopaminergic synapse. Similarly, the expression levels of identified key transcriptional and DNA methylation changes (DNMT3A, ESSRB, FAM133CP, HNF1A, SEPTIN7P8, and TTC34) were significantly affected in both PS-exposed fibroblasts and hiPSC. This study illustrates the power of human cellular models of environmental pollution to narrow down and prioritize the list of candidate molecular biomarkers of environmental pollution. This knowledge will facilitate the deciphering of the origins of environmental diseases.

Exposure to polyethylene microplastics alters immature gut microbiome in an infant in vitro gut model

Infants are characterized by an immaturity of the gut ecosystem and a high exposure to microplastics (MPs) through diet, dust and suckling. However, the bidirectional interactions between MPs and the immature infant intestinal microbiota remain unknown. Our study aims to investigate the impact of chronic exposure to polyethylene (PE) MPs on the gut microbiota and intestinal barrier of infants, using the new Toddler mucosal Artificial Colon coupled with a co-culture of epithelial and mucus-secreting cells. Gut microbiota composition was determined by 16S metabarcoding and microbial activities were evaluated by gas, short chain fatty acid and volatolomics analyses. Gut barrier integrity was assessed via evaluation of intestinal permeability, inflammation and mucus synthesis. Exposure to PE MPs induced gut microbial shifts increasing α-diversity and abundance of potentially harmful pathobionts, such as Dethiosulfovibrionaceae and Enterobacteriaceae. Those changes were associated to butyrate production decrease and major changes in volatile organic compounds profiles. In contrast, no significant impact of PE MPs on the gut barrier, as mediated by microbial metabolites, was reported. For the first time, this study indicates that ingestion of PE MPs can induce perturbations in the gut microbiome of infants. Next step would be to further investigate the potential vector effect of MPs.

Micro- and nanoplastics: A new cardiovascular risk factor?

Exposure to micro- and nanoplastics (MNPs) is inevitable due to their omnipresence in the environment. A growing body of studies has advanced our understanding of the potential toxicity of MNPs but knowledge gaps still exist regarding the adverse effects of MNPs on the cardiovascular system and underlying mechanisms, particularly in humans. Here, we reviewed up-to-date data published in the past 10 years on MNP-driven cardiovascular toxicity and mechanisms. Forty-six articles concerning ADME (absorption, distribution, and aggregation behaviors) and toxicity of MNPs in the circulatory system of animals and human cells were analyzed and summarized. The results showed that MNPs affected cardiac functions and caused toxicity on (micro)vascular sites. Direct cardiac toxicity of MNPs included abnormal heart rate, cardiac function impairment, pericardial edema, and myocardial fibrosis. On (micro)vascular sites, MNPs induced hemolysis, thrombosis, blood coagulation, and vascular endothelial damage. The main mechanisms included oxidative stress, inflammation, apoptosis, pyroptosis, and interaction between MNPs and multiple cellular components. Cardiovascular toxicity was determined by the properties (type, size, surface, and structure) of MNPs, exposure dose and duration, protein presence, the life stage, sex, and species of the tested organisms, as well as the interaction with other environmental contamination. The limited quantitative information on MNPs' ADME and the lack of guidelines for MNP cardiotoxicity testing makes risk assessment on cardiac health impossible. Furthermore, the future directions of cardiovascular research on MNPs are recommended to enable more realistic health risk assessment.

A review on microplastics and nanoplastics in the environment: Their occurrence, exposure routes, toxic studies, and potential effects on human health

Microplastics (MPs) and nanoplastics (NPs) are emerging environmental pollutants, having a major ecotoxicological concern to humans and many other biotas, especially aquatic animals. The physical and chemical compositions of MPs majorly determine their ecotoxicological risks. However, comprehensive knowledge about the exposure routes and toxic effects of MPs/NPs on animals and human health is not fully known. Here this review focuses on the potential exposure routes, human health impacts, and toxicity response of MPs/NPs on human health, through reviewing the literature on studies conducted in different in vitro and in vivo experiments on organisms, human cells, and the human experimental exposure models. The current literature review has highlighted ingestion, inhalation, and dermal contacts as major exposure routes of MPs/NPs. Further, oxidative stress, cytotoxicity, DNA damage, inflammation, immune response, neurotoxicity, metabolic disruption, and ultimately affecting digestive systems, immunology, respiratory systems, reproductive systems, and nervous systems, as serious health consequences.

Orally administered fluorescent nanosized polystyrene particles affect cell viability, hormonal and inflammatory profile, and behavior in treated mice

Commercially manufactured or generated through environmental degradation, microplastics (MPs) and nanoplastics (NPs) considerably contribute to environmental pollution. There is a knowledge gap in how exposure to MPs/NPs changes cellular function and affects animal and human health. Here, we demonstrate that after oral uptake, fluorescent polystyrene (PS) nanoparticles pass through the mouse digestive system, accumulate and aggregate in different organs, and induce functional changes in cells and organs. Using cochlear explant as a novel in vitro system, we confirmed the consequences of PS-MP/NP interaction with inner ear cells by detecting aggregates and hetero-aggregates of PS particles in hair cells. The testes of treated males accumulated MPs/NPs in the interstitial compartment surrounding the seminiferous tubules, which was associated with a statistically significant decrease in testosterone levels. Male mice showed increased secretion of interleukins (IL-12p35 and IL-23) by splenocytes while cyto- and genotoxicity tests indicated impaired cell viability and increased DNA damage in spleen tissue. Males also showed a broad range of anxiogenic responses to PS nanoparticles while hippocampal samples from treated females showed an increased expression of Bax and Nlrp3 genes, indicating a pro-apoptotic/proinflammatory effect of PS treatment. Taken together, induced PS effects are also gender-dependent, and therefore, strongly motivate future research to mitigate the deleterious effects of nanosized plastic particles.

Measurement of polystyrene photodegradation rate using a quartz crystal microbalance

Polystyrene is a very popular polymer utilised in the manufacture of various consumer products. This polymer is very cheap; however, after its usage, the slowness of its photodegradation leads to environmental pollution. In this report, the author presents a technique to systematically measure the rate of photodegradation of a thin polystyrene film. The said film was made to coat a quartz crystal microbalance (QCM) sensor. In order to detect polymer degradation and the reduction in the molecular weight, the resonance frequency of the sensor was monitored for 24 h. Results revealed that QCM sensor irradiation with ultraviolet light with a wavelength of 365 nm and optical power of 1.5 mW caused a quite significant change in the polymer structure.

Exposure to nanoplastics impairs collective contractility of neonatal cardiomyocytes under electrical synchronization

Nanoplastics are global pollutants that have been increasingly released into the environment following the degradation process of industrial and consumer products. These tiny particles have been reported to adversely affect various organs in the body, including the heart. Since it is probable that the less-developed hearts of newborn offspring are more vulnerable to nanoplastic insult during the infant feeding compared with mature hearts of adults, the acute effects of nanoplastics on the collective contractility of neonatal cardiomyocytes are to be elucidated. Here, we traced the aggregation of nanoplastics on the cell membrane and their internalization into the cytosol of neonatal rat ventricular myocytes (NRVMs) for 60 min in the presence of electrical pulses to synchronize the cardiac contraction in vitro. The time-coursed linkage of collective contraction forces, intracellular Ca²⁺ concentrations, mitochondrial membrane potentials, extracellular field potentials, and reactive oxygen species levels enabled us to build up the sequence of the cellular events associated with the detrimental effects of nanoplastics with positive surface charges on the immature cardiomyocytes. A significant decrease in intracellular Ca²⁺ levels and electrophysiological activities of NRVMs resulted in the reduction of contraction forces in the early phase (0-15 min). The further reduction of contraction force in the late phase (30-60 min) was attributed to remarkable decreases in mitochondrial membrane potentials and cellular metabolism. Our multifaceted assessments on the effect of positively surface charged nanoplastics on NRVM may offer better understanding of substantial risks of ever-increasing nanoplastic pollution in the hearts of human infants or adults.

Human Embryos, Induced Pluripotent Stem Cells, and Organoids: Models to Assess the Effects of Environmental Plastic Pollution

For a long time, animal models were used to mimic human biology and diseases. However, animal models are not an ideal solution due to numerous interspecies differences between humans and animals. New technologies, such as human-induced pluripotent stem cells and three-dimensional (3D) cultures such as organoids, represent promising solutions for replacing, refining, and reducing animal models. The capacity of organoids to differentiate, self-organize, and form specific, complex, biologically suitable structures makes them excellent in vitro models of development and disease pathogenesis, as well as drug-screening platforms. Despite significant potential health advantages, further studies and considerable nuances are necessary before their clinical use. This article summarizes the definition of embryoids, gastruloids, and organoids and clarifies their appliance as models for early development, diseases, environmental pollution, drug screening, and bioinformatics.

Genome-scale mechanistic modeling of signaling pathways made easy: A bioconductor/cytoscape/web server framework for the analysis of omic data

Genome-scale mechanistic models of pathways are gaining importance for genomic data interpretation because they provide a natural link between genotype measurements (transcriptomics or genomics data) and the phenotype of the cell (its functional behavior). Moreover, mechanistic models can be used to predict the potential effect of interventions, including drug inhibitions. Here, we present the implementation of a mechanistic model of cell signaling for the interpretation of transcriptomic data as an R/Bioconductor package, a Cytoscape plugin and a web tool with enhanced functionality which includes building interpretable predictors, estimation of the effect of perturbations and assessment of the effect of mutations in complex scenarios.

Nanoplastics as a Potential Environmental Health Factor: From Molecular Interaction to Altered Cellular Function and Human Diseases

The problem of plastic pollution is becoming increasingly important and has attracted great interest in the last few years. Polystyrene is one of the most used plastic types in the food and beverage industry, medical and laboratory devices. Increased plastic production and increased food, water, and air pollution and contact with nanoplastics may cause long-lasting changes and predispose to adverse developmental and degenerative diseases through mechanisms that are not yet understood.

The aim of this article is to provide an overview of current knowledge to plastics, especially polystyrene, and their impact on the human health. In particular, we discuss the major sources of plastic waste, polystyrene surface chemistry, as well as mechanisms by which plastics degrade in the environment. We also provide an insight into cellular uptake mechanism and the molecular interaction of polystyrene nanoparticles and human cells. This review offers scientists and clinicians useful information and could be used as a starting point for more in-depth analysis of nanoplastics as a potential environmental health factor.

Human pluripotent stem cells - Unique tools to decipher the effects of environmental and intracellular plastic pollution on human health

Increase in plastic pollution causes irreparable harm to the environment lasting for decades. While current data of plastic pollution include marine and terrestrial ecology, the impacts of degraded or intentionally produced microscopic-sized plastics on human health remain unknown. Here, we are proposing the usage of pluripotent stem cells, modern transcriptomics, and bioinformatics as a unique scientific tool to define the link between environmental and intracellular pollution, its outcome on early human development and origin of diseases. This commentary is an urgent appeal to the scientific and policy communities to invest more time and resources to establish reliable standards and methods to define and address the consequences of plastic pollution on human health.