The potential toxicity of microplastics on human health

Microplastics and orthodontic aligners: The concerns arising from the modernization of practice through polymers and plastics

Plastic aligners have transformed orthodontics, offering a discreet, comfortable, and aesthetically pleasing alternative to traditional fixed appliances. While they have advantages over fixed appliances, they come with environmental and health concerns due to the use of nonbiodegradable plastics, such as the leaching of Bisphenol-A (BPA) and microplastics that can impact human health directly through ingestion. Studies have shown that plastic aligners release microplastics during use, raising concerns about their potential health effects and environmental pollution. The potential health effects of ingested microplastics extend beyond gut microbiota disruption to impact various systems in the body. Research suggests that microplastic exposure can lead to respiratory complications, cardiovascular risks, and implications for brain health and cognitive function. The mechanisms of microplastic uptake into the body through inhalation, ingestion, and skin contact are essential for understanding how these particles interact with human tissues and organs. By prioritizing patient safety, responsible practices, and advancing scientific knowledge the orthodontic community can work towards mitigating the potential health impacts associated with microplastic exposure from aligners.

Exploring Oxidative Stress and Metabolic Dysregulation in Lung Tissues of Offspring Rats Exposed to Prenatal Polystyrene Microplastics: Effects of Melatonin Treatment

Metabolomics research provides a clearer understanding of an organism's metabolic state and enables a more accurate representation of its functional performance. This study aimed to investigate changes in the metabolome of lung tissues resulting from prenatal exposure to polystyrene microplastics (PS-MPs) and to understand the underlying mechanisms of lung damage in rat offspring. We conducted metabolomic analyses of lung tissue from seven-day-old rat pups exposed to prenatal PS-MPs. Our findings revealed that prenatal exposure to PS-MPs led to significantly increased oxidative stress in lung tissues, characterized by notable imbalances in nucleic acid metabolism and altered profiles of specific amino acids. Furthermore, we evaluated the therapeutic effects of melatonin treatment on lung function in 120-day-old offspring and found that melatonin treatment significantly improved lung function and histologic change in the affected offspring. This study provides valuable biological insights into the mechanisms underlying lung damage caused by prenatal PS-MPs exposure. Future studies should focus on validating the results of animal experiments in humans, exploring additional therapeutic mechanisms of melatonin, and developing suitable protocols for clinical use.

Gradient columns to measure the density of microplastics

Density gradient columns are an established industrial method for measuring the density of plastics, but have rarely been applied to environmental plastics. In this study 14 density gradient columns were used to measure the density of 150 environmental plastics particles from an urban beach, plus 100 microplastics of known identity, representing what is believed to be the most extensive density dataset for environmental plastic debris available in scientific literature. In total, 92 % of investigated particles had their density measured, with the remainder falling outside of the range of the density columns: 800-1418 kg·m-3. Error values for individual plastic particles were conservatively estimated as ≤0.27 kg·m-3, equating to the density difference associated with a distance of 1 mm in the density gradient column. Moreover, error values for plastics of known identity, based on the standard deviation of five different particles of the same polymer type, were generally low, ≤± 1.78 kg·m-3 for 75 % of polymers. The most notable exception was crumb rubber from used tyres, with a density of 1204.84 ± 105.87 kg·m-3, reflecting a heterogenous material. The majority of environmental plastics were polyethylene pellets, with densities from 823.47 to 1143.47 kg·m-3, a much wider range than reported in literature for this polymer. The densest environmental pellet was biologically attached to a stone-like particle. Otherwise, there was no evidence that environmental processing, in the form of biofilm growth or weathering, was driving variability in density. Most pellets with extremely high or low density were coloured, indicating that additives or impurities introduced during manufacturing altered the density of the virgin resin. Overall, density gradient columns show great promise for improving our knowledge of microplastic density. They represent an accurate and efficient high-throughput method, which can measure the density of ∼40 microplastics simultaneously over relatively short time periods.

Recent advances on transport and transformation mechanism of nanoplastics in lung cells

Microplastics (MPs) are solid plastic particles less than or equal to 5 mm in size that are insoluble in water, and when the diameter is further reduced to <1 micrometer (μm), we call them nanoplastics (NPs). MPs and NPs are widely present in the atmosphere, and plastic particles have also been detected in the sputum of patients with respiratory diseases. This warns us that these tiny plastic particles are a potential threat to human respiratory health. The lungs, as the main organs of the respiratory system, are more likely to be adversely affected by inhaled NPs. However, the mechanism of transport and transformation of NPs in the lung is not clear, so our review mainly focuses on a series of effects and mechanisms of NPs on lung cells through absorption, distribution, metabolism, excretion (ADME) after inhalation into the human body. The most commonly used models in these experimental studies we focus on are A549 and BEAS-2B cells, which are used to model the lung cell response to plastic particles. In addition, we also summarize some shortcomings of these experiments and prospects for future studies, hoping to provide further clues for future studies and contribute to the prevention of related hazards and diseases.

Environmental Contaminants in Fish Products: Food Safety Issues and Remediation Strategies

The intentional or accidental presence of environmental contaminants, such as persistent organic pollutants, metals, and microplastics, can harm the aquatic ecosystem and their living organisms, as well as consumers of seafood. This study provides an overview of marine pollution caused by various chemicals and their toxicity to both the environment and humans. In addition to regulatory limits established for some contaminants, monitoring and management policies should mandate activities such as bioremediation and the use of carbon-based composite photocatalysts to reduce or eliminate these compounds.

Presence of microplastics in human stomachs

This study presents the first definitive confirmation of microplastic presence in the human stomach, based on samples from 26 cadavers. 97 microplastic particles were extracted from stomach contents, across all 26 individuals, revealing a universal prevalence of microplastics in the cadavers. Morphological analysis of the extracted particles unveiled distinct shapes, with fibers constituting the majority (52.04 %), followed by fragments (39.80 %) and films (8.16 %). The average quantity of microplastics per individual was calculated to be 9.4 ± 10.4 particles, with an estimated daily intake of microplastics at 32.2 particles per day. These figures are lower than estimates derived from both daily microplastic consumption alone and notably, those calculated from stool analyses. Our study also suggests that the breakdown or transformation of microplastics cannot be ruled out during their passage through the digestive tract. Although the number of microplastics in stomach contents reported in this study was even lower than the daily microplastic intake rates reported in the literature, it provides conclusive evidence for the presence of microplastics in the human stomach and provides important preliminary data in terms of the risks that may arise for human health.

Micro/nano plastics in the urinary system: Pathways, mechanisms, and health risks

Micro/Nano plastics (MNPs) pollutants are widespread in the environment, raising significant concerns about their biosafety. Emerging studies indicate that the urinary system is a primary accumulation site for MNPs, leading to severe tissue and functional damage. This review aims to summarize recent research on the potential hazards that MNPs may pose to the urinary system, highlighting the mechanisms of toxicity and the current state of knowledge. Studies have shown that MNPs enter the human body through drinking water, the food chain, inhalation, and skin contact. They may penetrate the bloodstream via the digestive, respiratory, and skin systems, subsequently dispersing to various organs, including the urinary system. The potential accumulation of MNPs in the urinary system might induce cellular oxidative stress, inflammation, apoptosis, autophagy, the "intestine-kidney axis", and other possible toxic mechanisms. These processes could disrupt kidney metabolic functions and promote tissue fibrosis, thereby potentially increasing the risk of urinary system diseases. Despite ongoing research, the understanding of MNPs' impact on the urinary system remains limited. Therefore, this review provides a comprehensive overview of MNPs' potential toxicity mechanisms in the urinary system, highlights key challenges, and outlines future research directions. It offers a theoretical basis for the development of effective protective measures and policies.

Microplastics from face masks: Unraveling combined toxicity with environmental hazards and their impacts on food safety

Microplastics (MPs) refer to tiny plastic particles, typically smaller than 5 mm in size. Due to increased mask usage during COVID-19, improper disposal has led to masks entering the environment and releasing MPs into the surroundings. MPs can absorb environmental hazards and transfer them to humans and animals via the food chain, yet their impacts on food safety and human health are largely neglected. This review summarizes the release process of MPs from face masks, influencing factors, and impacts on food safety. Highlights are given to the prevalence of MPs and their combined toxicities with other environmental hazards. Control strategies are also explored. The release of MPs from face masks is affected by environmental factors like pH, UV light, temperature, ionic strength, and weathering. Due to the chemical active surface and large surface area, MPs can act as vectors for heavy metals, toxins, pesticides, antibiotics and antibiotic resistance genes, and foodborne pathogens through different mechanisms, such as electrostatic interaction, precipitation, and bioaccumulation. After being adsorbed by MPs, the toxicity of these environmental hazards, such as oxidative stress, cell apoptosis, and disruption of metabolic energy levels, can be magnified. However, there is a lack of comprehensive research on both the combined toxicities of MPs and environmental hazards, as well as their corresponding control strategies. Future research should prioritize understanding the interaction of MPs with other hazards in the food chain, their combined toxicity, and integrating MPs detection and degradation methods with other hazards.

Periconceptional maternal intake of ultra-processed foods, energy and macronutrients the impact on imaging markers of early utero-placental vascular development: The rotterdam periconception cohort

BACKGROUND & AIMS

The quantity and quality of maternal nutrition in the periconception period is an important determinant for embryonic and foetal development and subsequent pregnancy course and outcome. The intake of ultra-processed foods (UPF) has increased worldwide and adverse health outcomes have been reported. However, the impact of UPF intake on the placenta, essential for prenatal nourishment, is unknown. Therefore, we aim to investigate associations between the periconceptional maternal intake of UPF, energy and related macronutrients, and first-trimester utero-placental vascular development.

METHODS

We included 214 ongoing pregnancies in the Virtual Placenta study, a subcohort of the Rotterdam periconception cohort. At enrollment, participants filled out a food frequency questionnaire from which we calculated the average daily energy from UPF, total energy intake and macronutrient intake from UPF. At 7-9-11 weeks of gestation, we performed sequential three-dimensional power Doppler ultrasounds of the first-trimester utero-placental vasculature. Virtual Organ Computer-aided AnaLysis (VOCAL) software, Virtual Reality segmentation and a skeletonization algorithm were applied to measure placental volume (PV), utero-placental vascular volume (uPVV) and generate the utero-placental vascular skeleton (uPVS). Absolute vascular morphology was quantified by assigning a morphologic characteristic to each voxel in the uPVS (end-, bifurcation-, crossing- or vessel point) and used to calculate density of vascular branching. Linear mixed models adjusted for confounders were used to investigate associations between maternal intake of UPF, total energy and macronutrients from UPF and PV, uPVV and uPVS characteristics.

RESULTS

Energy intake from UPF and total energy intake were not consistently associated with imaging markers of utero-placental vascular development. Higher carbohydrate intake of 10 g/day from UPF was associated with increased uPVS trajectories (end points (β = 0.34, 95%CI = 0.07; 0.61), bifurcation points (β = 0.38, 95%CI = 0.05; 0.70), vessel points (β = 0.957, 95%CI = 0.21; 1.71). No associations were observed with PV.

CONCLUSIONS

Against our hypothesis, periconceptional maternal intake of UPF and total energy were not convincingly associated with impaired first-trimester utero-placental vascular development. Remarkably, the increased intake of carbohydrates from UPF, which is often considered 'unhealthy', is positively associated with first-trimester utero-placental vascular development. Given the complexity of diet, further research should elucidate what underlies these findings to be able to interpret how nutrition may impact utero-placental vascular development in early pregnancy.

CLINICAL TRIAL NUMBER

This study is registered at the Dutch Trial Register (NTR6854).

Integrated transcriptomics and metabolomics reveal the mechanism of polystyrene nanoplastics toxicity to mice

Microplastic (MP) are an emerging environmental pollutant, which has toxic effects on organisms, and it has received extensive attention currently. Studying the transcriptomic and metabolic responses of mice to nanoplastic-contaminated water is critical for understanding molecular-level toxicity of nanoplastics (NPs), but there are few studies on this topic. To analyze the effects of different concentrations of polystyrene (PS) nanoplastic-contaminated water on mice at the transcriptome and metabolism of spleens to study the molecular toxicity. Here, testing of histopathology of spleen of female mice was performed after drinking water containing 0.1 μm PS-NPs (1 mg/mL and 50 mg/mL) at different concentrations for 49 days, respectively. The spleen tissue samples were subjected to metabolome and transcriptome sequencing. Four differentially expressed genes were randomly chosen for qRT-PCR to confirm the correctness of transcriptome sequencing. Common Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis showed that a large number of differential genes and differential metabolites mainly focused on immune, inflammation, neurodegenerative disease, cardiovascular disease, nervous, etc. in the organism systems module; lipid, amino acid, taurine and hypotaurine metabolisms, etc. in the metabolism module; signaling translation, signaling molecules and interaction, and neuroactive ligand-receptor interaction, etc. in the environmental information processing. The results showed that pathway analysis at transcriptome and metabolome levels confirmed that the immune system of mice was affected after drinking water contaminated with polystyrene nanoplastics.

Raman microspectroscopy and laser-induced breakdown spectroscopy for the analysis of polyethylene microplastics in human soft tissues

People are exposed to microplastics (MPs) on a large scale in everyday life. However, it is not clear whether MPs can also be distributed and retained in certain tissues. Therefore, the development of analytical methods capable of detecting MPs in specific human organs/tissues is of utmost importance. In this study, the use and combination of spectroscopic techniques, namely Raman microspectroscopy and laser-induced breakdown spectroscopy (LIBS), was tested for the detection of polyethylene (PE) MPs in human tonsils. Preliminary results showed that Raman microspectroscopy was able to detect MPs down to 1 μm in size and LIBS down to 10 μm. In the next step, human tonsils were spiked with PE MPs, and digested. The filtered particles were analyzed using Raman microspectroscopy and LIBS, and complemented by X-ray fluorescence (XRF). The results showed that Raman microspectroscopy could reliably detect PE MPs in spiked human tonsils, while LIBS and XRF served as a reference analytical method to characterize particles that could not be classified by Raman microspectroscopy for their non-organic origin. The results of this study, supported by a current feasibility study conducted on clinical samples, demonstrated the reliability and feasibility of this approach for monitoring MPs in biotic samples.

Convenient determination of polystyrene microplastics in soils by gel permeation chromatography-ultraviolet detection analysis

Microplastics (MPs), especially polystyrene microplastics (PS-MPs), have emerged a new worldwide pollutant, prompting significant public concern regarding their detection in environmental media. Analysis of PS-MPs in soil remains as a challenging task for analysts due to the highly intricate matrices. This work presents a practical approach for detecting PS-MPs in soil, which involves dilute HCl-assisted extraction and gel permeation chromatography- ultraviolet detection (GPC-UV) analysis. The presence of MPs in soil was confirmed through the use of a scanning electron microscope in conjunction with energy dispersive spectroscopy investigation. PS-MPs was isolated from soil, by agitating it with a diluted HCl solution, filtering the resulting liquid, and dissolving the residue on the filter with THF. The extractant was subsequently determined by GPC-UV. The introduction of a small amount of HCl into the extraction system was found to greatly expedite the settling of soil in water and enhance the efficacy of extracting PS-MPs in about 30 min. The linear range of PS-MPs was from 1.0 to 100 μg/mL with R2 > 0.999. Good reproducibility was obtained with the intra-day relative standard deviation (RSD, n = 3) of 1.36 % and the inter-day RSD (n = 3) of 4.78 %. The concentration of PS-MPs in soil samples were N.D. - 2.33 μg/g, and the good recoveries were 76.7-100.3 %. The corresponding AFGEEprer score was calculated to be 0.59, indicating the concept of green analytical chemistry for the pretreatment method. These results indicated that this method has a powerful potential for the accurate and rapid determination of PS-MPs in soil.

Micro/Nanoplastic Exposure on Placental Health and Adverse Pregnancy Risks: Novel Assessment System Based upon Targeted Risk Assessment Environmental Chemicals Strategy

Micro/nanoplastics (MNPs), as emerging pollutants, have been detected in both the maternal and fetal sides of the placenta in pregnant women, and their reproductive toxicity has been demonstrated in in vivo and in vitro experimental models. The Targeted Risk Assessment of Environmental Chemicals (TRAEC) strategy has been innovatively devised to facilitate valid risk assessment, encompassing a comprehensive evaluation of reliability, correlation, outcome fitness, and integrity across four dimensions based on the included published evidence and our own findings. This study serves as an application case of TRAEC, with 40 items of research evidence on the toxicity of MNPs to the placenta, which were rigorously screened and incorporated into the final scoring system. The final score for this TRAEC case study is 5.63, suggesting a moderate-to-low risk of reproductive toxicity associated with MNPs in the placenta, which may potentially increase with decreasing particle size. It is essential to emphasize that the findings also report original data from assays indicating that exposure to high-dose groups (100 μg/mL, 200 μg/mL) of 50 nm and 200 nm polystyrene nanoplastics (PS-NPs) induces HTR8/SVneo cell cycle arrest and cell apoptosis, which lead to reproductive toxicity in the placenta by disrupting mitochondrial function. Overall, this study employed the TRAEC strategy to provide comprehensive insight into the potential reproductive health effects of ubiquitous MNPs.

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

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

Long-term polystyrene nanoparticles exposure reduces electroretinal responses and exacerbates retinal degeneration induced by light exposure

The impact of plastic pollution on living organisms have gained significant research attention. However, the effects of nanoplastics (NPs) on retina remain unclear. This study aimed to investigate the effect of long-term polystyrene nanoparticles (PS-NPs) exposure on mouse retina. Eight weeks old C57BL/6 J mice were exposed to PS-NPs at the diameter of 100 nm and concentration of 10 mg/L in drinking water for 3 months. PS-NPs were able to penetrate the blood-retina barrier, accumulated at retinal tissue, caused increased oxidative stress level and reduced scotopic electroretinal responses without remarkable structural damage. PS-NPs exposure caused cytotoxicity and reactive oxygen species accumulation in cultured photoreceptor cell. PS-NPs exposure increased oxidative stress level in retinal pigment epithelial (RPE) cells, leading to changes of gene and protein expression indicative of compromised phagocytic activity and cell junction formation. Long-term PS-NPs exposure also aggravated light-induced photoreceptor cell degeneration and retinal inflammation. The transcriptomic profile of PS-NPs-exposed, light-challenged retinal tissue shared similar features with those of age-related macular degeneration (AMD) patients in the activation of complement-mediated phagocytic and proinflammatory responses. Collectively, these findings demonstrated the oxidative stress- and inflammation-mediated detrimental effect of PS-NPs on retinal function, suggested that long-term PS-NPs exposure could be an environmental risk factor contributing to retinal degeneration.

Transitioning to Microplastic-Free Seed Coatings: Challenges and Solutions

This review addresses the issue of replacing manufactured microplastics in seed coatings used in agriculture. Firstly, it focuses on the policy and regulatory actions taken on microplastics at a global level. There is no consensus within the scientific community on the definition of a microplastic and, more generally, on the classification of plastic debris. Nevertheless, several decision schemes have been proposed in an attempt to define the notion of microplastics. The different criteria relevant to this definition, such as the size, physical state, chemical structure, origin, and persistence of microplastics, are discussed, with a comparison being made between the REACH regulation and the scientific literature. Seed production and processing are also discussed, with the functions of seed coatings being explained in order to gain a better understanding of the properties to be considered in a substitution strategy for currently used microplastics. The main challenges are multiple; substitutes must provide the same performance as microplastics: (i) improving the adherence of the treatment to the seed, (ii) distributing the treatment more evenly over the seed, (iii) reducing the amount of dust-off when handling treated seed, and (iv) improving the seed flowability, which is particularly important during the sowing stage, all while preserving the physiological properties of the seed. Substitute polymers are proposed according to the desired performance and functional properties: two main chemical families of biopolymers were identified in the literature: polysaccharides and proteins. Among them, 13 and 6 polymers, respectively, complied with REACH regulation, demonstrating adhesion, dust reduction performances, and preservation of seed physiological quality in particular. This work aims to guide future studies on microplastic substitution in seed coatings, and to highlight research needs in this area. It is based on an analysis and discussion of the literature, identifying and listing potential substitutes.

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.

Probabilistic Estimation of Airborne Micro- and Nanoplastic Intake in Humans

Little research exists on the magnitude, variability, and uncertainty of human exposure to airborne micro- and nanoplastics (AMNPs), despite their critical role in human exposure to MNPs. We probabilistically estimate the global intake of AMNPs through three main pathways: indoor inhalation, outdoor inhalation, and ingestion during indoor meals, for both children and adults. The median inhalation of AMPs is 1,207.7 (90% CI, 42.5-8.48 × 104) and 1,354.7 (90% CI, 47.4-9.55 × 104) N/capita/day for children and adults, respectively. The annual intake of AMPs is 13.18 mg/capita/a for children and 19.10 mg/capita/a for adults, which is approximately one-fifth and one-third of the mass of a standard stamp, assuming a consistent daily intake of medians. The majority of AMP number intake occurs through inhalation, while the ingestion of deposited AMPs during meals contributes the most in terms of mass. Furthermore, the median ANP intake through outdoor inhalation is 9,638.1 N/day (8.23 × 10-6 μg/d) and 5,410.6 N/day (4.62 × 10-6 μg/d) for children and adults, respectively, compared to 5.30 × 105 N/day (5.79 × 10-4 μg/d) and 6.00 × 105 N/day (6.55 × 10-4 μg/d) via indoor inhalation. Considering the increased toxicity of smaller MNPs, the significant number of ANPs inhaled warrants great attention. Collaborative efforts are imperative to further elucidate and combat the current MPN risks.

Dynamic Stomach Model-Capillary Electrophoresis-ICPMS for Evaluation of Release and Transformation Behaviors of Arsenic Species from Microplastics during Digestion

Microplastics (MPs) can act as carriers of environmental arsenic species into the stomach with food and release arsenic species during digestion, which threatens human health. Herein, an integrated dynamic stomach model (DSM)-capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICPMS) is developed for online monitoring of the release and transformation behaviors of arsenic species loaded on MPs (As-MPs) in the simulated human stomach. The 3D-printed DSM with a soft stomach chamber enables the behaviors of gastric peristalsis, gastric and salivary fluid addition, pH adjustment, and gastric emptying (GE) to be controlled by a self-written program after oral ingestion of food with As-MPs. The gastric extract during digestion is introduced into the spiral channel to remove the large particulate impurity and online filtered to obtain the clarified arsenic-containing solution for subsequent speciation analysis of arsenic by CE-ICPMS. The digestion conditions and pretreatment processes of DSM are tracked and validated, and the release rates of As-MPs digested by DSM are compared with those digested by the static stomach model and DSM without GE. The release rate of inorganic arsenic on MPs is higher than that of organic arsenic throughout the gastric digestion process, and 8% of As(V) is reduced to As(III). The detection limits for As(III), DMA, MMA, and As(V) are 0.5-0.9 μg L-1 using DSM-CE-ICPMS, along with precisions of ≤8%. This present method provides an integrated and convenient tool for evaluating the release and transformation of As-MPs during human gastric digestion and provides a reference for exploring the interactions between MPs and metals/metalloids in the human body.

Important Factors Affecting Induction of Cell Death, Oxidative Stress and DNA Damage by Nano- and Microplastic Particles In Vitro

We have described the influence of selected factors that increase the toxicity of nanoplastics (NPs) and microplastics (MPs) with regard to cell viability, various types of cell death, reactive oxygen species (ROS) induction, and genotoxicity. These factors include plastic particle size (NPs/MPs), zeta potential, exposure time, concentration, functionalization, and the influence of environmental factors and cell type. Studies have unequivocally shown that smaller plastic particles are more cytotoxic, penetrate cells more easily, increase ROS formation, and induce oxidative damage to proteins, lipids, and DNA. The toxic effects also increase with concentration and incubation time. NPs with positive zeta potential are also more toxic than those with a negative zeta potential because the cells are negatively charged, inducing stronger interactions. The deleterious effects of NPs and MPs are increased by functionalization with anionic or carboxyl groups, due to greater interaction with cell membrane components. Cationic NPs/MPs are particularly toxic due to their greater cellular uptake and/or their effects on cells and lysosomal membranes. The effects of polystyrene (PS) vary from one cell type to another, and normal cells are more sensitive to NPs than cancerous ones. The toxicity of NPs/MPs can be enhanced by environmental factors, including UV radiation, as they cause the particles to shrink and change their shape, which is a particularly important consideration when working with environmentally-changed NPs/MPs. In summary, the cytotoxicity, oxidative properties, and genotoxicity of plastic particles depends on their concentration, duration of action, and cell type. Also, NPs/MPs with a smaller diameter and positive zeta potential, and those exposed to UV and functionalized with amino groups, demonstrate higher toxicity than larger, non-functionalized and environmentally-unchanged particles with a negative zeta potential.