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.

Nanoplastics Penetrate Human Bronchial Smooth Muscle and Small Airway Epithelial Cells and Affect Mitochondrial Metabolism.

Micro- and nanoplastic particles, including common forms like polyethylene and polystyrene, have been identified as relevant pollutants, potentially causing health problems in living organisms. The mechanisms at the cellular level largely remain to be elucidated. This study aims to visualize nanoplastics in bronchial smooth muscle (BSMC) and small airway epithelial cells (SAEC), and to assess the impact on mitochondrial metabolism. Healthy and asthmatic human BSMC and SAEC in vitro cultures were stimulated with polystyrene nanoplastics (PS-NPs) of 25 or 50 nm size, for 1 or 24 h. Live cell, label-free imaging by holotomography microscopy and mitochondrial respiration and glycolysis assessment were performed. Furthermore, 25 and 50 nm NPs were shown to penetrate SAEC, along with healthy and diseased BSMC, and they impaired bioenergetics and induce mitochondrial dysfunction compared to cells not treated with NPs, including changes in oxygen consumption rate and extracellular acidification rate. NPs pose a serious threat to human health by penetrating airway tissues and cells, and affecting both oxidative and glycolytic metabolism.

The first reported values of microplastics in prostate.

BACKGROUND: Microplastics are ubiquitous, widespread environmental pollutants with unavoidable human exposure. Herein, it was aimed to investigate the presence of microplastics in prostate tissue. METHODS: Prostate tissues from 12 patients who underwent Trans Urethral Resection of the Prostate (TUR-P) were analyzed to investigate the presence of microplastics. Initially, the prostate tissues were analyzed for microplastic particles using a light microscope after extraction. Subsequently, the chemical composition of the particles found in the prostate tissues was characterized using Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectrophotometry. RESULTS: Microplastic particles of various types were detected in 6 out of 12 patients. All detected plastic particles in this study were microplastics, with sizes below 26 µm in size. These microplastics exhibited different shapes as pellets, spheres or fibers. Overall, among the 12 analyzed prostate tissue samples, four different types of plastic were identified in six samples. The most common type of microplastic detected was Polyamide (Nylon 6), found in samples from three patients. Other detected types, Polypropylene, Polyacrylic Acid and Poly (dimethylsiloxane) were each determined in samples from one patient. CONCLUSIONS: This is the first study to demonstrate the presence of microplastics in prostate tissue, serving as an exploratory investigation, which can trigger further research to validate the results in a larger patient cohort.

Microplastic Pollution in High Population Density Zones of Selected Rivers from Southeast Asia.

Southeast Asia (SEA) faces significant environmental challenges due to rapid population growth and economic activity. Rivers in the region are major sources of plastic waste in oceans. Concerns about their contribution have grown, but knowledge of microplastics in the area is still limited. This article compares microplastic levels in sediment and water from urban zones of three major rivers in SEA: Chao Phraya River (Thailand), Saigon River (Vietnam), and Citarum River (Indonesia). The study reveals that in all three rivers, microplastics were found, with the highest concentrations in Chao Phraya's water (80 ± 60 items/m3) and Saigon's sediment (9167 ± 4559 items/kg). The variations in microplastic sizes and concentrations among these rivers may be attributed to environmental factors and the exposure duration of plastic to the environment. Since these rivers are important water supply sources, rigorous land-use regulations and raising public awareness are crucial to mitigate plastic and microplastic pollution.

An assessment of microplastic contamination in beach sediment of Maharashtra State, India, with special reference to anthropogenic activities.

The escalating issue of microplastic (MP) pollution poses a significant threat to the marine environment due to increasing plastic production and improper waste management. The current investigation was aimed at quantifying the MP concentration on 25 beaches on the Maharashtra coast, India. Beach sediments (1 kg) were collected from each site, with five replicates to evaluate the extent of MPs. The samples were homogenized, and three 20 g replicas were prepared for subsequent analysis. Later, the samples were sieved, and MPs were extracted using previously published protocols. The abundance of MPs found as 1.56 ± 0.79 MPs/g, ranges from 0.43 ± 0.07 to 3 ± 0.37 MPs/g. Fibers were found as the most abundant shape of MPs. Size-wise classification revealed dominance of <1 mm and 1-2 mm-sized MPs. Blue- and black-colored MPs were recorded dominantly. Polymer identification of MPs revealed polyurethane, polypropylene, polyvinyl chloride, acrylic or polymethyl methacrylate, and rubber. The findings revealed that MPs were found to be higher at highly impacted sites, followed by moderately impacted sites and low-impacted sites, possibly due to a different degree of anthropogenic pressure. The study recommended the urgent need for effective policy to prevent plastics accumulation in the coastal environment of Maharashtra State, India. PRACTITIONER POINTS: The study investigated the abundance and distribution of microplastics in the marine environment, specifically in sediments. The most common type of microplastic found was fibers, followed by fragments and films. Microplastics were found to pose a potential risk to the marine ecosystem, although further research is needed to fully understand their ecological impact. Future research should focus on expanding the sample size, assessing long-term effects, exploring sources and pathways, and considering size and shape of microplastics. The findings recommended urgent action to mitigate plastic pollution in Maharashtra coast.

A systematic review on microplastic contamination in marine Crustacea and Mollusca of Asia: Current scenario, concentration, characterization, polymeric risk assessment, and future Prospectives.

Microplastics (MPs) pollution has wreaked havoc on biodiversity and food safety globally. The false ingestion of MPs causes harmful effects on organisms, resulting in a decline in biodiversity. The present review comprehended the current knowledge of MP contamination in Crustacea and Mollusca from 75 peer-reviewed articles published in Asia between 2015 and 2023. A total of 79 species (27 Crustacea and 52 Mollusca) have been recorded to be contaminated with MPs. Out of the total 27 species of Crustacea, Metopograpsus quadridentatus (327.56 MPs/individual) and Balanus albicostatus (0.42 MPs/individual) showed the highest and lowest contamination, respectively. Out of the total 52 species of Mollusca, Dolabella auricularia (2325 MPs/individual) and Crassostrea gigas and Mytilus edulis (0.2 MPs/individual) showed the highest and lowest contamination, respectively. In terms of country-wise MP contamination, China has the highest number of contaminated species in both phylums among Asia. Findings of pollution indices revealed a very high risk of MP contamination in all the countries. Fiber was reported predominantly in both groups. Blue and black-colored MPs having <500 µm and <500 µm-1 mm size were found dominantly in Crustacea and Mollusca, respectively. Polypropylene was recorded as the dominant plastic polymer in both Crustacea and Mollusca. In essence, this review has provided a comprehensive insight into MP concentration in Crustacea and Mollusca of Asia, highlighting variations among species and geographic locations. This understanding is crucial for tackling urgent environmental challenges, safeguarding human health, and promoting global sustainability initiatives amid the escalating issue of plastic pollution. PRACTITIONER POINTS: Microplastic pollution has created havoc on biodiversity and food safety. A total of 27 and 52 species of crustaceans and Mollusca have been recorded to be contaminated with MPs. Metopograpsus quadridentate and Dolabella auricularia have shown higher MPs contamination. Polypropylene was recorded as the dominant plastic polymer in both crustacean and Mollusca. Findings of pollution indices revealed a very high risk of MP contamination in all the countries.

Anthropogenic particle abundance and characteristics in seawater and intertidal sediments of the Tonkin Bay Coast (North Vietnam).

Microplastics (MPs, plastic items from 1 µm to 5 mm in size) are present in all environmental compartments. The evaluation of their concentration, fate, and spatial distribution is still a challenge for the scientific community. This concern is just debuting in developing countries, (i.e., Asia, South America, and Africa). This study deals with the MP contamination in the abiotic marine compartments of Northern Vietnam: seawater and intertidal sediments. Four sites located in the intertidal zone or near the coastline in Tonkin Bay, Vietnam were studied. A total of 16 samples (eight for each compartment) were collected in July 2020 (rainy season) and January 2021 (dry season). Anthropogenic particles (total observed fibers and fragments) were found at levels ranging from 3 to 303 particles/m3 in seawater and from 63 to 955 particles/kg dry weight in sediments. Most of these were fibers less than 300-µm long. Higher levels of seawater at the Nam Dinh site were found in the rainy season compared to the dry one. As the river flow was estimated six times higher during the rainy season than during the dry season, these results suggest the river discharge is a potential source of contamination for the coastal zone. The temporal variability was lower for the sediments than for the seawater, suggesting the long-term integration of the anthropogenic particles in this compartment. A small portion of sorted particles were analyzed by µFTIR (8.35%), and this sub-sample was only composed of fragments. Still, fragments were mostly composed of polypropylene (PP, 82%), polyethylene (PE, 9%), and polystyrene (PS, 9%). The fragment size was similar in the two studied compartments, but it was dependent on polymer types since PS fragments (140 ± 17 µm) were smaller than those made of PE (622 ± 123 µm) and PP (869 ± 905 µm). Future works should investigate the smallest fraction of MP (even nanoplastics) as well as find solutions in order to mitigate MP contamination in the marine environment.

Enhanced biotoxicity by co-exposure of aged polystyrene and ciprofloxacin: the adsorption and its influence factors.

Microplastics (MPs), as emerging contaminants, usually experience aging processes in natural environments and further affect their interactions with coexisted contaminants, resulting in unpredictable ecological risks. Herein, the effect of MPs aging on their adsorption for coexisting antibiotics and their joint biotoxicity have been investigated. Results showed that the adsorption capacity of aged polystyrene (PS, 100 d and 50 d) for ciprofloxacin (CIP) was 1.10-4.09 times higher than virgin PS due to the larger BET surface area and increased oxygen-containing functional groups of aged PS. Following the increased adsorption capacity of aged PS, the joint toxicity of aged PS and CIP to Shewanella Oneidensis MR-1 (MR-1) was 1.03-1.34 times higher than virgin PS and CIP. Combined with the adsorption process, CIP posed higher toxicity to MR-1 compared to aged PS due to the rapid adsorption of aged PS for CIP in the first 12 h. After that, the adsorption process tended to be gentle and hence the joint toxicity to MR-1 was gradually dominated by aged PS. A similar transformation between the adsorption rate and the joint toxicity of PS and CIP was observed under different conditions. This study supplied a novel perception of the synergistic effects of PS aging and CIP on ecological health.

Effect of conventional and biodegradable microplastics on earthworms during vermicomposting process.

The potential effect of microplastics is an increasingly growing environmental issue. However, very little is known regarding the impact of microplastics on the vermicomposting process. The present study explored the effect of non-biodegradable (low density polyethylene; LDPE) and biodegradable (polybutylene succinate-co-adipate; PBSA) microplastics on earthworm Eisenia fetida during vermicomposting of cow dung. For this, earthworms were exposed to different concentrations (0, 0.5, 1 and 2%) of LDPE and PBSA of 2 mm size. The cow dung supported the growth and hatchlings of earthworms, and the toxicity effect of both LDPE and PBSA microplastics on Eisenia fetida was analyzed. Microplastics decreased the body weight of earthworms and there was no impact on hatchlings. The body weight of earthworm decreased from 0 to 60th day by 18.18% in 0.5% of LDPE treatment, 5.42% in 1% of LDPE, 20.58% in 2% of LDPE, 19.99% in 0.5% of PBSA, 15.09% in 1% of PBSA and 16.36% in 2% of PBSA. The physico-chemical parameters [pH (8.55-8.66), electrical conductivity (0.93-1.02 (S/m), organic matter (77.6-75.8%), total nitrogen (3.95-4.25 mg/kg) and total phosphorus (1.16-1.22 mg/kg)] do not show much significant changes with varying microplastics concentrations. Results of SEM and FTIR-ATR analysis observed the surface damage of earthworms, morphological and biochemical changes at higher concentrations of both LDPE and PBSA. The findings of the present study contribute to a better understanding of microplastics in vermicomposting system.

Combined effects of micron-sized polyvinyl chloride particles and copper on seed germination of perilla.

Microplastics (MPs) and copper (Cu) pollution coexist widely in cultivation environment. In this paper, polyvinyl chloride (PVC) were used to simulate the MPs exposure environment, and the combined effects of MPs + Cu on the germination of perilla seeds were analyzed. The results showed that low concentrations of Cu promoted seed germination, while medium to high concentrations exhibited inhibition and deteriorated the morphology of germinated seeds. The germination potential, germination index and vitality index of 8 mg • L-1 Cu treatment group with were 23.08%, 76.32% and 65.65%, respectively, of the control group. The addition of low concentration PVC increased the above indicators by 1.27, 1.15, and 1.35 times, respectively, while high concentration addition led to a decrease of 65.38%, 82.5%, and 66.44%, respectively. The addition of low concentration PVC reduced the amount of PVC attached to radicle. There was no significant change in germination rate. PVC treatment alone had no significant effect on germination. MPs + Cu inhibited seed germination, which was mainly reflected in the deterioration of seed morphology. Cu significantly enhanced antioxidant enzyme activity, increased reactive oxygen species (ROS) and MDA content. The addition of low concentration PVC enhanced SOD activity, reduced MDA and H2O2 content. The SOD activity of the Cu2+8 + PVC10 group was 4.05 and 1.35 times higher than that of the control group and Cu treatment group at their peak, respectively. At this time, the CAT activity of the Cu2+8 + PVC5000 group increased by 2.66 and 1.42 times, and the H2O2 content was 2.02 times higher than the control. Most of the above indicators reached their peak at 24 h. The activity of α-amylase was inhibited by different treatments, but ß-amylase activity, starch and soluble sugar content did not change regularly. The research results can provide new ideas for evaluating the impact of MPs + Cu combined pollution on perilla and its potential ecological risk.

Effects of micro/nanoplastics on oxidative damage and serum biochemical parameters in rats and mice: a meta-analysis.

Micro/nanoplastics (MNPs) are emerging as environmental pollutants with potential threats to human health. The accumulation of MNPs in the body can cause oxidative stress and increase the risk of cardiovascular disease (CVD). With the aim to systematically evaluate the extent of MNPs-induced oxidative damage and serum biochemical parameters in rats and mice, a total of 36 eligible articles were included in this meta-analysis study. The results reported that MNPs can significantly increase the levels of oxidants such as reactive oxygen species (ROS) and malondialdehyde (MDA) (P < 0.05), and resulted in notable increase in serum biochemical parameters including aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (P < 0.05). Conversely, MNPs significantly reduced levels of antioxidants such as superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx) and catalase (CAT) (P < 0.05). Subgroup analysis revealed that smaller MNPs with oral administration and prolonged treatment, were associated with more pronounced oxidative stress and enhanced serum biochemical parameters alteration. In addition, after affected by MNPs, the levels of ALT and AST in liver group (SMD = 2.26, 95% CI = [1.59, 2.94] and SMD = 3.10, 95% CI = [1.25, 4.94]) were higher than those in other organs. These comprehensive results provide a scientific foundation for devising strategies to prevent MNPs-induced damage, contributing to solution of this environmental and health challenge.

Microplastics and microbiota: Unraveling the hidden environmental challenge.

This editorial explores the intricate relationship between microplastics (MPs) and gut microbiota, emphasizing the complexity and environmental health implications. The gut microbiota, a crucial component of gastrointestinal health, is examined in the context of potential microbial degradation of MPs. Furthermore, dysbiosis induced by MPs emerges as a consensus, disrupting the balance of gut microbiota and decreasing diversity. The mechanisms triggering dysbiosis, including physical interactions and chemical composition, are under investigation. Ongoing research addresses the consequences of MPs on immune fun-ction, nutrient metabolism, and overall host health. The bidirectional relationship between MPs and gut microbiota has significant implications for environmental and human health. Despite uncertainties, MPs negatively impact gut microbiota and health. Further research is essential to unravel the complex interactions and assess the long-term consequences of MPs on both environmental and human well-being.

Size Distributions of Microplastics in the St Louis Estuary and Western Lake Superior.

Identifying the sources and fate of microplastics in natural systems has garnered a great deal of attention because of their implications for ecosystem health. This work characterizes the size fraction, morphology, color, and polymer composition of microplastics in western Lake Superior and its adjacent harbor sampled in August and September 2021. The results reveal that the overall microplastic counts are similar, with the harbor stations ranging from 0.62 to 3.32 microplastics per liter and the lake stations ranged from 0.83 to 1.4 microplastics per liter. However, meaningful differences between the sample locations can be seen in the size fraction trends and polymer composition. Namely, the harbor samples had relatively larger amounts of the largest size fraction and more diversity of polymer types, which can be attributed to the urbanized activity and shorter water residence time. Power law size distribution modeling reveals deviations that help in the understanding of potential sources and removal mechanisms, although it significantly underpredicts microplastic counts for smaller-sized particles (5-45 µm), as determined by comparison with concurrently collected microplastic samples enumerated by Nile Red staining and flow cytometry.

Do Added Microplastics, Native Soil Properties, and Prevailing Climatic Conditions Have Consequences for Carbon and Nitrogen Contents in Soil? A Global Data Synthesis of Pot and Greenhouse Studies.

Microplastics threaten soil ecosystems, strongly influencing carbon (C) and nitrogen (N) contents. Interactions between microplastic properties and climatic and edaphic factors are poorly understood. We conducted a meta-analysis to assess the interactive effects of microplastic properties (type, shape, size, and content), native soil properties (texture, pH, and dissolved organic carbon (DOC)) and climatic factors (precipitation and temperature) on C and N contents in soil. We found that low-density polyethylene reduced total nitrogen (TN) content, whereas biodegradable polylactic acid led to a decrease in soil organic carbon (SOC). Microplastic fragments especially depleted TN, reducing aggregate stability, increasing N-mineralization and leaching, and consequently increasing the soil C/N ratio. Microplastic size affected outcomes; those <200 µm reduced both TN and SOC contents. Mineralization-induced nutrient losses were greatest at microplastic contents between 1 and 2.5% of soil weight. Sandy soils suffered the highest microplastic contamination-induced nutrient depletion. Alkaline soils showed the greatest SOC depletion, suggesting high SOC degradability. In low-DOC soils, microplastic contamination caused 2-fold greater TN depletion than in soils with high DOC. Sites with high precipitation and temperature had greatest decrease in TN and SOC contents. In conclusion, there are complex interactions determining microplastic impacts on soil health. Microplastic contamination always risks soil C and N depletion, but the severity depends on microplastic characteristics, native soil properties, and climatic conditions, with potential exacerbation by greenhouse emission-induced climate change.