Microplastics in aquatic environments: A review on occurrence, distribution, toxic effects, and implications for human health

Toxicity of long term exposure to low dose polystyrene microplastics and nanoplastics in human iPSC-derived cardiomyocytes

Microplastics and nanoplastics (MNPs) are widespread environmental pollutants with potential risks to human health including cardiovascular effects. However, the impact of MNPs on the heart, particularly in human-relevant cardiac models, remains poorly understood. In this study, we investigated the long term effects of polystyrene (PS) MNPs-1 μm (PS-1) and 0.05 μm (PS-0.05) in human iPSC-derived cardiomyocytes (hiPSC-CMs). PS MNPs exposure reduced myocyte viability in a time- and dose-dependent manner. At a low dose of 0.1 μg/L, both PS-0.05 and PS-1 suppressed myocyte contractility, reduced Ca2+ transient amplitude, and altered contraction and Ca2+ transient dynamics. In hypertrophic hiPSC-CMs, PS-0.05 exposure exacerbated hypertrophy, increasing cell size and proBNP expression, a marker of myocyte hypertrophy. The mechanism of PS MNPs-induced cardiotoxicity likely involved mitochondrial dysfunction, as indicated by decreased mitochondrial membrane potential, increased mitochondrial ROS, and elevated intracellular ROS levels. This is the first study to assess the long term impact of low dose MNPs in human cardiomyocytes, providing crucial insight into the potential cardiac toxicity of MNPs and their implications for human heart health.

Evaluating microplastic trapping efficiency in seagrass meadows using hydraulic flume simulations

Microplastic (MP) pollution poses a significant environmental threat, with projections indicating a 50-fold increase in pollution levels by 2100. Seagrass meadows, important for carbon storage and sediment stabilisation, may also serve as a Nature-based Solution for MP pollution. Despite the well-documented presence of MPs in seagrass sediments, the efficiencies of MP capture by these habitats remain largely unexplored. In this study, hydraulic flume simulations were conducted to assess how different seagrass planting configurations influence MP trapping. The results indicate that meadows with random spatial distribution are 6 % more effective at trapping MPs under high concentrations compared to grid-patterned meadows, while lower planting densities enhance trapping efficiency by 14 %. These findings offer insights into optimising seagrass restoration efforts for mitigating MP pollution, and this highlights the need for further needed to understand the broader ecological implications of MP retention in these critical ecosystems.

Mass spectrometry imaging enables detection of MPs and their effects in Daphnia magna following acute exposure

Microplastics (MPs) are continuously found in soil and water environments. Within aquatic ecosystems, filter-feeding organisms are unable to discriminate MPs from food particles while fish may intentionally ingest MPs by mistaking them for prey. In both cases, MPs can accumulate in tissues with subsequent implications for human and environmental health. The modes of action of MPs are still not fully understood and hence the toxicological effects of these pollutants cannot be fully evaluated. This study aims to improve our understanding of the modes of action and toxicological effects of MPs using a multimodal approach. In the present study, Daphnia magna was deployed as a model to investigate the acute effects of MPs by exposing D. magna specimens for 24 h to fluorophore-coated polyethylene MPs. A multimodal approach, combining fluorescence imaging and mass spectrometry imaging (MSI), was employed to assess the implications of MPs exposures. Fluorescent microscopy revealed a significant accumulation of MPs in the gut of D. magna after acute exposure. Secondary ion mass spectrometry (SIMS) and matrix-assisted laser desorption/ionization (MALDI) imaging were used to study the distribution and potential metabolic effects in exposed D. magna. ToF-SIMS revealed specific fragmentation patterns for polyethylene MPs, with the m/z 43 ion being the most suitable for identifying polyethylene MPs in biological tissue samples. MALDI-MSI showed specific ion types for the eye, gut, optical ganglion, first antennae, and egg tissues of D. magna. MSI data revealed minor alterations in specific regions of D. magna, such as eggs and gut, of D. magna after MPs exposure. The local changes were mainly found in the nucleotide and lipid metabolism within the eggs. In the gut, changes between control and MPs-exposed groups were potentially linked to plastic additives. Overall, the results of this work underline the potential of multimodal approaches based on MSI to study challenging pollutants, such as MPs, and their interactions with tissues.

Toxicological complexity of microplastics in terrestrial ecosystems

Microplastics (MPs), defined as plastic debris, smaller than <5 mm, are viewed as persistent contaminants that significantly modify terrestrial ecosystems and biodiversity by altering soil microbiota, structure, and functions. This paper summarizes MPs' interactions with various pollutants, including heavy metals and pesticides, also addressing socio-economic impacts, such as reduced agricultural yields and threats to regional fisheries. The study emphasizes the need for an on the basis of waste management model to mitigate these effects, advocating for collaborative efforts among stakeholders. Also, interdisciplinary studies incorporating material sciences, ecology, and environmental policy are essential to confront the challenges of MPs to ecological services. Additionally, the review highlights how MPs can serve as vectors for toxins to damage soil health and species survival. The overview underscores a complex interplay between environmental and socio-economic systems, addressing the urgency of harnessing MPs pollution and protecting ecosystem integrity and sustainability.

Emamectin Benzoate and Microplastics Led to Skeletal Muscle Atrophy in Common Carp via Induced Oxidative Stress, Mitochondrial Dysfunction, and Protein Synthesis and Degradation Imbalance

Pesticides and plastics have brought convenience to agricultural production and daily life, but they have also led to environmental pollution through residual chemicals. Emamectin benzoate (EMB) is among the most widely used insecticides, which can cause environmental pollution and harm the health of organisms. Additionally, microplastics (MPs), a relatively new type of pollutant, not only are increasing in residual amounts within water bodies and aquatic organisms but also exacerbate pollution by adsorbing other pollutants, leading to a mixed pollution scenario. Nevertheless, the toxicity and mechanism of EMB and MPs on common carp skeletal muscle have not been elucidated. Therefore, we established exposure models for EMB and MPs, and methods such as hematoxylin and eosin staining, immunofluorescence staining, JC-1 staining, and western blotting were employed to investigate the underlying mechanisms of skeletal muscle damage. The results of in vivo and in vitro experiments indicated that exposure to EMB or MPs led to oxidative stress, which in turn caused mitochondrial fusion/fission imbalance (with decreased Mfn1, Mfn2, and OPA1 and increased DRP1), reduced mitochondrial membrane potential, decreased ATP content, reduced protein synthesis, and increased degradation, ultimately resulting in skeletal muscle atrophy. Joint exposure caused more severe damage than single exposure, and the addition of NAC can effectively alleviate skeletal muscle atrophy. In summary, exposure to EMB and/or MPs induced excessive reactive oxygen species (ROS) production, giving rise to mitochondrial dysfunction and an imbalance in skeletal muscle protein synthesis and degradation, ultimately resulting in skeletal muscle atrophy in common carp.

Microplastic characterization and factors influencing its abundance in coastal wetlands: insights from the world's largest mangrove ecosystem, Sundarbans

Water and sediment samples were collected from 20 sampling sites within two major river systems within the world's largest mangrove ecosystem. The primary objectives of the study were to determine MPs' abundance, composition, and potential ecological risks and to identify the factors influencing their distribution and characteristics. Results revealed MP abundances, ranging from 2 to 53 items/m3 in water and 17 to 177 items/kg in sediment. The most prevalent types of MPs were films, fragments, foams, and fibers, with the most abundant fragments. Transparent MPs of various colors, such as red, green, blue, white, and yellow, were commonly observed. Additionally, sizes of MPs ranged from < 0.5 to 5 mm, with particles < 0.5 mm dominating in water and 4-5 mm particles prevailing in sediment. Six major polymers were identified, including polystyrene (PS), polyamide (PA), Polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), and ethylene propylene diene monomer (EPDM), with PS being the most abundant in both river systems. Linear mixed effect models showed that factors, such as distance from Mongla port and water velocity impacted MP abundance in water, while distance from Mongla port, total organic carbon (TOC), and total phosphorus (TP) contents affected their distribution in sediment. The Shannon-Weaver Index revealed a higher MP diversity in the Shela River compared to the Pasur. Overall, the pollution load index (PLI) and polymeric hazard index (PHI) indicated that MPs impacted both river systems, but the finding from the ecological risk index (ERI) was negligible at the individual sites. Our study recommends the long-term monitoring of MP abundance and implementation of strict regulations to reduce MPs in aquatic environments and proposes various engineering and biotechnological approaches for effective MP remediation. Further research is needed to identify both point and non-point sources of MPs and develop comprehensive strategies and policies to mitigate plastic pollution in the mangrove ecosystem.

Impact and mechanism of polyethylene terephthalate microplastics with different particle sizes on sludge anaerobic digestion

Municipal wastewater treatment plants (WWTPs) are important sinks for microplastics, and the vast majority of microplastics entering WWTPs are trapped in residual sludge. In order to investigate the effect of microplastics on anaerobic digestion of sludge, polyethylene terephthalate (PET) microplastics with common particle size and physical aging were selected to conduct a comparative study. Regardless of aging, the addition of 300 and 500 μm PET microplastics inhibited methane production, with their cumulative methane production reduced by 11.3-24.9% compared to the control group. In contrast, when 100 μm microplastics were added, the raw PET promoted methane production, yielding 337 L CH4/kg VS, while the aged experimental group showed similar yields to the control group. For the 800 μm microplastics treatment group, aged microplastics facilitated methane production while raw microplastics inhibited it, with methane production of 91.0% and 111% of the control group, respectively. The effects were also investigated by model fitting, stage discussion, and microbial community structure analysis. The results discovered that the main rate-limiting steps of adding microplastics with smaller or larger particle sizes (100, 800 μm) to methane production were solubilization and hydrolysis, while the main rate-limiting step of microplastics with medium particle sizes (300, 500 μm) was methanogenesis. Physically aged PET microplastics with smaller or larger sizes showed a more significant effect on methane production. Furthermore, PET microplastics altered the microbial community structure, shifting methanogens from acetotrophic pathways to hydrotrophic pathways. This study offers new insights into the performance analysis of sludge anaerobic digestion in practical WWTPs.

How does the tidal cycle influence the estuarine dynamics of microplastics?

Estuaries are the main pathway for the microplastics (MPs) to enter into the oceans. However, factors that drive river-sea transport of MPs are not yet fully understood. Therefore, our research investigated the influence of the tidal cycle on the abundance and characteristics of MPs in an urban estuary, through high-frequency sampling (every 2-3 h) using a plankton net (120 μm mesh size) in two seasons (rainy and dry seasons). The results showed that the abundance of MPs decreased during the ebb tide and increased during the flood tide. A positive correlation was found between MP abundance and water height in both seasons. The shapes and colors of MPs varied significantly throughout the tidal cycle. The results show that tides are key agents in the transfer of MPs and cannot be neglected in models of the global contribution of plastic pollution from rivers to oceans.

Identification and Characterization of New Hafnia Strains from Common Carp (Cyprinus carpio), Potentially Possessing Probiotic Properties and Plastic Biodegradation Capabilities

Finding and characterizing new bacterial strains, including probiotic strains, is a crucial task in today's world to expand the genetic data pool and identify new genes. In this study, we investigated the gut microbiota of one industrial species, Cyprinus carpio, and identified representatives of various microbial genera, including Citrobacter, Serratia, Bacillus, Enterococcus, and Kocuria. Notably, we discovered two strains of Hafnia with potentially probiotic properties. We conducted next-generation sequencing (NGS) of these strains, described their antibiotic resistance and antibacterial activity, and compared them with other representatives of the Hafnia genus. These strains, characterized by rapid growth, the presence of the ClpB heat shock protein gene, and genes associated with microplastic degradation, provide a promising basis for further research, including studies on their potential application in plastic biodegradation.

Osmoregulation affects elimination of microplastics in fish in freshwater and marine environments

In recent decades, microplastics (MPs) have emerged as one of the biggest environmental challenges in aquatic environments. Ingestion and toxicity of MPs in seawater (SW) and freshwater (FW) fish have been studied extensively both in field and laboratory settings. However, the basic mechanism of how fish deal with MPs in SW and FW remains unclear, although physiological conditions of fish differ significantly in the two environments. In this study, using Javanese medaka (Oryzias javanicus), a euryhaline fish that adapts readily to both SW and FW, we investigated elimination of MPs in fish in SW and FW environments. We exposed O. javanicus larvae (21 days post-hatching) to 0.25 mg/L of fluorescent polystyrene microspheres (1 μm) for 24 hours and then conducted an elimination test for up to 5 days. Results showed that the gut retention time of MPs is longer in FW than in SW, indicating that MP elimination occurs more quickly in SW than in FW. However, higher numbers of MPs tended to be retained longer in SW larvae than FW larvae. Subsequently, using a fluorescent marker, gastrointestinal fluid was found to move more rapidly in the SW group. This finding indicates that water drinking accelerates gastrointestinal fluid movement, which moves MPs through the gut in SW larvae. Beside the difference in physiological conditions, MP elimination was faster when food was available, suggesting that feeding also affects MP elimination in fish. Internal factors such as body size and intestine length were also examined, but indicated no significant difference. Therefore, osmoregulation and feeding both influence MP elimination in fish.

Exploring Innovative Approaches for the Analysis of Micro- and Nanoplastics: Breakthroughs in (Bio)Sensing Techniques

Plastic pollution, particularly from microplastics (MPs) and nanoplastics (NPs), has become a critical environmental and health concern due to their widespread distribution, persistence, and potential toxicity. MPs and NPs originate from primary sources, such as cosmetic microspheres or synthetic fibers, and secondary fragmentation of larger plastics through environmental degradation. These particles, typically less than 5 mm, are found globally, from deep seabeds to human tissues, and are known to adsorb and release harmful pollutants, exacerbating ecological and health risks. Effective detection and quantification of MPs and NPs are essential for understanding and mitigating their impacts. Current analytical methods include physical and chemical techniques. Physical methods, such as optical and electron microscopy, provide morphological details but often lack specificity and are time-intensive. Chemical analyses, such as Fourier transform infrared (FTIR) and Raman spectroscopy, offer molecular specificity but face challenges with smaller particle sizes and complex matrices. Thermal analytical methods, including pyrolysis gas chromatography-mass spectrometry (Py-GC-MS), provide compositional insights but are destructive and limited in morphological analysis. Emerging (bio)sensing technologies show promise in addressing these challenges. Electrochemical biosensors offer cost-effective, portable, and sensitive platforms, leveraging principles such as voltammetry and impedance to detect MPs and their adsorbed pollutants. Plasmonic techniques, including surface plasmon resonance (SPR) and surface-enhanced Raman spectroscopy (SERS), provide high sensitivity and specificity through nanostructure-enhanced detection. Fluorescent biosensors utilizing microbial or enzymatic elements enable the real-time monitoring of plastic degradation products, such as terephthalic acid from polyethylene terephthalate (PET). Advancements in these innovative approaches pave the way for more accurate, scalable, and environmentally compatible detection solutions, contributing to improved monitoring and remediation strategies. This review highlights the potential of biosensors as advanced analytical methods, including a section on prospects that address the challenges that could lead to significant advancements in environmental monitoring, highlighting the necessity of testing the new sensing developments under real conditions (composition/matrix of the samples), which are often overlooked, as well as the study of peptides as a novel recognition element in microplastic sensing.

Cellular pathway disturbances elicited by realistic dexamethasone concentrations in gills of mussel Mytilus galloprovincialis as assessed by a multi-biomarker approach

The growing usage of glucocorticoids for a variety of diseases raises concerns since these drugs, including the anti-inflammatory dexamethasone (DEX), are frequently found in the environment. The impact of DEX was evaluated on mussels Mytilus galloprovincialis (Lamarck, 1819) by exposure to environmental concentrations (C1: 4 ng/L; C2: 40 ng/L; C3: 400 ng/L; C4: 2000 ng/L), and sampling at 3 (T3), 6 (T6), and 12 (T12) days. A multi-biomarker approach was applied on gills, involved in gas exchange, feed filtering, and osmoregulation. A dose- and time-dependent uptake of DEX was recorded, besides haemocyte infiltration, increased neutral and acid mucopolysaccharides, and a general pro-oxidant effect witnessed by lipid peroxidation and altered antioxidant system. Metabolomics revealed rise in protein turnover and energy demand by fluctuations in free amino acids (alanine, glycine) and energy-related metabolites (succinate, ATP/ADP). It is necessary to reduce DEX dosage from the environment by recovery strategies and effective eco-pharmacovigilance programs.

Aging process potentially aggravates microplastic toxicity in aquatic organisms: Evidence from a comprehensive synthesis

Microplastics (MPs; <5 mm) will inevitably encounter aging processes after being released into the environment. However, the effect of aging on MPs toxicity in aquatic environment is still unclear despite that aging plays a critical role in changing MPs characteristics and behavior. Here, we conducted a meta-analysis to assess the effects of aging on MPs biotoxicity in aquatic environment. We found that aging displayed an overall aggravating effect (Hedges' g = -0.595, P < 0.05) on MPs toxicity in aquatic organisms, while the effects varied across different taxa; namely, aging potentially alleviates MPs biotoxicity to hydrophytes (Hedges' g = 0.383, P > 0.05) while significantly exacerbates MPs toxicity to other organisms, such as algae (Hedges' g = -0.784, P < 0.05), zooplanktons (Hedges' g = -0.366, P < 0.05), and fish (Hedges' g = -0.560, P < 0.05). Moreover, the aggravating effects of aging on MPs biotoxicity were closely related to biological traits (e.g., Hedges' g = -0.378 for growth and development, Hedges' g = -0.957 for metabolism, and Hedges' g = 0.054 for immune system). We further found that aging methods, MPs characteristics, and environmental designs were also crucial regulators for the aging impacts on MPs toxicity. Taken together, our findings demonstrated that aging process appears to boost MPs biotoxicity, and there are complex factors determining aging impacts on MPs biotoxicity. Given the persistent release of MPs and the aggravating effects of aging in aquatic environments, the risk posed by MPs should be carefully considered in the future.

Accumulation kinetics of polystyrene nano- and microplastics in the waterflea Daphnia magna and trophic transfer to the mysid Limnomysis benedeni

Despite the pervasive presence of nano- and microplastics (NMPs) in aquatic environments, their movement through food chains remains poorly understood. In this study, we explored the uptake of polystyrene plastics (PSPs) of varying sizes (26, 500, and 4800 nm) in Daphnia magna and their subsequent transfer to the freshwater mysid Limnomysis benedeni, shedding light on the intricate dynamics of NMP transfer in freshwater ecosystems. Our results show that in D. magna the internal concentration of 4800 nm PSPs was 4-10 times higher than that of 26 and 500 nm PSPs, respectively. The uptake rate constants in daphnids decreased in the following order: 4800 nm (2.4 ± 0.5 L/g·h) > 26 nm (1.7 ± 0.4 L/g·h) > 500 nm (0.6 ± 0.1 L/g·h) PSPs. Importantly, only a small fraction (1-5 %) of the PSPs ingested by D. magna was transferred to L. benedeni. Additionally, larger particle sizes were associated with a higher extent of transfer in the food chain. Elimination rate constants in L. benedeni were found to be 0.03 ± 0.03, 0.1 ± 0.2, and 0.2 ± 0.8 per hour for 26, 500, and 4800 nm PSPs, respectively. Fluorescence observations revealed that PSPs were predominantly located in the stomach and intestine of L. benedeni. Furthermore, the calculated trophic transfer factor, based on the mass of particles accumulated in the organisms, was <1 for all PSP treatments. Our results indicate that NMPs can be transferred along the daphnia-mysids food chain, and that there is no evidence of biomagnification along this chain. These findings underscore the importance of understanding particle size effects on NMP transfer and accumulation in aquatic food webs, offering valuable insights for assessing the ecological risks associated with NMP pollution in freshwater ecosystems.

Microplastic pollution along the coastal island shorelines of Bangladesh: Distribution, patterns, and abundance

Microplastics (MPs), less than 5 mm in length, have become a major environmental issue due to their hazardous physical and chemical properties. The research investigated 54 sediment samples collected from three different zones of the beaches, namely the wrack line, beach face, and swash zone. This study aims to enumerate the number and polymeric variety of microplastics found in beach sediments from coastal islands of Bangladesh, including Sandwip, Kutubdia, and Saint Martin's Island in the northeastern Bay of Bengal. NaCl solution with the density of 1.2 g/cm3 was used as a density-separating solvent. Microplastics were extracted using conventional protocols, yielding an average of 193 ± 68.9, 175.5 ± 63.1, and 266.3 ± 232 particles per kg from the collected samples of Sandwip, Kutubdia, and Saint Martin's Island respectively, with five morphotypes: fiber, film, fragment, foam, and pellet, where fiber dominated each island. White microplastics were most spread in both Sandwip and Saint Martin's Island, whereas translucent and blue were most abundant in Kutubdia. Moreover, polypropylene (PP) was shown to be the greatest number of polymer groups among those analyzed microplastic particles using ATR-FTIR (Attenuated total reflectance-Fourier transform infrared) spectrometer. Using scanning electron microscopy (SEM), it was also possible to detect surface degradation, rupture, or fracture that was probably caused by the environment. The study emphasizes the critical need for continued research and monitoring to better understand the dynamics of microplastic pollution and its long-term impacts. By tackling the underlying causes and implementing effective management practices, we can achieve a cleaner and more sustainable future for coastal communities and marine ecosystems.

Association between blood microplastic levels and severity of extracranial artery stenosis

Microplastics (MPs) contamination raises concerns about their impact on human health, particularly cardiovascular diseases. This study investigated the blood MPs levels in patients with extracranial artery stenosis (ECAS) and their possible link to disease severity. 20 ECAS and 10 control patients were recruited. Blood samples, collected before the digital subtract angiography (DSA) procedure, were analyzed by pyrolysis-gas chromatography mass spectrometry (Py-GC/MS), laser direct infrared (LDIR) spectroscopy, and scanning electron microscopy (SEM). Demographic and clinical information was also examined. Strict quality controls were implemented to prevent contamination. MPs were detected by Py-GC/MS in all blood samples, with concentrations significantly higher in ECAS group compared to control (174.89 ± 24.95 vs 79.82 ± 31.73 μg/g, p < 0.001), and polyvinyl chloride (PVC) and polyamide 66 (PA66) were the most abundant among the detected polymers. Further analyses suggested that higher concentrations of MPs may be associated with more severe artery stenosis (p < 0.001). Compared with the normal group, ECAS group had a higher level of D-dimer (0.61 ± 0.6 μg/L vs 0.28 ± 0.09 μg/L, p < 0.05) and longer Thrombin Time (sec) (18.30 ± 3.43 μg/L vs 16.25 ± 1.74 μg/L, p < 0.05). Additionally, LDIR and SEM detected the shape and physical properties of the MPs. In this study, we revealed significant higher blood MPs levels in ECAS patients, with a notable correlation between MPs concentrations and arterial stenosis severity.

Characterization and ecological risks of microplastics in urban road runoff

Microplastics (MPs) deposited on urban roads are often flushed into water bodies via drainage systems without treatment, and MP concentrations in the initial road runoff may be particularly high. Yet, there is only a limited understanding of the characteristics, dynamics, and impacts of MPs in urban road runoff. In this study, stormwater and rainwater samples were collected from seven different locations in Hong Kong across 11 rainfall events between February 2021 and September 2022. Characteristics of MPs in the collected samples were analyzed in detail, along with the dynamics of MP concentration in rainfall events, possible influencing factors, and ecological risks. The results show that MP concentration in the initial road runoff is particularly high during a rainfall episode. Overall, the median MP abundance in the collected runoff samples (185 particles/L) was 4.6 times higher than that in rainwater (40 particles/L). The most common polymers identified were polyethylene, polypropylene, and polystyrene, with fragments being the dominant shape. Over 60 % of MP sizes were smaller than 300 μm in the runoff samples. Additionally, risk assessments based on the Polymer Risk Index (PRI) classified most road sites in pollution classes II to III (PRI = 13.3-138.0), indicating moderate to high ecological risks. It appears that MP abundance in the initial runoff was significantly influenced by seasonal changes. These findings highlight urban roads as a major source of MP pollution in stormwater runoff and emphasize the importance of addressing the initial runoff in pollution control.

Effects of microplastics separate exposure and co-exposure to 17β-estradiol on the productive performance of juvenile female Chinese mitten crab (Eriocheir sinensis)

Microplastics (MPs) and endocrine-disrupting chemicals are persistent and ubiquitous pollutants in aquatic environments. The coexistence of MPs and 17β-estradiol (E2) in aquaculture water is concerning, yet their combined impact on aquaculture products remains unclear. In this study, we investigated the individual and combined effects of MPs and E2 on juvenile female Chinese mitten crabs (Eriocheir sinensis). The results revealed that MPs and E2, alone and in combination, damage the histology and ultrastructure of the hepatopancreas, reduce lipid storage, and inhibit the expression of genes related to innate immunity, energy metabolism, and reproductive development in the hepatopancreas. These effects result in decreased innate immunity and impact growth and development. MPs and E2 also damage pereiopod muscles and ovarian tissues, impairing locomotor function and reproductive development. The coexposure group exhibited the combined damage effects of MPs and E2. Fluctuations in gene expression at different time points suggest that E. sinensis is self-regulated in response to external stimuli from MPs and E2. These findings emphasize the effects of MPs and E2, indicating that their coexistence in aquaculture environments threatens the productive performance of E. sinensis.

Bioaccumulation and biochemical impact of polyethylene terephthalate microplastics in Cipangopaludina chinensis: Tissue-specific analysis and homeostasis disruption

Microplastics are a novel pollutant that adversely affect freshwater benthic organisms. However, few studies have investigated the mechanism underlying the bioaccumulation and the toxicity of microplastics. In this study, microplastics bioaccumulation of wild Cipangopaludina chinensis in the Songhua River were utilized, and a 28-day aquatic toxicity test was performed to determine the effects of exposure to polyethylene terephthalate (PET), the bioaccumulation of PET, and changes in multiple biomarkers in the muscle, gill, and kidney tissues. The concentration pattern of microplastics was as follows: kidney tissue > muscle tissue > gill tissue. Microplastic ingestion caused AChE inhibition led to significant increases in redox and energy metabolism indicators. Furthermore, the IBR analysis presented a "response-resistance-breakdown" process, indicating that Cipangopaludina chinensis possessed resistance with time (D14 and D21) and concentration (0.10 mg/L and 1.00 mg/L) thresholds. Tissue sensitivity to microplastics was ranked as gill > muscle > kidney, which was the opposite order of microplastic accumulation. These findings implied that less sensitive tissues stored a larger amount of pollutants, suggesting a reduction in tissue sensitivity to microplastics with higher microplastic occurrence rates. This study provides new insights into biological resistance to pollutant stress, warranting further investigation into the underlying mechanisms.

Microfibre pollution: An emerging contaminant, alarming threat to the global environment

Microfibres, mostly obtained from home laundry, textiles, industrial materials, sewage effluents, and sludge, are considered the main source of environmental pollution, which has become a prevalent threat to terrestrial and aquatic creatures. Global population growth and industrialization have led to a rise in fibre consumption and production, which spread its network in drinking water, beer, and seafood. Focusing on the alarming threat of microfibre towards the natural environment, we have penned an extensive review article about microfibre pollution. The manuscript is divided into various subparts, such as the introductory portion, which briefly summarizes the sources and presence of various hazardous pollutants in the environment, followed by a detailed discussion about microfibre. The second part elaborates on the sources and distribution of microfibreous pollutants and the third portion discloses the toxic chemicals utilized or produced from functionalization, as well as the negative implications of microfibre on the environment. The fourth part discloses the leading application strategies to diminish microfibre pollution by controlling the sources and the development of various remediations. The last portion deals with the future and critical aspects of microfibre contamination. The authors hope this review article will boost its domain in environmental chemistry, sustainable development and environmental engineering from academic to industrial level as it helps researchers in particular and academics in general.

Microplastic dynamics and risk projections in West African coastal areas: Developing a vulnerability index, adverse ecological pathways, and mitigation framework using remote-sensed oceanographic profiles

Microplastic pollution presents a serious risk to marine ecosystems worldwide, with West Africa being especially susceptible. This study sought to identify the key factors driving microplastic dynamics in the region. Using NASA's Giovanni system, we analyzed environmental data from 2019 to 2024. Results showed uniform offshore air temperatures due to turbulence (25.22-45.62 K) with significant variations nearshore. Salinity levels remained largely stable (4 PSU) but slightly decreased in southern Nigeria. Surface wind speeds rose from 4.206-5.026 m/s in Nigeria to over 5.848 m/s off Mauritania, while eastward stress hotspots were prominent in Nigeria and from Sierra Leone to Senegal. Photosynthetically available radiation (PAR) beam values peaked off Mauritania and dipped from Nigeria to Sierra Leone, with the inverse pattern observed for diffuse PAR. Hotspots of high absorption, particulate backscattering, elevated aerosol optical depth, and remote sensing reflectance all pointed to substantial particulate matter concentrations. The Microplastic Vulnerability Index (MVI) identifies the coastal stretch from Nigeria to Guinea-Bissau as highly vulnerable to microplastic accumulation due to conditions that favor buildup. In contrast, moderate vulnerability was observed from Guinea-Bissau to Senegal and in Mauritania, where conditions were less extreme, such as higher offshore temperatures that could promote widespread microplastic suspension and cooler nearshore temperatures that favor sedimentation. Increased turbulence and temperatures in coastal areas of Senegal and Mauritania may enhance microplastic transport and impact marine life. In Nigeria, stable coastal conditions-characterized by consistent temperatures, low turbulence, and uniform salinity-may lead to increased persistence and accumulation of microplastics in sensitive habitats like mangroves and coral reefs. These findings highlight the need for region-specific management strategies to address microplastic pollution and effectively protect marine ecosystems.

Potential ecological risk assessment of microplastics in environmental compartments in Mexico: A meta-analysis

Microplastic (MP) environmental contamination has been widely studied in Mexico. However, the evaluation of the associated risk to MPs in environmental compartments is scarce. Therefore, this study addresses this issue using diverse indicators such as the Pollution Load Index (PLI), the Polymer Risk Index (PRI), and the Potential Ecological Risk Index (PERI). The results of a meta-analysis revealed high MP contamination levels in most of the studied compartments, which included marine and estuarine waters, beach sand, freshwater, sediments, and biota. Regarding the risk assessment indicators, PLIs indicated low (56%), dangerous (22%), moderate (12%), and high (10%) levels across compartments. Meanwhile, PRIs displayed concerning values, with 36%, 35%, 20%, and 9% exhibiting dangerous, high, moderate, and low levels, respectively. Thus, high PRI values emphasized the significant rise in MP pollution, largely attributed to high-hazard polymer compositions. Otherwise, PERIs showed low (56%), very dangerous (29%), moderate (6%), high (5%), and dangerous (4%) levels. Thus, the ecological risk in Mexico is widespread and mainly linked to MP abundance, polymer type, environmental matrix, and characteristics of organisms. This study represents the first attempt at MP ecological risk assessment in Mexico, providing crucial insights for developing mitigation strategies to address concerns about MP contamination.

Impacts of polyhydroxybutyrate (PHB) microplastic exposure on physiology and metabolic profiles of Litopenaeus vannamei

In light of increasing concerns about microplastic pollution, it is crucial to understand the biological impacts of biodegradable PHB microplastics on marine organisms. This study included a 96-h exposure experiment to assess acute toxicity at PHB concentrations of 0 mg/L, 100 mg/L, 500 mg/L and 1000 mg/L. Additionally, a 60-day feeding trial was conducted with PHB concentrations of 0, 0.5, 1.0 and 2.0 g/kg to evaluate the long-term effects on growth, physiological health and metabolic responses of Litopenaeus vannamei. Results from the exposure experiment indicated that PHB microplastics up to 100 mg/L were non-toxic to shrimp. However, the 60-day feeding trial revealed that higher concentrations led to slight reductions in survival rates and growth performance, indicating a concentration-dependent response. Analysis of antioxidant and immune enzymes showed minimal changes across most parameters. However, increases in malondialdehyde content and lysozyme activity at higher PHB levels suggested a stress response. Microbial analysis indicated higher species richness and greater community diversity in the PHB group compared to controls, as evidenced by Chao1, ACE, Shannon and Simpson indices. Linear discriminant analysis revealed that Enterobacteriales and related taxa were more prevalent in the PHB group, while Rhodobacteraceae and associated taxa dominated the control group. Pathway analysis highlighted enhanced signal transduction, cell mobility and metabolic resource reallocation in response to PHB-induced stress. Integrated transcriptomic and metabolomic analyses revealed significant regulatory changes, especially in lipid metabolism pathways. These findings suggest that while PHB microplastics trigger adaptive metabolic responses in shrimp, they do not cause acute toxicity. Significant variations in intestinal microbiome composition reflect potential shifts in gut health dynamics due to PHB ingestion. This study enhances our understanding of the ecological impacts of microplastics and underscores the necessity for further research into the environmental safety of biodegradable alternatives.

The use of chitosan as an antioxidant in the feed of cultivated P. vannamei shrimp against oxidative stress induced by exposure to microplastics

Microplastics (MP) are omnipresent in aquaculture and can induce several toxic effects, mainly oxidative stress. Therefore, alternatives to minimize these effects are welcome. In this study, chitosan (1 and 3 g/kg) was supplemented through the feed of farmed shrimp P. vannamei for 30 days. After this period, the shrimp were exposed to MP (0.5 mg/L) for 7 days. The results showed the presence of MP in hepatopancreas, gills and muscle. Hepatopancreas morphological alterations, as well as lipid peroxidation, a decrease in GSH level, and an increase in SOD activity indicated an oxidative stress that was reversed by chitosan. The muscle was also affected by MP, showing decreased CAT activity and increased SOD activity, though no lipid peroxidation was observed. In muscle, chitosan reversed the SOD increase to basal activity. The results obtained showed that chitosan was more effective against oxidative stress than in preventing accumulation and histological damage.

Micro(nano)plastic and Related Chemicals: Emerging Contaminants in Environment, Food and Health Impacts

Microplastic pollution is a problem of increasing concern in food, and while food safety issues around the world are serious, an increasing number of food safety issues related to microplastics have become the focus of people's attention. The presence of microplastics in food is a worldwide problem, and they are present in all kinds of foods, foods of both animal and plant origin, food additives, drinks, plastic food packaging, and agricultural practices. This can cause problems for both humans and the environment. Microplastics have already been detected in human blood, heart, placenta, and breastmilk, but their effects in humans are not well understood. Studies with mammals and human cells or organoids have given perspective about the potential impact of micro(nano)plastics on human health, which affect the lungs, kidneys, heart, neurological system, and DNA. Additionally, as plastics often contain additives or other substances, the potentially harmful effects of exposure to these substances must also be carefully studied before any conclusions can be drawn. The study of microplastics is very complex as there are many factors to account for, such as differences in particle sizes, constituents, shapes, additives, contaminants, concentrations, etc. This review summarizes the more recent research on the presence of microplastic and other plastic-related chemical pollutants in food and their potential impacts on human health.

Biofilms in plastisphere from freshwater wetlands: Biofilm formation, bacterial community assembly, and biogeochemical cycles

Microorganisms can colonize to the surface of microplastics (MPs) to form biofilms, termed "plastisphere", which could significantly change their physiochemical properties and ecological roles. However, the biofilm characteristics and the deep mechanisms (interaction, assembly, and biogeochemical cycles) underlying plastisphere in wetlands currently lack a comprehensive perspective. In this study, in situ biofilm formation experiments were performed in a park with different types of wetlands to examine the plastisphere by extrinsic addition of PVC MPs in summer and winter, respectively. Results from the spectroscopic and microscopic analyses revealed that biofilms attached to the MPs in constructed forest wetlands contained the most abundant biomass and extracellular polymeric substances. Meanwhile, data from the high-throughput sequencing showed lower diversity in plastisphere compared with soil bacterial communities. Network analysis suggested a simple and unstable co-occurrence pattern in plastisphere, and the null model indicated increased deterministic process of heterogeneous selection for its community assembly. Based on the quantification of biogeochemical cycling genes by high-throughput qPCR, the relative abundances of genes involving in carbon degradation, carbon fixation, and denitrification were significantly higher in plastisphere than those of soil communities. This study greatly enhanced our understanding of biofilm formation and ecological effects of MPs in freshwater wetlands.

Microplastics in Indonesian land and aquatic environment: From research activities to regulation policies

Indonesia is suspected as one of the largest plastic waste contributors to the ocean, resulting in microplastic (MP) contamination of the marine environment. Likewise, >250 MP research in Indonesia have been published in the last decade, including review articles. However, a comprehensive review covering MP observations in all areas, i.e. land, freshwater, and ocean, and the regulation aspect in Indonesia remains unexplored. This review finds that the current MP studies are not sufficient to provide the big picture of MP distribution in Indonesia, suggesting the need for research guidelines and coordination among scholars in this field. In addition, the currently implemented local regulation in plastic item limitation should be supported by effective monitoring, sanction, and education for citizens, as well as investment in waste management facilities. Overall, this review suggests the improvement of MP studies and national regulation as countermeasures for MP pollution problems.

Fiddler crabs (Tubuca arcuata) as bioindicators of microplastic pollution in mangrove sediments

In recent years, microplastics (MPs) have been widely found in the environment and pose potential risks to ecosystems, which attracted people's attention. Using bioindicators has been a great approach to understanding the pollution levels, bioavailability, and ecological risks of pollutants. However, only few studies have investigated MPs in mangrove ecosystems, with few bioindicators of MPs. Herein, the distribution of MPs in mangrove sediments and fiddler crabs (Tubuca arcuata) in mangroves was investigated. Results showed that the abundance values of MPs are 1160‒12,120 items/kg and 11-100 items/ind. in mangrove sediments and fiddler crabs, respectively. The dominant shape of MPs detected in mangrove sediments and fiddler crabs was fragments with sizes of 20‒1000 μm, larger MPs of 50-1000 μm were found in abundance. Polypropylene (PP), which is one of the most commonly used plastic materials, was the main polymer type. The distribution of MPs in fiddler crabs closely resembled that in surface mangrove sediments with a strong linear correlation (R2 > 0.8 and p < 0.05) between their abundance. Therefore, the MP contamination level in mangrove sediments can be determined by studying MP pollution in fiddler crabs. Moreover, the results of the target group index (TGI) indicated that fiddler crabs prefer feeding specific MPs in mangrove sediments. Our findings demonstrate the suitability of fiddler crabs as bioindicators for assessing MP pollution in mangrove sediments.

Evaluation of antibiofilm activity of metal oxides nanoparticles and carbon nanotubes coated styrofoam on the bacterium Jeotgalicoccus huakuii

The co-existence of metal oxide nanoparticles (MONPs), carbon-based nanomaterials and microplastics (MPs) in the natural environment are expected to be of growing global concern due to their increasing abundance and persistence in the environment worldwide. Knowledge of the interaction of the above compounds particularly under light irradiation in water remains limited. In the present study, the possible individual and combined toxic effects of MONPs, carbon nanotubes (CNTs) through styrofoam (SF) on the environmental bacterium Jeotaglicoccus huakuii were systematically investigated. The fabricated MONPs and CNTs were characterized using the following techniques: FT-IR (functional groups), XRD (crystallinity), SEM, and EDX (topological morphology). The objective of this study was to investigate and identify naturally occurring bacteria capable of mitigating and detoxifying toxic pollutants under adverse conditions. Moreover, the assessment of minimum inhibitory concentration (MIC) was made through an agar well plate method, resazurin (ELISA measurement), growth kinetics and bacterial viability were assessed employing live and dead assay and biofilm combating ability was analyzed using an antibiofilm assay. Further, the biotransformation of f-MWCNTs by J. huakuii was evaluated employing RT-PCR and SEM analysis. The results demonstrated that the toxicity of Pb3O4@f-MWCNTs was comparatively higher than the remaining Pb3O4 NPs and SF coated NPs.. Interestingly, J. huakuii showed resistance against f-MWCNTs at very high concentrations and able to utilize f-MWCNTs as a sole carbon source suggesting J. huakuii as a suitable aquatic bioremediation tool for both MONPs and CNTs transfer via MPs. The results also enhanced our understanding of the affinity of MPs towards MONPs and CNTs under extreme environmental conditions.

Genotoxicity and metabolic changes induced via ingestion of virgin and UV-aged polyethylene microplastics by the freshwater fish Perca fluviatilis

The present study aims to compare and assess the toxicity induced by aged (irradiated with ultraviolet radiation for 120 days) polyethylene microplastics (PE-MPs) in comparison to virgin (non-irradiated) ones, after feeding the freshwater fish Perca fluviatilis. To this end, MPs mediated genotoxicity was assessed by the investigation of micronucleus nuclear abnormalities frequency in fish blood, and the degree of DNA damage in the liver and muscle tissues, while metabolic alterations were also recorded in both tissues. Results showed that both virgin and aged PE-MPs induced signaling pathways leading to DNA damage and nuclear abnormalities, as well as metabolites changes in all tissues studied. Metabolic changes revealed that the metabolism of nucleic acids, energy, amino acids, and neurotransmitters was more disrupted in the liver and by aged PE-MPs compared to muscles. Fish fed with aged PE-MPs exhibited greater DNA damage, while blood cells of fish fed with virgin PE-MPs seemed to be more vulnerable to nuclear abnormalities in relation to those fed with aged PE-MPs. Moreover, aged PE-MPs induced more acute overall effects on the metabolic profiles of fish tissues, and initiated stronger stress responses, inflammation, and cellular damages in fish tissues in relation to virgin ones. Characterization of both virgin and aged MPs revealed that the latter exhibited lower crystallinity and melting point, more irregular shapes and higher moiety of oxygen and carbonyl groups, which could be attributed for their observed higher toxicity. The research outcomes provide significant insights for advancing toxicological investigations in this field.

Airborne transboundary microplastics-A Swirl around the globe

Microplastics are persistent pollutants discovered and extensively researched in marine, freshwater, and terrestrial ecosystems but have yet to receive attention in an atmospheric context. Although recent reports stated the presence of microplastics in the air, their global existence and distribution are not critically discussed to date. This review aimed to investigate the current status of research on atmospheric microplastics through bibliometric analysis and by comparing and summarising published research on global distribution. The review also provides a summary of methods that have been used to collect samples, identify microplastics, quantify their occurrence, and determine their transport mechanisms. The bibliometric analysis revealed that atmospheric microplastic studies predominantly originated in China. Clothing, vehicle, and tire materials were the major primary sources while house furniture, construction materials, landfills, urban dust, plastic recycling processes, and agricultural sludge were precursor secondary sources. Polyethylene, polypropylene, and polyethylene terephthalate microfibres have most frequently found in indoor and outdoor atmospheres. Level of urbanization and temporal or spatial distributions governs the fate of airborne microplastics, however, the knowledge gap in the retention and circulation of microplastics through the atmosphere is still large. Many challenges and limitations were identified in the methods used, presentation of data, aerodynamic processes facilitating atmospheric transport, and scarcity of research in spatially and temporally diverse contexts. The review concluded that there was a greater need for globalization of research, methods and data standardization, and emphasizes the potential for future research with atmospheric transportation modelling and thermochemical analysis.

Ecotoxicological evaluation of chitosan biopolymer films particles in adult zebrafish (Danio rerio): A comparative study with polystyrene microplastics

To mitigate the environmental impact of microplastics (MPs), the scientific community has innovated sustainable and biodegradable polymers as viable alternatives to traditional plastics. Chitosan, the deacetylated form of chitin, stands as one of the most thoroughly investigated biopolymers and has garnered significant interest due to its versatile applications in both medical and cosmetic fields. Nevertheless, there is still a knowledge gap regarding the impact that chitosan biopolymer films (CBPF) may generate in aquatic organisms. In light of the foregoing, this study aimed to assess and compare the potential effects of CBPF on the gastrointestinal tract, gills, brain, and liver of Danio rerio against those induced by MPs. The findings revealed that both CBPF and MPs induced changes in the levels of oxidative stress biomarkers across all organs. However, it is essential to note that our star plots illustrate a tendency for CBPF to activate antioxidant enzymes and for MPs to produce oxidative damage. Regarding gene expression, our findings indicate that MPs led to an up-regulation in the expression of genes associated with apoptotic response (p53, casp3, cas9, bax, and bcl2) in all fish organs. Meanwhile, CBPF produced the same effect in genes related to antioxidant response (nrf1 and nrf2). Overall, our histological observations substantiated these effects, revealing the presence of plastic particles and tissue alterations in the gills and gastrointestinal tract of fish subjected to MPs. From these results, it can be concluded that CBPF does not represent a risk to fish after long exposure.

Photoaged polystyrene microplastics result in neurotoxicity associated with neurotransmission and neurodevelopment in zebrafish larvae (Danio rerio)

Microplastics (MPs) are emerging pollutants widely distributed in the environment, inducing toxic effects in various organisms. However, the neurotoxicity and underlying mechanisms of simulated sunlight-aged MPs have rarely been investigated. In this study, zebrafish (Danio rerio) were exposed to environmentally relevant concentrations (0, 0.1, 1, 10, and 100 μg/L) of virgin polystyrene (V-PS) and aged polystyrene (A-PS) for 120 hpf to evaluate the neurotoxicity. The results demonstrated that simulated sunlight irradiation altered the physicochemical properties (morphology, functional groups, and chemical composition) of V-PS. Exposure to A-PS causes greater toxicity on locomotor ability in larval zebrafish than V-PS. Motor neuron development was disrupted by transgenic (hb9-GFP) zebrafish larvae exposed to A-PS, with significant alterations in neurotransmitter levels (ACh, DA, 5-HT, and GABA) and enzyme activity (AChE, ChAT, and ChE). Further investigation found that exposure to A-PS had a significantly impact on the expression of neurotransmission and neurodevelopment-related genes in zebrafish. These findings suggest that A-PS induces neurotoxicity by its effects on neurotransmission and neurodevelopment. This study highlights the neurotoxic effects and mechanisms of simulated sunlight irradiation of MPs, providing new insights for assessing the ecological risks of photoaged MPs in the environment.

Environmental concentrations of microplastic-induced gut microbiota and metabolite disruption in silkworm, Bombyx mori

Microplastics (MPs) existing extensively in various ecosystems can be ingested by marine organisms and enter the food chain, resulting the health risks from the presence of MPs in aquatic and terrestrial ecosystems. In the present study, an ideal model for Lepidoptera, the silkworm, Bombyx mori, was exposed to environmental concentrations (0.125 μg, 0.25 μg or 0.5 μg/diet) of MPs for 5 days, and the global changes in gut microbes and metabolites were subsequently examined via 16S rDNA sequencing and GC‒MS-based metabolomics. The results showed that MPs exposure did not seriously threaten survival but may regulate signaling pathways involved in development and cocoon production. MPs exposure induced gut microbiota perturbation according to the indices of α-diversity and β-diversity, and the functional prediction of the altered microbiome and associated metabolites demonstrated the potential roles of the altered microbiome following MPs exposure in the metabolic and physiological states of silkworm. The metabolites markedly altered following MPs exposure may play vital biological roles in energy metabolism, lipid metabolism, xenobiotic detoxification and the immune system by directly or indirectly affecting the physiological state of silkworms. These findings contribute to assessing the health risks of MPs exposure in model insects and provide novel insight into the toxicity mechanism of MPs.

Neurotoxicity of Some Environmental Pollutants to Zebrafish

The aquatic environment encompasses a wide variety of pollutants, from plastics to drug residues, pesticides, food compounds, and other food by-products, and improper disposal of waste is the main cause of the accumulation of toxic substances in water. Monitoring, assessing, and attempting to control the effects of contaminants in the aquatic environment are necessary and essential to protect the environment and thus human and animal health, and the study of aquatic ecotoxicology has become topical. In this respect, zebrafish are used as model organisms to study the bioaccumulation, toxicity, and influence of environmental pollutants due to their structural, functional, and material advantages. There are many similarities between the metabolism and physiological structures of zebrafish and humans, and the nervous system structure, blood-brain barrier function, and social behavior of zebrafish are characteristics that make them an ideal animal model for studying neurotoxicity. The aim of the study was to highlight the neurotoxicity of nanoplastics, microplastics, fipronil, deltamethrin, and rotenone and to highlight the main behavioral, histological, and oxidative status changes produced in zebrafish exposed to them.

Comparison of gut toxicity and microbiome effects in zebrafish exposed to polypropylene microplastics: Interesting effects of UV-weathering on microbiome

Weathered microplastics (MPs) exhibit different physicochemical properties compared to pristine MPs, thus, their effects on the environment and living organisms may also differ. In the present study, we investigated the gut-toxic effects of virgin polypropylene MPs (PP) and UV-weathered PP MPs (UV-PP) on zebrafish. The zebrafish were exposed to the two types of PP MPs at a concentration of 50 mg/L each for 14 days. After exposure, MPs accumulated primarily within the gastrointestinal tract, with UV-PP exhibiting a higher accumulation than PP. The ingestion of PP and UV-PP induced gut damage in zebrafish and increased the gene expression and levels of enzymes related to oxidative stress and inflammation, with no significant differences between the two MPs. Analysis of the microbial community confirmed alterations in the abundance and diversity of zebrafish gut microorganisms in the PP and UV-PP groups, with more pronounced changes in the PP-exposed group. Moreover, the Kyoto Encyclopedia of Genes and Genomes pathway analysis confirmed the association between changes in the gut microorganisms at the phylum and genus levels with cellular responses, such as oxidative stress, inflammation, and tissue damage. This study provides valuable insights regarding the environmental impact of MPs on organisms.

Oral subacute polypropylene microplastics administration effect on potential immunotoxicity in ICR mice

Exposure to microplastics may be associated with damage of immune system. Polypropylene microplastics (PP-MPs) with a wide range of beneficial applications have not been extensively studied with respect to the immune system. The aim of this investigation is to examine the influence of two different sizes of PP-MPs (5.2 and 23.9 μm diameter) on immune system components in ICR mice. PP-MPs were administered orally to female and male mice at 0 (corn oil vehicle), 500, 1000, or 2000 mg/kg/d for single and daily for 4-week repeated toxicity test, respectively. No significant differences were observed in number of thymic CD4+, CD8+, CD4+CD8+ T lymphocytes, splenic helper T cells, cytotoxic T cells, and B cells. The ratio of interferon-γ to interleukin-4 in culture supernatants from activated splenocytes ex vivo (48 hr) was lower in females which were repeatedly administered with PP-MPs compared to vehicle irrespective of PP-MPs size and dose. In contrast, the opposite trend was observed in males. Production of tumor necrosis factor-α was upregulated in females that were repeatedly exposed to PP-MPs. The serum IgG2a/IgG1 ratio was lowered in female receiving large-size PP-MPs. Data suggest that immune disturbances resulting in predominant type-2 helper T cell reactivity may occur in mice, especially in females, when repeatedly exposed to PP-MPs. Further investigations with longer exposure periods are necessary to determine the immunotoxicities attributed to PP-MPs.

Unveiling the Tiny Invaders: A deep dive into microplastics in shrimp - Occurrence, detection and unraveling the ripple effects

Aquaculture is a rapidly expanding food sector worldwide; it is the farming of fish, shellfish, and other marine organisms. Microplastics (MPs) are small pieces of plastic with a diameter of less than 5 mm that end up in the marine environment. MPs are fragments of large plastics that take years to degrade but can frustrate into small pieces, and some commercially available MPs are used in the production of toothpaste, cosmetics, and aircraft. MPs are emerging contaminants; they are ingested by marine species. These MPs have effects on marine species such as growth retardation and particle translocation to other parts of the body. Recently, MPs accumulation has been observed in shrimps, as well as in a wide range of other scientific reports. So, in this study, we review the presence, accumulation, and causes of MPs in shrimp. These plastics can trophic transfer to other organisms, changes in plastic count, effects on the marine environment, and impacts of MPs on human health were also discussed. It also improves our understanding of the importance of efficient plastic waste management in the ocean, as well as the impact of MPs on marine biota and human health.

At-sea solid waste production by a small-scale fishery in Peru

Marine litter is a growing environmental problem for which fisheries-sourced waste remains poorly understood. In Peru, there is an ongoing challenge of waste management from the small-scale fisheries fleet given the lack of facilities to receive the variety of debris produced by fishers, which includes hazardous wastes such as batteries. In this study, onboard solid waste production was monitored daily by land-based observers upon landing at the port of Salaverry, Peru, from March to September 2017. The analysed small-scale gillnet and longline fishing fleets produced annually an estimated 11,260 kg of solid waste. Of particular concern is the production of single use plastics (3427 kg) and batteries (861 kg) due to their potential long-lasting impacts on the environment and challenges related to their proper disposal. A management plan for solid waste has been developed for Salaverry; therefore, a subsequent assessment was conducted in 2021-2022 of the behaviours and perceptions of fishers regarding the implementation of this plan. Most fishers (96%) reported disposing of their waste on land, except organic waste which is disposed of at sea. While fishers in Salaverry have become more conscious of the issues surrounding at-sea waste disposal and have an interest in better segregating and managing their waste, there remains a need for improved waste management and recycling protocols and procedures at the port to make this possible.

Photoelectrocatalytic degradation of high-density polyethylene microplastics on TiO2-modified boron-doped diamond photoanode

Microplastic (MP) accumulation in the environment is accelerating rapidly, which has led to their effects on both the ecosystem and human life garnering much attention. This study is the first to examine the degradation of high-density polyethylene (HDPE) MPs via photoelectrocatalysis (PEC) using a TiO2-modified boron-doped diamond (BDD/TiO2) photoanode. This study was divided into three stages: (i) preparation of the photoanode through electrophoretic deposition of synthetic TiO2 nanoparticles on a BDD electrode; (ii) characterization of the modified photoanode using electrochemical, structural, and optical techniques; and (iii) degradation of HDPE MPs by electrochemical oxidation and photoelectrocatalysis on bare and modified BDD electrodes under dark and UV light conditions. The results indicate that the PEC technique degraded 89.91 ± 0.08% of HDPE MPs in a 10-h reaction and was more efficient at a lower current density (6.89 mA cm-1) with the BDD/TiO2 photoanode compared to electrochemical oxidation on bare BDD.

Plasticizing Pregnancy: Microplastics Identified in Expectant Mothers' Feces

Introduction

Microplastics may be present in food and drinks from various sources, exposing pregnant women to these particles. Consumption of contaminated food can lead to the ingestion of microplastics by pregnant women, potentially causing adverse health effects on the fetus. This study aims to investigate the presence of microplastics in the stools of pregnant women.

Methods

The research was conducted in the Makassar City region of South Sulawesi, Indonesia. Thirty healthy pregnant women from 2 community health centers, Pattingalloang and Jumpandang Baru, participated in the study. Their stools were analyzed using Fourier Transform Infrared (FTIR) microspectroscopy to detect the presence of microplastics.

Result

The analysis revealed the presence of a total of 359 microplastics in the participants' stools, with particle counts ranging from 4 to 21 and sizes ranging from 0.2 to 4.9 mm per 25 g of stool. The polymers identified included Polyethylene Terephthalate (PET), Polyamide/Nylon, Polyethylene Chlorinated, HDPE, and Ethylene Propylene. The amount of microplastics varied significantly among groups with different levels of seafood consumption.

Conclusion

Indonesian pregnant women have been exposed to some microplastic polymers.

Occurrence, transport, and toxicity of microplastics in tropical food chains: perspectives view and way forward

Microplastics, which have a diameter of less than 5 mm, are becoming an increasingly prevalent contaminant in terrestrial and aquatic ecosystems due to the dramatic increase in plastic production to 390.7 million tonnes in 2021. Among all the plastics produced since 1950, nearly 80% ended up in the environment or landfills and eventually reached the oceans. Currently, 82-358 trillion plastic particles, equivalent to 1.1-4.9 million tonnes by weight, are floating on the ocean's surface. The interactions between microorganisms and microplastics have led to the transportation of other associated pollutants to higher trophic levels of the food chain, where microplastics eventually reach plants, animals, and top predators. This review paper focuses on the interactions and origins of microplastics in diverse environmental compartments that involve terrestrial and aquatic food chains. The present review study also critically discusses the toxicity potential of microplastics in the food chain. This systematic review critically identified 206 publications from 2010 to 2022, specifically reported on microplastic transport and ecotoxicological impact in aquatic and terrestrial food chains. Based on the ScienceDirect database, the total number of studies with "microplastic" as the keyword in their title increased from 75 to 4813 between 2010 and 2022. Furthermore, various contaminants are discussed, including how microplastics act as a vector to reach organisms after ingestion. This review paper would provide useful perspectives in comprehending the possible effects of microplastics and associated contaminants from primary producers to the highest trophic level (i.e. human health).

A comprehensive review on the source, ingestion route, attachment and toxicity of microplastics/nanoplastics in human systems

Microplastics (MPs)/nanoplastics (NPs) are widely found in the natural environment, including soil, water and the atmosphere, which are essential for human survival. In the recent years, there has been a growing concern about the potential impact of MPs/NPs on human health. Due to the increasing interest in this research and the limited number of studies related to the health effects of MPs/NPs on humans, it is necessary to conduct a systematic assessment and review of their potentially toxic effects on human organs and tissues. Humans can be exposed to microplastics through ingestion, inhalation and dermal contact, however, ingestion and inhalation are considered as the primary routes. The ingested MPs/NPs mainly consist of plastic particles with a particle size ranging from 0.1 to 1 μm, that distribute across various tissues and organs within the body, which in turn have a certain impact on the nine major systems of the human body, especially the digestive system and respiratory system, which are closely related to the intake pathway of MPs/NPs. The harmful effects caused by MPs/NPs primarily occur through potential toxic mechanisms such as induction of oxidative stress, generation of inflammatory responses, alteration of lipid metabolism or energy metabolism or expression of related functional factors. This review can help people to systematically understand the hazards of MPs/NPs and related toxicity mechanisms from the level of nine biological systems. It allows MPs/NPs pollution to be emphasized, and it is also hoped that research on their toxic effects will be strengthened in the future.

Effects of groundwater sample volume on identified microplastics in groundwater of an agricultural area in Korea

Groundwater serves various purposes worldwide, including agricultural, drinking, domestic, and industrial uses. In the Republic of Korea, groundwater is used primarily for agricultural purpose. Understanding the quality of groundwater is crucial because microplastics (MPs) can enter groundwater through agricultural activities and potentially pose harm to humans. Therefore, groundwater sampling plays a vital role in determining the presence of MPs. However, the optimal volume of groundwater sampling required for accurate MP assessment remains uncertain. This study examined the optimal sample size for collecting MPs from groundwater in the heavy agricultural area of the Haean Basin, Korea. Groundwater sampling and MP analyses were conducted during the wet and dry seasons of 2022. A total of 500 L of groundwater was continuously sampled in increments of 100 L to 500 L (100, 200, 300, 400, and 500 L). Additionally, we investigated the land use surrounding the sampling wells and the predominant types of plastics used in agriculture. To ensure reliable MP analysis, precautions were taken to minimize plastic contact during sampling, pretreatment, and μ-FTIR analysis. The concentration of MPs in groundwater ranged from 0.04 to 17.77 particles/L during the wet season and from 0 to 0.56 particles/L during the dry season. The highest concentration of MPs was observed at the first 100 L sample volume, with concentrations decreasing as the sampling volume increased. Fragmented particles accounted for 86.3 % during the wet season and 91.5 % during the dry season, whereas fibers constituted 13.7 and 8.5 %, respectively. MPs in the size range of 20-100 μm were predominant in both seasons. The polymers identified in both seasons were polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), and polyamide (PA). While some studies suggest that 500 L is the optimal sample volume for assessing MPs in groundwater, the findings of this study indicate that a larger sample volume may be necessary. This study was the first attempt to determine the optimum sample volume required to collect MPs from groundwater, emphasizing the importance of conducting further research to validate these findings.

Interactions between microplastics and Culex sp. larvae in wastewater

Microplastics (MPs) are a growing issue because they endanger both aquatic organisms and humans. Studies have indicated that wastewater treatment plants (WWTPs) are one of the major contributors to MPs in the environment. However, studies on the abundance of MP contamination in WWTPs and its transmission into aquatic organisms are still scarce, especially in Egypt. The goal of this study was to examine the temporal fluctuations in the distribution of MPs in surface water and the dominant macroinvertebrate fauna (Culex sp. larvae) in a fixed wastewater basin in Sohag Governorate, Egypt. The average of MPs in the surface water was 3.01 ± 0.9 particles/L. The results indicated to seasonal variation of MP abundance in the wastewater basin that was significantly higher in winter than in the other seasons. The risk index for polymers (H), pollution load index (PLI), and potential ecological risk index (RI) were used to assess the degree of MP contamination. The basin has moderate H values (<1000) because of the presence of polymers with moderate hazard scores such as polyester (PES), polyethylene (PE), and polypropylene (PP). According to the PLI values, surface water is extremely contaminated with MPs (PLI: 88 to 120). The RI values of surface water showed higher ecological risk (level V). MPs in Culex sp. larvae were seasonally changed with an 85% detection rate, and an abundance average of 0.24 ± 0.65 particles/ind, MP concentration in Culex sp. larvae was influenced by the MP characters (shape, color, and polymer). The larvae of Culex sp. showed a greater preference for black and red fibrous polyester (PES) with sizes (<1000 μm) of MPs. These findings suggest that Culex sp. larvae prefer ingesting MPs that resemble their food. It is possible to overestimate Culex sp.'s preference for lower sizes because of their catabolism of MPs. To better understand the preferences of Culex sp. larvae for MPs, further controlled trials should be conducted. PRACTITIONER POINTS: Wastewater is highly contaminated with microplastics (MPs) in the different seasons. First report of detection of the seasonal abundance of MP in Culex sp. larvae. Culex sp. larvae showed a stronger feeding preference for MPs with specific characteristics. Smaller size and blue polyester fibers were the dominant characteristics of MPs in wastewater.

Comparison of chlorination resistance of biodegradable microplastics and conventional microplastics during the disinfection process in water treatments

Nowadays, microplastics (MPs) widely exist in the environment, and water treatment plants are important sources of MPs. Chlorine is widely used in the disinfection process in water treatment plants and has strong oxidation, however, the chemical and physical properties changes of MPs during chlorination were unclear. Thus, in this study, based on the actual used chlorine concentrations, different chlorination conditions were simulated to study the variation of MPs after chlorination. Meanwhile, the produced disinfection by-products were monitored. The results showed that under high chlorination concentration conditions, functional groups of polyethylene (PE), polystyrene (PS), and polylactic acid (PLA) changed, while no peak shift or change of poly (butyleneadipate-co-terephthalate) (PBAT) could be detected. Moreover, after chlorination, partial yellowing and cracks appeared on PS, PLA, and PBAT, while PE remained white and showed little morphological changes. Besides, chlorination led to the narrowing of the cold crystallization peak and melting peak of PLA, while chlorination had little influence on the crystal structure of PE and PBAT. Furthermore, the reaction between PLA and chlorine mostly produced more trichloromethane than other types of MPs. Consequently, when chlorine concentrations were in the range of 2.5 to 5000 mg/L, the chlorination resistance was PBAT/PE > PLA > PS. Specifically, PBAT had the strongest chlorination resistance in terms of chemical properties, while PE had the strongest chlorination resistance in terms of physical properties. Therefore, the degradability of biodegradable MPs is not higher than that of conventional MPs in all cases. Moreover, it should be noted that most changes occurred only in high chlorine concentrations. Thus, neither conventional MPs nor biodegradable MPs can be completely degraded during the chlorination process in water treatments.

Review of emerging contaminants in green stormwater infrastructure: Antibiotic resistance genes, microplastics, tire wear particles, PFAS, and temperature

Green stormwater infrastructure is a growing management approach to capturing, infiltrating, and treating runoff at the source. However, there are several emerging contaminants for which green stormwater infrastructure has not been explicitly designed to mitigate and for which removal mechanisms are not yet well defined. This is an issue, as there is a growing understanding of the impact of emerging contaminants on human and environmental health. This paper presents a review of five emerging contaminants - antibiotic resistance genes, microplastics, tire wear particles, PFAS, and temperature - and seeks to improve our understanding of how green stormwater infrastructure is impacted by and can be designed to mitigate these emerging contaminants. To do so, we present a review of the source and transport of these contaminants to green stormwater infrastructure, specific treatment mechanisms within green infrastructure, and design considerations of green stormwater infrastructure that could lead to their removal. In addition, common removal mechanisms across these contaminants and limitations of green infrastructure for contaminant mitigation are discussed. Finally, we present future research directions that can help to advance the use of green infrastructure as a first line of defense for downstream water bodies against emerging contaminants of concern.

Microcosm study of the effects of polyester microfibers on the indigenous marine amphipod (Cyphocaris challengeri) in the Strait of Georgia (BC, Canada)

Microplastics (MP) remain contaminants of great concern in the ocean because of their abundance, prevalence, and threat to marine organisms. Still, there is a great need for studies on the impact of MP on marine zooplankton. Here, we investigated the effects of polyethylene terephthalate (PET) microfibers (Mf) on the survival, Mf ingestion and retention, predation, and fecal pellets (FP) of the marine amphipod (Cyphocaris challengeri) at environmentally relevant concentrations (0, 10, 100, 1000, 10,000 and 50,000 Mf·L-1) and varied exposure time (24, 48 and 72 h). Our study demonstrated that exposure of C. challengeri to PET Mf did not affect their survival. The average number of ingested Mf and the Mf ingestion rate increased significantly with Mf concentrations. Nonetheless, the Mf ingestion rates by C. challengeri decreased significantly between 24 and 72 h in the two highest Mf treatments (10,000 and 50,000 Mf·L-1), suggesting careful rejection of the Mf or reduced feeding activity. Indeed, PET Mf significantly reduced the copepod feeding rate of the amphipods at Mf concentrations ≥1000 Mf·L-1 after 24 and 48 h of exposure duration. Over time, prey intake reduction in amphipods due to Mf ingestion could affect their reproductive outcome, growth, development, and cellular and ecosystem function. The encapsulation of PET Mf into the FP of C. challengeri significantly increased the FP density and sinking velocities, ultimately doubling the transfer rate of the FP from the surface waters to the sediments in SoG. Conversely, ingesting PET microfibers and their incorporation in FP will potentially enhance the role of C. challengeri in the biological C pump and sequestration in SoG. Our study showed that changes in Mf concentration had a more significant effect on C. challengeri Mf ingestion and ingestion rate, prey consumption, FP density and sinking velocity than the exposure time.

Risks Associated with the Presence of Polyvinyl Chloride in the Environment and Methods for Its Disposal and Utilization

Plastics have recently become an indispensable part of everyone's daily life due to their versatility, durability, light weight, and low production costs. The increasing production and use of plastics poses great environmental problems due to their incomplete utilization, a very long period of biodegradation, and a negative impact on living organisms. Decomposing plastics lead to the formation of microplastics, which accumulate in the environment and living organisms, becoming part of the food chain. The contamination of soils and water with poly(vinyl chloride) (PVC) seriously threatens ecosystems around the world. Their durability and low weight make microplastic particles easily transported through water or air, ending up in the soil. Thus, the problem of microplastic pollution affects the entire ecosystem. Since microplastics are commonly found in both drinking and bottled water, humans are also exposed to their harmful effects. Because of existing risks associated with the PVC microplastic contamination of the ecosystem, intensive research is underway to develop methods to clean and remove it from the environment. The pollution of the environment with plastic, and especially microplastic, results in the reduction of both water and soil resources used for agricultural and utility purposes. This review provides an overview of PVC's environmental impact and its disposal options.

Advances on micro/nanoplastics and their effects on the living organisms: A review

Micro/nanoplastics (MPs) are attracting increasing attention owing to the potential threats they pose to the sustainability of the environment and the health of living organisms. Thus, a comprehensive understanding of the influence of MPs on living organisms is vital for developing countermeasures. We conducted an extensive literature search to retrieve the articles related to MPs via the Web of Science. Accordingly, 152 articles published in the last decade and in influential journals were selected to analyze the effects of MPs on plants, animals, microorganisms, and humans as well as the current status, hotspots, and trends of studies on MPs. The results showed that owing to the special characteristics of MPs and anthropogenic activities, MPs have become ubiquitous worldwide. MPs are ingested by plants and animals and enter the human body through various pathways, resulting in numerous adverse effects, such as growth inhibition, oxidative stress, inflammation, organ damage, and germ cell lesions. Moreover, they affect microorganisms by reshaping the structure and function of microbial communities and changing the spread pathway. However, microorganisms can also contribute to the degradation of MPs. With increasing evidence of the adverse effects of MPs on biota, coping with MP pollution and mitigating harmful outcomes have emerged as major challenges. This review focuses on (1) the main effects of MPs on living organisms, ranging from microorganisms to humans, (2) the current status and hotspots of studies related to MPs, and (3) the challenges and prospects of further studies on MPs.