Microplastics pollution and risk assessment in water bodies of two nature reserves in Jilin Province: Correlation analysis with the degree of human activity

Distribution, characteristics, and ecological risks of microplastics in the Hongyingzi sorghum production base in China

Microplastics (MPs), an emerging pollutant of global concern, have been studied in the Hongyingzi sorghum production base. In this study, we investigated MPs in the surface soil (0-10 cm) and deeper soil (10-20 cm) in the Hongyingzi sorghum production base. Pollution characterization and ecological risk evaluation were conducted. The results revealed that the MP abundance ranged from 1.31 × 102 to 4.27 × 103 particles/kg, with an average of 1.42 ± 1.22 × 103 particles/kg. There was no clear correlation between the MP abundance and soil depth, and the ordinary kriging method predicted a range of 1.26 × 103-1.28 × 103 particles/kg in most of the study area, indicating a relatively uniform distribution. Among the 12 types of MPs detected, acrylates copolymer (ACR), polypropylene (PP), polyurethane (PU), and polymethyl methacrylate (PMMA) were the most frequently detected. These MPs primarily originated from packaging and advertising materials made from polyurethane and polyester used by Sauce Wine enterprises, as well as plastic products made from polyolefin used in daily life and agricultural activities. The particle size of MPs was primarily 20-100 μm. Overall, the proportion of the 20-100 μm MP was 95.1% in the surface soil layer and 86.7% in the deeper soil layer. Based on the pollution load index, the MP pollution level in the study area was classified as class I. Polymer hazard index evaluation revealed that the risk levels at all of the sampling sites ranged from IV to V, and ACR, PU, and PMMA were identified as significant sources of polymer hazard. Potential ecological index evaluation revealed that most of the soil samples collected from the study area were dangerous or extremely dangerous, and the surface soil posed a greater ecological risk than the deeper soil. These findings provide a scientific foundation for the prevention, control, and management of MP pollution in the Hongyingzi sorghum production base.

Abundance, characteristics and ecological risks of microplastics from South Yellow Sea Mudflat

Microplastic (MP) pollution in global marine environments has been extensively reported and attracted significant concerns, but MP distribution in mudflat has rarely been studied. In this paper, the abundance, features and ecological risk of MP in South Yellow Sea Mudflat were investigated comprehensively. MP were both detected in waters (5.4 ± 0.38-11.3 ± 0.78 items/L) and sediments (5.1 ± 0.36-10.1 ± 0.69 items/g) from South Yellow Sea Mudflat. There existed different MP abundance tendencies from sampling Group I (coastal estuary or port) and II (purely coastal mudflat), while MP abundance in water from Group II was lower than that from Group I generally, but MP abundance in sediment from Group I was lower than that from Group II generally. This suggested that MP abundance in mudflat water could be associated with frequent human activities significantly, and disturbance might not be beneficial to MP accumulation in sediments. Fragments, transparent, polyethylene (PE), polypropylene (PP) and polystyrene (PS) were major MP features in mudflat water and sediment, and maximum proportion of size of MP was 0.001-0.25 mm in both water and sediment. Furthermore, the primary risk assessment indicated that MP pollution load for mudflat was low level. However, potential MP ecological risk for mudflat could reach dangerous level to very dangerous level by calculating and evaluating polymer risk index (PRI) and potential ecological risk index (PERI), which could be caused by high proportions of polyvinyl chloride (PVC) and polyacrylonitrile (PAN) with high hazard score. For the first time, reference data about MP pollution from South Yellow Sea Mudflat were supplied in this paper, which would be helpful for management and control of MP in mudflat.

Exposure to polystyrene nanoplastics causes immune damage, oxidative stress and intestinal flora disruption in salamander (Andrias davidianus) larvae

The toxic effects of nanoparticles have been increasingly investigated, but there has been limited research on amphibians, especially those of conservation value. This study examined the effects of different concentrations (0, 0.04, 0.2, 1, 5 mg/L) of polystyrene nanoplastics (PS-NPs, 80 nm) on the short-term exposure (7 d) of Andrias davidianus. Results demonstrated the concentration-dependent enrichment of PS-NPs in the intestine. Histological lesions displayed increased hepatic macrophages with cellular rupture, broken intestinal villi, decreased cuprocytes and crypt depression. Antioxidant- and inflammation-related enzyme activities were analysed, and it was found that hepatic and intestinal MDA content and CAT activity were highest in the N-1 group and SOD activity was highest in the N-0.2 group (p < 0.05). AKP activity continued to decline, and iNOS activity was highest in the N-0.2 group (p < 0.05). il-10, tgf-β, bcl-w and txnl1 were significantly downregulated in the N-0.2 group, while il-6 and il-8 were markedly upregulated in the N-0.2 group (p < 0.05). Exposing to PS-NPs decreased probiotic bacteria (Cetobacterium, Akkermansia) and increased pathogenic bacteria (Lachnoclostridium). Our results suggest that NPs exposure can have deleterious effects on salamanders, which predicts that NPs contamination may lead to continued amphibian declines. Therefore, we strongly recommend that attention be paid to amphibians, especially endangered species, in the field of NPs.

Assessing the abundance, sources, and potential ecological risk assessment of microplastics using their particle and mass units in Uiam Lake, South Korea

Microplastics (MPs) enter lakes through various pathways, including effluents from wastewater treatment plants (WWTPs), surface runoff, and improperly disposed of plastic waste. In this study, the extent of MPs pollution in Uiam Lake in fall of 2022 and spring of 2023 was assessed by determining both the number (n/m3) and mass concentrations (μg/m3) of MPs. Moreover, the correlation between water quality parameters and MP properties was analyzed, and an ecological risk assessment was conducted. MPs abundance was higher in spring than in fall, probably due to the lifting of coronavirus disease-19 restrictions, melting of ice, higher rainfall, and faster wind speed. Fragment was the dominant shape of the MPs collected, while polyvinyl chloride (PVC) and polyester/polyethylene terephthalate were the frequently detected polymer types of MPs in fall and spring, respectively. There was a moderate positive correlation between the number concentration of MPs and the total nitrogen, total phosphorus (T-P), and total organic carbon levels; in contrast, there was no significant relationship between the mass concentration of MPs and all water quality parameters. However, the abundance (μg/m3) of PVC and polymethyl methacrylate MPs were positively correlated with T-P and electrical conductivity. The pollution load index, polymer hazard index, and potential ecological risk index (PERI) were generally higher when the mass unit of MPs was used due to the presence of large-sized MPs composed of highly hazardous polymers (e.g., polyurethane, PVC, and alkyd). For instance, the PERI value of the WWTP effluent was at the very high level (>1200) in both seasons, regardless of the abundance unit of MPs. Therefore, WWTP effluents may have increased the ecological toxicity of MPs pollution in Uiam Lake.

Spatiotemporal variation of water level in wetlands based on multi-source remote sensing data and responses to changing environments

Under changing environmental conditions, water level is a crucial indicator for assessing the wetland hydrological cycle. However, due to some wetlands being located in remote and widely dispersed areas, acquiring data on wetland water level changes presents significant challenges, making wetland water level monitoring exceptionally difficult. Wetlands are extensively distributed in western Jilin Province, China, and are experiencing significant degradation due to various factors including natural conditions, agricultural activities, and social development. To address this challenge, this study proposes a monitoring method that combines Sentinel-3 radar altimetry satellites with optical remote sensing images to obtain wetland water level data. Additionally, the study takes into account the Chinese government's Interconnected River System Network Project (IRSNP), classifying wetlands in western Jilin Province into three different water recharge scenarios: direct recharge through main and branch canals, indirect recharge through ditches, and no recharge to isolated wetlands. This study analyses the relationship between wetland water level changes and climatic factors, and assesses how IRSNP can mitigate the negative impacts of climate factors on wetland water levels across different recharge scenarios. The results show that: (1) the wetland water level monitoring method, has high accuracy and feasibility. The average difference between the in-situ measured and satellite-monitored water levels was 0.254 m. (2) There was an overall increasing trend in wetland water levels directly influenced by IRSNP, an insignificant decreasing trend in wetland water levels indirectly influenced by IRSNP. (3) Increased precipitation and decreased evaporation are the predominant climatic factors contributing to rising wetland water levels. Conversely, lower relative humidity and higher temperatures primarily lead to declining water levels. The construction of IRSNP can mitigate the impact of climate change on water levels. Thus, under changing environmental conditions, the implementation of IRSNP has positively impacted wetland protection and provides valuable insights for understanding wetland water level changes and managing water resources effectively.

Morphometric characteristics and spatiotemporal heterogeneity of microplastics on the north-east coast of India

The study analysed microplastics (MPs) in surface waters along the north-east coast of India and focused on the spatiotemporal distribution and morphometric characteristics of 800 particles for environmental insights. The MPs were consistently present in all water masses, with an average abundance of 0.67 ± 0.66 particles/m3 during the monsoon and 0.12 ± 0.08 particles/m3 post-monsoon. Fragments and fibers were dominant in both seasons, comprising over 83 % and 12 %, respectively. In terms of colours, blue was significantly dominant during the post-monsoon (H, χ2 (5) = 15.38, p < 0.01); however, such variation was absent during the monsoon. Spatially, significant variance in abundance (F4, 34 = 8.542; p < 0.01) and across colours and forms during the monsoon was correlated with land-based inputs from the Hooghly River. FTIR analysis revealed ten polymer types, predominantly polyethylene (44 %). SEM observations indicated that 80 % of particles exhibited polymer ageing from oxidative weathering. The size distribution of MPs varied notably, with a higher proportion of < 0.3 mm (16.7 %) during the monsoon, possibly due to increased particle disintegration. The study noted MPs had low to moderate circularity, with increased irregularity during the monsoon due to heavy precipitation and river flushing. An initial risk assessment of MP pollution in surface waters on the north-east coast revealed a low-risk state. Acrylonitrile butadiene styrene (ABS) was identified as the most hazardous MP polymer. A wide range of toxic trace elements were found in MPs in these waters. The findings from the study deepen our knowledge of MPs and their fate in the pelagic zone, which supports the development of science-based policies that effectively reduce MP pollution.

Factors influencing the distribution, risk, and transport of microplastics and heavy metals for wildlife and habitats in "island" landscapes: From source to sink

Microplastics (MPs) and heavy metals (HMs) are important pollutants in terrestrial ecosystems. In particular, the "island" landscape's weak resistance makes it vulnerable to pollution. However, there is a lack of research on MPs and HMs in island landscapes. Therefore, we used Helan Mountain as the research area. Assess the concentrations, spatial distribution, ecological risks, sources, and transport of MPs and HMs in the soil and blue sheep (Pseudois nayaur) feces. Variations in geographical distribution showed a connection between human activity and pollutants. Risk assessment indicated soil and wildlife were influenced by long-term pollutant polarization and multi-element inclusion (Igeo, Class I; PHI, Class V; RI (MPs), 33 % Class II, and 17 % Class IV; HI = 452.08). Source apportionment showed that tourism and coal combustion were the primary sources of pollutants. Meanwhile, a new coupling model of PMF/Risk was applied to quantify the source contribution of various risk types indicated transportation roads and tourism sources were the main sources of ecological and health risks, respectively. Improve the traceability of pollution source risks. Furthermore, also developed a novel tracing model for pollutant transportation, revealing a unique "source-sink-source" cycle in pollutant transportation, which provides a new methodological framework for the division of pollution risk areas in nature reserves and the evaluation of spatial transport between sources and sinks. Overall, this study establishes a foundational framework for conducting comprehensive risk assessments and formulating strategies for pollution control and management.

Occurrence, potential sources, and ecological risk assessment of microplastics in the inland river basins in Northern China

Microplastics (MPs) are the pollutants, found widely across various environmental media. However, studies on the MP pollution in urban rivers and the necessary risk assessments remain limited. In this study, the abundance and characteristics of microplastics in a typical urban river were examined to evaluate their distribution, sources, and ecological risks. It was observed that the abundance of MPs in sediments (220-2840 items·kg-1 dry weight (DW)) was much higher than that in surface water (2.9-10.3 items·L-1), indicating that the sediment is the "sink" of river MPs. Surface water and sediment were dominated by small particle size MPs (< 0.5 mm). Fiber and debris were common shapes of MPs in rivers and sediments. The microplastics in river water and sediments were primarily white and transparent, respectively. Polypropylene (PP) and polyethylene (PE) were the major polymers found.

Microplastic pollution and ecological risk assessment of a pond ecosystem

Microplastic (MP) pollution has been observed in various ecosystems as a result of the rapid increase in plastic production over the past half-century. Nevertheless, the extent of MP pollution in different ecosystems, particularly in freshwater ecosystems, has not been well-studied, and there are limited investigations on this particular topic, specifically in Türkiye. Here, we quantify the occurrence and distribution of MPs in surface water samples collected from Topçu Pond (Türkiye) for the first time. Water samples were collected at five stations and filtered (30 L for each station) through stacked stainless steel sieves (5 mm, 328 µm, and 61 µm mesh size) with a diameter of 30 cm. The abundance, size, color, shape, and type of collected debris samples were analyzed after the wet peroxide oxidation process. MP particles were observed in all samples at an average abundance of 2.4 MPs/L. The most abundant MP size class and type were 0-999 µm and fiber respectively. On the other hand, prevalent colors were black and colorless in general. According to the Raman analysis results, the identified MP derivatives were polypropylene (40%), polyamide (30%), ethylene acrylic acid (20%), and polyvinylchloride (10%). Moreover, the pollution load index (PLI) index was used to determine the pollution status. PLI values were determined as 1.91 at station S1, 1.73 at station S2, 1.31 at station S3, 1 at station S4 and 1.24 at station S5. The PLI value determined for the overall pond was 1.4. The results of this research show that MP pollution is present in Topçu Pond and contributes to the expanding literature on MP pollution in pond ecosystems.

Real-Time Detection of Microplastics Using an AI Camera

Microplastics (MPs, size ≤ 5 mm) have emerged as a significant worldwide concern, threatening marine and freshwater ecosystems, and the lack of MP detection technologies is notable. The main goal of this research is the development of a camera sensor for the detection of MPs and measuring their size and velocity while in motion. This study introduces a novel methodology involving computer vision and artificial intelligence (AI) for the detection of MPs. Three different camera systems, including fixed-focus 2D and autofocus (2D and 3D), were implemented and compared. A YOLOv5-based object detection model was used to detect MPs in the captured image. DeepSORT was then implemented for tracking MPs through consecutive images. In real-time testing in a laboratory flume setting, the precision in MP counting was found to be 97%, and during field testing in a local river, the precision was 96%. This study provides foundational insights into utilizing AI for detecting MPs in different environmental settings, contributing to more effective efforts and strategies for managing and mitigating MP pollution.

Pollution characteristics and prospective risk of microplastics in the Zhengzhou section of Yellow River, China

The ubiquitous occurrence of microplastics (MPs) in the freshwater has attracted widespread attention. The Zhengzhou section of the Yellow River was the most prosperous region in ancient China, and the rapid urbanization, industrialization, and agricultural practices contributed to MPs pollution in aquatic systems recently, whereas the contamination status of MPs in the area is still not available. In this study, a total of fourteen sampling cross-sections were selected in the region to collect water samples systematically for the analysis of MPs pollution characteristics and potential risks. Results showed that abundance of MPs in the water were ranged from 2.33 to 15.50 n/L, with an average value of 6.40 ± 3.40 n/L, which was higher than it in other inland rivers from China. Moreover, the MPs of 0.5-2 mm were the dominant sizes in Yellow River of Zhengzhou region, and most of them were black fibres. The top three polymers were Polyethylene terephthalate (PET), Polyamide (PA) and Polypropylene (PP). High diversity indices of MPs observed at S3, S4, S5, S6, S7, and S8 for size, colour, polymer and shape indicated diverse and complex sources of MPs in those cross-sections. The MPs in water from Zhengzhou area of Yellow River probably degraded from textiles, fishing net, plastic bags, mulching film, packaging bags, and tire wear. The chemical risk assessment revealed a level III risk for study area, while S8 and S11 in which PVA or PAN with higher hazard score detected were categorised as class V risk. Coincidentally, probabilistic risk assessment showed a considerable ecological risk of MPs from Yellow River in Zhengzhou City, with possibility of 99.48 and 98.01 % adverse effect for food dilution and translocation-mediated mechanism, respectively. The results are expected to assistance for development of policies and ultimately combating MPs pollution.

Understanding microplastic presence in different wastewater treatment processes: Removal efficiency and source identification

Municipal effluents discharged from wastewater treatment plants (WWTPs) are a considerable source of microplastics in the environment. The dynamic profiles of microplastics in treatment units in WWTPs with different treatment processes remain unclear. This study quantitatively analyzed microplastics in wastewater samples collected from different treatment units in two tertiary treatment plants with distinct processes. The influents contained an average of 15.5 ± 3.5 particles/L and 38.5 ± 2.5 particles/L in the two WWTPs with in the oxidation ditch process and the integrated fixed-film activated sludge process, respectively. Interestingly, microplastic concentrations in the influent were more influenced by the population density in the served area than sewage volume or served population equivalent. Throughout the treatment process, concentrations were reduced to 1.5 ± 0.5 particles/L and 1.0 ± 1.0 particles/L in the final effluents, representing an overall decrease of 90% and 97%, in WWTPs with the oxidation ditch process and integrated fixed-film activated sludge process, respectively. A significant proportion of the microplastics were removed during the primary treatment stage in both WWTPs, with better performance for foam, film, line-shaped and large-sized microplastics. Most microplastics were accumulated in activated sludge, indicating its key role as the primary sink in WWTPs. The multiple correspondence analysis identified laundry washing and daily necessities such as packaging and containers as the major contributors to microplastics in WWTPs. The study proposed recommendations for upgrading WWTPs, modifying designs, and implementing strategies to reduce microplastic sources, aiming to minimize the release of microplastics into the environment. These findings can shed lights on the sources of microplastics in WWTPs, and advance our understanding of the mechanisms for more effective microplastic removals in wastewater treatment technologies in future applications.

Microplastics in drinking water: A review on methods, occurrence, sources, and potential risks assessment

Microplastics in drinking water captured widespread attention following reports of widespread detection around the world. Concerns have been raised about the potential adverse effects of microplastics in drinking water on human health. Given the widespread interest in this research topic, there is an urgent need to compile existing data and assess current knowledge. This paper provides a systematic review of studies on microplastics in drinking water, their evidence, key findings, knowledge gaps, and research needs. The data collected show that microplastics are widespread in drinking water, with large variations in reported concentrations. Standardized methodologies of sampling and analysis are urgently needed. There were more fibrous and fragmented microplastics, with the majority being <10 μm in size and composed of polyester, polyethylene, polypropylene, and polystyrene. Little attention has been paid to the color of microplastics. More research is needed to understand the occurrence and transfer of microplastics throughout the water supply chain and the treatment efficiency of drinking water treatment plants (DWTPs). Methods capable of analyzing microplastics <10 μm and nanoplastics are urgently needed. Potential ecological assessment models for microplastics currently in use need to be improved to take into account the complexity and specificity of microplastics.

Occurrence and fate of microplastics from a water source to two different drinking water treatment plants in a megacity in eastern China

The widespread presence of microplastics (MPs) contamination in drinking water has raised concerns regarding water safety and public health. In this study, a micro-Raman spectrometer was used to trace the occurrence of MP transport from a water source to a drinking water treatment plant (DWTP)1 with an advanced treatment process and DWTP2 with a conventional treatment process and the contributions of different processes to the risk reduction of MPs were explored. Six types of MPs were detected: polyethylene terephthalate, polyethylene, polypropylene, polystyrene, polyamide, and polyvinyl chloride. 2-5 μm (35.8-41.2%) and polyethylene terephthalate (27.1-29.9%) were the most frequently detected MP sizes and types of water source samples, respectively. The abundance of MPs in treated water decreased by 72.7-83.0% compared to raw water. Ozonation and granular activated carbon (52.7%), and sand filtration (47.5%) were the most effective processes for removing MPs from DWTP1 and DWTP2, respectively. Both DWTPs showed significant removal effects on polyethylene terephthalate, with 80.0-88.1% removal rates. The concentrations of polystyrene increase by 30.0-53.4% after chlorination. The dominant components in the treated water of DWTP1 and DWTP2 were polypropylene (24.7%) and polyethylene 27.7%, respectively, and MPs of 2-5 μm had the highest proportion (55.3-64.3%). Pollution load index and potential ecological risk index of raw water treated by DWTPs were reduced by 48.0-58.7% and 94.5-94.7%, respectively. The estimated daily intake of MPs in treated water for infants was 45.5-75.0 items/kg/d, respectively, approximately twice that of adults. This study contributes to the knowledge gap regarding MP pollution in drinking water systems.

Polystyrene microplastics mediate cell cycle arrest, apoptosis, and autophagy in the G2/M phase through ROS in grass carp kidney cells

Microplastics (MPs) have attracted widespread worldwide attention as a new pollutant. However, the role of reactive oxygen species (ROS) and cell cycle in nephrotoxicity induced by different concentrations of polystyrene microplastics (PS-MPs) is unknown. This study used grass carp kidney cells (CIK) treated with different concentrations of PS-MPs (0, 0.012, 0.0625, and 0.5 mg L-1 ) as subjects. With the increase of PS-MPs concentration, the levels of ROS and malonaldehyde increased, while the level of total antioxidant capacity, superoxide Dismutase (SOD), and glutathione (GSH) activity decreased. The expression of BUB1 mitotic checkpoint serine/threonine kinase (BUB1), cyclin-dependent kinase (CDK1), CDK2, CyclinB1, cell division cycle 20 homolog (CDC20), and B-cell lymphoma-2, sequestosome 1 decreased significantly. Nevertheless, the expression of Caspase 3, Cleave-Caspase 3, cytochrome c (Cytc), BCL2-associated X, apoptosis regulator, poly ADP-ribose polymerase (PARP), Cleave-PARP, Caspase 9, autophagy immunoblot kit (LC3), and Beclin1 increased. Our research shows that PS-MPs can trigger oxidative stress and induce cell cycle arrest, apoptosis, and autophagy in CIK cells by regulating ROS. This work provides a theoretical basis for cellular biology and toxicology mechanisms and new insights into the potential risks to animals from MPs exposure in the environment.

Unraveling the land-based discharge of microplastics from sewers to oceans - A comprehensive study and risk assessment in wastewaters of Goa, India

Owing to their pervasive dispersion in the environment and their potential ramifications on both marine life and human health, microplastics (MPs) are of increasing concern. However, there is still a lack of research on the release of MPs from different land-based pathways like creeks, drainage outfalls, and conduits into coastal water systems in India. This study represents comprehensive research into the attribution of MPs in the estuarine system, specifically those emanating from wastewater sources in Panjim City, Goa, India. Urban wastewater collected from different locations in and around Panjim City exhibited values ranging from 79 ± 21 to 338 ± 7 MPs/L, with a prevalence of fibrous and black MP particles. The size range of the MPs at all sampling sites was 100-300 μm. Analysis by μ-FTIR revealed 35 distinct polymeric compositions in wastewater, with a dominance of polyacrylamide (PAM), polyvinyl chloride (PVC), and polyamide (PA). Additionally, primary and secondary MPs were studied to unravel the contributions from land-based sources. This included the quantification of MPs in ten samples from personal care products (PCPs) and twenty samples from washing machine effluents (WMEs). MPs in PCPs ranged from 1.8 to 1554 MPs/g. Microfibres and fragments were predominant in WMEs (3986 to 4898 MPs/L). This study suggests a strong relation between polymers found in wastewater effluent and those present in PCPs and WMEs. The identified polymers showed high polymer hazard indices (IV and V), posing a significant threat to the ecosystem and a potential risk to human health.

Evaluation of microplastic pollution and risk assessment in a tropical monsoonal estuary, with special emphasis on contamination in jellyfish

Estuaries, which serve as vital links between land and coastal ecosystems, play a significant part in facilitating the transfer of plastic waste from the land to the ocean. In this research, we examined the prevalence, characteristics, and ecological risks of microplastics (MPs) in the extensively urbanized Cochin Estuarine System (CES), India. Additionally, it represents one of the initial evidence-based examinations of MPs ingestion by jellyfish in Indian waters, focusing on Acromitus flagellatus, Blackfordia virginica, and Pleurobrachia pileus species. The abundance of MPs found in the surface water of the Cochin Estuarine System (CES) varied between 14.44 ± 9 to 30 ± 15.94 MP/m3, with an average of 21.6 ± 11 MP/m3. In both surface waters and jellyfish from the Cochin Estuarine System (CES), fibers were the most prevalent type of MPs, with polyethylene (PE), polypropylene (PP), and polyamide (PA) being the most common polymer varieties. To evaluate the current levels of MPs and their effect on the CES, the Pollution Load Index (PLI), Potential Ecological Risk Index (PERI), and Polymeric Risk Index (H) were utilized. The high PLIestuary values (20.33), high Hestuary values (234.02), and extreme PERIestuary value (1646.06) indicate that the CES is facing an extreme ecological risk. Among the 280 jellyfish individuals examined, 118 (42.14%) were recognized to contain MPs with an average of 1.54 ± 2.68 MPs/individual. Pearson bivariate analysis revealed a significant correlation between the jellyfish bell size and number of plastics per individual. Comparison between jellyfish species revealed, the majority (66%) of the MPs identified in jellyfish were from A. flagellatus and 44 among the 50 jellyfish examined (88%) had MPs. These findings suggest that A. flagellatus may be a potential sink for MPs and may be utilized to be a bioindicator for monitoring MPs contamination in estuarine systems, aiding in future plastic pollution mitigation efforts.

A review of microplastic threat mitigation in Asian lentic environments

Microplastic (MP) pollution has evolved into a significant worldwide environmental concern due to its widespread sources, enduring presence, and adverse effects on lentic ecosystems and human well-being. The growing awareness of the hidden threat posed by MPs in lentic ecosystems has emphasized the need for more in-depth research. Unlike marine environments, there remain unanswered questions about MP hotspots, ecotoxic effects, transport mechanisms, and fragmentation in lentic ecosystems. The introduction of MPs represents a novel threat to long-term environmental health, posing unresolved challenges for sustainable management. While MP pollution in lentic ecosystems has garnered global attention due to its ecotoxicity, our understanding of MP hotspots in lakes from an Asian perspective remains limited. Hence, the aim of this review is to provide a comprehensive analysis of MP hotspots, morphological attributes, ecotoxic impacts, sustainable solutions, and future challenges across Asia. The review summarizes the methods employed in previous studies and the techniques for sampling and analyzing microplastics in lake water and sediment. Notably, most studies concerning lake microplastics tend to follow the order of China > India > Pakistan > Nepal > Turkey > Bangladesh. Additionally, this review critically addresses the analysis of microplastics in lake water and sediment, shedding light on the prevalent net-based sampling methods. Ultimately, this study emphasizes the existing research gaps and suggests new research directions, taking into account recent advancements in the study of microplastics in lentic environments. In conclusion, the review advocates for sustainable interventions to mitigate MP pollution in the future, highlighting the presence of MPs in Asian lakes, water, and sediment, and their potential ecotoxicological repercussions on both the environment and human health.

Bioaccumulation of microplastics in the edible tissues of fish collected from urban lakes of Bangladesh: a potential exposure to public health

Microplastic (MP) pollution is an emerging environmental problem, due to its universal dispersion. In the present study, we determined the MP pollution in water, sediment, and fish samples of three different urban lakes of Bangladesh to assess the bioaccumulation of MPs from the lake environment to fish's edible (flesh) and inedible tissue (gut), ecological risk and consequent human exposure to MPs by fish consumption. A total of forty-three fishes were collected from Jahangirnagar Co-Operative Housing Society (JCHS), Dhanmondi Lake (DL), and Saturia Thana Lake (MST). The average MP concentration in sediment and water of the lakes is 7588 ± 4353 MPs/kg dry weights; 142 ± 22 MPs/L, respectively. MPs were identified in the edible (2.8-20.2 MPs/g) and inedible (2.27-20.93 MPs/g) tissue of all fish species. The highest number of MPs was observed in the flesh of Labeo bata of the JCHS Lake and in the gut of Catla catla of DL. The most dominant shape of MPs was fiber and fragment, 0.1-0.4 mm was the dominant size range, and blue, purple, and transparent were the dominant colors. The presence of six polymer types was revealed by FT-IR analysis, which were polystyrene, polypropylene, nitrile, ethylene vinyl acetate, high-density polyethylene, and nylon. The concentration of MPs in fish is found to increase with the increment in body weight. The bioconcentration factor (BCF) analysis reveals that among all the fish species, Labeo bata and Oreochromis mossambicus accumulate the highest number of MPs from the lake environment. The pollution load index of MPs indicates that the sampling sites were within hazard levels III-IV. Estimated annual intake reveals that humans will be exposed to the highest number of MPs if they consume the flesh of Labeo bata of DL and JCHS Lake.

Microplastic pollution in water environment of typical nature reserves and scenery districts in southern China

Microplastics were frequently detected in the ocean, freshwater environment and wastewater treatment plants. This study aims to fill up the knowledge gap of microplastic distribution in nature reserves and scenery districts. Microplastic samples were collected, the distribution characteristics were analyzed with a stereoscopic microscope and a Fourier transform infrared spectrometer, and the ecological risks of microplastic pollution were calculated. Microplastics were detected in all the collected water samples and the average abundances of microplastics in the surface water of eleven investigated nature reserves and scenery districts ranged from 542 to 5500 items/m3. The degrees of microplastic pollution of all the surveyed nature reserves and scenery districts were classified as hazard level I. Fiber microplastics represented the largest average proportion (67.4 %) and 91.7 % of the detected microplastics were smaller than 2 mm. Corresponding to the frequent detection of fiber microplastics, cotton was the most abundant (25.5 %) polymer type of the suspected microplastics, followed by polyamide (PA, 20.6 %), polyester (PET, 17.0 %), and cellulose (15.6 %). For the ecological risk of the microplastic polymers, six, two and three nature reserves and scenery districts were defined to be at hazard level I, II and III, respectively. In brief, microplastic pollution occurred in all the surveyed nature reserves/scenery districts and posed different degrees of ecological risks.

Abundance, characteristics and risk assessment of microplastics in aquatic sediments: A comparative study in the Yellow River and Yellow Sea

The occurrence of microplastics (MPs) in aquatic ecosystems has become an increasingly serious threat to public health. Marine sediments are considered the final recipients of all microplastic pollution from inland rivers, however, whether and how the MPs differ in these two ecosystems remains poorly known due to the divergent MPs detection methods employed in previous studies. Here, we investigated the abundance, size, and types of MPs in sediment samples from the Yellow River and Yellow Sea using laser direct infrared (LDIR), and assessed their ecological risks. The abundance of MPs in the Yellow Sea is 2.9 times higher than that in the Yellow River, with an average abundance of 54813.2 ± 19355.9 and 18780.2 ± 9951.8 particles·kg-1 (dry sediment), respectively. Notably, the predominant polymer types in both sediment environments were silicone, fluororubber, and polypropylene (PP). MPs with sizes < 100 μm accounted for > 90 % of the total MPs number. Risk assessment demonstrated all the sediment environments exhibited high ecological risks. The dominance of small MPs highlighted the importance of using a method with high resolution to delineate the truthful status of MP pollution.

Polystyrene microplastics with different sizes induce the apoptosis and necroptosis in liver through the PTEN/PI3K/AKT/autophagy axis

The production of plastics worldwide has been instrumental in the progress of modern society, while the increasing accumulation of plastics castoff in oceans, soils and anywhere else has become a major pressure source on environmental sustainability and animal health. Meanwhile, from a biological perspective, our understanding of the toxicological fingerprints of plastics, especially microplastics (MPs), is still poor. Here, we reported a phenomenon of hepatotoxicity dominated by MPs in the form of polystyrene (PS), was observed in mice model systems and cellular assays. Apoptosis and necroptosis related to the size of particles were seen upon PS-MPs introduction, as revealed by transmission electron microscopy, fluorescence microscopy, flow cytometry, and quantitative analysis of signaling pathways in vivo and vitro. Collectively, the current study demonstrated that the levels of liver cell injury caused by PS-MPs were negatively correlated with the particle diameters. Small-sized particles (1-10 μm) induced cell death primarily as necroptosis whereas the large-sized particles (50-100 μm) mainly induced apoptosis, which was directly accomplished by PTEN/PI3K/AKT signaling axis and its targeted autophagy flux. More interestingly, inhibition of autophagy not only alleviated PS-MPs-triggered cell death, but also changed the form of death injury to a certain extent. This uncovered crosstalk relationship opens up a new avenue for investigating the biological and toxicological effects of MPs, and may provide important insights for preventing and limiting of health hazards from MPs.

Water quality pollution assessment and source apportionment of lake wetlands: A case study of Xianghai Lake in the Northeast China Plain

Surface water pollution has always posed a serious challenge to water quality management. Improving water quality management requires figuring out how to comprehend water quality conditions scientifically and effectively as well as quantitatively identify regional pollution sources. In this study, Xianghai Lake, a typical lake-type wetland on the Northeast China Plain, was taken as the research area. Based on a geographic information system (GIS) method and 11 water quality parameters, the single-factor evaluation and comprehensive water quality index (WQI) methods were used to comprehensively evaluate the water quality of the lake-type wetland in the level period. Four key water quality parameters were determined by the principal component analysis (PCA) method, and more convenient comprehensive water quality evaluation models, the minimum WQI considering weights (WQImin-w) and the minimum WQI without considering weights (WQImin-nw) were established. The multiple statistical method and the absolute principal component score-multiple liner regression (APCS-MLR) model were combined to analyse the lake pollution sources based on the spatial changes in pollutants. The findings demonstrated that the WQImin-nw model's water quality evaluation outcome was more accurate when weights were not taken into account. The WQImin-nw model can be used as a simple and convenient way to comprehend the variations in water quality in wetlands of lakes and reservoirs. It was concluded that the comprehensive water quality in the study area was at a "medium" level, and CODMn was the main limiting factor. Nonpoint source pollution (such as agricultural planting and livestock breeding) was the most important factor affecting the water quality of Xianghai Lake (with a comprehensive contribution rate of 31.65%). The comprehensive contribution rates of sediment endogenous and geological sources, phytoplankton and other plants, and water diversion and other hydrodynamic impacts accounted for 25.12%, 19.65%, and 23.58% of the total impact, respectively. This study can provide a scientific method for water quality assessment and management of lake wetlands, and an effective support for migration of migratory birds, habitat protection and grain production security.

Dose-effect of polystyrene microplastics on digestive toxicity in chickens (Gallus gallus): Multi-omics reveals critical role of gut-liver axis

INTRODUCTION

Microplastic pollution seriously threatens the health and safety of humans and wildlife. Avian is one of the main species endangered by microplastics. However, the damage mechanism of microplastics to the digestive system of avian is not clear.

OBJECTIVES

The gut-liver axis is a bidirectional channel that regulates the exchange of information between the gut and the liver and is also a key target for tissue damage caused by pollutants. This study aimed to elucidate the digestive toxicity of microplastics in avian and the key role of the gut-liver axis in it.

METHODS

We constructed an exposure model for microplastics in environmental concentrations and toxicological concentrations in chickens and reveal the digestive toxicity of polystyrene microplastics (PS-MPs) in avian by 16S rRNA, transcriptomics and metabolomics.

RESULTS

PS-MPs changed the death mode from apoptosis to necrosis and pyroptosis by upregulating Caspase 8, disrupting the intestinal vascular barrier, disturbing the intestinal flora and promoting the accumulation of lipopolysaccharide. Harmful flora and metabolites were translocated to the liver through the liver-gut axis, eliciting hepatic immune responses and promoting hepatic lipid metabolism disorders and apoptosis. Liver injury involves multiple molecular effects of mitochondrial dynamics disturbance, oxidative stress, endoplasmic reticulum stress, and cell cycle disturbance. Furthermore, metabolomics suggested that caffeine and melanin metabolites may be potential natural resistance substances for microplastics.

CONCLUSION

Taken together, our data demonstrate the digestive damage of PS-MPs in avian, revealing a critical role of the liver-gut axis in it. This will provide a reference for protecting the safety of avian populations.

Micro-algal astaxanthin improves lambda-cyhalothrin-induced necroptosis and inflammatory responses via the ROS-mediated NF-κB signaling in lymphocytes of carp (Cyprinus carpio L.)

Lambda-cyhalothrin (LCY) is a widely used toxic pesticide that causes harmful effects on the immune organs of fish and aquatic species. Micro-algal astaxanthin (MAA), a heme pigment found in haematococcus pluvialis, has been shown to benefit antioxidants and immunity in aquaculture. To investigate how MAA protects carp lymphocytes from LCY-induced immunotoxicity, a model of fish lymphocytes treated with LCY and/or MAA was established. Lymphocytes from carp (Cyprinus carpio L.) were given LCY (80 μM) and/or MAA (50 μM) as a treatment for a period of 24 h. Firstly, LCY exposure resulted in excessive ROS and malondialdehyde production and reduces antioxidant enzymes (SOD and CAT), indicating a reduced capacity of the antioxidant system. Secondly, the results of flow cytometry and AO/EB labeling proved that lymphocytes treated with LCY have a larger ratio of necroptosis. In addition, LCY upregulated the levels of necroptosis-related regulatory factors (RIP1, RIP3 and MLKL) via the ROS-mediated NF-κB signaling pathway in lymphocytes. Thirdly, LCY treatment caused increased secretion of inflammatory genes (IL-6, INF-γ, IL-4, IL-1β and TNF-α), leading to immune dysfunction in lymphocytes. Surprisingly, LCY-induced immunotoxicity was inhibited by MAA treatment, indicating that it effectively attenuated the LCY-induced changes described above. Overall, we concluded that MAA treatment could ameliorate LCY-induced necroptosis and immune dysfunction by inhibiting the ROS-mediated NF-κB signaling in lymphocytes. It provides insights into the protection of farmed fish from agrobiological threats in fish under LCY and the value of MAA applications in aquaculture.

Environmental risk of microplastics in a Mexican coastal lagoon ecosystem: Anthropogenic inputs and its possible human food risk

Coastal lagoons are ecosystems that are considered providers of a variety species of commercial value to the humans. However, they are currently threatened by a variety of anthropogenic-derived impacts, including environmental pollution by microplastics (MPs). For these reasons, it is necessary to identify suitable biomonitors for monitoring MP activities in aquatic environments and for estimating human ingestion of MPs from the consumption of commercial shellfish species. Therefore, our aims were to identify the anthropogenic activities that supply MPs into a coastal lagoon in the southern Gulf of Mexico and their variety; to determine whether oysters (Crassostrea virginica) are suitable biomonitors to perform MPs monitoring activities and to conduct an estimation of how many MPs could a human consume by the ingestion of a commercial portion of oysters harvested in this coastal lagoon. Our results noted that MP concentrations from water and sediment collected in Laguna de Terminos were 210,000 and 11.3 times higher than values reported in other protected areas worldwide. MPs chemical composition revealed that fishing and urban activities supply mainly polyethylene (21.1 %), poly (butadiene) diol (12.6 %) and polyethylene terephthalate (9.5 %). It was also determined that oysters did not reflect the spatial distribution of MPs within the study area and that a human could consume up to 806.1 MPs per 237.1 g serving of an oyster cocktail. Finally, a coastal lagoon polluted with MPs increases the risk of affecting species used for human consumption.

Quantitative analysis and risk assessment to full-size microplastics pollution in the coastal marine waters of Hong Kong

Given the potential risk to the ecosystem, attention has increased in recent decades to the contamination of the aquatic environment by microplastics (MPs). Due to the limitations of conventional analysis methods of MPs, little is known about the size distribution and abundance of a full-size MPs from 1 μm to 5 mm. The present study quantified MPs with size ranges of 50 μm - 5 mm and 1-50 μm in the coastal marine waters from twelve locations in Hong Kong using fluorescence microscopy and flow cytometry respectively, during the end of wet (September 2021) and dry (March 2022) seasons. The average abundance of MPs with size ranges of 50 μm - 5 mm and 1-50 μm from twelve sampling locations marine surface waters were found ranging from 27 to 104 particles L^-1 and 43,675-387,901 particles L^-1 in the wet season respectively, and 13-36 particles L^-1 and 23,178-338,604 particles L^-1 in the dry season respectively. Significant temporal and spatial variations of small MPs abundance might be observed at the sampling locations, which were contributed by the influences of the estuary of Pearl River, sewage discharge points, land structure, and other anthropogenic activities. Based on the MPs abundance information, ecological risk assessment was conducted and revealed that the small MPs (< 10 μm) in coastal marine surface waters may pose potential health risks to aquatic organisms. Additional risk assessments are needed in order to determine whether or not the MPs exposure would cause health risks to the public.

New insights into the distribution, potential source and risk of microplastics in Qinghai-Tibet Plateau

Microplastics (MPs) as emerging contaminants have become a major global concern, however, the distribution and origin of MPs in Qinghai-Tibet Plateau (QTP) and their impacts on ecosystem are poorly known. Hence, we systematically evaluated the profile of MPs on the representative metropolitan locations of Lhasa and Huangshui Rivers and the scenic sites of Namco and Qinghai Lake. The average abundance of MPs in the water samples was 7020 items/m³, which was 34 and 52 times higher than those for the sediment (206.7 items/m³) and soil samples (134.7 items/m³), respectively. Huangshui River had the highest levels, followed by Qinghai Lake, Lhasa River and Namco. Human activities rather than altitude and salinity impacted the distribution of MPs in those areas. Besides the consumption of plastic products by locals and tourists, laundry wastewater and exogenous tributary inputs, the unique prayer flag culture also contributed to the MPs emission in QTP. Notably, the stability and fragment of MPs were crucial for their fate. Multiple assessment models were employed to evaluate the risk of MPs. PERI model took MP concentration, background value and toxicity into account, comprehensively describing the risk differences of each site. The large PVC proportion in Qinghai Lake posed the highest risk. Furthermore, concerns should be raised about PVC, PE and PET in Lhasa and Huangshui Rivers, and PC in Namco Lake. Risk quotient suggested that aged MPs in sediments slowly released biotoxic DEHP and should be cleaned up promptly. The findings offer baseline data of MPs in QTP and ecological risks, providing important support for the prioritization of future control measures.

Recent trends on microplastics abundance and risk assessment in coastal Antarctica: Regional meta-analysis

We investigated sources, abundance and risk of microplastics (MPs) in water, sediments and biota around Antarctica. The concentration of MPs in Southern Ocean (SO) ranged from 0 to 0.56 items/m³ (mean = 0.01 items/m³) and 0-1.96 items/m³ (mean = 0.13 items/m³) in surface and sub-surface water. The distribution of fibers in water was 50%, sediments were 61%, and biota had 43%, which were followed by fragments in the water (42%), sediments (26%), and biota (28%). Shapes of film had lowest concentrations in water (2%), sediments 13%), and biota (3%). Ship traffic, drift of MPs by currents, and untreated waste water discharge contributed to the variety of MPs. The degree of pollution in all matrices was evaluated using the pollution load index (PLI), polymer hazard index (PHI), and potential ecological risk index (PERI). PLI at about 90.3% of locations were at category I followed by 5.9% at category II, 1.6% at category III, and 2.2% at category IV. Average PLI for water (3.14), sediments (6.6), and biota (2.72) had low pollution load (<10). Mean PHI for water, sediments, and biota showed hazards level V with a higher percentage of 84.6% (>1000) and 63.9% (PHI:0-1) in sediments and water, respectively. PERI for water showed 63.9% minor risk, and 36.1% extreme risk. Around 84.6% of sediments were at extreme risk, 7.7% faced minor risk, and 7.7% were at high risk. While 20% of marine organisms living in cold environments experienced minor risk, 20% were in high risk, and 60% were in extreme risk. Highest PERI was found in the water, sediments, and biota in Ross Sea, due to high hazardous polymer composition of polyvinylchloride (PVC) in the water and sediments due to human activity, particularly use of personnel care products and waste water discharge from research stations.

Polystyrene microplastics-induced macrophage extracellular traps contributes to liver fibrotic injury by activating ROS/TGF-β/Smad2/3 signaling axis

Microplastics (MPs) are a type of emerging pollutant, posing a great threat to human and animal health. While recent studies have revealed the link between MPs exposure and liver injury of organisms, the effect of particle size on the level of MPs-induced hepatotoxicity and the intrinsic mechanism remain to be explored. Here, we established a mouse model exposed to two-diameter polystyrene MPs (PS-MPs, 1-10 μm or 50-100 μm) for 30 days. The in vivo results revealed that PS-MPs caused liver fibrotic injury in mice, accompanied with macrophages recruitment and macrophage extracellular traps (METs) formation, which were negatively correlated with particle size. The data in vitro showed that PS-MPs treatment could induce macrophages to release METs in a reactive oxygen species (ROS)-independent manner, and the METs formation level caused by large-size particles was higher than small-size particles. Further mechanistic analysis of a cell co-culture system revealed that PS-MPs-induced METs release led to a hepatocellular inflammatory response and epithelial-mesenchymal transition (EMT) via activating the ROS/TGF-β/Smad2/3 signaling axis, and this biological crosstalk could be relieved by DNase I. Overall, this findings demonstrates the key role of the action mechanism of METs in aggravating MPs-caused liver injury.

Microplastics pollution in mud crab (Scylla sp.) aquaculture system: First investigation and evidence

Microplastics (MPs) occurrence in farmed aquatic organisms has already been the prime priority of researchers due to the food security concerns for human consumption. A number of commercially important aquaculture systems have already been investigated for MPs pollution but the mud crab (Scylla sp.) aquaculture system has not been investigated yet even though it is a highly demanded commercial species globally. This study reported the MPs pollution in the mud crab (Scylla sp.) aquaculture system for the first time. Three different stations of the selected aquafarm were sampled for water and sediment samples and MPs particles in the samples were isolated by the gravimetric analysis (0.9% w/v NaCl solution). MP abundance was visualized under a microscope along with their size, shape, and color. A subset of the isolated MPs was analyzed by scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) for the surface and chemical characterization respectively. The average MPs concentration was 47.5 ± 11.875 particles/g in sediment and 127.92 ± 14.99 particles/100 L in the water sample. Fibrous-shaped (72.17%) and transparent-colored (59.37%) MPs were dominant in all the collected samples. However, smaller MPs (>0.05-0.5 mm) were more common in the water samples (47.69%) and the larger (>1-5 mm) MPs were in the sediment samples (47.83%). SEM analysis found cracks and roughness on the surface of the MPs and nylon, polyethylene, polypropylene, and polystyrene MPs were identified by FTIR analysis. PLI value showed hazard level I in water and level II in sediment. The existence of deleterious MPs particles in the mud crab aquaculture system was well evident. The other commercial mud crab aquafarms must therefore be thoroughly investigated in order to include farmed mud crabs as an environmentally vulnerable food security concern.

N-acetyl-L-cysteine alleviated the oxidative stress-induced inflammation and necroptosis caused by excessive NiCl2 in primary spleen lymphocytes

Introduction

Nickel (Ni) is widely used in industrial manufacturing and daily life due to its excellent physical and chemical properties. However, Ni has the potential to harm animals' immune system, and spleen is a typical immune organ. Therefore, it is crucial to understand the mechanism of NiCl2 damage to the spleen. The purpose of this study is to investigate the effects of different concentrations of NiCl2 exposure and intervening with strong antioxidants on spleen lymphocytes to better understand the damage mechanism of Ni on spleen lymphocytes.

Methods

In this experiment, mice spleen lymphocytes were used as the research object. We first measured the degree of oxidative stress, inflammation, and necroptosis caused by different NiCl2 concentrations. Subsequently, we added the powerful antioxidant N-acetyl-L-cysteine (NAC) and used hydrogen peroxide (H2O2) as the positive control in subsequent experiments.

Results

Our findings demonstrated that NiCl2 could cause spleen lymphocytes to produce a large number of reactive oxygen species (ROS), which reduced the mRNA level of antioxidant enzyme-related genes, the changes in GSH-PX, SOD, T-AOC, and MDA, the same to the mitochondrial membrane potential. ROS caused the body to produce an inflammatory response, which was manifested by tumor necrosis factor (TNF-α) in an immunofluorescence experiment, and the mRNA level of related inflammatory genes significantly increased. In the case of caspase 8 inhibition, TNF-α could cause the occurrence of necroptosis mediated by RIP1, RIP3, and MLKL. AO/EB revealed that spleen lymphocytes exposed to NiCl2 had significant necroptosis, and the mRNA and protein levels of RIP1, RIP3, and MLKL increased significantly. Moreover, the findings demonstrated that NAC acted as an antioxidant to reduce oxidative stress, inflammation, and necroptosis caused by NiCl2 exposure.

Discussion

Our findings showed that NiCl2 could cause oxidative stress, inflammation, and necroptosis in mice spleen lymphocytes, which could be mitigated in part by NAC. The study provides a point of reference for understanding the toxicological effect of NiCl2. The study suggests that NAC may be useful in reducing the toxicological effect of NiCl2 on the immune system. The research may contribute to the development of effective measures to prevent and mitigate the toxicological effects of NiCl2 on the immune system.

Microplastic occurrence and ecological risk assessment in the eight outlets of the Pearl River Estuary, a new insight into the riverine microplastic input to the northern South China Sea

Estuaries are unique transition zones connecting terrestrial and coastal environments and are recognized as primary conveyors for land-derived plastics to open oceans. Riverine microplastics (MPs) have been commonly investigated using sequential sampling which might not effectively reflect the actual load. In this study, sampling at eight outlets was performed during a complete tidal cycle to estimate the MP flux to the Pearl River Estuarine (PRE) using a concurrent sampling strategy. The MP abundances ranged from 2.90 ± 0.57-5.9 ± 2.27 particles/L. A remarkable difference between tides in MP abundances suggests tidal effect should not be overlooked in assessment. The MP load through the eight outlets was estimated at 304 trillion particles or 1102 tons into the PRE annually. Additionally, similar potential ecological risk assessment among eight rivers implied that environmental threats posed by less urbanized and populated rural areas on the western side have been under-evaluating for decades.

Distribution and risk assessment of microplastics in Liujiaxia Reservoir on the upper Yellow River

Microplastics (MPSs) distribution in global freshwater systems is extensively reported, but the distribution of MPSs in reservoirs of the Yellow River has rarely been studied. To fill in this gap, we systematically investigated the distribution of MPSs in surface water and bank sediments gleaned from Liujiaxia Reservoir of the upper Yellow River for the first time and conducted an ecological risk assessment in succession in this work. The results showed that the main polymer types of MPSs in the surface water and bank sediments of Liujiaxia Reservoir were polyethylene terephthalate (PET), polystyrene (PS), and polypropylene (PP), and the abundance of MPSs in the reservoir surface water and bank sediments ranged from 4.48 to 12.09 item/L and 447.27 to 1543.80 item/kg (dry weight), respectively. Further physical morphology analysis of MPSs in the samples revealed that MPSs in the surface water and bank sediments of Liujiaxia Reservoir were predominantly fibrous with small particle sizes (<1 mm), and there was abundant color, mainly exhibiting transparent, black, and blue. The results of the MPS pollution load index (PLI>1) and the hazard ranking of MPSs (H_Zone = 10.20 for surface water and H_Zone = 14.06 for bank sediments) yielded a hazard class II for MPS pollution in Liujiaxia Reservoir, the combined pollution risk index (PRI_Zone = 17.05 for surface water and PRI_Zone = 31.25 for bank sediments) stated clearly the potential ecological risk in the Liujiaxia Reservoir. Briefly, this study supplemented and enriched the data on the distribution of MPSs in the reservoirs of the Yellow River basin, and provide a benchmark for future pollution control and management in the reservoir area.

Occurrence of antibiotic resistance genes carried by plastic waste from mangrove wetlands of the South China Sea

Plastic waste can carry organisms such as bacterial pathogens and antibiotic resistance genes (ARGs) over long distances. However, only few studies have been conducted on the occurrence of ARGs in plastic waste from mangrove wetlands. This study evaluated the distribution characteristics and ecological risks of plastic waste from mangroves in the coastal areas of the South China Sea. The correlation between anthropogenic activity levels and abundance of ARGs in mangroves was evaluated. Transparent and white were the common colors of plastic waste in mangroves. The main shapes of plastic waste were foam and film. The predominant types of plastic waste order were as follows: polyethylene (30.18 %) > polypropylene (27.51 %) > polystyrene (23.59 %). The living area (LA) mangroves had the highest polymer hazard and pollution load indices of 329.09 and 10.03, respectively. The abundance of ARGs (5.08 × 10⁸ copies/g) on the plastic surface in LA mangroves was significantly higher than that of the other mangrove areas. Furthermore, there was a significant correlation between ARGs and intI1 on the plastic surface in mangroves. Correlation analysis between the ARGs and intI1 showed that most of the ARGs were correlated with intI1 except for msbA. In LA mangroves, sociometric and environmental factors showed significant correlations with the absolute abundances of the four ARGs and intI1, indicating that anthropogenic activities may lead to changes in the amount of ARGs on plastic surfaces. Furthermore, the ARG storage of plastic waste from different mangroves was as follows: protected areas (3.12 × 10¹⁷ copies) > living areas (2.99 × 10¹⁷ copies) > aquaculture pond areas (2.88 × 10¹⁷ copies). The higher ARG storage of LA mangroves, with the smallest area, greatly increased its ecological risk. The results of this study can provide basic data for processes that influence the distribution of plastic waste and ARGs in mangroves.

Investigation of ecological risk of microplastics in peatland areas: A case study in Vietnam

This study aims to investigate the distribution and ecological risk assessment of microplastics (MPs) in peatland areas located in Long An province, Vietnam's Mekong Delta. In general, polyvinyl chloride (60.7%), polyethylene (25.8%), and polypropylene (11.9%) were the most abundant polymers determined in the thirty sediment samples. The hazard index (HI) remarked a level of III for MPs contamination in Tan Thanh and Thanh Hoa districts. The pollution load index (PLI) and potential ecological risk index (RI) indicated that the contamination risk of MPs polymer types in the studied sites is relatively high. According to PLI values, MPs levels of peatlands in Tan Thanh and Thanh Hoa are high and moderate, respectively, while the peatland sediments in Duc Hue district are less contaminated. Furthermore, ecological risk indexes in the peatland areas were relatively high, with PLI_overall (level III); HI_overall (level V), and RI_overall (extreme danger). Hence, this study proposed a SWOT framework for challenges of MPs pollution in order to manage peatlands appropriately and minimize ecological risks. As a result, several practical strategies and appropriate approaches have been recommended to reduce microplastics towards a circular economy. These findings provide the initial quantitative assessment insights into hazard levels and ecological impacts of MPs in Vietnam's Mekong Delta peatlands.

Occurrence, distribution and risk assessment of microplastics and polycyclic aromatic hydrocarbons in East lake, Hubei, China

The pollution of microplastics (MPs) and polycyclic aromatic hydrocarbons (PAHs) in the environment is a global problem, which has attracted extensive attention of many researchers. In present study, MPs and PAHs are investigated to study the impact of human activities and their possible relationship in China's second largest urban lake, East Lake. The abundance of MPs are 3329.19 ± 2059.26 particles/m³ and 2207.56 ± 1194.04 particles/kg in water and sediment, respectively. MPs are predominantly characterized by fibers, polypropylene (PP) and polyethylene (PE), colorlessness in water and sediment. The abundance of MPs in water with frequent human activities is higher, which is reversed in sediments, indicating that disturbance is not conducive to the enrichment of MPs in sediments. The concentration of 16 PAHs are 36.95 ± 13.76 ng/L and 897.08 ± 232.34 ng/g in water and sediment, respectively. PAHs in water are mainly 2-3-ring, while there are 4-ring PAHs in sediments. The good corresponding relationship between MPs and PAHs indicates that human activities have an important impact on the distribution of pollutants compared to the interaction of pollutants. In addition, the significant positive correlation between lakeshore length and water MPs abundance indicates that surface runoff may be an important source of water MPs. The pollution load index shows that MPs in sediment has reached moderate to severe pollution level, while the water is slightly polluted level. The potential ecological risk assessment results show that more than half of the sediment sites are at dangerous to very dangerous ecological risk level.

Accumulation of Plastics and Trace Elements in the Mangrove Forests of Bima City Bay, Indonesia

Pollution with microplastics (MPs), nanoplastics (NPs) and trace elements (TEs) remains a considerable threat for mangrove biomes due to their capability to capture pollutants suspended in the water. This study investigated the abundance and composition of plastics and TEs contained in the soil and pneumatophores of Avicennia alba sampled in experimental areas (hotel, market, river mouth, port, and rural areas) differentiated in anthropopressure, located in Bima Bay, Indonesia. Polymers were extracted and analyzed with the use of a modified sediment isolation method and Fourier transform infrared spectroscopy. Trace elements were detected by inductively coupled plasma optical emission spectrometry. The lowest and highest quantities of MPs in soil were recorded in rural and hotel areas, respectively. The rural site was characterized by distinct MP composition. The amounts of sediment-trapped MPs in the tested localities should be considered as high, and the recognized polymers partly corresponded with local human activity. Concentrations of seven plastic types found in plant tissues did not entirely reflect sediment pollution with nine types, suggesting a selective accumulation (particularly of polyamides and vinylidene chloride) and substance migration from other areas. Very low concentrations of non-biogenic TEs were observed, both in sediments and pneumatophores. The results highlight the relevance of environmental contamination with plastics.

The sustainable management of microplastics pollution in sediments from China: Promulgating relevant laws and implementing targeted management

Microplastics (MPs) pollution in sediments brings a huge challenge to the sustainable development of society. China is one of the countries with the largest production and application of plastic products in the world. The sustainable management of MPs pollution in sediments from China has important implications for achieving the United Nations Sustainable Development Goals. There is a lack of targeted management measures for the sustainable management of MPs pollution in sediments from China. In this study, 74 study areas were collected to analyze the pollution status of MPs in sediments from China. The results showed that the study on MPs pollution in sediments from China was concentrated in the Bohai Rim Economic Circle (n = 12), the Yangtze River Delta Economic Circle (n = 16) and the Pearl River Delta Economic Circle (n = 13). And the average abundance of MPs in sediments from China showed a decreasing trend from coastal to inland. Fiber had the highest centrality degree in the correlation network of MPs types. The reduction of fiber in sediments can reduce the diversity of MPs in sediments from China. Population density, economic level, urbanization level and industrial structure were significantly correlated with MPs types in sediments from China. The targeted management measures can be formulated based on the contribution of different human activities to MPs types. Managing pollution sources and cutting off transmission pathways are effective means for the targeted management of MPs in sediments. In addition, legislation can effectively restrict the application of plastic products. Promulgating relevant laws and implementing targeted management are conducive to the sustainable management of MPs pollution in sediments from China. In future studies, a big data platform for MPs pollution should be established to obtain a comprehensive understanding in the pollution status of MPs in sediments from China.

Polystyrene microplastics induce autophagy and apoptosis in birds lungs via PTEN/PI3K/AKT/mTOR

Microplastics (MPs) seriously pollute and potentially threaten human health. Birds are sentinels of environmental pollutants, which respond quickly to contamination events and reveal current environmental exposure. Therefore, birds are good bioindicators for monitoring environmental pollutants. However, the mechanism of lung injury in birds and the role of the PTEN/PI3K/AKT axis are unknown. In this study, broilers treated with different polystyrene microplastics (PS-MPs) (0, 1, 10, and 100 mg/L) were exposed to drinking water for 6 weeks to analyze the effect of PS-MPs on lung injury of broilers. The results showed that with the increase of PS-MPs concentration, malonaldehyde (MDA) content increased, and catalase (CAT) and glutathione (GSH) activity decreased, further leading to oxidative stress. PS-MPs caused the PI3K/Akt/mTOR pathway to be inhibited by phosphorylation, and autophagy accelerated formation (LC3) and degradation (p62), causing autophagy. In PS-MPs exposed lung tissues, the expression of Bax/Bcl-2 and Caspase family increased, and MAPK signaling pathways (p38, ERK, and JNK) showed an increase in phosphorylation level, thus leading to cell apoptosis. Our research showed that PS-MPs could activate the antioxidant system. The antioxidant system unbalance-regulated Caspase family, and PTEN/PI3K/AKT pathways initiated apoptosis and autophagy, which in turn led to lung tissue damage in chickens. These results are of great significance to the toxicological study of PS-MPs and the protection of the ecosystem.

Polystyrene microplastics induce apoptosis in chicken testis via crosstalk between NF-κB and Nrf2 pathways

Microplastics (MPs) are a new type of pollutants that are widespread in nature, and their toxic effects on humans or animals are receiving attention. Birds are in a higher ecological niche in nature, and MPs may have potential bioaccumulation and biomagnification risks to birds. The mechanisms underlying the reproductive toxicity of MPs to birds are mainly unknown. To study the reproductive toxicity of MPs to birds, we randomly divided chickens into six groups and exposed polystyrene microplastics (PS-MPs) through drinking water (0, 1, and 100 mg/L) for 28 and 42 days. We found that PS-MPs caused testicular inflammatory infiltration and interstitial hemorrhage, resulting in testicular tissue damage; the expression of Claudin3 and Occludin in the blood-testis barrier (BTB) decreased and may damage the integrity of the BTB. PS-MPs exposure inhibited the expression of the Nrf2-Keap1 pathway, which in turn reduced HO-1 and NQO1, simultaneous GSH and T-AOC were also reduced, resulting in an imbalance of the redox system; in addition, the NF-κB signaling pathway was activated, increasing the expression of TNF-α, COX-2 and iNOS. Under redox system imbalance and inflammatory stress, exposure to PS-MPs led to decreased expression of Bcl-2 and increased Bax, cytc, caspase-8, and caspase-3, etc., activating apoptosis, and ultimately causing testicular damage. These results suggested that PS-MPs exposure led to an imbalance of the redox system and an inflammatory response, inducing both endogenous and exogenous apoptosis, resulting in testicular tissue damage. Our study provides a theoretical basis for reproductive injury mechanisms in chicken.

Effects of land use and landscape on the occurrence and distribution of microplastics in soil, China

Microplastic pollution in the soil environment has gathered widespread attention. However, little is known about the effects of land use and landscape patterns on the occurrence and distribution of microplastics in the soil. Herein, the microplastic pollution in different land uses (facility farmland, traditional farmland, orchard, grassland, and woodland) in Yuanmou County, Yunnan Province was investigated. The results showed that the abundance of microplastic ranged from 50.000 to 3450.0 items·kg^-1, with an average abundance of 595.00 ± 740.00 items·kg^-1 and a median of 375.00 items·kg^-1. Microplastics were found to primarily be green-coloured (28.4 %), fragment (72.7 %) in shape, <1 mm (75.7 %) in size, and composed of polypropylene (51.4 %). There were significant differences in the abundance and characteristics of the microplastics between different land use types. Microplastic abundance in facility farmlands, traditional farmlands, and orchard lands was significantly higher than that of grasslands and woodlands (p < 0.05). The main shape of the microplastics in facility farmlands, traditional farmlands, and orchards was fragments and it was fibers in grasslands and woodlands. The median particle size of microplastics in facility farmlands (539.50 μm) and traditional farmlands (574.00 μm), was smaller than those in the orchard (737.60 μm), grasslands (697.60 μm), and woodlands (1239.4 μm). Discrepancies among different land uses may be due to various reasons, such as different pollution sources and the weathering degree of microplastics. The results of the redundancy analysis showed that the microplastic abundance was negatively correlated with the largest patch index. It also showed that microplastic pollution was closely related to human activities. This study provides an important basis for further research on microplastic ecosystem risks that are associated with land use and provides a data basis for formulating effective prevention and control strategies and measures to mitigate soil microplastic pollution.

Pervasiveness and characteristics of microplastics in surface water and sediment of the Buriganga River, Bangladesh

Microplastics (MPs) are an emerging environmental problem due to their all-around existence and extraordinary stability. A significant number of studies are found in recent literature on the occurrence, distribution, transport, and fate of the MPs in several environmental compartments. In this study, we have investigated the occurrence and characteristics of MPs in the surface water and sediment of the Buriganga river, located beside the mega-city of Dhaka in Bangladesh. In the Buriganga river, the concentration of MPs in the surface water was found from 4.33 ± 0.58 to 43.67 ± 0.58 items L^-1, and in the sediment, MPs varied from 17.33 ± 1.53 to 133.67 ± 5.51 items kg^-1 of dry sediment. Fragment-type MPs were predominant in the surface water and sediment, which was 72.7% and 85.5% respectively. The most abundant polymer type polypropylene (PP) was found -to be 46% in the surface water and 61% in the sediment sample. The next major category, polyethylene (PE) was found to be 26% and 21%, respectively. Polystyrene (PS), polyvinyl chloride (PVC), polyethylene terephthalate (PET), and polyamide (PA) were other commonly detected polymer types. The MPs were found to be contaminated by Pb, Cd, Cr, Zn, Cu, and Sn from Energy dispersive-X-ray fluorescence (ED-XRF) analysis. Tannery-induced Cr was detected in the highest concentrations in the MPs, which were 20.67 ± 1.66 mg kg^-1 (in surface water) and 14.2 ± 1.25 mg kg^-1 (in sediment). The pollution load index (PLI) of the MPs contamination in different sampling sites along the Buriganga river was found in the risk level category of I and II. The anthropogenic influence of the city area was reflected in the PLI values, which had an increasing trend from the upstream sampling points (1.00 ± 1.00, 1.00 ± 1.00) to the downstream sites (10.09 ± 1.00, 7.71 ± 3.60).

The fate of microplastics in estuary: A quantitative simulation approach

Microplastics pollution is an emerging environmental concern. However, there are almost no MPs numerical simulation studies in the Yangtze Estuary which is considered as the largest plastic export in the world and quantitative simulation is not carried out in the existing models. Therefore, completing quantitative simulation and exploring different patterns of MPs transport are the main objectives of this study. In addition, the concentration distribution and risk of MPs are also analyzed. Mass-Number method is proposed to quantitatively simulate microplastics concentration in Feb. and May with errors of less than 18%. Compared with sediment flocculation and settling transport, independent floating transport is more susceptible to surface currents resulting in increased beaching and more inhomogeneous concentration distribution. Meanwhile, under the influence of current, local topography and salt wedge, the MPs perform linear motion and clockwise spiral motion inside and outside the estuary and rapidly form a "hot spot" on the southeastern part of Chongming Island and 57% to 90% of MPs are beached or settled inside the estuary, especially on the north shore. Therefore, MPs risk in some sensitive targets should be concerned according to risk assessment results. Our results break the space-time limit and explore the fate of MPs in the Yangtze Estuary and provide new idea and concern of MPs numerical simulation.

Towards circular economy: Sustainable soil additives from natural waste fibres to improve water retention and soil fertility

Human activity is accompanied by the introduction of excessive amounts of artificial materials, including geosynthetics, into the environment, causing global environmental pollution. Moreover, climate change continues to negatively affect global water resources. With the intensification of environmental problems, material reusability and water consumption limitations have been proposed. This study replaced synthetic soil additives with biodegradable materials and analysed the potential and sustainable processing of natural fibrous materials, which form problematic waste. Waste fibres are the basis of innovative soil water storage technologies in the form of biodegradable and water-absorbing geocomposites (BioWAG). We analysed the influence of BioWAGs on plant vegetation and the environment through a three-year field experiment. Furthermore, biomass increases, drought effect reductions, and biodegradation mechanisms were analysed. Natural waste fibres had a positive influence, as they released easily accessible nutrients into the soil during biodegradation. BioWAGs had a positive influence on the biometric parameters of grass, increasing biomass growth by 430 %. Our results indicated that this is an effective method of waste fibre management that offers the possibility to manufacture innovative, environmentally friendly materials in compliance with the objectives of circular economy and the expectations of users.

Endoplasmic reticulum stress-controlled autophagic pathway promotes polystyrene microplastics-induced myocardial dysplasia in birds

In complex ecosystems, birds are generally long-lived and occupy high trophic positions, making them good bioindicators for monitoring environmental contaminants. The effects of microplastics (MPs) on myocardial development in bird is currently unknown. Chicks, as a high trophic level terrestrial bird, may be more affected by MPs exposure and. Therefore, we established an in vivo model of chicks exposed to different concentrations of polystyrene microplastics (PS-MPs) and selected 12-day-old chicken embryos in vitro to extract primary cardiomyocytes to further investigate the potential molecular mechanisms of the effect of PS-MPs on myocardial development in birds. Histopathological observations revealed that the PS-MPs treated exhibited loose and irregular myocardial arrangement, large cell gaps and broken myocardial fiber bundles. More mechanistically, TnnT2, Nkx2-5, Gata4, TBX5 and ACTN2 were down-regulated, endoplasmic reticulum (ER) stress markers GRP78, PERK, eIF2α, IRE1, ATF4, ATF6 and CHOP were overexpressed, autophagy-related genes LC3, ATG5, Beclin1 and P62 were down-expressed after PS-MPs exposure, and the addition of 4PBA effectively deregulated the above aberrant expression. Hence, our report indicated that PS-MPs induced myocardial dysplasia in birds is mainly attributed to the ER stress-mediated autophagic pathway. This provided data supporting the protection of birds from the health risks of MPs pollution. More critically, the study of cardiac developmental toxicity in birds may help to better explain or solve the problem of MPs pollution in complex ecosystems.

Polystyrene microplastics-induced cardiotoxicity in chickens via the ROS-driven NF-κB-NLRP3-GSDMD and AMPK-PGC-1α axes

Microplastics (MPs) pollution is getting increasingly prominent, and its dangers have attracted widespread attention. The heart is the central hub of the organism's survival, and the mechanism of MPs-induced heart injury in chickens is unknown. Here, we investigated the effects of 5 μm polystyrene microplastics (PS-MPs) on the heart and primary cardiomyocytes of chickens at varied concentrations. We observed that PS-MPs caused severe pathological damage and ultrastructural changes in heart, induced myocardial pyroptosis, inflammatory cell infiltration and mitochondrial lesions. PS-MPs evoked abnormal antioxidant enzyme content and ROS overproduction. Detailed mechanistic investigation indicated that PS-MPs triggered pyroptosis via NF-κB-NLRP3-GSDMD axis and exacerbated myocardial inflammation (NLRP3, Caspase-1, IL-1β, IL-18, ASC, GSDMD, NF-κB, COX-2, iNOS and IL-6 overexpression). Additionally, PS-MPs induced mitochondrial damage (TFAM, OPA1, MFN1 and MFN2 down-expression, DRP1 and Fis1 overexpression) and energy metabolism disorders (HK2, PKM2, PDHX and LDH up-regulation) by inhibiting AMPK-PGC-1α pathway. Interestingly, NAC alleviated these aberrant manifestations in vitro. We suggested that PS-MPs driven alterations in NF-κB-NLRP3-GSDMD and AMPK-PGC-1α pathways via ROS overload, which in turn triggered oxidative stress, myocardial pyroptosis, inflammation, mitochondrial and energy metabolism dysfunction. This provided theoretical bases for protecting chickens from toxic injury by MPs.

A case study of distribution and characteristics of microplastics in surface water and sediments of the seas around Shenzhen, southern coastal area of China

Microplastics (MPs), known to cause environmental pollution, is attracting a growing attention worldwide owing to their extensive existence and potential risks to biota. The marginal sea areas are suspected to be especially susceptible to MPs pollution. Unfortunately, data on MPs in the surface water and sediments ecosystems are still limited, particularly in the southern coastal areas of China. The study was successfully utilized to explore the distribution and characteristics of MPs below 5 mm collected from 14 sites in the seas around Shenzhen, a typical special economic zone of China. MPs were detected in both surface water and sediments with concentrations ranging from 3.8 to 7.8 items per liter and 2.6 × 10³ to 10.0 × 10³ items per kilogram, respectively. The highest abundance of MPs appeared in S5/S9 and S14 in surface water and sediments, respectively. Fiber and film with small particle size (<0.5 mm) were identified as typical and abundant MPs type among all samples. In addition, polyethylene (PE) was considered as dominant forms of MPs in surface water and sediment samples. Results from this study indicated a positive correlation with abundance of MPs and urbanization rate, which also showed an evident difference of MPs in different urban functional areas. Based on the types and quantity of detected MPs, we assessed the risk of MPs pollution in this study area, and the ecological risk category of MPs was at a high level. Importantly, our work might be employed as a potential information so as to better understand MPs pollution, source tracing and ecological risk assessment, which enhances the possibility of achieving effective control and supervision of MPs pollution in southern coastal aera of China.

Oxidative stress mediated by the TLR4/NOX2 signalling axis is involved in polystyrene microplastic-induced uterine fibrosis in mice

Microplastics (MPs), as a new environmental pollutant, have received widespread attention worldwide. Uterine fibrosis is one of the main factors of female reproductive disorders. However, it is unclear whether the female reproductive disorders caused by MPs are related to uterine fibrosis. Therefore, in this study, we constructed female mouse models exposed to polystyrene microplastics (PS-MPs). We found that PS-MP exposure resulted in endometrial thinning and severe collagen fibre deposition in female mice. Further mechanistic studies found that PS-MP exposure increased the expression of high mobility group Box 1 (HMGB1) and acetyl-HMGB1, further activating the Toll-like receptor 4/NADPH oxidase 2 (TLR4/NOX2) signalling axis and eventually causing oxidative stress. Afterwards, oxidative stress elicited the activation of Notch and the transforming growth factor β (TGF-β) signalling pathway, leading to increased levels of fibrotic proteins and collagen. Correspondingly, PS-MP treatment upregulated the expression of TLR4 and NOX2 and the level of reactive oxygen species (ROS) and increased the levels of fibrotic protein and collagen in mouse endometrial epithelial cells cultured in vitro. Conversely, inhibition of the TLR4/NOX2 signalling pathway effectively reduced the level of ROS in cells, weakened the upregulation of Notch and TGF-β signalling by PS-MPs, and efficiently reduced the expression of fibrotic and collagen genes. In summary, we demonstrated a new mechanism by which MPs induce uterine fibrosis in mice, that is, by inducing oxidative stress to activate the Notch and TGF-β signalling pathways by triggering the TLR4/NOX2 signalling axis. Targeting TLR4/NOX2 signalling may consequently prove to be an innovative therapeutic option that is effective in alleviating the reproductive toxicity of PS-MPs. Our study sheds new light on the reproductive toxicity of MPs and provides suggestions and references for comparative medicine and clinical medicine.

Di-(2-Ethylhexyl) Phthalate and Microplastics Induced Neuronal Apoptosis through the PI3K/AKT Pathway and Mitochondrial Dysfunction

Di-(2-Ethylhexyl) phthalate (DEHP) and microplastics (MPs) have released widespread residues to the environment and possess the ability to cause damage to humans and animals. However, there are still gaps in the study of damage to neurons caused by DEHP and MPs in mice cerebra and whether they have combined toxic effects. To investigate the underlying mechanism of action, mice were fed 200 mg/kg DEHP and 10 mg/L MPs in vivo. In vitro, NS20Y (CBNumber: CB15474825) cells were treated with 25 μM DEHP and 775 mg/L MPs. Next, qRT-PCR and western blot analysis were performed to evaluate PI3K/AKT pathway genes, mitochondrial dynamics-related genes, apoptosis-related genes, and GSK-3β and its associated genes, mRNA, and protein expression. To determine pathological changes in the mice cerebra, hematoxylin and eosin (H&E) staining, transmission electron microscopy, and TUNEL staining were employed. To determine the levels of reactive oxygen species (ROS) and apoptosis cells in vitro, ROS staining, acridine orange/ethidium bromide (AO/EB) staining, and flow cytometry were performed. Our results demonstrated that DEHP and MPs caused changes in mitochondrial function, and GSK-3β and its associated gene expression in mice through the PI3K/AKT pathway, which eventually led to apoptosis of neurons. Moreover, our findings showed that DEHP and MPs have a combined toxic effect on mice cerebra. Our findings facilitate the understanding of the neurotoxic effects of DEHP and MPs on neurons in the cerebra of mice and help identify the important role of maintaining normal mitochondrial function in protecting cerebrum health.