Microplastics In Surface Water Research Articles

Microplastic pollution characteristics and ecological risk assessment in the Wuding River Basin, China

Microplastics (MPs), as a new type of environmental pollutant, have attracted extensive attention in recent years. However, there has been relatively little research specifically focusing on MPs in the Yellow River Basin, China, particularly regarding MP migration patterns. Based on surface water and sediment samples from 19 sampling sites in the Wuding River (WDR), the abundances and characteristic distributions of MPs were analyzed, and the environmental factors affecting their distribution and potential ecological risks were evaluated. The results showed that the MP abundances in surface water and sediments of the WDR were significantly different (P <0.05), with mean values of 2.98 ± 0.69 items/L and 419.47 ± 75.61 items/kg, respectively. In terms of MP characteristics, the most common size class was 0.1-0.5 mm in surface water. Polyethylene (PE, 32.50%) and polypropylene (PP, 27.50%) were the main polymer types of MPs in surface water. Although similar MP characteristics were observed in sediments, there were significantly more particles in the <0.1 mm particle size (P <0.05), which was 15.0% higher than in surface water. Also, more high-density MP fragments were observed in sediment samples. The retention of MPs in sediments was influenced by the MP characteristics (density, shape, particle size) and sediment particle size. In contrast, the MP abundance in surface water was more closely related to the presence of other environmental pollutants, such as total phosphorus (WTP) and ammonia nitrogen (WAN). Temperature (T), agricultural land (AGR), and residential land (RES) only had significant effects on the distribution of MPs in surface water (P <0.05). Potential ecological risk assessments revealed that MP pollution in sediments was more serious than in surface water, especially in the middle and lower reaches. The results of this study are important for understanding MP transport in a sandy river and for eliminating potential sources of MPs.

Significant regional disparities in riverine microplastics

Research on riverine microplastics has gradually increased, highlighting an area for further exploration: the lack of extensive, large-scale regional variations analysis due to methodological and spatiotemporal limitations. Herein, we constructed and applied a comprehensive framework for synthesizing and analyzing literature data on riverine microplastics to enable comparative research on the regional variations on a large scale. Research results showed that in 76 rivers primarily located in Asia, Europe, and North America, the microplastic abundance of surface water in Asian rivers was three times higher than that in Euro-America rivers, while sediment in Euro-American rivers was five times more microplastics than Asia rivers, indicating significant regional variations (p < 0.001). Additionally, based on the income levels of countries, rivers in lower-middle and upper-middle income countries had significantly (p < 0.001) higher abundance of microplastics in surface water compared to high-income countries, while the opposite was true for sediment. This phenomenon was preliminarily attributed to varying levels of urbanization across countries. Our proposed framework for synthesizing and analyzing microplastic literature data provides a holistic understanding of microplastic disparities in the environment, and can facilitate broader discussions on management and mitigation strategies.

Secondary risks induced by polyethylene microplastics during the disinfection processes of chlorination, UV irradiation, and ozone treatment

ABSTRACT The presence of microplastics in surface waters poses potential hazards to both organisms and human health. Traditional water treatment processes have proven to be inadequate in effectively removing microplastics. Besides, previous studies have often utilized disinfectant dosages that surpass those commonly employed in drinking water treatment plants (DWTPs), and the biotoxicity changes induced by microplastics after disinfection remain largely unexplored. To address these knowledge gaps, our study aimed to investigate the impact of practical disinfectant dosages on the leaching of organic compounds from microplastics and the formation of disinfection byproducts (DBPs). Furthermore, the resulting acute and genetic toxicity was evaluated through bioassays. Our findings revealed an elevated release of dissolved organic matter (DOM) derived from microplastics. Additionally, both acute and genetic toxicity increased following various disinfection processes. Specifically, chlorination exhibited the highest level of toxicity in short-term disinfection, while the pretreatment of ozonation followed by residual chlorination demonstrated the highest toxicity in the long-term disinfection, which was correlated with the concentration of CHCl3 formed. These findings will advance our understanding of the potential risks associated with microplastics during various disinfection processes, with the ultimate goal of safeguarding water supplies.

Influence of ongoing discharge from multiple wastewater treatment plants on microplastic patterns in small-scale receiving rivers

As widely acknowledged, wastewater treatment plants (WWTPs) stand as significant contributors to the presence of microplastics in surface water. Nonetheless, there exists a notable research gap regarding the extent of potential pollution resulting from the concurrent and uninterrupted discharges originating from multiple WWTPs into small-scale receiving water bodies. This study endeavors to address this knowledge deficit by conducting a thorough investigation into the prevalence of microplastics in surface water. The research encompasses seven distinct locations within the Changzhou section of the Beijing-Hangzhou Grand Canal and the effluent of three WWTPs situated along the tributary. The results indicate differences in the distribution of microplastics in surface waters of mainstream and tributaries. While the microplastic abundance and composition showed little variation along the main stream, the tributaries displayed an overall increasing trend in microplastic abundance from upstream to downstream. Notably, the major contributors to this increase were fragments, fiber particles, and microplastics with particle sizes ranging from 100 to 300 μm. Considering that the primary distinction between the tributaries and the mainstream is the presence of the three WWTPs along the tributaries, the study conducted a correlation analysis between river surface water and effluents from these plants. The results indicated a stronger correlation between the tributaries and the effluents, suggesting that WWTPs are one of the primary factors contributing to the elevated levels of microplastics in the tributaries. Finally, a comparative analysis of microplastic abundance in the Beijing-Hangzhou Grand Canal's Changzhou section and other regions was conducted. The findings revealed that the microplastic pollution level in the Beijing-Hangzhou Grand Canal's Changzhou section is higher than that in most other rivers. Therefore, the issue of microplastic pollution in the Beijing-Hangzhou Grand Canal's Changzhou section warrants our attention, particularly with regard to the effectiveness of microplastic removal by the WWTPs along its course.

Abundance of microplastics in surface water of tropical reservoirs during contrasted season, the case of Dau Tieng and Tri An, Vietnam

Abundance of microplastics in surface water of tropical reservoirs during contrasted season, the case of Dau Tieng and Tri An, Vietnam

Microplastic contamination in rivers: a survey from the Nan River, Thailand

BackgroundSince the 1970s, microplastic contamination has been discovered in various environments. These emerging pollutants threaten water quality and freshwater ecosystems. We aimed to assess microplastic contamination in the Nan River by quantifying their presence, characterising their morphology, and identifying their polymer composition. MethodsThe survey was conducted along the Nan River in northern Thailand, which is divided into three distinct zones based on land use (ie, community areas, agricultural areas, and natural areas). A wide array of samples, including surface water, sediment, and specimens from five aquatic species—Barbonymus altus, Laides hexanema, Kryptopterus cryptopterus, Pomacea canaliculata, and Pseudodon cambodjensis cambodjensis—were collected. The presence of microplastics was analysed via the wet peroxide oxidation process for sample digestion, morphological characteristics were assessed through microscopic examination, and Fourier transform infrared spectrophotometry was used to identify the polymer composition of the microplastics. FindingsNatural areas had the highest mean concentration of microplastics in surface water (23·67 pcs/L, SD 14·22), whereas community areas had the highest mean concentration in soil sediment (24·67 pcs/g, 15·04). No statistically significant differences in the amounts of microplastics were observed among the various land-use zones. Microplastics were predominantly found in the gastrointestinal tracts of fish specimens, with varying quantities observed among different aquatic species; B altus had the highest concentration (11·80 pcs/g, 8·98). The primary microplastic shapes identified were filaments (53·99%), fragments (35·58%), and cylindrical forms (10·43%). We identified ten different polymer types, with polypropylene, nylons, and polymethyl methacrylate being the most prevalent among them. InterpretationAnalysing microplastic pollution in this area brings attention to the issues affecting the rivers of Thailand and emphasises ecological risks, particularly microplastic presence in aquatic species. Because of the Nan River's ecological importance, we call for increased research and collaboration to address the increasing threat of microplastic pollution. FundingNaresuan University.

Morphological and Chemical Characteristics of Microplastics in Surface Water of the Vaal River, South Africa

Microplastics research in South Africa has focused on marine and coastal areas, with limited studies reporting microplastics in freshwaters. To address this gap, we conducted this study to investigate the presence, abundance, physical characteristics, and chemical composition of microplastics in the surface water of the Vaal River, one of the most important freshwater systems in South Africa. Twenty-two surface water samples were collected along 60 km of the middle part of the river using a 55 μm plankton net. Samples were treated by acid digestion, and MPs were separated by density separation. Physical identification was performed using a Nikon stereomicroscope, and chemical composition was identified using Raman spectroscopy. MPs were observed in all samples with 0.13 to 2.52 particles/m3 concentrations. Microplastics ranged in size from 0.06 – 4.95 mm, with more than 89% less than 2 mm, and 81% were fragments (39%) and fibers (42%). Microplastics were observed in numerous colours, of which green, black, and blue were the most dominant, representing 22%, 19%, and 18%, respectively. Chemical analysis revealed the polymer types as high-density polyethylene (HDPE), polypropylene (PP), and low-density polyethylene (LDPE). In addition, two colourants, pigment yellow 83 and carbon black, were detected. This study provides new data on microplastic occurrence and characteristics in the Vaal River system and offers a baseline for future monitoring. Our findings confirm that the Vaal River is under a real threat of microplastic contamination, which could impact its role as a significant freshwater system in South Africa.Highlights• Microplastics were prevalent in the surface water of the Vaal River.• Fibrous, small-sized, and coloured microplastics were most abundant.• Polymers were identified as HDPE, LDPE, and PP.

A Multicompartment Assessment of Microplastic Contamination in Semi-remote Boreal Lakes.

Microplastic contamination is ubiquitous across the globe, even in remote locations. Still, the sources and pathways of microplastics to such locations are largely unknown. To investigate microplastic contamination in a semi-remote location, we measured microplastic concentrations in nine oligotrophic lakes within and around the International Institute for Sustainable Development-Experimental Lakes Area in northwestern Ontario, Canada. Our first objective was to establish ambient concentrations of microplastics in bottom sediments, surface water, and atmospheric deposition in semi-remote boreal lakes. Across all lakes, mean shallow and deep sediment microplastic concentrations, near-surface water microplastic concentrations from in situ filtering, and dry atmospheric microplastic deposition rates were 551 ± 354 particles kg-1, 177 ± 103 particles kg-1, 0.2 ± 0.3 particles L-1, and 0.4 ± 0.2 particles m-2 day-1, respectively. Our second objective was to investigate whether microplastic contamination of these lakes is driven by point sources including local runoff and direct anthropogenic inputs or nonpoint sources such as atmospheric deposition. Lakes were selected based on three levels of anthropogenic activity-low, medium, and high-though activity levels were minimal across all study lakes compared with highly populated areas. Whereas a positive correlation would indicate that point sources were a likely pathway, we observed no relationship between the level of anthropogenic activity and microplastic contamination of surface water. Moreover, the composition of microplastics in surface water and atmospheric deposition were similar, comprising mostly polyester and acrylic fibers. Together, these results suggest that atmospheric deposition may be the main pathway of microplastics to these remote boreal lakes. Environ Toxicol Chem 2024;43:999-1011. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

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.

Identification and quantification of microplastics in surface water of a southwestern Mediterranean Bay (Al Hoceima, Morocco)

In this study, we evaluated the pollution in Al Hoceima Bay (Southwestern Mediterranean, Morocco) by microplastics. Nine stations were investigated in 2019, 2020, and 2021, using the Manta net and the microplastics were identified and quantified with Raman Spectroscopy. The obtained results showed that fibers, fragments, pellets, and films were the predominant types of microplastics. The dominant size of microplastics ranged from 0.15 to5 mm while 0.3–0.5 mm was the most prevalent with 46.97 %. Seven colours counting white and blue as dominant items were recorded. The abundance of microplastics was 1–15 items/m3, with an average of 4.70 ± 4.50 items/m3. Four polymers dominated by Polyethylene (67.4 %), Polypropylene (23.2 %), Polystyrene (7.1 %), and Polyethylene Terephthalates (2.3 %) were identified. The spatial distribution of microplastics was variable. The abundance of microplastics was not related to the distance separating potential sources from the sampled stations. Our study provided the initial data on microplastics and their distribution along the Mediterranean coasts of Morocco, recommended for future investigations of marine pollution in the Mediterranean basin.

Microplastics in Qinghai-Tibet Plateau and Yunnan-Guizhou Plateau lakes, China

As an emerging environmental pollutant, microplastics (MPs) have received widespread attention. Recently, studies examining microplastic pollution in plateau lakes have been increasing, but few have examined the distributions, sources, and fates of MPs in different plateau areas. In this work, the abundances and characteristics of MPs in surface waters and sediments in lakes of the Qinghai-Tibet Plateau (QTP) and Yunnan-Guizhou Plateau (YGP) were systematically investigated. The abundances of MPs in the lakes of the QTP ranges within 0.05–1.8 n/L in surface waters and 10–2643.7 n/kg in sediments. In the lakes of the YGP, the abundances of MPs ranged within 1.3–10.1 n/L in surface waters and 171.7–4260 n/kg in sediments. The dominant shape, color, and size class of MPs were fiber, transparent, and 0–0.5 mm in plateau lakes, respectively. MPs were mainly composed of polypropylene, polyethylene, and polyethylene terephthalate polymers. The different sources of MPs in the QTP and YGP lakes were mainly due to differences in human activities. The primary sources of microplastic pollution in the lakes of the QTP were tourism and atmospheric transport, while sewage discharge, agriculture, and fishing activities were the main sources of MPs in urban lakes of the YGP. Although the level of microplastic pollution in plateau lakes was relatively low, the sources should be identified and monitored so that the effects and extent of microplastic pollution in these fragile environments can be fully understood. This study provides a valuable dataset and theoretical basis for subsequent research on microplastic pollution in plateau lakes.

Spatial and temporal distribution characteristics of microplastics in surface water of typical shallow lake in the middle and lower reaches of Yangtze River: A case study of Lake Baoan, Hubei Province

Spatial and temporal distribution characteristics of microplastics in surface water of typical shallow lake in the middle and lower reaches of Yangtze River: A case study of Lake Baoan, Hubei Province

Image processing techniques for measuring primary microplastic abundance in various of dispersant

Microplastics have become one of the world’s most important environmental issues and have received widespread attention as a new type of pollutant. Microplastic quantification methods have evolved from manual to semi-automated and automated methods. These methods still possess drawbacks such costly detecting equipment, lengthy detection durations, and imprecise detection rates, making the detection of microplastics difficult in natural environments. This study aimed to measure the abundance of primary microplastics (microbeads) using Image Processing Techniques (IPT) with various dispersants and validated them using microscopy. Plugable Digital Viewer v.3.1.07 software was used to capture digital images of the IPT tool, while the microscope used Obtilab viewer 3.0. The IPT results were processed and analyzed using ImageJ 1.53t software. The originality of this study is that digital images were taken directly in liquid samples with the preparation sample dispersant so that microplastics in surface water could be directly quantified and identified. This study provides a very strong correlation between the sample mass and particle counting, as seen from R2&gt;0.75. A statistical test of the data obtained (P-Value&gt;0.05) demonstrated a normal distribution of the data. The t-test results between each mass variation obtained (P-Value &lt;0.05) indicated that the microplastic particles from each mass variation were different. The LoD for PP and PE were 1.75 and 0.00009 respectively while the LoQ were 28.5 and 39.5. The %recovery from 10 repetitions produced consistent values for PP and PE, which had less stable values obtained at 0% in repetitions 1.5 and 8. The %RSD from 10 repetitions was below 40%.

Occurrence and Distribution Characteristics of Microplastics in Surface Water of China: a Review

Occurrence and Distribution Characteristics of Microplastics in Surface Water of China: a Review

Detection of microplastics particles in the aquatic environment by staining

Introduction. Microplastics are among the most common environmental contaminants worldwide, which levels of pollution and harm to health have begun to be assessed only recently. Biological activity of microplastics has been established in "in vivo" and "in vitro": studies: they were found to impair the development and functioning of the digestive, reproductive, central nervous, immune, and circulatory systems, induce tissue and organ dysplasia, be geno-, neuro-, and cytotoxic. The findings necessitate monitoring of microplastics in water by supervisory authorities and business entities. Yet, there is no official method for determining microplastics in the aqueous environment in the Russian Federation.&#x0D; Our objective was to apply an express method for the qualitative determination of microplastics in surface waters and treated water before supply.&#x0D; Materials and methods. We analyzed water samples taken from two regional reservoirs and at water treatment plants before supply to the centralized system in two industrial cities of the Sverdlovsk Region by Nile red staining and subsequent identification of microplastics using a phase-contrast fluorescence microscope.&#x0D; Results. We found microplastics in both surface and treated water samples, and established their shape and size.&#x0D; Limitations. This method evaluates only qualitative characteristics of microplastics without establishing their chemical composition; the resolution of a microscope determines analytical accuracy.&#x0D; Conclusions. The applied method has enabled us to find microplastics in surface waters sampled at different depths and in the treated water before supply. Round and rod-shaped particles were observed in both types of water while those in the form of elongated filaments were detected only in surface water samples.

Microplastic particles in river sediments and water of southwestern Nigeria: insights on the occurrence, seasonal distribution, composition, and source apportionment.

Microplastics (MPs) are globally recognized as an emerging environmental threat, particularly in the aquatic environment. This study presents baseline data on the occurrence and distribution of MPs in sediments and surface water of major rivers in southwestern Nigeria. Microplastics were extracted by density separation and polymer identification using Fourier transformed infrared spectroscopy in attenuated total reflectance mode (FTIR-ATR). The abundance of MPs in surface sediment and water samples across all locations ranged from 12.82 to 22.90 particle/kg dw and 6.71 to 17.12 particle/L during the dry season and 5.69 to 14.38 particle/kg dw and 12.41 to 22.73 particle/L during the wet season, respectively. On average, fiber constituted the highest percentage of MP in sediments (71%) and water (67%) while foam accounted for the lowest values of 0.6% and 1.7%, respectively. Polypropylene(PP) and polyethylene (PE) were the main MPs across all locations based on Fourier transform infrared spectroscopy (FTIR). MPs of size < 1mm were the most abundant (≥ 55%) on average in both water and sediments. The study identified run-off from human activities and industrial wastewater as potential sources of MP exposure based on positive matrix factorization. The study suggests assessing the impact of different land-use activities on MPs occurrence and distribution in addition to quantifying MPs in seafood as a way forward in food safety management systems for further studies. This study confirmed the occurrence and widespread distribution of MPs in surface water and sediments and provides a database on MP pollution in Nigeria.

Microplastic pollution in urban rivers within China's Danxia landforms: Spatial distribution characteristics, migration, and risk assessment

The potential deleterious effects of microplastics on environmental integrity and human health have elicited global attention. Particularly vulnerable to microplastics are Danxia landforms, characterized by their unique topographical features and ecologically fragile milieu. Notwithstanding, empirical studies assessing the prevalence of microplastics in these unique landforms remain strikingly limited. The present investigation comprehensively examined the abundance of microplastics in surface water, sediment, and groundwater across six cities and six counties within the Danxia landforms. Comparative analysis revealed a moderate level of microplastic contamination in the urban rivers of the Danxia region relative to other freshwater rivers. Anthropogenic activities, notably urban wastewater treatment and tourism, emerged as principal contributors to microplastic pollution. Sedimentary microplastics exhibited an accumulative trend from upstream to downstream locations. The risk assessment revealed a high potential ecological risk in counties and a moderate risk in cities. Cluster analysis suggested that groundwater microplastics were a confluence of hydraulic interactions between surface and subsurface waters within the Danxia region. This investigation elucidates the microplastic contamination profile, origins, migratory patterns, and associated risks in Danxia's urban rivers, thereby furnishing scientific underpinning for health and ecological preservation strategies within urbanized Danxia landscapes.

Characterization and risk assessment of microplastics in laver from the Yueqing Bay

Microplastics (MPs) pollution is regarded as a global challenge for ocean. As an important food source of human, macroalgae could suffer MP pollution and transmit MPs into human via food web. However, few studies have revealed the relationship of MP pollution between macroalgae and its habitat. In order to evaluate the trapping and accumulation of MPs in macroalgae and surface water, the present study investigated MP pollution in a typical aquaculture macroalgae species, laver (Porphyra haitanensis) in the Yueqing Bay. The results indicated MP abundance in laver (1.45 ± 0.26 items/g) was at a medium level while MP abundance in surface water (0.21 ± 0.15 item/m3) was at a relatively low level worldwide. Distribution trend and characteristics of MPs in laver and surface water showed highly similarity. Besides, heavy metal elements (Fe and Zr) were detected on the surface of MPs trapped by laver. Pollution load index (PLI) in surface water of the whole bay was low, indicating MP pollution was not serious in the Yueqing Bay. Due to the discharging of domestic sewage in recent years, fiber-shaped, textile MPs accounted for most in laver and surface water of the Yueqing Bay. These results indicated that MPs in surface water could be trapped by P. haitanensis, thus macroalgae cultivation might be a potential way to alleviate seawater MP pollution in the nearshore areas.

Temporal and spatial variation of microplastics in the urban rivers of Harbin

This study was to investigate temporal and spatial variation of microplastics in surface water and sediment in the urban rivers of Harbin during dry and wet season. Water samples (n = 25) in Xinyi River (n = 13) and Ashe River (n = 12) were collected from the selected sampling points. Microplastics in urban rivers in Harbin included polyethylene (PE), polypropylene (PP), polystyrene (PS), polyamide (PA), polyvinyl chloride (PVC) and polyethylene terephthalate (PET). The results show that urban rivers in Harbin had relatively mild microplastic abundance with most fragments in shape and colorless in color. PP and PE were the major polymers in surface water samples, while PVC and PET were the major polymers in sediment, which were dominated by large-size and granulate shape microplastics. Source apportionment demonstrate that the main sources of microplastics in Xinyi River and Ashe River during dry season were domestic wastewater and effluent from rainfall, while the main sources of microplastics in Xinyi River and Ashe River during wet season were wastewater, atmospheric sedimentation, and agricultural source. The morphology of microplastics in surface water and sediment in urban rivers of Harbin was negatively correlated with water velocity and positively correlated with the concentration of suspended matter, dissolved oxygen, and conductivity. Riparian vegetation on the sides of Xinyi and Ashe River decreased migration process of microplastics by vegetal purification and then resulted in low abundance of microplastics. In conclusion, this study highlighted the occurrence characteristics, source apportionment and environmental influencing factors of microplastics in urban rivers of Harbin, which may develop new insights into the reduction of abundance of microplastics in the urban rivers.

Seasonal variations of microplastics in surface water and sediment in an inland river drinking water source in southern China

The aim of this study was to examine microplastic (size distribution of 0.05–5 mm) occurrence and distribution in drinking water source of XJ River during both flooding and dry periods. Surface water and sediment samples were collected from the CS City section of the river in August and December 2020. During the flooding period, microplastic abundances were observed at 0.72–18.6 (7.32 ± 2.36) items L−1 in surface water and 26.3–302 (150 ± 75.6) items kg−1 dry weight (dw) in sediment. In the dry period, abundances were slightly higher at 2.88–17.7 (11.0 ± 3.08) items L−1 and 27.0–651 (249 ± 182) items kg−1 dw, respectively. Microplastics were found in higher concentrations in urban areas and downstream of wastewater treatment plants, suggesting anthropogenic sources. The diversity in shapes, colors, and types of microplastics in surface waters and sediments indicates specialized enrichment processes and persistent sources of microplastic pollution. Approximately 60 % of the microplastic particles identified fall within the 50–100 μm range. Furthermore, a significant correlation was observed between these smaller-sized particles and the overall prevalence of microplastics. Fourier-transform infrared spectroscopy and scanning electron microscopy indicated that the microplastics had been subjected to weathering in the environment, contributing to the production of oxygen-containing functional groups and surface cleavage features. The utilization of energy dispersive spectroscopy revealed the presence of microplastics associated with various heavy metals, highlighting the intricate nature of microplastic pollution. Moreover, the high abundance of microplastics may pose a potential ecological risk to the aquatic environment of the XJ River. The results of this study demonstrate concerning levels of microplastics in the XJ River, despite its status as a high-quality water source.