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

The pollution of microplastics in sediments of the Yangtze River Basin: Occurrence, distribution characteristics, and basin-scale multilevel ecological risk assessment.

Characteristics of soil microplastics and ecological risks in the Qilian Mountains region, Northeast Tibetan Plateau

Abundance, characteristics, and ecological risks of microplastics in the riverbed sediments around Dhaka city

Estuarine habitats are a critical zone of the Earth with strong land-sea interactions, that are strongly influenced by human activities. Microplastics (MPs) pollution in the Yellow River Delta (YRD) wetland, a typical young warm-temperate estuarine wetland, has not been comprehensively studied. The morphology, abundance, particle size, and polymer composition of MPs in the surface sediments of the YRD wetland were determined, and the pollution status and ecological risk in the study area were evaluated using the pollution load index (PLI) and potential pollution risk index (PRI). The results showed that the abundance of MPs in the YRD wetland was 20-520 n·kg-1, with a median value of 150 n·kg-1. The MPs were primarily fibers in shape and black in color, with particle size over 1 mm. The polymer components were primarily rayon, polyethylene, polyester, and polyethylene terephthalate. The PLI and PRI values of the MPs in the area were between 0.04-0.96 and 0.00-171.60, respectively, indicating that the pollution of MPs in the YRD wetland was at a slightly polluted level with low ecological risk.

The reduction of renewable freshwater and the increased variety of water pollutants have made governments establish well-documented monitoring programs to maintain the quality of water resources. The Jajroud river, as a primary source of surface water, has supplied 30% of the drinking water of Tehran for more than 55 years. The present study aimed to calculate the water quality index (WQI), determine the abundance of microplastics (MPs) pollution and evaluate the induced-ecological risk. Seven samples of water and four samples of wastewater sources from the Jajroud River were collected three times. The physicochemical and microbial properties, the abundance of MPs, and the type of polymer in this river were determined using standard procedures. The WQI ​​exceeded 76.1 in all sampling points, indicating that the water had of good quality. Ammonia was the main factor involved in the reduction of the WQI. The average abundance of MPs in water and wastewater samples was 12.14 ± 10.07 and 30.62 ± 9.33 particles. L-1, respectively. The fibers (70.96%) and 1–2.5 mm (30.25%) were the dominant shape and size of MPs in water, while fibers (73.05%) with sizes smaller than 0.2 mm (29%) were predominate for MPs in wastewater samples. The dominant polymers were polystyrene (PS) and polypropylene (PP), which comprised 65% and 26% of water samples and 68% and 21% of wastewater samples. An ecological risk evaluation showed that the polymer hazard index (PHI) for water and wastewater was in the range of 17.4–22.6 and 201.-24.4, respectively, indicating hazard level III for both. The values of the pollution load index (PLI) and potential ecological risk index (PERI) for water and wastewater samples were lower than 10 and 150, which indicated a hazard level at I and a minor risk, respectively. Organic nitrogen and phosphorous, temperature, NO3–, NO2–, and total organic carbon were determined to be the physicochemical parameters with the most significant influence on MPs abundance in the Jajroud River by regularized canonical correlation analysis (RCCA).

RETRACTED: Microplastic pollution in intertidal sediments along the coastline of China

Much more attention has been poured into microplastic pollution in freshwater systems recently. In the present study, the pollution of microplastics (MPs) in surface water and freshwater fish (crucian carp, etc.) were investigated from Gehu Lake, which is the second largest lake in southern Jiangsu after Taihu Lake. The result manifested that the average abundance of MPs was respectively 6.33±2.67 n/L for surface water and 10.7 items per individual for freshwater fish. The distribution of MPs in Gehu Lake varied from place to place, with the highest abundance of MPs was observed in the two estuaries of the eastern part of the lake. It was speculated that topographical factors and human factors were the main factors affecting the abundance and distribution of MPs. Transparent fibers were the main type of MPs in water samples, accounting for 69.70% of all detected particles. Meanwhile, most of the MPs ingested by freshwater fish were fibers, and the main colors were transparent and blue. In addition, the dominant size of the MPs was between 0.1 to 0.5 mm in water and fish samples. Moreover, PES, man-made fiber, and PP were the dominant polymer types in the surface water and fish samples. The results of this investigation can provide basic data for the research and management of MPs in freshwater systems.

Occurrence, sources, and ecological risk of microplastics in groundwater: Impacts by agricultural activities and atmospheric deposition.

Assessment of hazardous microplastic polymers and phthalic acid esters in an invasive mollusk (Mytella strigata) from the Cochin estuary, southwest coast of India: Unraveling ecosystem risks.

Considering microplastic characteristics in ecological risk assessment: A case study for China

Microplastics (MPs) are widespread in aquatic environments and pose significant threats to ecosystems, wildlife, and human health. While MP pollution in water has received considerable attention, there is still limited understanding of its regional distribution, shapes, and associated risks. The Jamuna River, one of the largest freshwater ecosystems in Bangladesh, is increasingly contaminated by hazardous MPs, likely originating from industrial, domestic, hospital waste, and municipal sewage. This study aimed to investigate the abundance, distribution, characteristics, and ecological risks of MPs in the surface water of a highly urbanized large river in Southeast Asia. Water samples were collected from 30 sites along a 44 km stretch of the river during two periods: March to April (premonsoon) and July to August (monsoon). A total of 386 MPs were identified in the collected samples. The mean abundance of MPs in the surface water of the Jamuna River ranged from 0.01 to 0.15 MPs/L during the premonsoon season and from 0.01 to 0.13 MPs/L during the monsoon season. Approximately 79.78%–87.98% of the particles fell within the 100–1500 μm size range. The presence of polyethylene (31.60%–37.24%), polystyrene (PS) (6.71%–10.81%), and polyvinyl chloride (PVC) (5.64%–7.28%) contributed significantly to MP contamination, posing a high health hazard. Several risk assessment models were employed to evaluate the associated risks. The pollution load index (PLI) classified the contamination under risk Category I (minor pollution). Meanwhile, the polymer hazard index (PHI) values were 305.65 for the premonsoon season and 208.0 for the monsoon season, both indicating hazard Category IV (“danger” level). The potential ecological risk index (PERI) placed the Jamuna River surface water in the “extreme danger” risk category, with values of 2454.43 during the premonsoon and 1911.29 during the monsoon. The prevalence of high-hazard polymers such as PVC and PS suggests a potential risk of toxicological effects for aquatic organisms and humans through food web transfer. This baseline study provides valuable insights into the MP pollution of one of the country's major rivers. It may help improve our understanding of land-based MP inputs from inland water bodies severely impacted by anthropogenic activities.

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

Urbanization increases microplastic pollution in beach sediments along the Chennai Coast, South India.

An enhanced risk assessment framework for microplastics occurring in the Westerscheldt estuary

Microplastics (MPs) are emerging contaminants of increasing concern in terrestrial ecosystems, yet their distribution patterns and ecological risks in bamboo forest soils remain underexplored. We investigated MPs contamination in experimental Phyllostachys violascens forests under different urban proximity (suburban vs. exurban) and mulch durations (none, short‐term, and long‐term). MPs abundance, morphology, and polymer composition were analyzed across three soil depths (0–10, 10–20, and 20–40 cm) and correlated with soil properties. Ecological risks were assessed using potential ecological risk index ( H ) and pollution load index (PLI). The results were: MPs abundance varied significantly with urban proximity and mulching duration, with the highest levels observed in exurban and short‐term mulched stands. Vertical distribution showed an initial increase followed by a decline with depth. MPs were mainly granular, gray in color, and primarily composed of polymethyl methacrylate and polyethylene terephthalate. Increased distance from urban centers and longer mulching durations led to reduced diversity in MPs morphology and polymer types, and a shift toward smaller particle sizes (50–100 μm), particularly in short‐term mulched plots. MPs particle size was negatively correlated with the proportion of soil microaggregates ( p < 0.05), whereas polymer types showed significant positive correlations with soil pH, total nitrogen, hydrolyzable nitrogen, total potassium, and large aggregate proportion ( p < 0.05), indicating that soil properties influence MPs distribution and composition. PLI and H indexes indicated moderate MPs contamination, corresponding to ecological risk levels III–IV in all sampling sites. Overall, mulched Ph. violascens plantations exhibit moderate MPs contamination, with elevated ecological risks in exurban areas and under short‐term mulching. These findings provide insights for targeted mitigation strategies and improved management of MPs contamination in bamboo forest ecosystems.