Microplastic Emissions Research Articles

Forecasting global plastic production and microplastic emission using advanced optimised discrete grey model.

Plastic pollution has become a prominent and pressing environmental concern within the realm of pollution. In recent times, microplastics have entered our ecosystem, especially in freshwater. In the contemporary global landscape, there exists a mounting apprehension surrounding the manifold environmental and public health issues that have emerged as a result of the substantial accumulation of microplastics. The objective of the current study is to employ an enhanced grey prediction model in order to forecast global plastic production and microplastic emissions. This study compared the accuracy level of the four grey prediction models, namely, EGM (1,1, α, θ), DGM (1,1), EGM (1,1), and DGM (1,1, α) models, to evaluate the accuracy levels. As per the estimation of the study, DGM (1,1, α) was found to be more suitable with higher accuracy levels to predict microplastic emission. The EGM (1,1, α, θ) model has slightly better accuracy than the DGM (1,1, α) model in predicting global plastic production. Various accuracy measurement tools (MAPE and RMSE) were used to determine the model's efficiency. There has been a gradual growth in both plastic production and microplastic emission. The current study using the DGM (1,1, α) model predicted that microplastic emission would be 1,084,018 by 2030. The present study aims to provide valuable insights for policymakers in formulating effective strategies to address the complex issues arising from the release of microplastics into the environment and the continuous production of plastic materials.

Microplastic accumulation in oysters: Insights from aquaculture and laboratory conditions

Microplastics, emerging pollutants, are present in seafood and pose a potential health risk to consumers. The objective of this study was to assess microplastic concentrations in the surface water, sediments, and oysters of the Cha Va River, an aquaculture production area in southern Vietnam. Laboratory experiments were also conducted to examine rates of ingestion by and bioconcentration of microplastics in oysters. Microparticles including microplastics were measured in all samples collected from the field, and presented 9–27 items m−3 in surface water, 3300–8000 items kg−1 dry weight in sediments, and 0.67–8.33 items ind−1 or 0.02–0.33 items g−1 wet weight in oysters. Fibre shapes and blue colour were the most common while polypropylene, polyester, polyethylene, and polyethylene terephthalate acrylate, alkyd were identified. The presence of microparticles in surface water and sediment was influenced by the complex vertical motion characteristic of tidal environments whereas the microparticles in natural oysters seemed to be closer related to those in sediment than in the surface water. Laboratory experiments showed that oysters incubated in 10 and 1000 microplastics L−1 tanks accumulated 4.1 ± 2.0 and 19.0 ± 11.0 microplastics per individual, respectively. However, bioconcentration of microplastics in oysters was higher (12.37 ± 6.95) in tanks with lower microplastic concentrations than in tanks with higher microplastic concentrations (0.62 ± 0.35). It is a high potential human health risk to the local oyster-consumers because of the annually microparticle ingestion from 657 to 3942 items per person. We suggested further studies on the severity of this potential health risk and policies for minimising microplastic emissions into the environment in Vietnam.

Identification and Assessment of Potential Microplastic Emissions within the Lake Tollense Catchment Area, Mecklenburg-Western Pomerania, Germany

The present study was carried out within the MICROLIM project funded by the German Research Foundation DFG, which aims at an overall assessment of microplastic concentrations in different environmental compartments of the Lake Tollense catchment. Here, we address potential input sources of microplastic and their occurrence in the catchment and provide first estimates of emission volumes based on population density, agricultural activities and traffic. The land cover of the Lake Tollense catchment, located in Mecklenburg-Western Pomerania, Germany, is dominated by agriculture and comprises the city of Neubrandenburg in the Northern part of the lake and additional minor settlements in the rural areas. The catchment area is divided into six sub-catchments according to the lake’s tributaries. The methodological approach comprised (1) a literature review of potential sources of microplastic, their potential composition, application approaches and possible effects on the environment, (2) the determination of land use types within the lake Tollense catchment via a descriptive land-use analysis and examination of the identified land-use types for the occurrence of microplastic-emitting applications according to the initial literature review and (3) a quantitative estimation of the emission volumes of the population (including tourists), transport and agricultural activities in the catchment area, applying specific emission rates. Potential microplastic emissions could be identified from urban agglomerations and the agricultural and transport sectors. The first quantifications of the emission potential of particulate matter in the size of 10 µm (PM10) from the transport sector resulted in an average of 14.5 tons per year on state and federal roads. The total annual emission volume of the population in the study area is estimated at an average of 138.6 tons per year. The calculated volumes of particulate emissions from roads and traffic indicate that transport is the most important emission source in the Lake Tollense catchment area.

Ocean emission of microplastic.

Microplastics are globally ubiquitous in marine environments, and their concentration is expected to continue rising at significant rates as a result of human activity. They present a major ecological problem with well-documented environmental harm. Sea spray from bubble bursting can transport salt and biological material from the ocean into the atmosphere, and there is a need to quantify the amount of microplastic that can be emitted from the ocean by this mechanism. We present a mechanistic study of bursting bubbles transporting microplastics. We demonstrate and quantify that jet drops are efficient at emitting microplastics up to in diameter and are thus expected to dominate the emitted mass of microplastic. The results are integrated to provide a global microplastic emission model which depends on bubble scavenging and bursting physics; local wind and sea state; and oceanic microplastic concentration. We test multiple possible microplastic concentration maps to find annual emissions ranging from 0.02 to 7.4-with a best guess of 0.1-mega metric tons per year and demonstrate that while we significantly reduce the uncertainty associated with the bursting physics, the limited knowledge and measurements on the mass concentration and size distribution of microplastic at the ocean surface leaves large uncertainties on the amount of microplastic ejected.

Abundance, characteristics and seasonal variation of microplastics in a domestic sewage treatment plant in Nanjing, China

Sewage treatment plants are a potential route of microplastics (MPs) into the environment, hence it's urgent to investigate MPs in wastewater and sludge through lengthy sampling campaigns. In this study, a sewage treatment plant in Nanjing, China was chosen, seasonal variation of MPs in influent was analyzed by collecting samples during a 12-month sampling campaign (at monthly intervals over a one-year period). Abundance and characteristic of MPs from different treatment stages were also investigated. The results showed that there was a seasonal variation in the amount of MPs in influent and the abundance of MPs was significantly greater in summer than other seasons. The average MPs abundance was 41.0 items/L and 3.0 items/L in influent and effluent, with a total 92.6 % removal rate. Overall, 125–355 μm were the main size in each treatment section, with fibers dominant shape and transparent main color. Additionally, the primary polymer compositions of MPs were polyethylene (PE) and polypropylene (PP) using micro-Roman spectroscopy. The daily MPs emission from effluent and sludge was estimated to be 300 million and 1274 million items/d, demonstrating that the sewage treatment plant is an important source of MPs into the environment despite the high removal rate of MPs.

Estimation of microplastic emission and transfer into Tokyo Bay, Japan, using material flow analysis

To reduce microplastic (MP) discharge into the aquatic environment, it is necessary to properly identify its sources and amounts. Here, specific MP sources, i.e., personal care products (PCPs), fibers from clothes, and tire-wear particles (TWPs) were focused, and MP generations from these sources in the Tokyo Bay watershed, Japan, were estimated based on statistical data on production and reported emission factors of the MP sources and executing considering uncertainty on the data. Potential annual MP emission into Tokyo Bay was estimated to be 10.2 ± 1.6, 38 ± 22, and 1500–1800 tons for PCPs, fibers, and TWPs, respectively. Emissions into Tokyo Bay by assuming MP density and diameter was estimated. For fiber, the fraction to potential emission was estimated at 1.0–2.8 %. This study contributes to determining potential discharge pathways. This will assist in the application of appropriate measures to reduce MP discharge into water bodies.

Modelling the Potential Long-Range Dispersion of Atmospheric Microplastics Reaching a Remote Site

The study of the microplastic dispersion in the atmosphere is a relatively new field of research. In the studies available in literature, it was suggested that long-range transport may play a main role in the motion of microplastics towards remote sites, where no significant local sources are present. In this framework, here the Lagrangian particle dispersion model MILORD was used in the backward mode to investigate the potential long-range dispersion of microplastics in the atmosphere and to assess possible source areas that may determine microplastic pollution in a remote site. The chosen case study refers to the work of Allen et al. (2019), who analysed the observations of atmospheric microplastics deposition in a remote and pristine site in the French Pyrenees, also through numerical backward trajectories. Based on their dataset, they showed that microplastics could arrive at the site from distances up to about 100 km. Yet, they considered that it was unlikely to have only microplastic emissions from local sources, because of the low population density in the area. The results of MILORD simulations for different periods showed that for this case study the dominant scale of the microplastics transport process is regional up to mesoscale, while long-range transport may contribute when the tracer is mostly travelling in the free atmosphere before being deposited at the site. The relative contributions of dry and wet depositions and corresponding rates were also assessed. It was confirmed that plastic particles characterised by the highest settling velocities, reasonably associated to large particles, are unlikely to be subjected to long-range transport.

Tire Wear and Pollutants: An Overview of Research

Tire Road and Wear Particles are a major source of microplastic emissions. Tire and Road Wear Particles are important to study and understand as there are alarming amounts found in various environments. Currently, Tire and Road Wear Particles compared to other microplastics are not studied as rigorously in literature but are becoming a larger field of study due to their impact on emissions control. Tire Road and Wear Particles are commonly found as Styrene Butadiene Rubber Butadiene Rubber, and Natural Rubber To understand and quantify tire wear, experimental and mathematical models are developed to estimate tire wear. Tire wear can be measured experimentally using semi-empirical models, predetermined data, and sensor technologies. Tire wear is also measured mathematically using different modeling approaches and different friction models. This review discusses different and popular methodologies for estimating tire wear through experimental and simulated environments. Furthermore, discusses a review of the literature regarding tire wear emissions and its impact on the environment. Finally, it is evident that an accurate simulated tire wear model can be developed in the future alongside a driver model to predict tire wear emissions.

Modified polyamide fibers with low surface friction coefficient to reduce microplastics emission during domestic laundry

The widespread presence of microplastics has become a serious threat to humans and ecological environments because they carry many pollutants and can be easily ingested by aquatic organisms. Fibrous microplastics (FMPs) released from synthetic fiber garments during domestic laundry are a major source of contamination. Herein, we report a facile FMPs mitigation strategy for polyamide 6 (PA6) fibers by incorporating environmentally friendly polydimethylsiloxane (PDMS) during melt spinning. The obtained PA6/PDMS fibers showed a lower friction coefficient than the pure PA6 fibers. Surface morphology, tribology, and washing characterizations verified that a 60% reduction in FMPs shedding was achieved by reducing the friction. In addition, the low-surface-friction PA6/PDMS fabrics with high hydrophobicity exhibited improved waterproof and anti-stain behaviors. It is important to note that none of the essential properties, such as surface structure, dyeing and printing of the fabrics were compromised after PDMS blending. This study provides a green and scalable route for mitigating laundry microfibers using a fiber domain design.

Recycling of Plastics as a Strategy to Reduce Life Cycle GHG Emission, Microplastics and Resource Depletion

Plastic waste is the most challenging type of waste because its generation rate (consumption rate) is high, and the current recycling rate is low. The increase in the production and disposal of plastics has led to significant environmental problems including greenhouse gas (GHG) emissions, microplastic pollution, and resource depletion. The study aimed at quantifying the potential environmental effects reduction achieved by recycling the most widely consumed polymers. One approach to establishing a circular economy for plastics is recycling. Plastic recycling as a strategy to reduce life cycle GHG emissions, microplastic emissions, and resource depletion was investigated. Life cycle assessment methodology was employed, considering cradle-to-gate as a system boundary. The results showed that recycling can significantly reduce life cycle GHG emissions and resource depletion. Replacing the virgin material with recycled material reduces the emission to −67 MtCO2e. Recycling could have saved 56.8 million microplastic emissions per year. However, mechanical recycling, which is commercialised nowadays, contributed to an increase in microplastics as much as 2.4 × 109 million particles per year. Recycling will also save about 50 million tonnes of resources from depletion worldwide by recycling around 20 Mt plastics. However, microplastic emissions reduction in the present scenario of mechanical recycling is not possible unless other mechanisms to capture the emitted microplastics are introduced or other recycling methods, such as chemical recycling, are employed.

MarILCA characterization factors for microplastic impacts in life cycle assessment: Physical effects on biota from emissions to aquatic environments

Although plastics emissions pose hazards to ecosystem quality, life cycle assessment (LCA) methodologies do not yet include quantification of the potential impacts of plastic leakage. To address this gap in LCA, the MarILCA working group was founded. This work contributes to MarILCA's output by providing characterization factors for assessing the impacts of aquatic (marine and freshwater) microplastic emissions through the impact category of physical effects on biota and ultimately the ecosystem quality damage category. First, the existing exposure and effect factor (EEF) for micro- and nanoplastic emissions in aquatic compartments (Lavoie et al., 2021) is updated using additional toxicity data, delivering a generic EEF of 1067.5 PAF m3/kgin compartment. Second, fate factors (FFs) are developed for eleven different polymers (EPS, PS, PA/Nylon, PP, HDPE, LDPE, PET, PVC, PLA, PHA, TRWP), three shapes (sphere/microbead, cylinder/microfiber, microplastic film fragments) and five sizes (1, 10, 100, 1000, 5000 μm). To calculate the FFs, a detailed degradation model and a simplified sedimentation model are proposed. Polymer density and size play a major role in the fate, whereas the influence of the shape is less relevant. Ultimately, the EEF and FFs are combined to deliver midpoint and endpoint characterization factors (CFs). Uncertainty is calculated with Monte Carlo analysis. Default and archetype-based CFs are recommended to LCA practitioners in case the details of emission parameters are not fully known. CFs for 1 μm microplastic size are proposed as interim CFs for nanoplastic emissions. Finally, endpoint CFs are tested in case studies within the UNEP report “Supermarket food packaging and its alternatives: Recommendations from life cycle assessments”, assessing the relative magnitude of potential microplastic impacts compared to complete LCA results. The case studies confirm that the proposed methodology contributes to filling a gap in LCA and can assist environmental decision-making on single-use plastics and their alternatives.

The destiny of microplastics in one typical petrochemical wastewater treatment plant

Microplastic (MP) is a type of emerging contaminant that is verified to be threatening to some organisms. Controlling MP emission from the source is preferred for its refractory characteristic. The petrochemical industry is a possible contributor, responsible for the most plastic production, and wastewater is the most possible sink of MP. This study applied the Agilent 8700 Laser infrared imaging spectrometer (LDIR) to detect MPs in one typical petrochemical wastewater treatment plant (PWWTP). It was determined that the abundances of MPs in the influent and effluent of the target PWWTP were as high as 7706 and 608 particles/L. The primary treatment removed most MPs (87.5 %) with a final removal efficiency of 92.1 %. 23 types of MPs were identified, and Polyethylene (PE), Polypropylene (PP), Silicone resin prevailed in the effluent. All the MPs were smaller than 483.9 μm. All in all, this study preliminarily unveiled the ignorable status of the petrochemical industry in releasing MPs into the water environment for the first time.

Assessment of road run-off and domestic wastewater contribution to microplastic pollution in a densely populated area (Flanders, Belgium)

Plastics are omnipresent in our daily life. Unfortunately, the produced plastics will partly end up in the environment including aquatic ecosystems. People often refer to littering or illegal waste dumping as sources of plastic emission to the environment. However, daily-life sources could also, unknowingly, contribute considerably to the total microplastic pollution in the ecosystem. Hence, there is an urgent need to study these potential sources. In this research, two common sources, i.e. domestic wastewater and road run-off from tire and road wear particles, were studied in detail to quantify the relative contribution of both domestic sources towards microplastic pollution in freshwater ecosystems in Flanders, Belgium.This assessment shows that every person (in studied area) emits on average 1145 microplastics (25–1000 μm) daily through domestic wastewater, resulting in a yearly discharge of 418,000 microplastic particles per person. The road run-off samples contained between 0.02 and 9.2 mg tire wear particles per litre per day, which corresponds to an emission of 10.8 mg tire wear particles per driven vehicle km.The gross and net emissions of both above mentioned microplastic sources were extrapolated to the whole Flanders region using an emission model. From the yearly gross microplastic pollution in the domestic wastewater, 623 kg (20%) will be discharged in the freshwater. The highest losses originated from the households that have a private drain or are not (yet) connected to an active wastewater treatment plant. In Flanders, the yearly net microplastic emission into the aquatic environment of tire wear particles is estimated to be 246 tonnes (38%), mainly from the direct run-off from the road surface. Based on the results, specific mitigation measures can be installed to reduce the emission of microplastics towards the freshwater ecosystem. Other sources should be quantified in a similar way for a more holistic strategy to counteract plastic pollution.

Potential contamination of microplastic from plastic recycling enterprises in Ho Chi Minh City, Vietnam

The widespread presence of microplastics (MPs) in water raises serious concerns on a global scale due to the negative effects on human health and ecosystems. Wastewater and sludge from preliminary plants of recycled plastic pellets are a significant continuous source of MP discharged into the environment. Wastewater and sludge samples were collected from three plastic recycling plants and analyzed for MPs (size from 0.15–5 mm). The average rate of MP emission was approximately 5.8–6.6% of the total investigations. The MP in water ranged from 14.3410 to 19.3395 g/l, of which 40% with size 2–5 mm, 32% (1–2 mm), 5% (0.5–1 mm), 14% (0.15–0.5 mm), and 9% with size less than 0.15 mm in average. MP in sludge varied from 472.2031 to 644.7620 g/kg, of which, 37% with size 2–5 mm, 24% (1–2 mm), 9% (0.5–1 mm), 12% (0.15–0.5 mm) and 18% less than 0.15 mm. In average, 2,695 particles/l and 287,600 particles/kg of MP size 0.15–5 mm was found in wastewater and sludge, which may have a potential risk to aquatic fauna and humans. Therefore, control microplastic emission from those sources will contribute significantly to reducing microplastics entering the surrounding environment.

Microplastic formation and simultaneous release of phthalic acid esters from residual mulch film in soil through mechanical abrasion

The application of plastic mulch film could effectively enhance the productivity of facility agriculture. However, releasing microplastic and phthalate from mulch films in soil has attracted increasing concerns, and releasing characters of microplastic and phthalate from mulch films during their mechanical abrasion remains unclear. This study elucidated the dynamics and impact factors of microplastic generation, including the thickness, polymer types and ageing of mulch film during mechanical abrasion. Releasing characters of the di(2-Ethylhexyl) phthalate (DEHP), a common type of phthalate in soil, from mulch film during mechanical abrasion were also explored. Results showed that 2 pieces of mulch film debris increased to 1291 pieces of microplastic after five days of mechanical abrasion, with exponential growth in the microplastic generation. After mechanical abrasion, the thinnest (0.008 mm) mulch film completely transformed into microplastics. However, the thicker mulch (>0.01 mm) suffered slight disintegration, making it feasible to be recycled. The biodegradable mulch film discharged the most microplastics (906 pieces) compared with the HDPE (359 pieces) and LDPE (703 pieces) mulch film after three days of mechanical abrasion. In addition, the mild thermal and oxidative ageing could result in 3047 and 4532 pieces of microplastic emissions from mulch film after three days of mechanical abrasion, which were ten times more than the original mulch film (359 pieces). Furthermore, negligible DEHP was released from mulch film without mechanical abrasion, while the released DEHP significantly correlated with generated microplastics during mechanical abrasion. These results demonstrated the crucial role of mulch film disintegration in phthalate emissions.

Seasonal pulse effect of microplastics in the river catchment-From tributary catchment to mainstream

Rivers have received extensive attention as a major pathway for microplastics (<5000 μm) from land to ocean. This study investigated the seasonal variation of microplastic contamination in surface water of the Liangfeng River catchment, a tributary of the Li River in China, based on a fluorescence-based protocol, and further explored the migration process of microplastic in the river catchment. The abundance of microplastics (50–5000 μm) was (6.20 ± 0.57)–(41.93 ± 8.13) items/L, of which 57.89–95.12% were small-sized microplastics (<330 μm). The microplastic fluxes in the upper Liangfeng River, lower Liangfeng River, and upper Li River were (14.89 ± 1.24) × 1012, (5.71 ± 1.15) × 1012, and (1.54 ± 0.55) × 1014 items/year, respectively. The 3.70% of microplastic load in the mainstream came from the tributary input. Fluvial processes can effectively retain 61.68% of microplastics in the surface water of river catchments, especially for small-sized microplastics. The rainy season is the main period of microplastic retention (91.87%) in the tributary catchment by fluvial processes, while exporting 77.42% of one-year microplastic emissions from the tributary catchment into the mainstream. This study is the first to reveal the transport characteristics of small-sized microplastics in river catchments based on flux variation, which not only can partly explain the “missing small-sized microplastic fraction” in the ocean, but also contribute to improving microplastic model.

Modeling atmospheric microplastic cycle by GEOS-Chem: An optimized estimation by a global dataset suggests likely 50 times lower ocean emissions

Modeling atmospheric microplastic cycle by GEOS-Chem: An optimized estimation by a global dataset suggests likely 50 times lower ocean emissions

Aging, characterization and sorption behavior evaluation of tire wear particles for tetracycline in aquatic environment

Accounting for more than half of the total primary microplastic (MP) emissions, and one-sixth of the total marine MP pollution in China in 2015, tire wear particles (TWP) are inevitable to age and interact with co-existing species, thus pose a potential risk to the surroundings. The impacts of simulated ultraviolet radiation weathering and liquid-phase potassium persulfate oxidation of TWP on the surface physicochemical properties were comparatively explored. The characterization results demonstrated that the content of carbon black, particle size and specific surface area of the aged TWP all decreased, while the changes of the hydrophobicity and polarity were inconsistent. The interfacial interactions with tetracycline (TC) in aqueous were investigated, the well fitted pseudo-second-order kinetics, Dual-mode Langmuir and Scatchard isotherm models indicated the attachment of TC dominated by surface adsorption at lower concentration, and there's a positive synergistic effect among the main sorption domains. Moreover, the results of the influences of co-existing salts and natural organic matter revealed that the potential risks of TWP elevated by the adjacent media in natural compartment. This work provides new insights into the way that TWP interact with contaminants in the real environment.

Microplastic emission trends in Turkish primary and secondary municipal wastewater treatment plant effluents discharged into the Sea of Marmara and Black Sea

Wastewater Treatment Plants (WWTPs) are recognized as one of the primary sources of microplastics, a class of contaminants that has lately gained attention. The quantity of MP that WWTPs release into the environment depends on several factors, including the treatment type, season, and population serviced. MP abundance and characterization were explored in 15 WWTP effluent waters, 9 discharged to the Black Sea from Türkiye and 6 to the Marmara Sea, with varying population densities and treatment methods. The mean MP abundance in primary treatment WWTPs (76.25 ± 49.20 MP L−1) was found to be substantially greater than that in secondary treatment WWTPs (20.57 ± 21.56 MP L−1) (p<0.05). MPs in WWTP effluent waters showed significant seasonal and spatial differences (Two Way ANOVA, Tukey, p<0.05). However, no positive correlation was detected between the population serviced and MP abundance in effluent waters. While the fiber was the dominant shape (49.5%) among MPs in effluent waters, ≈80% of the length was <1000 μm. MPs are classified into polymer types as follows: polyethylene terephthalate (34.9%) > polypropylene (32.4%) > polyethylene (19.9%) > polyamide (11%) > polystyrene (1.2%) > polyvinyl chloride (0.6%). With effluent waters from the WWTPs tested, we calculated that 1.24x1010 daily MPs are discharged into the Black Sea while 4.95x1010 MPs are into the Marmara Sea, for a combined annual discharge of 2.26x1013 MPs highlighting that WWTPs are key contributors of MP in Turkish coastal waters.

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.