Occurrence Of Microplastics Research Articles

Occurrence and characteristics of microplastics across the watershed of the world’s third-largest river

While rivers as primary conduits for land-based plastic particles transferring to their "ultimate" destination, the ocean, have garnered increasing attention, research on microplastic pollution at the scale of whole large river basins remains limited. Here we conducted a large-scale investigation of microplastic contamination in water and sediment of the world’s third-largest river, the Yangtze River. We found concentrations of microplastics in water and sediment to be 5.13 items/L and 113.9 items/kg (dry weight), respectively. Moreover, microplastic pollution levels exhibited a clear decreasing trend from upstream to downstream. The detected microplastics were predominantly transparent in color, with fibrous shapes predominating, sizes mainly concentrated below 1mm and composed primarily of PP and PE polymers. Our analysis results indicated that compared to geographical and water quality parameters, anthropogenic factors primarily determined the spatial distribution pattern of microplastics. Moreover, the microplastic abundance in sediment upstream of the dam was significantly higher than that in the downstream sediment, while the trend of microplastic concentrations in water was opposite. Therefore, more effort is needed to monitor microplastic contamination and their ecological environmental effects of sediment before dams in future research.

The synchronized dynamic release behavior of microplastics during farmland soil erosion process

Microplastics (MPs) are widespread in farmland soil. However, the risks associated with their loss through soil erosion remain unknown. This study investigates the occurrence and behavior of MPs in farmland soil in a southeastern coastal area of China, focusing on their synchronized dynamic release during soil erosion scenarios. The results showed that the abundance of MPs in the tested farmland soil ranged from 2.40×104 to 1.04×105 items·kg-1. MPs predominantly appear as fragments and particles, with sizes concentrated between 30-100 μm. During the process of soil erosion, characterized by rapid soil subsidence, the amount of MPs released into water bodies initially decreases, averaging a reduction of 1.08×104 items·kg-1. This is followed by an average increase of 1.89×104 items·kg-1. The competition between the adsorption, collision, and sedimentation of soil particles and the desorption and release of settled particles, determines this behavior. This pattern is strongly related to the physicochemical properties and mechanical composition of the soil. Deep learning predictions revealed that, without external influences, 49.42% of MPs in farmland soil could be synchronously released into water bodies during erosion. The analysis shows that MPs exhibit dynamic behavior in time and space, posing serious threats to aquatic ecosystems. Controlling soil erosion in farmland is crucial for the source management of MP migration.

Microplastic in Abiotic and Biotic Parts of the Mesha Bay of the Kuibyshev Reservoir (Republic of Tatarstan)

The study of microplastic content in water, sediments, gills and gastrointestinal tract of bream (Abramis brama) at the mouth of the Mesha River, the right tributary of the Kama River, was conducted. The content of microplastics in water was found at the level of 20.5 ± 22.3 units/m3, in bottom sediments 44.7 ± 41.8 units/kg, in fish gills 12.3 ± 8.4 units/example, in the gastrointestinal tract 14.5 ± 11.5 units/example. Fibers dominated in water samples, in the gills and gastrointestinal tract of fish, fragments dominated in the sediment. Correlation analysis showed the presence of a negative relationship between the content of microplastics in the gills, gastrointestinal tract and biologic indicators of studied fish. In terms of the frequency of occurrence and content of microplastics in the gills and gastrointestinal tract, the contamination of the studied fish is at a high level compared to literature data, which is associated with the feeding behavior of bream.

Extraction and analysis of microplastics in wastewater sludges of a multi-product pulp and paper mill

Pulp and paper wastewater sludges are waste streams produced in major quantities across the world. The recycling of these organic sludges, for example to soil amendments, is desired in the circular economy but carries the risk of potential pollutants to be also introduced into the environment. Pulp and paper wastewater sludges have been scarcely studied matrices in the microplastic research due to their complex composition. In this study, we optimized an extraction process for microplastics from pulp and paper wastewater sludges, and quantified and characterized microplastics down to 20 μm in primary sludge and biosludge generated at the wastewater treatment plant of a multi-product pulp and paper mill in Finland. The occurrence of microplastics was high in primary sludge, 900–1600 microplastics g−1 dry weight, while the maximum number of detected microplastics in biosludge samples remained at 210 g−1 dry weight. Biosludge samples suffered from larger amounts of remaining solids after the extraction process, thus compromising the detection of smaller microplastics (<100 μm) and increasing the uncertainty related to the interpretation of the results. The most prevalent microplastic shape in all samples was fragment, and the most recurring polymer types were polyethylene and polypropylene, while a polystyrene-based copolymer represented approximately 10% of identified microplastics in primary sludge. The present study advances the development of microplastic analysis of the challenging pulp and paper wastewater sludges and brings novel information to the progressing discussion of their circulation potential.

Fibrous foes: First report on insidious microplastic contamination in dietary fiber supplements

Regular consumption of health supplements to balance dietary intake has gained popularity worldwide. One such supplement that has gained popularity among consumers is dietary fibers. Microplastic (MPs) contamination in various food products is being reported worldwide. However, there is a paucity of understanding of the occurrence of MPs in dietary supplements. This study addresses this gap by investigating the degree of MPs contamination in dietary fiber supplements. Nine commonly consumed (powder and gummy-based) over-the-counter dietary fiber supplements in Australia were tested in this study. Microscopic examination revealed the presence of MPs fibers and fragments in all the tested products. Further categorization showed that MPs particles were of various colours, including black, blue, red, green, and white. The order of polymer abundance was Polyamide > Polydiallyl Phthalate > polyethylene polypropylene diene > Polyurethane = Polyethylene terephthalate > Polyethylene = Ethylene acrylic acid copolymer. Among the supplements, powder-based samples had higher MPs (at the adult dosage suggested by the manufacturer) than gummy-based product. The average predicted ingestion of microplastics from these supplements (all nine samples) was 5.89 ± 2.89 particles day−1. The dietary exposure for children and adults ranged from 0.1–0.48 and 0.18–4.08 particles day−1, respectively. Based on the microplastic contamination factor (MCF), among the nine samples tested, 69.81% exhibited a moderate level, while 20.76% showed a significant level of microplastic contamination. The polymer risk index (pRi) indicates products with very high and high-risk categories. The possible sources of MPs contamination in the products were studied. To our knowledge, this is the first study to record and quantify the presence of MPs in dietary fiber supplements, which is a direct source of MPs exposure to humans via., ingestion.

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

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

Insights into the seasonal variation, distribution, composition and dynamics of microplastics in the Ganga River ecosystem of Varanasi City, Uttar Pradesh, India.

The current study explores the seasonal dynamics of microplastic (MP) pollution in the Ganga River of Varanasi City, Uttar Pradesh, India, focusing on water and sediment samples collected during pre-monsoon and post-monsoon periods. The analysis shows significant variations in MP occurrence, shape dynamics, color distribution, and size composition across diverse sampling sites. During the pre-monsoon season, MP concentrations ranged from 17 to 36 particles/L in water samples and 160 to 312 particles/kg in sediment, indicating a moderate to high level of contamination. Post-monsoon sampling showed higher MP concentrations at most sites, indicating the influence of seasonal hydrological changes on MP distribution. Shifts in MP shape dynamics were observed between seasons, with films, foams, fragments, and filaments showing variable distributions. Similarly, color variations in MPs exhibited site-specific patterns, with white, brown, blue, and other colors being predominant. These findings highlight the diverse sources and compositions of MPs in the river ecosystem, highlighting the complexity of MP pollution dynamics. Polymer-type distributions further elucidated the composition of MPs, with notable contributions from polyethylene terephthalate, rayon, polyester, and polyvinyl chloride. PCA analysis revealed significant shifts in particle size and shape distribution between pre-monsoon and post-monsoon periods in both water and sediment samples, with post-monsoon samples showing an increase in larger particles and filaments. These changes highlighted key factors driving the variance in microplastic contamination across different sites. The prevalence of these polymers features diverse sources of MP pollution, including textiles, packaging materials, and industrial waste. Ongoing monitoring and research are crucial to understanding its sources, distribution, and impact on river ecosystems, essential for protecting aquatic biodiversity and human health.

Assessment of microplastic characterization and distribution from surface water and the seabed in the Flores Sea, Indonesia

Despite growing global concerns, there has been limited research on the characterization and distribution of microplastics in the Indonesian Throughflow (ITF) pathways, such as the Flores Sea. The Flores Sea is a component of the Indian–Pacific Current, a significant ocean current system that links the Pacific and Indian oceans and has the capacity to carry pollution over large marine ecosystems, making this research extremely important. Understanding the microplastic pollution in this area informs local environmental management. It provides insights into how these currents may distribute microplastics (MPs) across regional and global scales, impacting marine life and human health far beyond the immediate area. To respond to these concerns, this research aims to determine the characterization and distribution of MPs at six research sites in the Flores Sea that are precisely located within the ITF. This work exhibits an extensive dataset focusing on the occurrence, attributes, and dispersion of microplastics in the Flores Sea. The water sampling was carried out during a Jala Citra 3 by the Indonesian Navy from April to May 2023. Sea surface water samples were collected using a Neuston net, while sediment samples were taken from three stations at the shallowest depth using the Ekman Grab sampler. Additionally, abundance, size, shape, and color analyses were conducted using a light microscope, and microplastic types were identified through Raman spectroscopy. The results indicated that the Flores Sea waters and sediment are polluted with microplastics, with relative abundances ranging from 0.75 ± 0.49 to 2.13 ± 0.25 items/l samples. The most dominant shapes identified were filament (77.45%) and fragment (13.40%), with sizes varying between surface water 4.70 to 3799.25 μm and seabed from 67.20 mm to 2176.87 mm, while black (30.07%) and blue (24.51%) were reported as the common MPs colors. The identified polymers include PET and PE. This study confirms visual evidence of microplastics in the open waters of eastern Indonesia. While it may not fully capture the wide range of temporal variations, it establishes initial microplastic presence and dispersion levels. Given that the ITF influences both the Pacific and Indian Oceans, this research contributes to the global understanding of microplastic distribution across ocean basins, underscoring the need for coordinated international efforts to address marine pollution.

Occurrence and risk assessment of microplastics on the Shenzhen coast, South China

Microplastics (MPs) have attracted increasing attention worldwide owing to their widespread presence and potential risks to terrestrial and marine ecosystems. Estimating the pollution status and risk levels of MPs in coastal ecosystems is necessary; however, these are poorly understood in coastal megacities. Here, the abundance and characteristics of MPs in seawater, marine sediment, marine organisms, and beaches in the Shenzhen coastal ecosystems and land sources (river and sewage outfall) were simultaneously investigated, and the annual MPs load of rivers and MP-induced ecological risks were evaluated. The results showed that MPs pollution was prevalent in Shenzhen coastal ecosystems, with the average abundances of 2.40 ± 2.48 items/m3, 404.21 ± 431.48 items/kg, 1.66 ± 1.96 items/individual, and 1648.99 ± 1908.19 items/kg in seawater, marine sediment, marine organisms, and beach sands, respectively. The detected MPs were predominantly fibrous/granular, transparent/white, < 1 mm in size, and polyethylene terephthalate/polyethylene/polystyrene. The spatial distribution patterns of marine MPs are influenced mainly by anthropogenic activities and freshwater inflows (rivers and sewage outfalls). Pollution hotspots of MPs were identified in the Pearl River Estuary, which has a high population, gross domestic product, and river and wastewater discharge. Furthermore, the negative correlation between the abundance of MPs in seawater and salinity indicates that freshwater inflow carrying MPs to the sea is an important source of marine MPs pollution. It has been estimated that approximately 8320 billion MPs particles, weighing 274.55 tons, flow into the Shenzhen coast annually through river input. Based on the MPs polymer types and quantities, the ecological risk of MPs pollution in the Shenzhen coastal ecosystem is moderate and deserves further attention. These findings deepen the understanding of MPs pollution, sources, and ecological risks in the southern coastal region of China, and are helpful for employing effective management strategies to control marine MPs pollution.

Microplastic accumulation and transport in agricultural soils with long-term sewage sludge amendments

Land application of sewage sludge brings microplastic contamination to soil. However, studies regarding the occurrence and mobility of sludge-borne microplastics in soil are insufficient. In the present study, based on an experimental field, the effects of sludge application amount on the accumulation and migration of microplastics in 0–20 (upper) and 20–40 cm (lower) soil layers were evaluated. After 16 years of continuous sludge application (36 t/ha per year), the microplastic content and migration ratio in upper soil reached 6811 particles/kg and 148 %, which was about 5 and 20 times, respectively, higher than that of the control soil without sludge. The microplastics in upper and lower soil layers, were mainly 0.2–0.5 mm in size, mostly fibrous in shape, primarily transparent in color, and predominantly rayon in composition. Microplastic surfaces may persistently adsorb clay minerals and iron/titanium oxides from soil, posing potential environmental risks. Sludge application had a significant positive correlation with soil microplastic abundance, resulting in a good fit of predictive model constructed for microplastic accumulation in sludge-amended soils. These findings help to improve the knowledge on environmental behavior of microplastics in sludge-amended soil, and can provide a scientific basis for the regulation of microplastic pollution during sludge land application.

A multiple biomarker approach to understand the effects of microplastics on the health status of European seabass farmed in earthen ponds on the NE Atlantic coast

The occurrence of microplastics (MPs) in aquaculture environments is a growing concern due to their potential negative effects on fish health and, ultimately, on seafood safety. Earthen pond aquaculture, a prevalent aquaculture system worldwide, is typically located in coastal and estuarine areas thus vulnerable to MP contamination. The present study investigated the possible relation between MP levels of European seabass (Dicentrarchus labrax) farmed in an earthen pond and its health status. More precisely, two groups of fish were established based on the lowest and highest number of MPs found collectively in their gastrointestinal tract (GIT), liver, and dorsal muscle: fish with ≤2 MP/g and fish with ≥4 MP/g. The intestinal integrity and oxidative stress biomarkers in the liver and dorsal muscle were evaluated in the established groups. No significant differences in the biometric and organosomatic parameters between groups were observed. The results indicated a significant increase in the number of acid goblet cells (GC) in the rectum of fish with higher MP levels (p = 0.016). Increased acid GC number may constitute a first defence strategy against foreign particles to protect the intestinal epithelium. No significant differences in oxidative stress biomarkers between the two fish groups were observed, namely in the activity of superoxide dismutase, catalase, glutathione reductase, and glutathione S-transferase in the liver, or in lipid peroxidation levels in the liver and dorsal muscle. The overall results suggest that MP levels were possibly related to an intestinal response but its potential implications on the health status of pond-farmed seabass warrant further investigation. Monitoring MP occurrence across stages of aquaculture production could help to elucidate the potential threats of MPs to fish health.

Combined toxicity of perfluoroalkyl substances and microplastics on the sentinel species Daphnia magna: Implications for freshwater ecosystems

Persistent chemicals from industrial processes, particularly perfluoroalkyl substances (PFAS), have become pervasive in the environment due to their persistence, long half-lives, and bioaccumulative properties. Used globally for their thermal resistance and repellence to water and oil, PFAS have led to widespread environmental contamination. These compounds pose significant health risks with exposure through food, water, and dermal contact. Aquatic wildlife is particularly vulnerable as water bodies act as major transport and transformation mediums for PFAS. Their co-occurrence with microplastics may intensify the impact on aquatic species by influencing PFAS sorption and transport. Despite progress in understanding the occurrence and fate of PFAS and microplastics in aquatic ecosystems, the toxicity of PFAS mixtures and their co-occurrence with other high-concern compounds remains poorly understood, especially over organisms’ life cycles.Our study investigates the chronic toxicity of PFAS and microplastics on the sentinel species Daphnia, a species central to aquatic foodwebs and an ecotoxicology model. We examined the effects of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and polyethylene terephthalate microplastics (PET) both individually and in mixtures on Daphnia ecological endpoints. Unlike conventional studies, we used two Daphnia genotypes with distinct histories of chemical exposure. This approach revealed that PFAS and microplastics cause developmental failures, delayed sexual maturity and reduced somatic growth, with historical exposure to environmental pollution reducing tolerance to these persistent chemicals due to cumulative fitness costs. We also observed that the combined effect of the persistent chemicals analysed was 59% additive and 41% synergistic, whereas no antagonistic interactions were observed. The genotype-specific responses observed highlight the complex interplay between genetic background and pollutant exposure, emphasizing the importance of incorporating multiple genotypes in environmental risk assessments to more accurately predict the ecological impact of chemical pollutants.

Microplastic and associated emerging contaminants in marine fish from the South China Sea: Exposure and human risks

Microplastics can act as vectors of chemical contaminants in aquatic environments, but the extent to which this phenomenon contributes to chemical exposure in marine organisms remains poorly understood. We investigated the occurrence of microplastics and emerging contaminants (ECs), including antibiotics and per- and polyfluoroalkyl substances (PFAS) in 14 marine fish species. Microplastics were detected in all marine fish species, mainly in the gastrointestinal tract. Fluoroquinolones and tetracyclines were the dominant antibiotics in fish muscles with maximum concentrations of 24.84 and 26.95 ng g−1 ww, while perfluorooctanesulfonic acid (PFOS, 0.039–0.95 ng g−1 ww) was the dominant component in the PFAS profile. Fish with more microplastics had significantly higher concentrations of fluoroquinolones and perfluoroalkyl acids than fish with less microplastics (p < 0.05), but the correlation was not observed in other chemicals. Structural equation modeling revealed the contribution of microplastics in fish on the level of ECs contamination. The health quotient value indicated the low health risk of single compounds via fish consumption to humans; however, the combined risk of microplastics and ECs still needs to be considered. This work highlights the link between microplastics with associated ECs ingested by aquatic organisms and the human health risk of consuming polluted seafood.

Characterization of microplastic contamination and influencing factors in different environmental compartments of a coal mining subsidence area in northern Anhui, China

Environmental pollution caused by microplastics (MPs) has garnered significant global attention, however, research on MPs contamination of various environmental compartments within mining regions remains limited. The objective of this study was to investigate the occurrence and distribution of MPs in soil, surface water, and sediment, as well as the factors influencing the distribution of microplastics in the Panji Mining Area in Huainan City, Anhui Province, China. The findings indicate that MPs contamination in soil and surface water within the study area is substantial. The average abundance of MPs in soil, surface water, and sediment were 1860.8 n·kg−1, 11,323.7 n·m−3, and 384.0 n·kg−1, respectively. The dominant MPs were transparent, fibrous particles <0.1 mm, with polyethylene (PE) common in soil and polypropylene (PP) prevalent in surface water and sediment. A significant correlation was observed among MPs and environmental factors such as pH, total phosphorus (TP), and total organic carbon (TOC) (p < 0.05) showed a positive correlation in soil while in sediment, MPs abundance showed a positive correlation with pH and TOC (p < 0.05). Additionally, a positive correlation was observed of MPs abundance with pH, total nitrogen (TN), and nitrate nitrogen (NO₃−-N) (p < 0.05) in surface water. This study provides insights into the characteristics, distribution, and environmental risks of MPs in mining areas, laying a foundation for the development of prevention and control strategies to mitigate MPs pollution in these regions.

Occurrence and visual characterization of microplastics from Mahakam River at Tenggarong City, Indonesia

Indonesia generates approximately 7.8 million tons of plastic waste annually, which 4.9 million tons is mismanaged. Presently, there is significant concern on microplastics (MPs) pollution in aquatic environment. The research on the prevalence of MPs in river systems are comparatively lower than the studies conducted on marine systems. The primary goal of this research was to look into the prevalence of MPs in the river water of Mahakam of Tenggarong City, Indonesia. To adequately represent this area, a meticulous selection method was used to find five separate sampling locations, with two stations at each location, positioned 200 m apart on opposite sides of the river. According to the study's findings, MPs has been observed in the range of 19.2 ± 1.8 to 58.5 ± 3.5 particles/l. Based on the MPs type, fragments (43.4 %) were the most common type of MPs found in water samples. Furthermore, 44.6 % of the MPs had size smaller than 1000 μm. The prevalent hues observed in the water samples were transparent and black, composing 75.6 % of overall formation. The determination of microplastic polymers employed Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy, revealing the presence of various type, such as polyethylene (PE) and polypropylene (PP).

Occurrence and spatial distribution of microplastics in water and sediments of Hatiya Island, Bangladesh and their risk assessment

This research has evaluated the MPs distribution, characteristics, and potential threats of MPs in surface water and sediments from Hatiya Island. The results showed that the abundance of MPs was 139 ± 44 items/m3 in surface water and 493 ± 80 items/kg dw in sediments, indicating higher levels of MPs contamination in sediment samples. Fibers were the predominant kind of microplastics, and microscopic sizes (0.3–1.5 mm) MPs were generally more frequent and largely present in both the surface water and sediments. Fourier-transform infrared spectroscopy (FTIR) confirmed that polyethylene terephthalate was the major polymer component of microplastics in surface water, whereas polyethylene was the most abundant polymer in sediments. MPs contamination risk was examined based on multiple risk assessment models. Nemerow pollution index (NPI) and pollutant load index (PLI) show minimal pollution levels of MPs. But potential hazard index (PHI), potential ecological risk factor (Er), and potential ecological risk index (RI), indicate severe MPs contamination due to the presence of polyurethane, polycarbonate, polyvinyl chloride, epoxy that were hazardous MPs and exhibited a critical concern for MPs risk. These statistics will help to understand the environmental difficulties generated by MPs and which hazard is waiting for mankind in the future.

An overview on the characterization of microplastics (MPs) in waste water treatment plants (WWTPs)

The occurrence of microplastics (MPs) in the environment has become an emerging global concern and has been reported to pose consequential risks to organisms, human health and the environment. Due to their small size (ranging from 1 μm to 5 mm in size), eliminating MPs from wastewater poses a significant challenge, which leads to their accumulation in wastewater treatment plants (WWTPs). This review article explores the method of characterizing MPs in WWTPs to understand their environmental impact better. It also discusses various techniques for characterising MPs in WWTPs, drawing on existing scientific literature. The article provides a comprehensive review of the current methodologies used for the characterisation (chemical, morphology, thermal) of MPs in WWTPs. Furthermore, analytical techniques such as scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy are discussed along with their limitations and potential for recognition and differentiation of various kinds of MPs. The article also highlights the need for standardisation of sampling, extraction, and analytical methods to ensure comparability of results from different studies. The review identifies several obstacles in characterising MPs within WWTPs, such as the absence of standardised methods, restricted detection thresholds, and challenges in quantifying MPs within intricate environmental contexts. To overcome these obstacles, the review recommends prioritising research efforts aimed at enhancing current methodologies, emphasising the need to refine techniques for better comprehension and analysis of MPs within WWTPs.

Microplastic Pollution in Riparian Soils of the Rapidly Growing City of Thimphu, Bhutan

Plastic has become a vitally important material for humans; however, the large amount of plastic waste generated annually pollutes the environment. Plastic decomposition generates microplastics (MPs), which have emerged as a concerning global environmental pollutant because of their potential to be more harmful to the environment than their larger counterparts. This study examined the occurrence and abundance of MPs in riparian soils (RS) of a rapidly growing city in Thimphu, Bhutan. Additionally, the study investigated the relationships between the abundance of MP and several variables, such as the physicochemical properties of the soil, land use, the distance to impervious cover (IC), the plot IC%, surface plastic, textile waste, and the distance to upstream drainage outlets within the riparian zone (RZ). A density separation technique was used to extract MPs. The results showed that RS in urban sites had higher concentrations of MPs (93.3%) than in other land use (7.7%, p = 0.04). Blue MPs (46.2%) were the most common plastic colour. In urban RS, MPs ranged from 0 to 500 particles/kg. MP concentration showed a positive correlation with available phosphorus (p = 0.01) and the distance to the upstream drainage outlets (p = 0.01). Our findings highlight the nature and pathways of MP pollution in rapidly growing cities, where economic growth often overshadows environmental management. We also identify opportunities for these cities to mitigate MP pollution by reclaiming surface plastic and textile waste, stepping up recycling initiatives, and disposing of plastic-ridden waste in low-impact landfills.

Microplastics in Urban Soils From Different Land Use Activities of Cyberjaya (Malaysia): Exploring Occurrence, Relationships, Sources and Pollution Level

ABSTRACTAs human activities continue to increase, the production and utilisation of plastics have become pervasive, leading to a surplus of plastic waste in the environment. This has turned the terrestrial ecosystem, encompassing soil, into a significant receptacle for the growing accumulation and discharge of plastic waste. Thus, the objective of this study is to investigate the occurrence, relationships, sources and pollution levels of microplastics in urban soils from different land use activities in Cyberjaya, Malaysia. Surface soil samples were collected from land uses (i.e., vacant areas, residential areas, commercial areas, construction areas and roadways). These surface soil samples were analysed for microplastic occurrence using density separation, microscopy and spectroscopy methods. The microplastics particles were analysed for size, colour and shape. Selected microplastics particles were also analysed for its plastics polymers using Fourier‐Transform Infrared Spectroscopy. Microplastics occurrence ranged from 0.3 to 1.5 particle/kg, with the highest average occurrence in the construction area (0.69 particle/kg) and lowest in the vacant area (0.33 particle/kg). Microplastics particle size was shortest in commercial areas (586.08 μm) and longest in vacant areas (793.78 μm). There were no similarities between microplastics occurrence and particle size across these different land use activities, suggesting that the microplastics occurrence in urban soils depends on external disturbances during each land use activity. Significant correlation between microplastic particle size and temperature (r 2 = 0.517) showed that each land use activity is influenced by external disturbances. The I geo values showed that the microplastics pollution level in urban soils is classified as uncontaminated to moderately contaminated. Microplastic particles in urban soils were found in various shapes (i.e., fragments, films and fibres) and colours (i.e., transparent, grey, blue, red, green, purple, black, white and yellow) along with plastic polymer types (i.e., ABS, PET, PP, PE and PS) due to traffic volume, tyre wear, mismanaged plastic waste and degradation rate. This study highlights the need for pollution management and waste disposal to avoid urban environmental problems and adverse health effects.

Microplastics contamination through a mighty estuarine island: Distribution, influencing factors, and risk assessment

The global concern over microplastic (MP) contamination in diverse ecosystems is well-established, yet Nijhum Dwip Island (NDI), known for its ecological diversity, has not undergone a comprehensive study addressing the extent of MP pollution. This research aims to evaluate the spatial distribution, influencing factors, and ecological risks of MPs in both sediment and surface water surrounding NDI, situated in the Northern Bay of Bengal. A meticulous collection of 40 sediment and 40 tidal water samples from various sites facilitated a detailed analysis. The mean abundance of MPs in sediment was 138.39 ± 34.15 pieces/kg, while in water, it was 72.83 ± 30.76 pieces/m³. Various shapes observed on NDI included films, fragments, fibers, and foams, with fragments dominating in sediment (64.05 %) and water (61.51 %). Analysis of FTIR spectra identified two primary polymer types, namely polyethylene (PE) at 57 % and polypropylene (PP) at 40 %. The results indicated elevated pollution levels on NDI, with sediment and water pollution load index measuring 1.32 and 2.01, respectively, signifying significant MP contamination in both compartments. Given the island's rare biodiversity, the vicinity of wastewater sewages, anthropogenic activities, and atmospheric deposition, could be behind MP contamination in water and sediments. No strong correlation between MP and physiochemical properties in water and PCA biplots showed their similar distribution, whereas MP abundances in sediment were significantly correlated with pH and organic matter (p<0.05), signifying a pivotal role in transporting MPs in the aquatic environment. Two canonical variables were identified as important by canonical correlation analysis, demonstrating the interdependence of MP contamination at the sample sites. This research contributes to better insights into the occurrence of MP in the rare islands, which are ecosystems that have been hardly examined for this type of pollution, and it can report sustainable interventions to lessen MP inputs to the Bay of Bengal.