Microplastics In Water Samples Research Articles

Microplastics in freshwater lakes: A case study from Southern India

Microplastics (MP) are prevalent and virtually present in all environmental domains. Though microplastics are reported worldwide, only limited studies have been carried out in freshwater ecosystems. Therefore, this study was initiated to evaluate the presence of microplastics in a freshwater lake (Vellayani Lake), located in Thiruvananthapuram, Kerala, South India. The water quality of this lake assumes significance as it serves as a primary drinking water source for thousands of people in Thiruvananthapuram. This study analyzed the seasonal distribution of microplastics in water samples from three locations within Vellayani Lake under two distinct climatic conditions, identifying microplastics in all sampled locations. During the monsoon sampling, the abundance of MP ranged from 20 to 100 particles/m3, with an average abundance of 65 particles/m3 and a total abundance of 194 particles/m3. However, during the summer, microplastic concentrations ranged from 34 to 67 particles/m³, with an average abundance of 49 particles/m³ and a total abundance of 147 particles/m³. Four varieties of polymers, High-Density Polyethylene (HDPE), Low-Density Polyethylene (LDPE), Polypropylene (PP), and Polyethylene Terephthalate (PET), have been detected. HDPE is the most abundant polymer in the water, along with PP, PET, and LDPE. The dominance of Polyethylene and Polypropylene polymers in the lake water samples highlights the rapid disintegration of single-use disposable plastics. The consumption of microplastics has been proven to be harmful, and their long residence time and widespread presence in the water make it necessary to develop new purification techniques to specifically target plastic contaminants.

Study of Advanced Techniques for Inquisition, Segregation and Removal of Microplastics from Water Streams: Current Insights and Future Directions

The present research covers different analytical methods utilized for the diagnosis and characterization of microplastics (MPs) in water and wastewater, such as particle size distribution analysis, and focuses on the sources and forms of MPs in receiving environments. First, we look at the most recent collection techniques, which include a variety of spectroscopic, chromatographic, and microscopic approaches used to identify and measure microplastics in water samples. We then investigate separation techniques designed to separate microplastics from diverse environmental matrices. This involves applying existing methods of separation based on density, such as centrifugation, flotation, and sedimentation, as well as more recent ones, like the use of microfluidic devices and materials for selective adsorption. Lastly, we look into removal methods aimed to reduce the buildup of microplastics in aquatic environments. These include enzymatic breakdown, coagulation/flocculation, and filtering, among other physical, chemical, and biological techniques.

Microplastics, their abundance, and distribution in water and sediments in North Chennai, India: An assessment of pollution risk and human health impacts

Plastic particles, measuring <5 mm in size, mainly originate from larger plastic debris undergoing degradation, fragmenting into even smaller fragments. The goal was to analyze the spatial diversity and polymer composition of microplastics (MPs) in North Chennai, South India, aiming to evaluate their prevalence and features like composition, dimensions, color, and shape. In 60 sediment samples, a combined count of 1589 particles were detected, averaging 26 particles per 5 g−1 of dry sediment. The water samples from the North Chennai vicinity encompassed a sum of 1588 particles across 71 samples, with an average of 22 items/L. The majority of MPs ranged in size from 1 mm to 500 μm. The ATR-FTIR results identified the predominant types of MPs as polystyrene, polyvinyl chloride, polyethylene, polyethylene terephthalate, and polypropylene in sediment and water. The spatial variation analysis revealed high MPs concentration in landfill sites, areas with dense populations, and popular tourist destinations. The pollution load index in water demonstrated that MPs had contaminated all stations. Upon evaluating the polymeric and pollution risks, it was evident that they ranged from 5.13 to 430.15 and 2.83 to 15,963.2, which is relatively low to exceedingly high levels. As the quantity of MPs and hazardous polymers increased, the level of pollution and corresponding risks also escalated significantly. The existence of MPs in lake water, as opposed to open well water, could potentially pose a cancer risk for both children and adults who consume it. Detecting MPs in water samples highlights the significance of implementing precautionary actions to alleviate the potential health hazards they create.

Occurrence of Microplastics in Kemena River and Niah River of Sarawak, Malaysia

Microplastics in freshwater have been identified as a significant contributor to plastic pollution in marine environments. However, the effect of urbanization on the quantity and spatial dispersion of microplastics in freshwater ecosystems of Sarawak and Malaysia remains unclear. The primary objectives of this study are to investigate the quantity and distribution of microplastics in water and riverbank sediments, as well as to analyze the properties of microplastic particles in the Kemena and Niah rivers. The selection of these rivers was based on the presence of commercial, residential, and industrial areas along their lengths. A total of 24 water and soil sediment samples were collected from three different sites along the Kemena and Niah rivers. The concentration of microplastics in water samples ranged from 60 to 128 items per liter, while sediment samples ranged from 46 to 76 items per liter. The sediment samples also contained microplastics ranging from 21 to 40 and 45 to 125 items per kilogram. Microplastics were observed in various forms, including fibers, films, foam, and fragments, in both water and soil sediment samples. The majority of microplastics were between 0.1 and 1 mm in size, with blue being the most common color observed in river water and transparent in sediment samples. The ATR-FTIR spectrum analysis indicated the presence of four distinct polymers: polyethylene (PE), polystyrene (PS), polycarbonate (PC), and polyethylene terephthalate (PET). This study provides valuable information on the abundance, distribution, chemical composition, and physical properties of microplastics in the Kemena and Niah rivers.

Using optimized particle imaging of micro-Raman to characterize microplastics in water samples

Characterizing the chemical properties, morphologies, size, and quantities of microplastics (MPs) in water samples with high precision is critically important for understanding the environmental behaviors of MPs. Traditional detection methods, such as Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy point-by-point detection, provide worthy reference techniques but are time- and labor-consuming. We established a super time-saving and high-precision technique to characterize MPs using micro-Raman automatic particle identification (MR-API). Based on the identification of PS spheres, screen magnification, exposure time, and the number of scans are selected as crucial detection parameters for MR-API analysis, which highly affect the precision of the results. Detecting particles down to 1 μm requires magnification of the mosaic until the scale showed 200 μm. The recommended setting parameters were 83.33 or 100 ms exposure time, 20 scans, 7 mW laser power, and 1 μm image pixel size, suitable for polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), polyethylene (PE), polyvinyl chloride (PVC), and polyamide (PA) particles detection. With the complete procedure of MR-API measurements, the recovery of MPs was 61.67–90.00 %. To validate the feasibility of the MR-API, the method was used to detect samples of known plastic types (mask leachates) and unknown plastic types (urban lake). A total of 4540 particles in the sample of mask leachates consuming 35 h 50 min 43 s, and 0.92 ± 0.49 % of particles were identified as MPs. The urban river sample efficiently identified PP, PET, PE, PVC, PS, EVA, and VC/VAC MPs using this method. The detected MPs size ranged from 8.3 to 5000 μm, saving 75.03 % and 58.38 % of the time compared to the conventional micro-FTIR and micro-Raman point-by-point methods, respectively. Therefore, this method is effective for detecting MPs in the environmental samples and has excellent prospects.

Occurrence and characteristics of microplastics in surface water and sediment of Zayandeh-rud river, Iran

Background: Zayandeh-rud river is the most important river in the central regions of Iran and the present study aimed to provide new insights into microplastics (MPs) pollution in surface water and sediments of this river. Methods: Water and sediment samples were collected in July 2021 from 19 sampling sites along the river. Organics matters were removed from the samples by wet peroxide oxidation (WPO), and MPs were extracted by floatation in ZnCl2 -saturated salt and filtration on a polytetrafluoroethylene (PTFE) membrane filter. Trapped MPs on the filter were counted and qualified by a stereomicroscope. Results: MPs were found in 13 sites from 19 sampling sites along the river. The minimum and maximum levels of MPs in water samples were 0 and 51±16.5 particles/m3 , respectively. MPs also were detected in the sediments of all sampling sites except the first two sampling sites (the maximum level was 58±25.9 particles/kg as dry sediment). Fragments were the most common shape of MPs in both water and sediment samples. 72.3% of MPs detected in water samples were 1-5 mm in size, while this percentage for sediment was 49.2%. The five main polymer types found in water and sediment samples were polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC). Conclusion: These levels of MPs in the water and sediments of Zayandeh-rud river and longtime persistence of plastics in the environment is a significant threat to environmental and human health and need serious attention to restrict MPs release into the river.

Comparision protocols for extraction of microplastics in water samples

Microplastics (MPs) are increasingly recognized as emerging pollutants in various environmental components. However, protocols for sampling, analysis, and standardization of measurements in MPs research are still under development. The extraction method is a crucial factor that affects the accuracy and comparability of microplastic abundance data. In this study, we evaluated and compared the effectiveness of four different extraction protocols (D, MJ, MA, and S) for separating MPs from water samples of different types (brackish, marine, and river water). Known combinations of MP particles (polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS), and polyvinyl chloride (PVC)) with sizes ranging between 150 μm and 700 μm were spiked into water samples. Our results showed that the average recovery efficiency of microplastics using the four studied methods ranged from 53% to 86%. Notably, the recovery efficiency of light-density MPs was higher than that of heavy-density MPs. For purified water samples (PW) obtained from a filtration system, only H2O2 was effective in recovering MPs with an efficiency of 80 ± 6.61%. The S method for MP extraction, which combines SDS, Bioenzyme, H2O2 30%, and a saturated salt solution using NaCl, gave the highest average MP recovery of 78.13 ± 2.39% in PW and 69.72 ± 4.81% in surface water. This method has several advantages over the other three methods, such as low cost, environmental friendliness, and compatibility with various water samples, making it suitable for analyzing large amounts of MPs. Our study highlights the importance of carefully selecting the appropriate extraction protocol for accurate and reliable microplastic analysis in different water samples.

Human health risk perspective study on characterization, quantification and spatial distribution of microplastics in surface water, groundwater and coastal sediments of thickly populated Chennai coast of South India

Microplastics (MPs) are defined as plastic particles smaller than 5 mm in size. They are primarily derived from larger pieces of plastic debris that degrade into smaller pieces. The current study identified, characterized, and quantified MPs in Chennai coast coastal aquifers, seawater, and foreshore sediments. The spatial distribution and polymer composition of MP particles were studied to identify and evaluate their abundance and characteristics (composite, size, color, and shape of MPs). The foreshore and river mouth sediment samples were found to be contaminated by MPs with a total of 263 particles in 12 samples collected from different locations (average of 22 particles 5 g−1 of dry sediment (d.s.)). The surface water and groundwater samples were also contaminated by MPs with a total of 315 particles in 25 samples collected from different locations (average of 13 particles/L). Size of majorities of MPs ranged from 1 mm to 300 μm. The study also confirmed the presence of MPs in sediments and water samples collected from the study area using Fourier transform infrared spectroscopy (FTIR). FTIR results revealed that nylon, polyvinylchloride, and polyethylene terephthalate were the predominant types of MPs. The spatial variation map showed that high concentration of MPs was observed on tourist beaches. Remediation technologies are highly effective in eliminating and preventing MPs pollution in our environment. The existence of MPs in water samples suggests that it is essential to take preventive steps to avoid MPs causing health issues like neurotoxicity, Alzheimer, and cancer.

Investigating the pollution of bottled water by the microplastics (MPs): the effects of mechanical stress, sunlight exposure, and freezing on MPs release.

Bottled water is becoming more popular worldwide and possible contamination's need to be analyzed. Microplastics (MPs) are ubiquitous environmental pollutants and have recently been regarded as an important contaminant in bottled water due to oral intake and possible threats to human health. In the present study, MP amounts in 23 popular Iranian brands of bottled water were determined by filtration and counting under scanning electron microscopy (SEM). The effects of mechanical stress, environmental factors, and freezing on MP release also were investigated. The average amounts of MPs in water samples were 1496.7 ± 1452.2 particles/L (199.8 to 6626.7 particles/L). The amounts of MPs in different brands was significantly different (p < 0.05). As much as 91.3% of detected particles had the size between 1 and 10μm. The most likely polymers determined by FTIR spectroscopy was polyethylene terephthalate (PET). The freezing of water in the bottles did not show any significant effect on the MPs release, but mechanical stress to the bottles increased MP amounts in the water significantly. Environmental factors including sunlight exposure and the age of bottles showed the most degradative effects on the structure of polymers in the body of PET bottles and release of MPs. Regardless of their type, source and commercial brands, bottled water is contaminated with hundreds to thousands MPs/L. The main portion (above 90%) of these MPs are < 5μm particles with considerable effects on human health.

Determination of microplastics in pond water

Plastics in the form of the fibers, fragments or beads, smaller than 5 mm in size, are of increasing concern. These are called as the microplastics. Microplastics is considered generalized pollutant that is present in practically all environmental compartments, especially in the marine and freshwater environment. Microplastics pollution has not been studied much for Indian aquatic systems like ponds in urban areas. In this study, we present the assessment of microplastics pollution in Vadodara’s Gotri pond water. Using standard method of density separation, we have isolated and characterized microplastics in water samples collected from the pond. The study shows for the first time presence of microplastics pollution in ponds in the city, with the amount ranging from 0.010 mg to 0.039 mg per liter. The isolated microplastics were characterized using FTIR spectroscopy, based on the identification of functional groups in the material.

A New Optical Method for Quantitative Detection of Microplastics in Water Based on Real-Time Fluorescence Analysis

Microplastics (MPs) have recently emerged as a new major and ubiquitous environmental pollutant with still undefined, yet potentially high risks for human health and ecosystems. This has prompted growing public concern along with an increasing number of scientific studies. In particular, recent research has highlighted the need for a standardized methodology to monitor microplastics in different media, particularly in water. This study reports on the use of a new particle counter for the quantitative detection of MPs in water samples based on real-time analysis of fluorescence emissions. The instrument was calibrated using two types of plastic particles, i.e., polyvinyl chloride and high-density polyethylene, selected as examples of high- and low-density plastics, respectively. Specific solvents were used to match the different plastic densities. Measurements were also carried out on particles obtained from wastewater samples collected at the inlet and outlet of specific units of a municipal wastewater treatment plant after sieving, filtering, digestion with hydrogen peroxide to remove degradable organic matter and resuspension in the solvents employed during the calibration step. A Fourier transform infrared spectroscopy analysis performed on the same wastewater samples confirmed the presence of MPs, and, in particular, of polyethylene, in some of the samples in which the highest concentrations were measured applying the proposed method. Therefore, the novel particle counter described in this paper could represent a promising method to quantitatively measure MP concentrations in water samples.

Visualizing undyed microplastic particles and fibers with plasmon-enhanced fluorescence

Despite widespread awareness that enormous consumption of plastics is not sustainable, the global production and use of plastics continue to grow. This generates vast amounts of plastic waste and microplastics, ending up e.g., in the marine environment. There are serious challenges in detecting and measuring microplastics, especially in highly diluted natural samples. Here, a new alternative microplastic detection method based on plasmon-enhanced fluorescence (PEF) was developed and tested using fluorescence microscopy. In particular, gold nanopillar-based substrates, displaying (i) high electromagnetic field enhancement, and (ii) surface superhydrophobicity and high adhesion properties, were utilized to enhance the fluorescence emission signal from microplastics in water samples. The fluorescence microscopy imaging revealed remarkable fluorescence enhancement by the PEF substrates on the microplastic particles and fibers with different sizes of both conventional, low-density polyethylene, and biodegradable poly (butylene adipate-co-terephthalate). The limit of detection and quantification by this method was estimated to be as low as 0.35 and 1.2 femtograms, respectively. The observed fluorescence enhancement of the gold nanopillar substrates for the microplastics was ca. 70 times greater than the case of having the microplastics on a glass substrate. Additionally, 3D FEM simulations were performed to further investigate the system's electromagnetic field distribution near the nanostructures. This new method makes undyed microplastics visible in fluorescence microscopy, even particles and fibres too small to be imaged with conventional light microscopy. This can be a great tool for microplastic research, helping us to detect, study, understand microplastic dynamics in water based systems.

Microplastic ingestion in zooplankton from the Fram Strait in the Arctic

Some of the highest microplastic concentrations in marine environments have been reported from the Fram Strait in the Arctic. This region supports a diverse ecosystem dependent on high concentrations of zooplankton at the base of the food web. Zooplankton samples were collected during research cruises using Bongo and MOCNESS nets in the boreal summers of 2018 and 2019. Using FTIR scanning spectroscopy in combination with an automated polymer identification approach, we show that all five species of Arctic zooplankton investigated had ingested microplastics. Amphipod species, found in surface waters or closely associated with sea ice, had ingested significantly more microplastic per individual (Themisto libellula: 1.8, Themisto abyssorrum: 1, Apherusa glacialis: 1) than copepod species (Calanus hyperboreus: 0.21, Calanus glacialis/finmarchicus: 0.01). The majority of microplastics ingested were below 50 μm in size, all were fragments and several different polymer types were present. We quantified microplastics in water samples collected at six of the same stations as the Calanus using an underway sampling system (inlet at 6.5 m water depth). Fragments of several polymer types and anthropogenic cellulosic fibres were present, with an average concentration of 7 microplastic particles (MP) L−1 (0–18.5 MP L−1). In comparison to the water samples, those microplastics found ingested by zooplankton were significantly smaller, highlighting that the smaller-sized microplastics were being selected for by the zooplankton. High levels of microplastic ingestion in zooplankton have been associated with negative effects on growth, development, and fecundity. As Arctic zooplankton only have a short window of biological productivity, any negative effect could have broad consequences. As global plastic consumption continues to increase and climate change continues to reduce sea ice cover, releasing ice-bound microplastics and leaving ice free areas open to exploitation, the Arctic could be exposed to further plastic pollution which could place additional strain on this fragile ecosystem.

Impact of Microplastics in Day to Day Life

Manmade synthetic products like plastics were originally invented for comfort as they were inexpensive, lightweight, durable and hydrophobic but in the long run they posed to be non degradable causing air, water and soil pollution. With mechanical degradation, chemical degradation, exposure to UV radiations and even biological degradation by certain microorganisms, plastics are converted to micro-plastics. The increase of certain factors like increased levels of pollution and greenhouse gasses are depleting the Ozone layer. Leading to increased temperature and ambient humidity the degradation potential of plastic polymers by UV- B radiations increases. Micro-plastics including polyethylene terephthalate, polyethylene, polystyrene, polypropylene, polyvinyl chloride were determined in bottled water. With the increasing use of plastics in day-to-day life, microplastics are leaching out into environment. After leaching out in the environment these microplastics are entering into food web, causing lot of threats to living organisms. For detection of microplastics in water samples, dyes like Rose Bengal and Nile Red are being used for making better contrast under microscopy. Now a day’s use of techniques like Pyrolysis-GC/MS, micro Raman spectroscopy, and IR/FTIR spectroscopy has made the detection of microplastics an easy task. Microplastics entering the food chain are usually inert in nature possessing different sizes and shapes. These microplastics when enter into a cell or tissue cause mechanical damage to them. Microplastics induce inflammation, disturbs metabolism and even lead to necrosis of cells and tissues. The objective of this publication is to present and discuss sources, identification and toxicological impact of microplastics in drinking water.

Microplastic contamination assessment in water and economic fishes in different trophic guilds from an urban water supply reservoir after flooding

Rain and floods events are responsible for the transport of microplastics in freshwater ecosystems, yet to date, rare study has examined microplastics pollution in urban water supply reservoirs during such events. In this study, we investigated the concentrations and characteristics of microplastic in water and economic fish species with different feeding guilds in the Dafangying Reservoir, an important source of drinking water for Hefei city. Microplastic concentrations in water were relatively higher than that in natural lakes, indicating abundant microplastic contaminants input through overland runoff triggered by flooding. Our results detected five types (fiber, debris, film, microbead and particle) and six colors (black, transparent, blue, yellow, red and green) of microplastics in water samples. Fiber accounted for the dominant shape, which may result from the household sewage from washing clothes and desquamated fiber transported by wind and overland runoff. Meanwhile, transparent was the predominant microplastic color, which can be ascribe to the widely use of intentionally manufactured transparent disposable plastic commodities in cities. Then in fish samples, the microplastic concentrations ranged from 8.75 to 51.3 items/individual in fish guts, and 9.5–52.6 items/individual in fish gills. Our results demonstrated significant higher microplastic concentrations in planktivorous and herbivorous species. The filter feeding capture mode, i.e., engulfing floating prey through frequently drawing in large volume of water confused with microplastics, may result in the higher microplastic concentrations of planktivorous fishes. Due to the dense microplastics adhering on plant surface, herbivorous fishes can concentrate higher microplastics abundance through the ingestion of macrophytes. According to the biological concentration factor (BCF), all the determined microplastics gave BCF far below 1, suggesting the low bioaccumulation capacity of microplastics in fish species.

Investigation of microplastics in edible wild mussels from İzmir Bay (Aegean Sea, Western Turkey): A risk assessment for the consumers

The presence of microplastics (MPs) was determined in Mediterranean mussel (Mytilus galloprovincialis Lamarck, 1819) and grooved carpet shell (Ruditapes decussatus Linnaeus, 1758) together with water samples from in İzmir Bay (Aegean Sea, Western Turkey). A total of 895 MPs from Karşıyaka (Station 1), and 787 MPs from Gülbahçe (Station 2) were detected in 60 mussel samples, giving a total content of 1682 MPs. In water samples, a total of 545 MPs were detected in samples from Station 1 and 1287 MPs in samples from Station 2 (1832 MPs total). The amount of MPs in water samples was less in Station 1 than in Station 2. This difference is probably caused by Çiğli Wastewater Treatment Plant (WWTP) located near Station 1. Public health risk assessment on the consumption of the species M. galloprovincialis revealed that 70.82 items person−1 year−1 MPs through this species could enter consumers' digestive systems.

Microplastic pollution characteristic in surface water and freshwater fish of Gehu Lake, 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.

Microplastic pollution in Yellow River, China: Current status and research progress of biotoxicological effects

This study aims to comprehensively assess the environmental risks of microplastics in the Yellow River, achieving the following results through comprehensive research. The average microplastic abundances in the river waters and sediments are 5358–654000 n/m3 and 43.57–615 items/kg, respectively, and there are fewer microplastics in water samples than in sediments. Microplastics in the study area can be divided into five types according to their occurrence morphologies, namely fragments, foams, films, fibers, and particles. The most widely distributed pollution types in sediments include debris, fibers, and particles. In contrast, fibers are the dominant type in water samples, accounting for 68.18% –98.93%. The chemical components of the microplastics include polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyvinyl chloride. The microplastics are in four colors, with white accounting for a higher proportion. The grain size of the microplastics in tributaries or lakes of the Yellow River is less than 2 mm, which makes them liable to enter organisms for enrichment. Furthermore, the sources of the microplastics are closely related to agricultural and industrial production and biological activities in habitats and exhibit seasonal and hydrological characteristics. The microplastics in the study area show the adsorption of metals and nonmetals to different degrees, which increases the pollution risks of heavy metals combined with microplastics. In addition, microplastics can accumulate in organisms in the Yellow River and cause physical, biochemical, and other damage to aquatic organisms, thus further posing carcinogenic risks to human beings. Therefore, it is necessary to study, monitor, and control the pollution and effects of microplastics in the Yellow River, in order to provide theoretical references for the control of pollution and ecological risk of microplastics in the river.©2021 China Geology Editorial Office.

The abundance and characteristics of microplastics in rainwater pipelines in Wuhan, China

Urban rainwater runoff is considered to be an important way to transport microplastics into the freshwater. By analyzing the microplastics in rainwater pipelines in different land function areas in Hongshan District (Wuhan, China), the preliminary results of microplastics abundance and characteristics in rainwater pipelines and rainwater pipeline sediments were obtained. The microplastics abundance in water samples was 2.75 ± 0.76 to 19.04 ± 2.96 items/L, the abundance of microplastics in the sediment was 6.00 ± 1.63 to 27.33 ± 4.64 items/100 g. The highest abundance among the samples was in the business district and the lowest in the campus. The microplastics in water samples and sediment samples were mainly fragments, accounting for 44.7% and 57.1%, respectively. The proportion of particle size <1 mm was 75.0% and above. The color of microplastics was diversified, and colored particles occupied over 60.0%. The types of polymers detected were mainly polyethylene, polypropylene and polyester, which were related to the types of polymers widely used in life. This study shows that urban rainwater pipelines is one of the ways for land-based microplastics to migrate to freshwater, and the accumulation of microplastics in stormwater pipe sediments might be an important contributor to microplastics in freshwater area.

Accumulation and distribution of microplastics in the sediment and coastal water samples of Chabahar Bay in the Oman Sea, Iran

Frequency, distribution, color, and types of microplastics (<5 mm) in water and sediment of Chabahar Bay in southeastern Iran was investigated in 10 stations. Density of microplastics in water samples was between 86 and 362 particles/L (average density 218 ± 17 particle/L). In the sediment, microplastic density was between 112 and 468 particles/L (average density of 262 ± 17 particle/kg). The highest concentrations of microplastics were in stations adjacent to urban, commercial, recreational, and fishing sites. The most abundant forms in surface water and sediment were fragments (42.34%) and fibers (32.22%). Highest frequency colors were black, transparent, and white, respectively. A fourier transform infrared (FT-IR) spectrometer was used to determine micro plastic composition. Polyethylene, polyethylene terephthalate and nylon were detected. Polyethylene, a common packaging material made up 38% of the total polymers. Polyethylene terephthalate, used in clothing, liquid and food containers was found at 29% of the total microplastics.