Abundance Of Microplastics In Water Research Articles

Microplastic Abundance in The Waters of The Middle Section of The Citarum River, Karawang, West Java

Microplastics in the Central Citarum River, Karawang, West Java, originate from anthropogenic activities of people living around the watershed, which is an industrial, agricultural, and densely populated residential area. Microplastics are degraded plastics < 5 mm in size. This study aims to determine the abundance and size of microplastics in the Middle Citarum River, through observation with a microscope. Sampling was conducted at three locations with three observations: February, March, and April 2022. The types of microplastics found were pellets, films, fibers, and fragments. Microplastic particle size < 0.3 mm was the most common size found. The abundance of microplastics in the water of the Middle section of the Citarum River is different at each sampling location. The total number of microplastic particles in all research locations was 4,413 particles. The highest abundance of microplastics in all sampling locations was in densely populated residential areas at 239.7 ± 326.7 particles/m3 , followed by agricultural areas with an abundance of 72.5 ± 63.8 particles/m3 , then the lowest abundance was in industrial areas at 55.6 ± 57.8 particles/m3. The average abundance of microplastics in the middle Citarum River water was 122.6 ± 209.7 particles/m3. Statistical analysis using Kruskall Wallis with a df value of 2 > 0.05 showed no significant difference in microplastic abundance at each research location. All stations had the same potential for microplastic pollution. This study shows that high anthropogenic activities lead to high microplastic pollution in water. Therefore, proper mitigation and management of waste and plastic waste are needed.

Fate and distribution of microplastics in water and sediment collected from Samiran ditch irrigation

AbstractDitch irrigation is an important route that potentially discharges microplastics (MPs) into environment. Samiran ditch irrigation is the largest urban irrigation in Pamekasan City, Indonesia. Water and sediment samples were collected in Samiran ditch irrigation to identify MPs including their color, shape, size, and number of MPs. From all sampling locations, MPs were found in both the water and sediments of the Samiran ditch irrigation with sizes ranging from 0.1 mm to 2.9 mm. The abundance of MPs in water ranged from 0.5 to 0.9 items/L, while MPs in sediments 0.14 to 0.23 items/g with colors of black, blue, and yellow. The polymer types of polyethyleneimine (PEI) and polypropylene (PP) were found both in surface water and sediment sample. MPs such as fragments, filament, fiber, and pellet were found in Samiran ditch irrigation with fiber was dominant found in the surface water (40%) and fragment was dominant in sediment (25%).

Occurrence and distribution of microplastics in the adjacent environment of Yellow River Delta, China

In the precent study, the microplastics (MPs) pollution level was evaluated in diverse environmental samples from the Yellow River Delta. The results indicated that the abundance of MPs in water, sediment and soil samples ranged from 0.50 to 7.83 items·L−1, 200 to 4200 items·kg−1, and 100 to 1400 items·kg−1, respectively. Film form of MPs was dominant in water, while fiber MPs were dominant in both sediment and soil samples. In all samples, most MPs were < 1 mm in size. White was the main color in water, black was the main color in sediment and soil samples. The most common MPs type was polyethylene (33 %) in water, while rayon accounted for the majority of MPs in sediment (42 %) and soil (70 %) samples. The redundancy analysis results showed that MPs in water and sediment were more affected by water quality, while soil MPs were easily affected by landscape pattern.

Seasonal Variation Analysis of Microplastic Distribution in the Estuary of Brantas River

Every year, 0.48-1.29 million tonnes of plastic waste is estimated to enter the waters due to poor plastic waste management in Indonesia. Plastic waste has the potential to be degraded into smaller particles through ultraviolet (UV) radiation, weathering process, water currents, physical-mechanical and biodegradation. Plastics with particle sizes between &gt;1 μm and &lt;5 are categorized as microplastics (MP). Microplastic particles are mainly distributed in surface waters. Rivers are considered as the main route of plastic transportation from the land to the ocean. The Brantas River in Surabaya is the main downstream section of the Brantas River and plays an important role in providing clean water for Surabaya City, aquatic biota habitat, and irrigation. With extreme weather conditions such as long dry seasons and high rainfall in the rainy season distribution and abundance of microplastics in water bodies/rivers tend to vary. The study's goal is to determine the effect of seasonal water volume (dry and rainy) on the abundance and characteristics of microplastics in water and sediment samples from the downstream Brantas River (Surabaya city). Observations of the abundance of microplastics in water and sediment at three stations during the dry season revealed a trend of increasing abundance downstream. Microplastics were abundant in the water at sta 1 with an average of 0.8 particles/L, sta 2 with 1.25 particles/L, and sta 3 with 1.02 particles/L. The abundance of microplastics in the sediment at sta 1 averaged 0.2 particles/gr, sta 2 0.51 particles/gr, and sta3 0.25 particles/gr. Meanwhile, in the rainy season, the abundance of microplastics in water and sediment shows a higher abundance compared to the dry season. Abundance of microplastics in the water at sta 1 with an average of 0.9 particles/L, sta 2 1.24 particles/L, and sta3 1.17 particles/L. The abundance of microplastics in the sediment at sta 1 averaged 0.55 particles/gr, sta 2 0.56 particles/gr, and sta3 0.60 particles/gr.

Microplastics contamination in two species of gobies and their estuarine habitat of Indian Sundarbans

Sundarbans, a Ramsar site of India is contaminated with heterogeneous microplastic wastes. Boddart's goggle eye mudskipper and Rubicundus eelgoby, were common gobies of Sundarbans estuary which accumulated microplastics during their normal biological activities. We estimated the abundance of microplastics in water, sediment; skin, gills, bucco-opercular cavity and gastrointestinal tract of these two goby fishes. Microplastic load estimated in gobies were 0.84 and 2.62 particles per fish species with a dominance of transparent, fibrous microplastics with 100–300 μm in length. ATR-FTIR and Raman spectroscopy revealed polyethylene as prevalent polymer. Surface degradations and adsorption of contaminants on microplastic surface were investigated by SEM-EDX analysis. Presence of hazardous polymers influenced high polymer hazard index and potential ecological risk index which indicated acute environmental threat to Sundarbans estuary and its resident organisms. Current study will provide a new information base on the abundance of microplastics and its ecological hazard in this biosphere reserve.

Identification of microplastics in water in the Sukolilo Coastal Area, Bangkalan Regency, East Java

Plastic pollution in coastal and marine areas will continue to increase as human activity increases to dispose of plastics directly into the aquatic environment. Microplastics are plastics that have long been polluted in waters that have been degraded by nature into small particles &lt;5mm. Microplastics are widespread and can be found in water, biota and aquatic sediments. This study aims to determine the abundance of microplastics in water in the coastal waters of Sukolilo village, Bangkalan Regency. This research method uses purposive sampling method, at 3 collection stations, each water sampling is filtered as much as 50 liters. Microplastic identification was carried out with H2SO4 and H2O2 solutions with a concentration of 30% after which visual analysis was carried out using a microscope which was used to determine the color and type of microplastics found. The results of observations found three forms of microplastics, namely fiber, fragments, film. In water samples, the highest pollution was found with an average of 4.32 particles / L at station 14.32 particles / L, station 2 as many as 3.36 particles / L and station 3 as many as 3.28 particles / L. The percentage of microplastic forms in the highest water is fiber with a percentage value of 91%.

Microplastic pollution and ecological risk assessment of Yueqing Bay affected by intensive human activities

Microplastics (MPs) are a widespread environmental problem posing ecological risks in the ocean. We investigated the abundance, spatial distribution, characteristics and ecological risks of MPs in surface seawater, sediments and organisms in Yueqing Bay, China. MPs were detected in both environmental media and organisms. The overall abundance (0.24 items/m3 seawater, 6.13 items/kg dry sediment, 0.77 items/individual in organisms) was low to medium compared with other coastal areas. The MPs were mainly derived from the high-intensity mariculture and shipping in the bay, as well as industrial and human activities along the surrounding coast. The abundance of MPs in water of the left (western) bay (0.39 items/m3) was considerably higher than that of the right (north-eastern) bay (0.07 items/m3) due to the different levels of population and economic development on the left and right coasts. The ecological risk assessment showed generally low to medium risk from MPs pollution in Yueqing Bay, with higher ecological risk index (H) and potential ecological hazards (RI) of MPs polymers in water samples. These data emphasize the need for timely and effective action to reduce the contribution of intensive human activities to MPs pollution and provide information for further ecotoxicological studies, pollution control, and policy development of MPs.

Microplastics contamination in the green mussels (Perna viridis) cultured for human consumption in Thailand

Recent trends in the aquaculture industry have introduced massive quantities of microplastics (MPs). This study investigated the MPs contamination in green mussel (Perna viridis) farms located on the east (Sriracha Bay) and west (Phetchaburi) sides of the Gulf of Thailand. The abundance and characteristics of MPs were determined by Nile Red tagging while polymer composition was determined by micro-Fourier Transform Infrared Spectroscopy. MPs were detected in water, sediments, and mussels with 100% detection frequency. The average abundance of MPs in water, sediments, and green mussels at Sriracha Bay was 41.5 ± 6.0 particles/L, 474.6 ± 102.6 items/kg, and 3.2 ± 1.6 items/individual, respectively while it was lower at Phetchaburi. Fragments were dominant morphotype while high-density polyethylene was the dominant polymer. No significant difference was found between the young and older mussels while a significant difference was observed in mussels between the two farms. Policies should be implemented to reduce the MPs contamination in aquaculture environments.

Analysis of Microplastic Abundance in Lake Siombak, Medan Marelan, Medan

Microplastics are one of the pollutants that threaten aquatic ecosystems and have become the focus of research in recent years by environmentalists worldwide. In addition to harmful base materials, microplastics have hydrophobic characteristics, so chemicals such as Persistent Organic Pollutants can stick to microplastics and cause chemical pollution in aquatics. Siombak Lake is located in the coastal area of Medan City, and it is predicted to be a microplastic distribution channel to the aquatics. This study aimed to analyze the abundance of microplastics in water, sediment, and fish in Siombak Lake. Sampling was conducted from November 2021 – January 2022 at Siombak Lake. Water samples to be analyzed were added with 90 g NaCl, then filtered and separated visually using a microscope. Microplastic in the sediment is separated by drying, volume reduction, density separation, filtration, and visual sorting. Fish samples were dissected, and then the digestive tract content of fish was diluted with 10 ml of saturated NaCl. The abundance of microplastics obtained in waters ranged from 93-519 particles/m3, and the Number of microplastics in sediment ranged from 521-1481 particles/kg dry sediment, while the abundance of microplastics in fish samples ranged from 0-6 particles/individual.Keywords: Microplastic, Abundance, Coastal, Pollutant, Siombak Lake

Microplastics Occurrence in Fish from Tocagua Lake, Low Basin Magdalena River, Colombia

Following global trends, research to determine the presence and abundance of microplastics (MPs) in environmental matrices in Colombia has focused on the coastal and marine environments. However, little scientific information is available on the impact of this pollutant on wetlands and fish. In this study, we provided scientific data on the occurrence and abundance of MPs in water and fish from Tocagua Lake, an important wetland in the Colombian Caribbean, and the unique habitat of wild cotton-top tamarins (Saguinus oedipus). Water (72) and fish (228 individuals of six species) samples were collected during four sampling events and two climatic seasons (wet and dry). A total of 1174 microplastic particles were collected in water with an average abundance of microplastics at the six stations sampled during four sampling events of 0.96 ± 0.40 MPs/L, and 648 MPs were identified in the gastrointestinal tract of 191 individuals, corresponding to a frequency of occurrence of 83.7%. Black- and blue-colored fiber MPs were particles that predominated in both matrices (water and fish), and seven types of polymers were identified through attenuated total reflectance Fourier transform infrared spectroscopy analysis. The abundance, type, and color of MPs in water and fish were not significantly different between seasons.

Distribution Characteristics and Risk Assessment of Microplastics in Water of Different Functional Parks in Guilin

The water environment capacity of urban parks is small, and their self-purification ability is poor. They are also more likely to be affected by microplastics (MPs), which cause an imbalance of the water micro-ecosystem. Based on the functional characteristics of parks (comprehensive park, community park, and ecological park), this study investigated the distribution characteristics of MPs in the water of Guilin parks through spot sampling, microscopic observation, and Fourier transform infrared spectroscopy. In addition, the pollution risk index and the pollution load index were used to evaluate the pollution risk of MPs.The results showed that the abundances of MPs in the park surface water and sediments ranged from 104.67-674.44 n·m-3 and 95.57-877.78 n·kg-1, respectively. There were four main shape types of MPs:fragments, fibers, films, and particles. MPs were dominated by fragments and fibers with small sizes (<1 mm). The polymers of MPs were polyethylene and polyethylene terephthalate. There were significant differences in the abundance of MPs in the water of different functional parks, and the abundance of MPs in comprehensive parks was the highest. The abundance of MPs in park water was closely related to the function of the park and the number of people entering the park. The pollution risk of MPs in the surface water of Guilin parks was low, whereas the pollution risk of MPs in sediments was relatively high. The results of this study indicated that tourism was an important source of MPs pollution in the water of Guilin City parks. The pollution risk of MPs in the water of Guilin City parks was mild. However, the pollution risk of MPs accumulated in small freshwater waters of urban parks requires continued attention.

Common laboratory reagents: Are they a double-edged sword in microplastics research?

Understanding and communicating instances of microplastic contamination is critical for enabling plastic-free transitions. While microplastics research uses a variety of commercial chemicals and laboratory liquids, the impact of microplastics on these materials remains unknown. To fill this knowledge gap, the current study investigated microplastics abundance and their characteristics in laboratory waters (distilled, deionized, and Milli-Q), salts (NaCl and CaCl2), chemical solutions (H2O2, KOH and NaOH), and ethanol from various research laboratories and commercial brands. The mean abundance of microplastics in water, salt, chemical solutions, and ethanol samples was 30.21 ± 30.40 (L−1), 24.00 ± 19.00 (10 g−1), 187.00 ± 45.00 (L−1), and 27.63 ± 9.53 (L−1), respectively. Data comparisons revealed significant discrepancies between the samples in terms of microplastic abundance. Fibers (81 %) were the most common microplastics, followed by fragments (16 %) and films (3 %); 95 % of them were <500 μm, with the smallest and largest particle sizes recorded being 26 μm and 2.30 mm, respectively. Microplastic polymers discovered included polyethylene, polypropylene, polyester, nylon, acrylic, paint chips, cellophane, and viscose. These findings lay the groundwork for identifying common laboratory reagents as a potential contributor to microplastic contamination in samples, and we offer solutions that should be integrated into data processing to produce accurate results. Taken together, this study shows that commonly used reagents not only play a key role in the microplastic separation process but also contain microplastic contamination themselves, requiring the attention of researchers to promote quality control during microplastic analysis and commercial suppliers in formulating novel prevention strategies.

Occurrence, distribution and risk assessment of microplastics and polycyclic aromatic hydrocarbons in East lake, Hubei, China

The pollution of microplastics (MPs) and polycyclic aromatic hydrocarbons (PAHs) in the environment is a global problem, which has attracted extensive attention of many researchers. In present study, MPs and PAHs are investigated to study the impact of human activities and their possible relationship in China's second largest urban lake, East Lake. The abundance of MPs are 3329.19 ± 2059.26 particles/m3 and 2207.56 ± 1194.04 particles/kg in water and sediment, respectively. MPs are predominantly characterized by fibers, polypropylene (PP) and polyethylene (PE), colorlessness in water and sediment. The abundance of MPs in water with frequent human activities is higher, which is reversed in sediments, indicating that disturbance is not conducive to the enrichment of MPs in sediments. The concentration of 16 PAHs are 36.95 ± 13.76 ng/L and 897.08 ± 232.34 ng/g in water and sediment, respectively. PAHs in water are mainly 2-3-ring, while there are 4-ring PAHs in sediments. The good corresponding relationship between MPs and PAHs indicates that human activities have an important impact on the distribution of pollutants compared to the interaction of pollutants. In addition, the significant positive correlation between lakeshore length and water MPs abundance indicates that surface runoff may be an important source of water MPs. The pollution load index shows that MPs in sediment has reached moderate to severe pollution level, while the water is slightly polluted level. The potential ecological risk assessment results show that more than half of the sediment sites are at dangerous to very dangerous ecological risk level.

The abundance of microplastic pollution along the Jajroud river of Tehran: Estimating the water quality index and the ecological risk

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

Evidence of microplastics in the Chi River Basin, Thailand: Anthropogenic influence and potential threats to edible arthropods

Microplastics (MPs) are an emerging pollutant in freshwater that have become a cause for concern among researchers around the world. In this study, MPs contamination in water, sediment and edible arthropods of the upper Chi River and Pong River was studied to analyze the influence of anthropogenic activities on contamination in the river environments and arthropods. Five species of arthropods were observed to assess the impact of MPs contamination: Caridina sp, Macrobrachium sp., Aethriamanta sp., Aciagrion sp. and Sphaerodema molestum. MPs were found in water and sediment samples with an average of 141 items/m3 and 9.5 items/kg, respectively. Fibers were major MPs shape in water (63%) and sediment (81.9%). MPs with dark blue color were numerically dominant in water (28%) and sediment (39.6%). MPs in edible arthropods were in the range of 0.25 – 8.0 items/individual. A wider variety of polymer types was found in the rivers than in the edible arthropods. Overall, dark blue colored PP fibers were found to be the most abundant in water, sediment and edible arthropods with MPs mostly ranging 1000–2000 µm in size. MPs concentration in water correlated with community size (p-value <0.05), and the abundance in sediment correlated with the number of roofs (p-value <0.05) and the distance of the rivers from communities (p-value <0.05). Anthropogenic activities significantly contributed to abundance of MP in water and sediment. Industrial, community and fish farming contributed to MP in water and agriculture and community directly correlated with MP in sediment with p-value <0.05 at 95% confidence. The results indicate the significant influence of anthropogenic activities on the amount of MPs in water and sediment, directly relating to contamination in edible arthropods. Domestic wastewater and plastic waste are likely to be the leading causes of existing MPs in the rivers and arthropods.

Microplastic pollution in the surface water and sediments from Kallar Kahar wetland, Pakistan: occurrence, distribution, and characterization by ATR-FTIR.

This study reports the distribution of microplastics in surface water and sediments collected from Kallar Kahar wetland, Punjab, Pakistan, which is a game reserve and hosts migratory birds during winter season. Microplastics were extracted using density separation and wet oxidation method. The microplastics identification was done under a stereo-microscope, and their polymer compositions were characterized using an attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The average abundance of microplastics in water and sediment samples was 88 ± 14.5 items/Land 5720 ± 2580 items/kg, respectively. The dominant shape groups of microplastics in water were fiber (58.7%), irregular fragments (32.4%), and beads (8.7%) with dominant colors as transparent > black > yellow ≈ white > red > green > pink > blue. Similar distribution in sediments was found, i.e., fiber (61.2%), irregular fragments (28.4%), and beads (10.3%) with dominant colors as transparent > pink > white > red ≈ black > blue > brown > green ≈ yellow. The ATR-FTIR spectra of visible microplastics were identified to be polypropylene (PP), high density polyethylene (HDPE), ethylene vinyl acetate (EVA), low density polyethylene (LDPE), nitrile, polymethyl methacrylate (PMMA), latex, and polyethylene terephthalate (PETE). In the study area, recreational activities, improper waste disposal, and runoff from catchment areas are the main reasons for the contamination of microplastics in the Lake. The pollution load can be minimized by taking measures such as creating awareness, promotion of ecotourism, and reducing plastic use.

Monitoring of microplastics in the clam Donax cuneatus and its habitat in Tuticorin coast of Gulf of Mannar (GoM), India

Microplastics (MPs) in the marine environment are ubiquitous. The ingestion of these pollutants by marine organisms has drawn global attention. This work studies the distribution pattern and characteristics of MPs found in the body of the clam Donax cuneatus and its environment in order to understand the possible relationship between the MP concentration in the environment (water and sediment) and that in the clam’s body. Samples of D. cuneatus were collected from the coast between Vembar and Periyathazhai in Tuticorin district along GoM. MP concentrations range from 0.6 to 1.3 items/g (wet weight) in clams, 10–30 items/l in water, and 24–235 items/kg in sediment. Small-sized clams contain the highest concentration of MPs. Hence it is hypothesised that allometric relationship exists between body size and MP concentration, depending on the surface-area to volume ratio. MP abundance in clam body has a clear, positive, significant correlation with MP abundance in sediment but not with abundance of MP in water. Microplastics of fiber type with size 100–250 μm have a predominant presence in clams. The study identified ten types of polymers, of which polyethylene is the most common polymer in all sample types. FTIR-ATR spectra and surface morphology indicate that most of the microplastics have been strongly weathered. Energy dispersive X-ray spectroscopy analysis detected heavy metals associated with MPs like Cd, Pb, Cu, Zn, Ni and Fe. Filter-feeding clams like Donax sp. can provide valuable information on the spatial patterns of MP distribution, and so can act as bio-indicators in monitoring MP pollution in coastal areas.

Microplastic contamination on the lower Chao Phraya: Abundance, characteristic and interaction with heavy metals

While a large number of studies on microplastics (MPs) in the western hemisphere have been performed, few studies are available in the eastern hemisphere, especially in Southeast Asia. In this study, the abundance of MPs in water and sediment samples from the Chao Phraya River at the Tha Pra Chan area, Thailand, was investigated. Water samples were collected by a manta trawl, and sediment samples were collected by a Van Veen grab sampler. The average number and concentration of MPs in water samples were 80 ± 65 items/m³ and 53.3 ± 58.4 mg/m³, respectively. The average number and concentration of MPs in sediment samples were 91 ± 13 items/kg and 4.9 ± 3.4 mg/kg, respectively. The main morphologies of MPs were fragments and fibers, mostly white. Polypropylene (PP) was the dominant polymer type found in both water and sediment. Moreover, the content of heavy metals (Cr, Cu, Ni, and Pb) on MPs was extracted by aqua regia solution and analyzed by ICP-OES. Results show high concentrations of Pb and Cu adsorbed on MPs in the study area. In brief, this study suggests that there are high levels of MPs in the water and sediments of the Chao Phraya River at the Tha Pra Chan area.

Pollution Characteristics of Microplastics in Migratory Bird Habitats Located Within Poyang Lake Wetlands

Microplastic pollution (plastics with particle sizes<5 mm) has become a serious problem. In this study, we sampled the surface water, sediment, and bird excrement from the shore, center of the lake, and active areas for birds in Baisha Lake, which is key habitat for migratory birds in the Poyang Lake wetlands. The microplastics were separated by flotation separation, and then, we analyzed the pollution characteristics of this area. The main results were as follows. ① There were significant differences in the abundance of microplastics in water and sediment at different sampling points in the study area. The average abundance of microplastics in water and sediment were 263.28 per·m-3 and 215.9 per·kg-1, respectively. The average abundance of microplastics in migratory bird feces was 4.93 per·g-1. ② There were four kinds of microplastics in the surface water in terms of the different morphologies of particles, namely, pellets, films, fragments, and fibers, among which pellets were the major type. The main colors of microplastics were red, yellow, green, blue, purple, black, and transparent. The rank in terms of the size of microplastics was follows: < 1 mm > 1-2 mm > 2-3 mm > 3-5 mm, and the abundance decreased with the increase of particle size. ③ There were also four kinds of microplastics with different morphologies in the sediment, namely, pellets, films, fragments, and fibers. The main colors of these microplastics were red, yellow, blue, purple, black, and transparent. Microplastic sizes on the shore of the lake and bird habitat were mainly < 1 mm, and 1-2 mm particles were mainly detected in the center of the lake. ④ There were four types of microplastics in the excrement of migratory birds, namely, pellets, films, fragments, and fibers. The colors of these microplastics were red, yellow, green, purple, and transparent, and the particle size was mainly < 1 mm. ⑤ There was no consistency in the types of microplastics in the water body, sediment, and bird droppings. However, the size distribution for water and bird excrement was consistent. The results indicate that Poyang Lake bird habitat is polluted by microplastics, and the birds are inevitably exposed to microplastics. This study warns that microplastics will be an emerging threat to migratory birds.

Spatial and temporal distribution of microplastics in water and sediments of a freshwater system (Antuã River, Portugal)

Microplastics (particles with a size<5mm), one of the most emerging aquatic pollutants, are of particular concern since they can reach high densities and interact with biotic and abiotic environment. The occurrence of microplastics in freshwater systems is less understood than in marine environment. Hence, the present study aims to provide new insights into microplastics abundances and distribution in Antuã River (Portugal) by applying the isolation method of wet peroxide oxidation with addition of zinc chloride to water and sediment samples collected in March and October 2016, in three sampling sites. The abundance of microplastics in water ranged from 5 to 8.3mgm−3 or 58–193itemsm−3 in March and from 5.8–51.7mgm−3 or 71–1265itemsm−3 in October. In sediments, the abundance ranged from 13.5–52.7mgkg−1 or 100–629itemskg−1 in March and from 2.6–71.4mgkg−1 or 18–514itemskg−1 in October. The water and sediment samples with the greatest abundances were from São João da Madeira and Aguincheira, respectively. Spatio-temporal distribution showed different pattern according to methodological approaches, seasonal and hydrodynamic conditions and the proximity to urban/industry areas. Analysis of plastics by Fourier transform infrared spectroscopy underline polyethylene and polypropylene as the most common polymer types identified in this work. The low medium high oxidation ratio was 56:22:22 (%) in March and 61:31:8 (%) in October. Foams and fibers were the most abundant type in São João da Madeira, while fibers and fragments were the most abundant in Aguincheira and Estarreja in water and sediment samples, respectively. This study emphasizes the importance of rivers as carriage systems of microplastics. Further studies should be performed to identify point sources in order to mitigate the microplastics contamination in aquatic systems.