Identification of Microplastics Content in Sediment, Water and Digestive Channel of Milkfish (Chanos chanos) in Sidoarjo Pond

Distribution characteristics of microplastics in the seawater and sediment: A case study in Jiaozhou Bay, China

The large input of mulch film and organic fertilizer have led to increasingly serious microplastic pollution in farmland soil of China. In this study, the microplastic pollution of peanut farmland in Dezhou City, Shandong Province was investigated. The effects of different mulching years (0, 3, 5, and 8 years) and organic fertilizer application on the abundance, particle size, color, and shape of microplastics in farmland soil were analyzed. The results showed that the average abundances of microplastics in peanut soil were 65.33, 316.00, 1 098.67, and 1 346.34 n·kg-1, respectively, after 0, 3, 5, and 8 years of film mulching. The abundance of microplastics decreased with the increase in soil depth. The abundance of microplastics in 0-10, 10-20, and 20-30 cm topsoil was 1 076.00, 603.5, and 440.25 n·kg-1, respectively, and the abundance of microplastics increased significantly with increasing years of film mulching and organic fertilizer application (P<0.05). The particle size of microplastics in the sample plot <1 mm accounted for 77.30% of the total content, and with the increase in film mulching age, the proportion of microplastics with small particle size (<1 mm) increased significantly (P < 0.05). With the increase in soil depth, the proportion of microplastics with small particle size also gradually increased, whereas the application of organic fertilizer had no significant effect on the particle size of microplastics. The color of microplastics in the plot was mainly transparent (49.77%), followed by black (16.35%) and white (16.27%). The planting age and organic fertilizer application had no significant effect on the color of microplastics in the soil (P > 0.05), but the mulching age significantly increased the proportion of transparent microplastics. The abundance proportion of the five types of microplastics were 49.77%, 25.41%, 19.15%, 3.26%, and 2.41%, respectively. These field soil microplastics were mainly composed of polyethylene (PE), polypropylene (PP), and polystyrene (PS) polymers, accounting for 21.37%, 18.57%, and 19.77% of the total, respectively. Therefore, microplastics were widely present in the soil of the peanut field cultivated layer in Dezhou, Shandong, and the applications of mulch film and organic fertilizer were the main source. This study provides an important basis for the prevention and control of soil microplastic pollution in peanut fields.

To explore the pollution characteristics and ecological environmental risk of microplastics in water and sediment of the Yilo River Basin， water and sediment samples were collected from 15 monitoring sections， the types， abundance， and particle size of microplastics in the water and sediment were identified using an Agilent 8700 laser infrared imaging system （LDIR）， and the ecological and environmental risk of microplastics in water and sediment of the Yiluo River Basin were assessed by the pollution load index （PLI） and polymer risk index （H）. The results showed that the types of microplastics are consistent in the water and sediment of the Yiluo River Basin， but the proportion of microplastics differs. For example， fluororubber （FPM）， chlorinated polyethylene （CPE）， polyurethane （PU）， and acrylate copolymer （ACR） microplastics accounted for 35.22% and 23.58%， 12.12% and 5.19%， 7.11% and 13.52%， and 5.33% and 22.07% of the microplastics in the water and sediment， respectively. The particle size of microplastics in the water and sediment is mainly concentrated in the range of 0-100 μm， accounting for 89.01% and 83.88% of the distribution， respectively. The average abundance of microplastics in the water and sediment was （412.48±39.91） n·L-1 and （11 646.58±3 129.37） n·kg-1， respectively， and there was a significant difference in the abundance of microplastics among different sections. The maximum abundance of microplastics of 728.86 n·L-1 and 52 864.44 n·kg-1 occurred in water and sediment of sections S12 and S3， respectively. The maximum average abundance of FPM microplastics was （145.25±40.52） n·L-1 in water， and the maximum average abundance of ACR microplastics was （2 877.92±2 255.12） n·kg-1 in sediment. The pollution load index method and polymer risk index method showed consistency in the ecological environment risk assessment results of microplastics， and microplastics in the water and sediment of the Yiluo River Basin generally present high risk or above.

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.

Microplastics as a prevalent pollutant in water bodies have recently attracted widespread attention. To investigate the spatial and temporal distribution characteristics of microplastics in freshwater rivers and their migration patterns, the surface water, sediments, and subsidence zone of the Xiangxi River, a tributary of the Yangtze River, were sampled and analyzed in November 2020 and April 2021, respectively. The results showed that the average abundance of microplastics in the surface water of Xiangxi River was (6.64±1.32) n·L-1 in flat water and (5.00±1.07) n·L-1 in dry water, the average abundance of microplastics in sediments was (0.56±0.13) n·g-1 in flat water and (0.41±0.09) n·g-1 in dry water, and the average abundance of microplastics in the subsidence zone was (0.53±0.15) n·g-1 in flat water and (0.68±0.18) n·g-1in dry water. There were significant differences in the abundance distribution of microplastics in the surface water, sediments, and subsidence zone (P<0.05). In the surface water and sediments, the particle size of microplastics was mainly distributed in the range of 0.1-0.5 mm, and in the subsidence zone, it mainly ranged from 1-5 mm. The color of microplastics was mainly transparent in the surface water and subsidence zone and blue in sediments. The morphology of microplastics in the Xiangxi River basin was mainly fiber, and the materials were mainly polyethylene (PE) and polypropylene (PP). There were many factors affecting the distribution of microplastics. The analysis results showed that the abundance of microplastics in the surface water was negatively correlated with the flow rate of the water body. The abundance of microplastics in the sediment was related to the substrate type of the riverbed and negatively correlated with the substrate particle size. Combined with the microplastic abundance data of each sampling site, it was found that there was a significant migration process of microplastics in the spatial distribution of the Xiangxi River in the watershed. Along the river longitudinal direction, the longitudinal migration of microplastics in the surface water was along the river direction, and in the vertical direction, it showed the mutual migration between the water body and the subsidence zone and the water body and sediments.

Considering that microplastics are widespread in the marine environment, in this study we evaluated the presence, identify distribution, abundance, shape type, and color of microplastics in surface sediment along the Montenegrin coast, on the Adriatic Sea. These preliminary results provide the first published record of microplastics found in the surface sediment of this area and highlight the importance of microplastics as a component of marine debris. We documented the presence of microplastics at all sampling locations. The identification of polymer types was performed using Fourier-transform infrared (FTIR) spectroscopy, whereby the presence of three polymer types became evident: polypropylene (54.5%), polyethylene (9.7%), and acrylate copolymer (2.0%). Another 22.2% of particles were unidentified polymers, and the remaining 11.5% were non-synthetic materials. The most common shape type of microplastics was filaments (55.5%), followed by granules (26.3%), fragments (14.9%), and films (3.3%). The dominant colors of microplastics followed the order: blue &gt; yellow &gt; red &gt; clear &gt; black &gt; green &gt; blue-white &gt; white. The average abundance of microplastics in all sampling locations was 609 pieces of microplastic/kg of dry sediment. Compared with other studies, the surface sediment of the Montenegrin coast is moderately to highly polluted with microplastics, depending on the examined location.

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.

The farmland ecosystem faces the emerging risk of microplastic pollution. To investigate the distribution characteristics of microplastics in agricultural soils in Guyuan City, the abundance, type, color, size, and shape of microplastics in Guyuan City agricultural soils were analyzed using field survey, microscopic observation, and Fourier transform infrared spectroscopy. In addition, the risk of microplastic pollution was assessed using the pollution load index method (PLI). The results showed that the microplastic abundance of agricultural soils (0-20 cm) in Guyuan City ranged from 186.32 to 1286.24 n·kg-1, and the microplastic abundance of soils in facility agriculture increased significantly by 35.56% and 228.91% compared with those in non-facility agriculture with and without film, respectively, and the microplastic abundance in the arable layer was 0.31 times higher than that in the plough pan layer. PE (26.42% to 62.83%) and PP (27.64% to 42.62%) were the main microplastic polymer types, and the number of soil polymer species was significantly greater in facility agriculture than that in non-facility agriculture. Microplastics <100 μm accounted for 32.21%-42.52%, whereas >1000 μm accounted for only 0.28%-12.31%. The particle size of microplastics in the arable layer was 47.39% higher than that in the plough pan layer, and the particle size of microplastics was the largest in facility agriculture and the smallest in non-facility film-free planting. Microplastics were mostly in the form of films, fibers, fragments, and microbeads, with the greatest abundance in the form of fibers and the second largest in the form of films. A total of seven colors of microplastics were monitored, mainly white and black. The overall risk of contamination in the study area was low, and the highest risk of microplastic contamination was found in the soil of facility agriculture. The results of the study will provide data reference for the assessment of microplastic contamination in agricultural soils and microplastic soil environmental behavior in China.

Assessment of the water quality pollution index and ecological risk of microplastic pollution along the Tambakoso River in Surabaya, Indonesia

Microplastic pollution poses threats to aquatic ecosystems and human health. In this study, in order to investigate the characteristics of microplastic occurrence in different environmental media, the abundance, particle size, shape, color, and composition types of microplastics in the water column, sediment, riparian zone soil, and the benthic snail Bellamya aeruginosa of the Manao River were analyzed using field sampling, microscopic observation, and Fourier infrared spectroscopy. The results showed that the average abundance of microplastics in the surface water of the Manao River was (5.9±0.26) n·L-1; the abundance of microplastics in the upper sediment (by dry weight) was (1.35±0.1) n·g-1, and that in the lower sediment (by dry weight) was (0.93±0.12) n·g-1. The abundance of microplastics in the near riparian zone soil (by dry weight) was (0.68±0.16) n·g-1, and that in the far riparian zone soil (by dry weight) was (0.69±0.14) n·g-1, and the abundance of microplastics in the B. aeruginosa was (2.06±0.25) n·g-1. The analysis results showed that the abundance of microplastics in the upper and lower sediments were positively correlated; the abundance of microplastics in B. aeruginosa was positively correlated with the abundance of microplastics in the upper and lower sediments, respectively; and the abundance of microplastics in the near and far riparian zone soils were also correlated. Most of the microplastics within each environmental medium and B. aeruginosa were <0.1 mm in size, mainly in the form of fibers and fragments, mainly blue and black in color, and mainly composed of polypropylene (PP) and polyethylene (PE). It was found that microplastics in riparian zone soils mainly originated from the fragmentation and decomposition of agricultural plastic films. The results of this study shed light on the accumulation of microplastics in macrobenthic organisms through the investigation of microplastics in multi-environmental media and in the B. aeruginosa, which helps us to understand the potential ecological risk of microplastics in a comprehensive manner.

Marine waste, especially plastic waste, is a complex problem faced by areas close to the beach/coastal area. This problem also occurs in Kendari Bay which has a unique character because of its position stretching in the middle of Kendari City, its shape is like a horse’s footprint and as a mainstay tourist attraction in Southeast Sulawesi. This study aims to analyze the distribution of microplastic abundance in sediments and marine biota, analyze water quality in the microplastic abundance distribution area, and determine efforts to mitigate pollution of plastic waste in Kendari Bay. A sampling of sediments and biota from 2 stations (settlement and port) using paralon pipes at depths of 0-5 cm and 5-10 cm. Seawater quality parameters are parameters related to solid waste pollution based on UNESCO-WHO-UNEP and the method for water quality analysis refers to APHA-AWWA-WEF. The results showed that the types of microplastics found were film, fragment, and fiber. The average abundance of microplastics in Station I (Mata Village, Kendari City) and Station II (Kendari Archipelago Harbor) at a depth of 0-5 cm range from 426.82-424.92 particles/kg. This value is higher than the microplastic abundance at 5-10 cm depth, which is between 276.50 to 363.74 particles/kg. The average abundance of film-type microplastics and fragments at 0-5 cm depth was higher at Station I (203.75 particles/kg and 359.90 particles/kg). The microplastic category of fragments/debris at a depth of 5-10 cm, was found at Station II (409.06 particles/kg). Biota found in Station I sediments were blood shells (AnadaraSp) With microplastic fragment type (1 particle) and fiber type (2 particles) with an average abundance of 0.12 particles/Ind. Fiber-type microplastics are found in tofu skin (Maretrixmaretrix) of 5 particles with an average abundance of 0.5 particles/Ind. and Violin Crab (Uca), 1 particle with an average abundance of 0.04 particles/Ind. Water quality in the area of microplastic abundance found NH3, BOD, Phosphate (PO43-), Nitrate (NO3−), Phenol (C6H5OH), detergent and fat oil content have exceeded the quality standard. Mitigation efforts that can be done are 6R, separating the types of waste from the beginning, encouraging the role of government through education and regulation, research and technology support as well as bay cleaning measures so as to beautify the bay and improve the comfort of the local community and visitors so that the function of Kendari Bay as a tourist area the mainstay coast of Southeast Sulawesi remains sustainable.

Mangroves, as the key blue carbon ecosystem, are considered ‘potential sinks’ for microplastics (MPs) in the land-ocean interface zones. However, there is limited understanding of enrichment patterns of MPs in mangrove blue carbon ecosystem, particularly in relation to human activities. This study explored the abundance, composition, and diversity of MPs in mangrove and non-mangrove sediments in Zhanjiang Bay (ZJB) to investigate the effects of human activities on MPs enrichment patterns in the blue carbon system. The results showed that MPs were widely prevalent in all sediment samples, and the abundance of MPs was significantly higher in all mangrove sediments than in non-mangrove sediments (P &amp;lt; 0.05). Furthermore, the average abundance of MPs was found to be 263.67 ± 85.25 items/kg in non-mangrove sediment samples, whereas in mangrove sediment samples, it was 618.17 ± 71.75 items/kg. The average abundance of MPs in mangroves was about 1.6 times higher than that in non-mangroves, indicating that mangroves have an interception effect on MPs, and human activities are the key factor leading to the difference in MPs enrichment patterns between mangroves and non-mangroves. Furthermore, the predominant MPs shapes in both mangroves and non-mangroves are fragments, with multicolor and green being the most common colors and most MPs sizes ranging between 100 and 330 µm. Besides, there was no significant relationship found between MPs abundance and particulate organic carbon (P &amp;gt; 0.05), indicating that MPs pollution didn’t significantly alter the natural POC pool in ZJB. Overall, this study provided important baseline information on MPs pollution in the mangrove blue carbon ecosystems in ZJB, which was implications for future mitigation of MPs pollution and the management of mangrove ecosystem.

The occurrence of microplastics in aquatic environments has attracted increasing interest from both the public and scientists, especially their migration behaviors. Although several environmental behaviors of microplastics have been studied, the issue of microplastic suspension and deposition in lake sediment-water systems remains to be elucidated. In this study, we built an indoor sediment-water system with input and output rivers that simulated the actual situations in lakes, and aimed to explore the suspension and deposition behavior of microplastics using eight group experiments. The abundance of microplastics in overlying water and sediments in different periods was analyzed, and the characteristics of hydrodynamic disturbance on microplastic suspension and deposition were identified. Importantly, the exchange of microplastics in sediments and water under dynamic flow conditions was assessed. The results showed that the middle-scale experiment designed in this study effectively simulated the dynamic transport process of microplastics in lakes, and the hydrodynamic force had a significant impact on the suspension and deposition behaviors of microplastics. The average abundance of polystyrene, polyethylene terephthalate and polyamide microplastics was 1.07, 0.60 and 0.83 particles/L in overlying water during the suspension experiments, respectively. This showed a pattern of first rising and then falling with the extension of suspension time. Even in the environment with the maximum input water volume (8000 ml/min) in this study, only microplastics at a depth of 0 to 2 cm from the sediment were suspended. The average abundance of microplastics was 313.02 particles/kg during the deposition experiments, which gradually increased with the extension of deposition time in sediments. Finally, microplastic sizes in water of the suspension experiments and in sediments of the deposition experiments were concentrated in the range of 500 to 1500 μm and 300 to 1000 μm, respectively.

It has been confirmed that microplastics widely exist in the natural environment, causing potential harm to organisms and humans. An investigation into the occurrence of microplastics is helpful to understand the level of pollution of microplastics in urban rivers and sediments. In this study, eight sampling points of water samples and three of sediments samples were placed along the North Canal and Huaihe River in Beijing, to compare the composition and distribution characteristics of the abundance, particle size, color, shape, and species of microplastics. The results showed that the abundance of microplastics in the water and sediments of the North Canal were(1941±201)-(8155±1781) n·m-3(n refers to the number of microplastics) and (120±11)-(268±31) n·kg-1, respectively. The average abundance of microplastics in the water of the North Canal was 4160 n·m-3. Compared with the North Canal, the pollution degree of microplastics in the Huaihe River was lower with an average abundance of 2357 n·m-3. Furthermore, the abundance of microplastics in the water and sediments in the upper reaches of the North Canal was higher than that in the lower reaches. No significant difference of microplastics distribution was observed in the water of the Huaihe River on the whole; however, there was a marked difference in abundance between the two distant locations. The main particle size range of microplastics at all site points was<300 μm, and mostly white/transparent(50.75%-83.91%); the main shape were fragments(50.00%-95.08%) and fibers(3.86%-30.00%). Polyurethane(PU) and ethylene vinyl acetate(EVA) were two main plastic species found at all sites. Microplastics in the water and sediments of the North Canal might have originated from urban construction and development, while the surrounding villages might have only affected the abundance of microplastics in the Huaihe River.

Plastic waste in marine waters will undergo a degradation process that breaks down large plastic pieces into smaller particles called microplastics. The abundance of microplastics, caused by their small size (&lt;5mm) can be easily indirectly consumed by aquatic animals. Anadara granosa is one of the bivalves that is quite vulnerable to microplastic contamination because it has the nature of a filter feeder which means it can sift particles and organic matter around it. The purpose of this study was to determine the characteristics, abundance, and types of microplastic polymers in blood clams (A. granosa). The results of microplastic observations made on 60 blood clams were 153 microplastic particles identified from 47 individuals (78%) of contaminated blood clams with an average microplastic abundance of 0.591 ± 0.083 item/gr. Fiber-type microplastics are the most dominant form found and blue is the most dominant color found in the sample. Based on the average abundance of microplastics in Anadara granosa in the coastal area of Palopo City, it is lower than several studies that have been conducted previously. Fourier Transform-Infra Red was conducted to determine the type of polymer in microplastics. Three types of polymers were found in the Anadara granosa samples polyethylene terephthalate (PET), polystyrene, and polyester. The three types of polymers have effects on human health such as respiratory problems, skin irritation, and genotoxicity. Action is needed to prevent microplastic pollution in Palopo City’s rivers before microplastic pollution becomes more severe in the future.