THE IDENTIFICATION OF MICROPLASTICS IN GILLS AND DIGESTIVE TRACT IN TILAPIA FISH (Oreochromis mossambicus) IN LAKE TOBA

Microplastics are small plastic particles under 5 mm in size that have contaminated a lot of ecosystems, both aquatic and on land. The existence of heaps of garbage and the existence of fishing activities around residential areas are some examples of anthropogenic activities that are on the edge and water bodies of the Selorejo Reservoir. This study aims to observe the contamination of various types of microplastics and their abundance in water and sediment samples taken from the Selorejo Reservoir. Sampling was carried out using the selected method (purposive sampling) at five different stations, including the Konto River inlet, Kwayangan River inlet, settlements (blendrang), tourism areas, and reservoir outlets. Each station has 3 transects (as replicates) and about 100 liters of water and 1000 grams of sediment are taken. Destruction of water and sediments uses 30% H2O2 and 30% H2SO4 acid to remove organic components that are still attached and to facilitate observation under a stereo microscope with 400X magnification. Based on the results of an analysis of the abundance of microplastics in the waters of each station, the highest abundance of microplastics was successively found in the Konto river inlet with a total abundance value of 39.27x101 particles/liter, then in the residential part (blendrang) a number of 35.34x101 particles/liter, tourist areas 33.67x101 particles/liter, outlet 30.36x101 particles/liter and Kwayangan river inlet 29.67x101 particles/liter. Meanwhile, the highest total abundance of microplastics found in sediments in the Selorejo Reservoir was found successively in the Konto river inlet with a total abundance value of 3.68 particles/gram, then in the tourist area 2.08 particles/gram, in the Kwayangan river inlet 1.56 particles/gram, in the residential part (blendrang) a number of 1.2 particles/gram and outlets 1.12 particles/gram. Each type of microplastic is then counted based on the amount found. The results of the identification of microplastic contamination in waters and sediments in the Selorejo Reservoir found several types of microplastics, namely fibers, fragments, filaments, and films. The dominating type and color of microplastic is black fiber.

Microplastics in the digestive tracts of fish can make their way into the food chain, reaching higher trophic levels, including humans, and potentially causing health issues. The Banjaran River in Banyumas Regency is one such waterway at risk of microplastic pollution. This study aimed to identify the types and abundance of microplastics in fish from the Banjaran River. Sampling was conducted at four strategically chosen stations based on land use, with three repetitions at two-week intervals. Analysis of the type composition and abundance of microplastics in the fish digestive tract using laboratory testing with microscope observations. Four types of microplastics were found in all samples with a predominance of fiber (37%), fragments (31%), pellets (19%), and film (14%). The abundance of microplastics in the fish digestive tract ranges from 12.8-20.5 particles/individual. The highest abundance of microplastics was found in broomstick fish, while the lowest abundance of microplastics was found in broomstick fish.Keywords: Banjaran River; Fish Digestion; Microplastics

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.

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

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.

This research was carried out in March 2020 to identify the type and abundance of microplastics and the relationship between the abundance of microplastics and the size (weight and length) of Telescopium telescopium in the coastal waters of Karimun Island, Riau Islands Province. Tanjung Balai Karimun has densely populated settlements and has many tourist attractions, so it is suspected that a large amount of plastic used is wasted into marine waters and fragmented into microplastics. The method used in this research is the survey method. The results showed that the abundance of microplastics in T.telescopium ranged from 6.9 - 12 particles/individual. The types of microplastics found were fibre, film and fragments, with the dominant type being Fiber. The abundance of fibre type microplastics has a strong relationship with weight and a moderate to length relationship. The abundance of film and fragment microplastics had a weak relationship with weight and length

This study recorded the abundance, characteristics, and distribution of microplastics (MPs) in the surface water in the Banda Sea and Seram Sea. The Banda Sea has known for its complex bathymetry with the shape of a basin in the west and a Sahul Shelf in the east. Due to its unique topography, it controls the water mass exchange in Indonesian waters. The Banda Sea and Seram Sea are dominated by the deep sea with bathymetry of more than 1000 m. Station observation consists of 5 stations in the Banda Sea and 3 stations in the Seram Sea. The microplastic abundance in the surface waters from the Banda Sea and Seram Sea ranged from 4.69 to 22.48 items/L with an average abundance of 14.07 items/L. The highest abundance of MPs was found in Station 1 of Banda Sea due to the closest to Ambon as the capital of Maluku Province. The dominant shape of MPs found such as fibre, fragment, and pellet. The polymer type of MPs found were PET, HDPE, LDPE, PVC, PP, and Nylon. Generally, the abundance of MPs on the surface of the deep-sea area was found lesser than in the coastal area since the MPs distributions are influenced by hydrodynamics and anthropogenic activity.

This research is an explorative research/Land-Based Survey. The purpose of this research is to identify an organism in the Lake Toba water to see organism diversity in the area of Lake Toba, and some factors which influence the kind and diversity of organism in Lake Toba. This research was conducted by using methods of a trap in May 2016 until April 2017 in three regencies of Lake Toba Area, including Samosir, Simalungun, and Porsea Regency. The result of the research showed that the organisms found in the waters of Lake Toba were Plakton, Macrozoobentos, and Nekton. The index of macrozoobenthos diversity in three regencies are categorized into low. The highest value of diversity was in Samosir Regency (1,6) then followed by Tobasa (1,5), and Simalungun (0,43). The value of plankton diversity index in three regencies are; Samosir (2,47), Tobasa (1,41), and Simalungun Regency(1,63). The index of fish diversity in three regencies was categorized into low; Samosir (1,97), Tobasa (1,16), and Simalungun Regency (1,61). In those three districts, there were 25 species of plankton, 12 species of macrozoobenthos and 8 species of fish. The change of the environmental condition influenced the diversity of animal. The research suggests that the need for conservation as the management planning to cope with the environmental condition to maintain the quality of Lake Toba environment.

The Padang Beach Tourism Area is a popular destination in Padang City making it susceptible to contamination by microplastics. From April to June 2023, we sampled seawater and sediment for microplastics from eight stations having varying degrees of human influence, including densely populated areas, river estuaries, tourist areas, and sparsely populated areas. We analyzed the samples to determine abundance, shape, size, color, and composition. Five shapes (fibers, films, fragments, granules, and pellets), seven colors (black, blue, brown, red, transparent, green, and white), and eight compositons (polycarbonate, polypropylene, polyethylene, polysulfone, polyvinyl chloride, polyethylene terephthalate, polystyrene, and polytetrafluoroethylene) were identified and categorized into five size ranges (1-100 µm, 100-300 µm, 300-500 µm, 500-1000 µm, and 1-5 mm). Microplastics abundance in seawater was not significantly different across stations, ranging from 0.064 to 0.229 particles/m3. Microplastic abundance in sediment, was also not significantly different across stations, ranging from 0.151 to 0.387 particles/kg. However, there was a significant difference between the abundance of microplastics in seawater and sediment. The highest abundance of microplastics was in the form of fragments, and there was significant difference from fiber, fragment, pellet, and granule types. In contrast, thre was a significant difference between the abundance of film-type microplastics in seawater and sediment. Overall, microplastic abundance was similar across densely populated areas, river estuaries, and tourist areas and higher than in sparsely populated areas.

Microplastics contamination in aquaculture-rich regions: A case study in Gresik, East Java, Indonesia

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.

An overview of microplastic pollution in the environment over the megacity of Shanghai during 2013–2022

In the present study we collected the Thumbprint emperor (Lethrinus harak) from seven landing sites from the coastal waters around Dar es Salaam and Zanzibar (Tanzania) to (i) quantify and characterize microplastics (MPs) in their digestive tracts and (ii) use previously assessed environmental levels in nearshore surface waters and seabed sediments to determine whether L. harak could be a relevant biomonitor for MP pollution in the region. L. harak (n=387) had an overall frequency of occurrence (FO%) of 48 % and displayed spatial variation between sites with Kunduchi (FO=66.7 %) and Mijimwena (FO=17.1 %) having the highest and lowest FO%, respectively. Fish from Mjimwema had a mean MP content of 0.17 ± 0.38 MPs individual-1 whilst fish from Kizimkazi had the highest MP abundance (1.75 ± 2.33 MPs individual-1). Fibers (overall 64.7 %, range across sites 48–86 %) and fragments (17.9 %, 5–25 %) were the most dominant MP types whilst black (46.9 %, 40–58 %) and blue (22.5%, 7–36 %) MPs were the most common colours. Fish length (ρ= -0.09, p=0.09) or weight (ρ=0.07, p=0.18) did not significantly correlate to MP abundance in fish (Spearman rank correlations). Neither MP occurrence nor abundance was linked to MP concentrations in either surface waters or seabed sediments (Spearman rank correlation), but MPs in the fish better reflected MPs in the sediment compared to surface water (two-way ANOVA on ranked data). Whilst L. harak presents as a promising candidate to monitor MP pollution along the East African coast due to its ecology, overall, it lacks reliability. Nonetheless, the present study fills important knowledge gaps both geographically on the East African Coast and with an underrepresented taxonomic family (Lethrinidae ‘Emporer fishes’).

Microplastics (MPs) are prevalent in coastal environments of South Africa but there is a lack of knowledge about the prevalence and risks of MPs in coastal invertebrates. This study aimed to determine the prevalence, characteristics and ecological risks of MPs ingested by various echinoderm feeding groups. Sampling was conducted during low tide in the summer of 2020 at 14 rocky shores in the Western Cape of South Africa. By sampling various echinoderm feeding types, the abundance and characteristics of MPs (shape, colour, size by using microscopy and polymer type by using a Fourier-transform infrared spectroscopy (FTIR-ATR)) were measured. Potential ecological risks posed by MPs were assessed using hazards of respective polymer types. Mean abundance of MPs from all echinoderms was 9.32 (± 0.76 Standard Error of the Mean (SEM)) MPs/Individual, or based on weight, 1.11 (± 0.09 MPs/g soft tissue wet weight). The abundance of MPs was highest in echinoderms sampled from Kalk Bay (56.41 ± 4.37 MPs/I), with storm water outfall pipes and human activities identified as primary source of MP contamination. Filter-feeding sea cucumbers had the highest MP abundance (21.06 ± 3.03 MPs/I), suggesting that non-selective feeding echinoderms have higher MP uptake rates than other feeding strategy echinoderms. The MPs in echinoderms were mainly black/grey (45%) polyethylene terephthalate (PET) (50%) fibres (93%) that ranged from 1000 to 2000 μm (35%) in size. The potential ecological risk of MPs was highest at Kalk Bay (site 9) due to the prevalence low abundances of Polyvinyl chloride (PVC). This is the first study on MPs in coastal echinoderms of the Western Cape in South Africa and provides a baseline for MPs in echinoderms. The findings are significant because they offer the first indication that MP abundance may differ between echinoderm feeding groups.

The accumulation of microplastics in fish from an important fish farm and mariculture area, Haizhou Bay, China