This study examined the occurrence of microplastics (MPs) in the gastrointestinal tract (GIT) of 384 fishes classified into four species from 11 sites in 2022 from the southern part of the Caspian Sea. GITs of fishes were collected and digested in H2O2 and KOH at 45 °C for 72 h. After filtration, extracted MPs were observed under a stereomicroscope, and selected MP particles were identified using FTIR. Presence of MPs was 68.98% in the GIT of the investigated fish. The mean abundance of MPs was 5.9 ± 0.9 MPs/GIT in Rutilus kutum, 9.2 ± 1.2 MPs/GIT in Chelon auratus, 3.6 ± 0.7 MPs/GIT in Alosa braschnikowi, and 2.7 ± 0.5 MPs/GIT in Vimba vimba. The predominant form of MPs was fiber (58.21%), followed by fragment (34.77%). Black (34.4%), white (19.07%), and blue (14.58%) were the most frequently detected colors of MPs. Overall, 6 MP polymers were identified, dominantly polypropylene (42.86%), polystyrene (17.86%), and cellophane (14.28%). The western part of the Caspian Sea (mostly tourist spots and urban areas) showed more MP pollution in fish compared to the eastern part. Polymer hazard index (PHI) revealed alarming microplastic contamination in the southern Caspian Sea. The PHI value of the present study showed that PES (PHI = 8403.78) and PS (PHI = 535.80) were "Extreme danger" and "Danger" risk categories, respectively.

Department of Aquaculture Faculty of Fisheries Munzur University TR62000 Tunceli Turkey

Department of Fisheries Faculty of Agriculture and Natural Resources Gonbad Kavous University P O box 163 Gonbad Kavous Iran

Department of Fisheries Faculty of Marine Science and Technology University of Hormozgan Bandar Abbas Iran

Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of Hydrogenases Research Institute of Fish Culture and Hydrobiology University of South Bohemia in Ceske Budejovice Zatisi 728 2 389 25 Vodnany Czech Republic

Offshore Water Research Center Education and Extension Organization Iranian Fisheries Science Research Institute Agricultural Research Chabahar Iran

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Abadi ZTR, Abtahi B, Grossart HP, Khodabandeh S (2021) Microplastic content of Kutum fish, Rutilus frisii kutum in the southern Caspian Sea. Sci Total Environ 752:141542

Andrady AL (2017) The plastic in microplastics: a review. Mar Pollut Bull 119(1):12–22

Avio CG, Gorbi S, Regoli F (2015) Experimental development of a new protocol for extraction and characterization of microplastics in fish tissues: first observations in commercial species from Adriatic Sea. Mar Environ Res 111:18–26

Bagheri T, Gholizadeh M, Abarghouei S, Zakeri M, Hedayati A, Rabaniha M, Aghaeimoghadam A, Hafezieh M (2020) Microplastics distribution, abundance and composition in sediment, fishes and benthic organisms of the Gorgan Bay, Caspian sea. Chemosphere 257:127201

Bessa F, Barría P, Neto JM, Frias JP, Otero V, Sobral P, Marques JC (2018) Occurrence of microplastics in commercial fish from a natural estuarine environment. Mar Pollut Bull 128:575–584

Bohluly A, Esfahani FS, Namin MM, Chegini F (2018) Evaluation of wind induced currents modeling along the Southern Caspian Sea. Cont Shelf Res 153:50–63

Borrelle SB, Ringma J, Law KL, Monnahan CC, Lebreton L, McGivern A, Murphy E, Jambeck J, Leonard GH, Hilleary MA, Eriksen M (2020) Predicted growth in plastic waste exceeds efforts to mitigate plastic pollution. Science 369(6510):1515–1518

Chen MC, Chen TH (2020) Spatial and seasonal distribution of microplastics on sandy beaches along the coast of the Hengchun Peninsula, Taiwan. Mar Pollut Bull 151:110861

de Vries AN, Govoni D, Árnason SH, Carlsson P (2020) Microplastic ingestion by fish: Body size, condition factor and gut fullness are not related to the amount of plastics consumed. Mar Pollut Bull 151:110827

do Ivar Sul JAI, Costa MF (2014) The present and future of microplastic pollution in the marine environment. Environ Pollut 185:352–364

Fang C, Zheng R, Chen H, Hong F, Lin L, Lin H, Guo H, Bailey C, Segner H, Mu J, Bo J (2019) Comparison of microplastic contamination in fish and bivalves from two major cities in Fujian province, China and the implications for human health. Aquaculture 512:734322

Free CM, Jensen OP, Mason SA, Eriksen M, Williamson NJ, Boldgiv B (2014) High-levels of microplastic pollution in a large, remote, mountain lake. Mar Pollut Bull 85:156–163. https://doi.org/10.1016/j.marpolbul.2014.06.001 DOI

Ghayebzadeh M, Aslani H, Taghipour H, Mousavi S (2020) Contamination of the Caspian Sea Southern coast sediments with microplastics: a marine environmental problem. Mar Pollut Bull 160:111620

Ghayebzadeh M, Taghipour H, Aslani H (2021) Abundance and distribution of microplastics in the sediments of the estuary of seventeen rivers: Caspian southern coasts. Mar Pollut Bull 164:112044

Gholizadeh M, Cera A (2022) Microplastic contamination in the sediments of Qarasu estuary in Gorgan Bay, south-east of Caspian Sea, Iran. Sci Total Environ 838:155913

Gholizadeh M, Shadi A, Abadi A, Nemati M, Senapathi V, Karthikeyan S (2023) Abundance and characteristics of microplastic in some commercial species from the Persian Gulf, Iran. J Environ Manag 344:118386

Gholizadeh M, Shadi A, Abadi A, Nemati M, Senapathi V, Karthikeyan S, Kulandaisamy P (2024) Exploring the microplastic pollution: unveiling origins and varieties in coastal sediments and waters of the Bushehr Province, Persian Gulf, Iran. Mar Pollut Bull 198:115939

Graca B, Szewc K, Zakrzewska D, Dołęga A, Szczerbowska-Boru-chowska M (2017) Sources and fate of microplastics in marine and beach sediments of the Southern Baltic Sea—a preliminary study. Environ Sci Pollut Res 24(8):7650–7661. https://doi.org/10.1007/s11356-017-8419-5 DOI

Güven O, Gökdağ K, Jovanović B, Kıdeyş AE (2017) Microplastic litter composition of the Turkish territorial waters of the Mediterranean Sea, and its occurrence in the gastrointestinal tract of fish. Environ Pollut 223:286–294

Hasan MM, Rasul MG, Jahirul MI, Khan MMK (2023) Characterization of pyrolysis oil produced from organic and plastic wastes using an auger reactor. Energy Conver Manag 278:116723

Hosseinpour A, Chamani A, Mirzaei R, Mohebbi-Nozar SL (2021) Occurrence, abundance and characteristics of microplastics in some commercial fish of northern coasts of the Persian Gulf. Mar Pollut Bull 171:112693

Jaafar N, Azfaralariff A, Musa SM, Mohamed M, Yusoff AH, Lazim AM (2021) Occurrence, distribution and characteristics of microplastics in gastrointestinal tract and gills of commercial marine fish from Malaysia. Sci Total Environ 799:149457

Jafari N (2010) Review of pollution sources and controls in Caspian Sea region. J Ecol Nat Environ 2(2):025–9

Jeyasanta KI, Sathish N, Patterson J, Edward JP (2020) Macro-, meso-and microplastic debris in the beaches of Tuticorin district, South-east coast of India. Mar Pollut Bull 154:111055

Karami A, Golieskardi A, Choo CK, Romano N, Ho YB, Salamatinia B (2017) A high-performance protocol for extraction of microplastics in fish. Sci Total Environ 578:485–494. https://doi.org/10.1016/j.scitotenv.2016.10.213 DOI

Konechnaya O, Lüchtrath S, Dsikowitzky L, Schwarzbauer J (2020) Optimized microplastic analysis based on size fractionation, density separation and μ-FTIR. Water Sci Technol 81(4):834–844

Krüger O, Kalbe U, Meißner K, Sobottka S (2014) Sorption effects interfering with the analysis of polycyclic aromatic hydrocarbons (PAH) in aqueous samples. Talanta 122:151–156

Landrigan PJ, Stegeman JJ, Fleming LE, Allemand D, Anderson DM, Backer LC, Brucker-Davis F, Chevalier N, Corra L, Czerucka D, Bottein MY (2020) Human health and ocean pollution. Ann Global Health 86(1):151

Laskar N, Kumar U (2019) Plastics and microplastics: a threat to environment. Environ Technol Innovat 14:100352

Li WC, Tse HF, Fok L (2016) Plastic waste in the marine environment: a review of sources, occurrence and effects. Sci Total Environ 566–567:333–349

Liboiron F, Ammendolia J, Saturno J, Melvin J, Zahara A, Richárd N, Liboiron M (2018) A zero percent plastic ingestion rate by silver hake (Merluccius bilinearis) from the south coast of Newfoundland, Canada. Mar Pollut Bull 131:267–275

Lithner D, Larsson Å, Dave G (2011) Environmental and health hazard ranking and assessment of plastic polymers based on chemical composition. Sci Total Environ 409(18):3309–3324

Lusher AL, Welden NA, Sobral P, Cole M (2017) Sampling, isolating and identifying microplastics ingested by fish and invertebrates. Anal Methods 9:1346–1360

Lusher A (2015) Microplastics in the marine environment: distribution, interactions and effects. Marine anthropogenic litter, pp 245–307

Maaghloud H, Houssa R, Ouansafi S, Bellali F, El Bouqdaoui K, Charouki N, Fahde A (2020) Ingestion of microplastics by pelagic fish from the Moroccan Central Atlantic coast. Environ Pollut 261:114194

Manshoven S, Smeets A, Arnold M, Mortensen ZF (2021) Plastic in textiles: potentials for circularity and reduced environmental and climate impacts. European Topic Centre Waste and Materials in a Green Economy. https://www.eionet.europa.eu/etcs/etc-wmge/products/etc-wmge-reports/plastic-in-textiles-potentialsfor-circularityand-reduced-environmental-and-climate-impacts

Mataji A, Taleshi MS, Balimoghaddas E (2020) Distribution and characterization of microplastics in surface waters and the southern Caspian Sea coasts sediments. Arc Environ Cont Toxicol 78:86–93

McNeish RE, Kim LH, Barrett HA, Mason SA, Kelly JJ, Hoellein TJ (2018) Microplastic in riverine fish is connected to species traits. Sci Rep 8(1):11639

Mehdinia A, Dehbandi R, Hamzehpour A, Rahnama R (2020) Identification of microplastics in the sediments of southern coasts of the Caspian Sea, north of Iran. Environ Pollut 258:113738

Murphy F, Russell M, Ewins C, Quinn B (2017) The uptake of macroplastic & microplastic by demersal & pelagic fish in the Northeast Atlantic around Scotland. Mar Pollut Bull 122(1–2):353–359

Naji A, Esmaili Z, Khan FR (2017) Plastic debris and microplastics along the beaches of the Strait of Hormuz, Persian Gulf. Mar Pollut Bull 114(2):1057–1062

Naji A, Azadkhah S, Farahani H, Uddin S, Khan FR (2021) Microplastics in wastewater outlets of Bandar Abbas city (Iran): a potential point source of microplastics into the Persian Gulf. Chemosphere 262:128039

Nematollahi MJ, Moore F, Keshavarzi B, Vogt RD, Saravi HN, Busquets R (2020) Microplastic particles in sediments and waters, south of Caspian Sea: frequency, distribution, characteristics, and chemical composition. Ecotoxicol Environ Sa 206:111137

Nematollahi MJ, Keshavarzi B, Moore F, Esmaeili HR, Saravi HN, Sorooshian A (2021) Microplastic fibers in the gut of highly consumed fish species from the southern Caspian Sea. Mar Pollut Bull 168:112461

Nematollahi MJ, Keshavarzi B, Mohit F, Moore F, Busquets R (2022) Microplastic occurrence in urban and industrial soils of Ahvaz metropolis: a city with a sustained record of air pollution. Sci Total Environ 819:152051

Nithin A, Sundaramanickam A, Iswarya P, Babu OG (2022) Hazard index of microplastics contamination in various fishes collected off Parangipettai, Southeast coast of India. Chemosphere 307:136037

Ory NC, Sobral P, Ferreira JL, Thiel M (2017) Amberstripe scad Decapterus muroadsi (Carangidae) fish ingest blue microplastics resembling their copepod prey along the coast of Rapa Nui (Easter Island) in the South Pacific subtropical gyre. Sci Total Environ 586:430–437

Park H, Park B (2021) Review of microplastic distribution, toxicity, analysis methods, and removal technologies. Water 13:2736

Pazos RS, Maiztegui T, Colautti DC, Paracampo AH, Gómez N (2017) Microplastics in gut contents of coastal freshwater fish from Río de la Plata estuary. Mar Pollut Bull 122(1–2):85–90

Peters CA, Thomas PA, Rieper KB, Bratton SP (2017) Foraging preferences influence microplastic ingestion by six marine fish species from the Texas Gulf Coast. Mar Pollut Bull 124(1):82–88

Ranjani M, Veerasingam S, Venkatachalapathy R, Mugilarasan M, Bagaev A, Mukhanov V, Vethamony PJMPB (2021) Assessment of potential ecological risk of microplastics in the coastal sediments of India: a meta-analysis. Mar Pollut Bull 163:111969

Rasta M, Khodadoust A, Rahimibashar MR, Taleshi MS, Sattari M (2023) Microplastic pollution in the gastrointestinal tract and gills of some teleost and sturgeon fish from the Caspian Sea, Northern Iran. Environ Toxicol Chem 42(11):2453–2465

Roch S, Friedrich C, Brinker A (2020) Uptake routes of microplastics in fishes: practical and theoretical approaches to test existing theories. Sci Rep 10(1):3896

Rochman CM, Browne MA, Halpern BS, Hentschel BT, Hoh E, Karapanagioti HK, Rios-Mendoza LM, Takada H, Teh S, Thompson RC (2013) Classify plastic waste as hazardous. Nature 494(7436):169–171

Rochman CM, Tahir A, Williams SL, Baxa DV, Lam R, Miller JT, Teh FC, Werorilangi S, Teh SJ (2015) Anthropogenic debris in seafood: Plastic debris and fibers from textiles in fish and bivalves sold for human consumption. Sci Rep 5:14340

Rummel CD, Löder MG, Fricke NF, Lang T, Griebeler EM, Janke M, Gerdts G (2016) Plastic ingestion by pelagic and demersal fish from the North Sea and Baltic Sea. Mar Pollut Bull 102(1):134–141

Sathish MN, Jeyasanta I, Patterson J (2020) Occurrence of microplastics in epipelagic and mesopelagic fishes from Tuticorin, South-east coast of India. Sci Total Environ 720:137614

Talbot R, Chang H (2022) Microplastics in freshwater: a global review of factors affecting spatial and temporal variations. Environ Pollut 292:118393

Thushari GGN, Senevirathna JDM (2020) Plastic pollution in the marine environment. Heliyon 6(8):e04709

Uddin S, Fowler SW, Saeed T (2020) Microplastic particles in the Persian/Arabian Gulf–a review on sampling and identification. Mar Pollut Bull 154:111100

Walker TR, Wang L, Horton A, Xu EG (2022) Micro (nano) plastic toxicity and health effects: Special issue guest editorial. Environ Int 170:107626

Wieczorek AM, Morrison L, Croot PL, Allcock AL, MacLoughlin E, Savard O, Brownlow H, Doyle TK (2018) Frequency of microplastics in mesopelagic fishes from the Northwest Atlantic. Front Mar Sci 5:39

Wright SL, Thompson RC, Galloway TS (2013) The physical impacts of microplastics on marine organisms: a review. Environ Pollut 178:483–492

Zakeri M, Naji A, Akbarzadeh A, Uddin S (2020) Microplastic ingestion in important commercial fish in the southern Caspian Sea. Mar Pollut Bull 160:111598

Zazouli M, Nejati H, Hashempour Y, Dehbandi R, Fakhri Y (2022) Occurrence of microplastics (MPs) in the gastrointestinal tract of fishes: a global systematic review and meta-analysis and meta-regression. Sci Total Environ 815:152743

Unveiling Microplastics in Commercial Brackish Water Fishes from the Lower Meghna River Estuary of Bangladesh