Occurrence, polymer composition, and polymer-specific ecological and human health risks of microplastics in the Sundarbans mangrove ecosystem, Bangladesh: An integrated multi-compartment assessment.
Md Ali Hossain Shamim, Jun Wang, Kazi Belayet Hossain, A B M Sadique Rayhan, Md Mazharul Islam, Hongwei Ke, Chunhui Wang, Minggang Cai
{"title":"Occurrence, polymer composition, and polymer-specific ecological and human health risks of microplastics in the Sundarbans mangrove ecosystem, Bangladesh: An integrated multi-compartment assessment.","authors":"Md Ali Hossain Shamim, Jun Wang, Kazi Belayet Hossain, A B M Sadique Rayhan, Md Mazharul Islam, Hongwei Ke, Chunhui Wang, Minggang Cai","doi":"10.1016/j.marenvres.2026.108471","DOIUrl":null,"url":null,"abstract":"<p><p>Microplastic (MP) pollution poses an increasing threat to mangrove dominated estuarine systems, yet comprehensive multi-compartment assessments remain limited in South Asia. However, comprehensive MP assessments linking sources, transport, and risks remain scarce in South Asian mangrove ecosystems. This study investigated the occurrence, characteristics, sources, and risks of MPs in surface water, sediment, fish, and shrimp from three brackish rivers (Pasur, Kholpetua, and Rai) and adjacent shellfish farms within the Sundarbans mangrove ecosystem, Bangladesh. MP concentrations ranged from 50 to 480 items/m<sup>3</sup> in water and 58.55-269.25 items/kg in sediment, with the highest contamination consistently observed in the Pasur River, reflecting intense anthropogenic pressure near the Mongla port region. MPs were detected in all fish (100%) and 93% of shrimp samples, predominantly as fibers (>90%), with gills and gastrointestinal tracts (GIT) showing higher burdens than muscle tissues. Fourier-transform infrared spectroscopy (FT-IR) identified nylon, polypropylene (PP), polyethylene (PE), and polyvinyl chloride (PVC) as the dominant polymers, indicating inputs from fishing gear, textile waste, industrial effluents, and domestic discharge. Bioaccumulation analysis revealed species-specific differences, with Polynemus paradiseus exhibiting the highest accumulation potential. Ecological risk indices (PLI, PHI, and PRI) indicated moderate to high pollution risk at several sites, while estimated annual intake values suggested potential human exposure concerns, particularly for children. Overall, these findings provide a monsoon-season snapshot of MP contamination, offering baseline insights into its distribution, transport, and associated ecological and human health risks in the Sundarbans. As sampling was conducted over a short period, the results should not be considered annual baselines. Long-term seasonal monitoring, along with improved waste management and industrial regulation, is needed to assess temporal variability and establish reliable ecosystem baselines.</p>","PeriodicalId":18204,"journal":{"name":"Marine environmental research","volume":"222 ","pages":"108471"},"PeriodicalIF":3.4000,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Marine environmental research","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1016/j.marenvres.2026.108471","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Microplastic (MP) pollution poses an increasing threat to mangrove dominated estuarine systems, yet comprehensive multi-compartment assessments remain limited in South Asia. However, comprehensive MP assessments linking sources, transport, and risks remain scarce in South Asian mangrove ecosystems. This study investigated the occurrence, characteristics, sources, and risks of MPs in surface water, sediment, fish, and shrimp from three brackish rivers (Pasur, Kholpetua, and Rai) and adjacent shellfish farms within the Sundarbans mangrove ecosystem, Bangladesh. MP concentrations ranged from 50 to 480 items/m3 in water and 58.55-269.25 items/kg in sediment, with the highest contamination consistently observed in the Pasur River, reflecting intense anthropogenic pressure near the Mongla port region. MPs were detected in all fish (100%) and 93% of shrimp samples, predominantly as fibers (>90%), with gills and gastrointestinal tracts (GIT) showing higher burdens than muscle tissues. Fourier-transform infrared spectroscopy (FT-IR) identified nylon, polypropylene (PP), polyethylene (PE), and polyvinyl chloride (PVC) as the dominant polymers, indicating inputs from fishing gear, textile waste, industrial effluents, and domestic discharge. Bioaccumulation analysis revealed species-specific differences, with Polynemus paradiseus exhibiting the highest accumulation potential. Ecological risk indices (PLI, PHI, and PRI) indicated moderate to high pollution risk at several sites, while estimated annual intake values suggested potential human exposure concerns, particularly for children. Overall, these findings provide a monsoon-season snapshot of MP contamination, offering baseline insights into its distribution, transport, and associated ecological and human health risks in the Sundarbans. As sampling was conducted over a short period, the results should not be considered annual baselines. Long-term seasonal monitoring, along with improved waste management and industrial regulation, is needed to assess temporal variability and establish reliable ecosystem baselines.
期刊介绍:
Marine Environmental Research publishes original research papers on chemical, physical, and biological interactions in the oceans and coastal waters. The journal serves as a forum for new information on biology, chemistry, and toxicology and syntheses that advance understanding of marine environmental processes.
Submission of multidisciplinary studies is encouraged. Studies that utilize experimental approaches to clarify the roles of anthropogenic and natural causes of changes in marine ecosystems are especially welcome, as are those studies that represent new developments of a theoretical or conceptual aspect of marine science. All papers published in this journal are reviewed by qualified peers prior to acceptance and publication. Examples of topics considered to be appropriate for the journal include, but are not limited to, the following:
– The extent, persistence, and consequences of change and the recovery from such change in natural marine systems
– The biochemical, physiological, and ecological consequences of contaminants to marine organisms and ecosystems
– The biogeochemistry of naturally occurring and anthropogenic substances
– Models that describe and predict the above processes
– Monitoring studies, to the extent that their results provide new information on functional processes
– Methodological papers describing improved quantitative techniques for the marine sciences.