0
Article Tier 2 Detection Methods Environmental Sources Gut & Microbiome Marine & Wildlife Policy & Risk Sign in to save

Characterization, distribution, and risk assessment of microplastic in fish and sediment from the longest river of Bangladesh

Water Environment Research 2025 13 citations

AI summary Read the abstract

Researchers characterized microplastic contamination in fish and sediment from the Brahmaputra River in Bangladesh, the country's longest river. They found microplastics in all fish and sediment samples, with fibers being the most common type, and bottom-dwelling fish species containing more particles than those living near the surface. The study provides important baseline data on freshwater microplastic pollution in a major South Asian river system.

Polymers
Body Systems
Study Type Environmental

Microplastics (particles smaller than 5 mm) are among the most common pollutants in aquatic habitats because they may develop to high densities and can interact with both the abiotic and biotic environments. There is less information available on microplastics in the freshwater systems than there is in the marine environment. This study aims to shed light on the abundance and spatial distribution of microplastics in the Brahmaputra River (Mymensingh) through the utilization of the wet peroxide oxidation isolation technique, supplemented with sodium chloride, to examine fish and sediment specimens collected between December 21, 2022 and January 12, 2023. A total of 26 and 189 microplastic particles were identified in the fish and sediment samples, respectively. Microplastics (MPs) concentrations in fish gut ranged from 0.5 ± 0.7 to 1.67 ± 0.58 MPs individual-1. The most prevalent shape found in fish stomachs was fiber (46%), and the most common color was transparent (32%). Sizes 0.5-1 mm (1.6 ± 0.74) had the most microplastics. This study found that fishes from the demersal (3.25 ± 1.7) zone had more MPs than the benthopelagic (2.5 ± 0.58) and pelagic (1.5 ± 0.7) zones. Omnivorous fishes (54%) consumed more microplastics than carnivorous (31%, 2.6 ± 0.58) and herbivorous fishes (15%,1.33 ± 0.94). Microplastic consumption had a moderate correlation with fish body weight (r = 0.34), length (r = 0.46), and gastrointestinal content (r = 0.45). The MPs per kilogram of Brahmaputra River bed sediment ranged from 8 to 31, with a mean abundance of 18.9 ± 7.01 particles kg-1. The most common shape identified in this study was fragments (52%) and 33% of sediment microplastics were blue in color. Microplastics were most abundant in the 1-3 m-meter size class. Fourier transform infrared spectroscopy (FTIR) showed that polypropylene (PP) was the most prevalent MP in both fish (34%) and sediment (40%) samples. In this study, the Pollution load index (PLI) for each sampling site is <10, with the highest value found for station 2(1.97 ± 0.49), regarded as risk category I. This study's results will be useful for future research on microplastics in freshwater environments. PRACTITIONER POINTS: Abundance and distribution of microplastics were determined from the longest river of Bangladesh. The structural properties of microplastics were characterized using ATR-FTIR spectroscopy. Pollution load index (PLI) of microplastics was investigated.

More Papers Like This

Article Tier 2

Microplastics in Some Freshwater Wild and Farmed Fish Species of Bangladesh

AI summary Read the abstract

Researchers found microplastics in multiple freshwater fish species from both wild river populations and farmed fish in Bangladesh, with fibers being the dominant type. The study highlights the widespread contamination of both wild and farmed fish in major Bangladeshi rivers, with implications for human dietary exposure through fish consumption.

Article Tier 2

Prevalence of microplastics in commonly consumed fish species of the river Old Brahmaputra, Bangladesh

AI summary Read the abstract

Researchers found microplastics in nearly 59% of edible fish from Bangladesh's Old Brahmaputra river, with polyethylene fibers and pellets dominating, and ingestion rates linked to fish size, feeding behavior, and downstream location.

Article Tier 2

Abundance, distribution and composition of microplastics in sediment and fish species from an Urban River of Bangladesh

AI summary Read the abstract

Researchers examined microplastic contamination in both river sediment and fish from the Turag River in Bangladesh, which separates an industrial city from the capital Dhaka. They found microplastics in all sediment and fish gut samples, with fragment-type particles dominating in sediment and fibers most common in fish. The study highlights that urban rivers in densely populated areas can serve as significant conduits of microplastic exposure for both aquatic life and the people who consume river fish.

Article Tier 2

Abundance, characteristics and variation of microplastics in different freshwater fish species from Bangladesh

AI summary Read the abstract

Researchers examined 48 freshwater fish from 18 species in Bangladesh and found microplastics in the digestive tracts of over 73% of the fish studied. Fibers were the most common shape, and the plastics were primarily polyethylene and polypropylene-based polymers. Bottom-dwelling fish contained more microplastics than those living higher in the water column, suggesting that contaminated sediments are a significant source of exposure for freshwater species.

Article Tier 2

Ecological risk assessment of microplastics contamination in water, sediment and native fish species of the Brahmaputra River, India

AI summary Read the abstract

Researchers assessed microplastic contamination across water, sediment, and seven native fish species in the Indian stretch of the Brahmaputra River, finding water concentrations of 140–420 particles/m³ and sediment loads of 13–53 particles/kg, with polymer hazard indices reaching the highest risk category at multiple sites due to polyurethane and PVC particles—providing the first ecological risk baseline for this major Himalayan river.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper