Researchers at Bangladesh Agricultural University have detected microplastics in five native fish species from Arial Beel in Munshiganj.
The species studied were koi, bata, meni (also known as veda or nandina), gulsha tengra, and punti, with koi showing the highest microplastic load.
Samples were collected from five points—Gadi Ghat, Basurola Danga, Sagar Danga, Baraikhali, and Alampur—during the 2024 monsoon, 2024–25 winter, and 2025 dry season, covering water, sediment, and fish.
In koi, an omnivorous species, muscle tissue contained on average about one microplastic particle per fish across all three seasons, while intestines and gills showed higher counts.
Water samples contained 11 to 31.67 microplastic particles per liter and sediment 12.33 to 127.33 particles per kilogram, with the highest water contamination recorded in the monsoon.
Fourier transform infrared spectroscopy identified that 34–63% of the particles were microfibers, attributed to synthetic fibers from washing clothes, household wastewater, and plastic fishing nets.
Chemical analysis detected polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polycarbonate, materials commonly used in plastic bags, packaging, bottles, and household products.
Lead researcher Prof. Md. Shahjahan said there is no immediate health risk from eating these fish, but long-term accumulation of particles could affect human health, aquatic ecosystems, and food security, possibly manifesting after 25–30 years or in future generations.