0
Article Tier 2 Environmental Sources Marine & Wildlife Sign in to save

Abundance, characteristics, and ecological risks of microplastics in the riverbed sediments around Dhaka city

The Science of The Total Environment 2023 42 citations

AI summary Read the abstract

Researchers analyzed riverbed sediments around Dhaka, Bangladesh and found medium-level microplastic pollution dominated by polyethylene, polypropylene, and PET from urban and industrial sources. All sampling sites showed pollution levels above baseline, with ecological risk assessments ranging from medium to very high depending on location. The study fills an important data gap on freshwater microplastic contamination in one of the world's most densely populated urban areas.

Study Type Environmental

Microplastic (MP) pollution has become an escalating problem in Bangladesh due to its rapid urbanization, economic growth, and excessive use of plastics; however, data on MP pollution from fresh water resources in this country are limited. This study investigated microplastics pollution in riverbed sediments in the peripheral rivers of Dhaka, the capital of Bangladesh. Twenty-eight sediment samples were collected from the selected stations of the Buriganga, Turag, and Balu Rivers. Density separation and wet-peroxidation methods were employed to extract MP particles. Attenuated total reflectance-Fourier transform infrared spectroscopy was used to identify the polymers. The results indicated a medium-level abundance of MPs in riverbed sediment in comparison with the findings of other studies in freshwater sediments worldwide. Film shape, white and transparent color, and large-size (1-5 mm) MPs were dominant in the riverbed sediment. The most abundant polymers were polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET). Pollution load index (PLI) values greater than 1 were observed, indicating that all sampling sites were polluted with MPs. An assessment of ecological risks, using the abundance, polymer types, and toxicity of MPs in the sediment samples, suggested a medium to very high ecological risk of MP pollution of the rivers. The increased abundance of MPs and the presence of highly hazardous polymers, namely; polyurethane, acrylonitrile butadiene styrene, polyvinyl chloride, epoxy resin, and polyphenylene sulfide, were associated with higher ecological risks. Scanning electron microscopy (SEM) analysis indicated that the MPs were subjected to weathering actions, reducing the size of MPs, which caused additional potential ecological hazards in these river ecosystems. This investigation provides baseline information on MP pollution in riverine freshwater ecosystems for further in-depth studies of risk assessment and developing strategies for controlling MP pollution in Bangladesh.

More Papers Like This

Article Tier 2

Risk assessment of microplastic pollution in urban lakes and peripheral Rivers of Dhaka, Bangladesh

AI summary Read the abstract

Researchers assessed microplastic abundance and ecological risk in urban lake and river surface water and sediments across Dhaka, Bangladesh. Microplastics were detected at all 19 sites, with polymer hazard quotients indicating elevated ecological risk, particularly in heavily urbanized and industrialized locations.

Article Tier 2

Microplastics in Sitalakhya River: Distribution and Properties Across Land Uses in Dhaka's Peripheral Waterway

AI summary Read the abstract

Researchers investigated microplastic pollution in the water and bed sediments of the Sitalakhya River on the periphery of Dhaka city, sampling four locations representing commercial, residential, industrial, and agricultural land uses and finding microplastic abundances ranging from 20 to 412 items/kg in sediment and 3 to 38 items/100L in water. The study found that land use type significantly influenced both the abundance and physical characteristics of microplastics, with industrial zones exhibiting the highest contamination levels.

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

Microplastic pollution in the water and sediment of the Karnaphuli River, Bangladesh: An ecological risk assessment

AI summary Read the abstract

Researchers assessed the spatial and seasonal distribution of microplastics along the Karnaphuli River in Chattogram, Bangladesh. Microplastic concentrations were higher in sediment than surface water and elevated in downstream locations, with fibers and fragments of PET, polyethylene, and polystyrene being the most common types, and the ecological risk assessment rated the pollution as Category I, indicating a significant pollution load.

Article Tier 2

Evaluating the sources of microplastic contamination and quantifying its abundance in the Balu River, Dhaka, Bangladesh

AI summary Read the abstract

Researchers investigated the sources and abundance of microplastic contamination in the Balu River in Dhaka, Bangladesh. They found that textile and industrial waste were major contributors to microplastic pollution, with fibers being the most common type detected in surface water samples. The study provides baseline data on river microplastic contamination in a densely populated urban area and calls for better waste management practices.

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