Abstract:
ABSTRACT
The study investigated the occurrence and distribution of microplastics in the
water, sediment and fishes from the Pra estuary. Samples were collected using
a manta trawl and Ekman grab within sixteen sampling points of 1km apart.
Microplastics (MPs) were categorized into shapes, colour, size and polymer
types using a stereomicroscope and ATR-FTIR spectrometer. A total of 12
species, Gobionellus occidentalis, Ethmalosa fimbriata, Chrysichthys
nigrodigitalus, Elops lacerta, Mugil bananesis, Cynoglossus senegalensis,
Galeoides decadactylus, Sarotherodon melanotheron, Apsilus fuscus,
Pseudotolithus senegalensis Callinectis aminicola, and Penaeus penaeus were
identified to accumulate microplastics. Occurrence of MPs in the
gastrointestinal tract exceeded that of the gills. Microplastics were present in
the vesical tissues of all the shellfishes sampled. The overall mean (± s.d)
density of microplastics in the surface water and sediment were 196,259.84 ±
60168.72 items.km-2 and 116.44 ± 11.31 items.kg-1d.w respectively. The
occurrence of microplastics was significantly higher at S-N (a tributary passing
the Anlo community) along the Pra estuary. Temporally, microplastic
abundance was observed to increase during the early raining season (April)
compared to the other months. Further, the flow velocity had a significant
influence on microplastic distribution in the water column. Transparent and
black fibres, less than 0.5 mm were found to dominate the surface water,
sediment and fish. Polyethylene and Polypropylene were found to be the most
occurring polymer type in the Pra estuary. Hence, there is the need for proper
plastic waste management strategies to reduce the amount of plastics waste
entering into the aquatic environment
