Microplastics prevalence in water, sediment and two economically important species of fish in an urban riverine system in Ghana

Urban riverine systems serve as conduits for the transport of plastic waste from the terrestrial dumpsites to marine repositories. This study presented data on the occurrence of microplastics in water, sediment, Bagrid Catfish (Chrysichthys nigrodigitatus) and Black-chinned Tilapia (Sarotherodon melanotheron) from the Densu River, an urban riverine system in Ghana. Microplastics were extracted from the samples collected from both the lentic and lotic sections of the river. The results indicated widespread pollution of the Densu River with microplastics in all the compartments studied. The average numbers of microplastic particles deposited in the Dam (2.0 +/- 0.58) and Delta (2.50 +/- 0.48) sections of the river were not affected by the differences in their hydrology. However, the stagnant water system of the Dam promoted the floating of larger-sized microplastics while the flowing waters of the Delta did not show any selectivity in the deposition of microplastics between sediment and the water column. The number of microplastics ingestions by the Bagrid Catfish (2.88 +/- 2.11) was similar to the Black-chinned Tilapia (2.38 +/- 1.66) but both species ingested lower numbers of microplastics than reported for marine fish species in coastal Ghana.

Automated summary

This study revealed the widespread occurrence of microplastics in water, sediment, Bagrid Catfish, and Black-chinned Tilapia from the urban riverine system of Densu River in Ghana. The stagnant water system of the Dam promoted the floating of larger-sized microplastics, while the flowing waters of the Delta did not show any selectivity in the deposition of microplastics. The number of microplastics ingested by the two fish species studied was lower compared to marine fish species in coastal Ghana.