Microplastics in Ghanaian coastal lagoon sediments: Their occurrence and spatial distribution

Abstract

Each year millions of tonnes of plastic are produced worldwide and around 8 million tons are deposited into our marine environment. Rivers comprise the major conduit for plastic transport with their deltas, estuaries and coastal lagoons being the key interface between lotic aquatic and the oceanic environment. However, we have very little knowledge of the role of coastal lagoons in the plastic pollution pathways. We present the spatial and temporal distribution and abundance of microplastics in sediments from two coastal lagoons in Ghana, West Africa. Sediment cores were taken from Mukwei Lagoon, Kpeshie Lagoon and from the mangroves at Kpeshie Lagoon; areas approximately 5-15km East from the centre of Accra. Microplastics were detected in all samples with a decreasing trend recorded from West to East. All three sites recorded a similar depth profile for plastics: after an initial increase from the surface samples, there was a significant decrease in microplastic concentrations with depth.