Patterns and implications of plastic accumulation in mangrove ecosystems and sandy beaches in Western and Central regions of Ghana, West Africa

Plastic pollution has become increasingly apparent in sandy beach zones and aquatic environments, creating more than just visual pollution. Impacts are observed in many environmental and social levels, including the fishing communities that depend on the coastal environment for their livelihoods. Plastic pollution was assessed on the sandy beaches and mangroves of Ghana's Western and Central regions. The study's objective was to determine the composition, abundance and sources of plastic litter at four different sites during the wet and dry seasons. Samples were collected from within 50 cm² quadrats placed randomly along four transects at each site. Plastic litter was classified according to the OSPAR guide. A total of 1895 plastic litter items with a combined weight of ~ 3000 g, representing 30 plastic categories, were collected. The average number and weight of plastic litter items were 19.73 ± 31.37 number of plastics per 50 cm² and 32.59 ± 45.47 g per 50 cm². The minimum and maximum plastic litter items were 0 to 159/50 cm². The highest amount of plastic litter was found in Ghana's Central region. The total plastic litter weight is the variable that present statistical difference between the wet and dry season period. Bags, bottles, and fragments were the most common plastic items found, with 70% of the plastic litter being land-based, with the most frequent polymer types found in this study being polyethylene (~ 54%) and polypropylene (~ 20%). Mangrove regions act as sinks, specifically trapping plastic bags, contrary to the sandy beach areas, which mainly comprise plastic bottles that accumulate in these regions. Regions that have numerous communities, or are urbanised centres, tend to have higher levels or plastic litter. West Africa generally has poor waste management, absence of safe drinking water, and high levels of single-use plastics which are some of the main reasons for increased levels of plastic litter specifically in Ghana. Urgent actions are needed to prevent, mitigate and control plastic pollution in Ghana and the wider region.