Assessment of microplastics in water and sediment from Megech river, major tributary to Lake Tana

• Average abundance is more than 1 MP/2L in the river water sample • Average abundance is nearly 2 MP/100g in river sediment sample • Transparent, white, and black color types of MP are more significant • MPs size <0.5mm was predominant in both surface water and sediments Ethiopia is the second largest importer of raw plastic materials in Central and Eastern Africa with fastest-growing plastic industry in the continent. Plastic pollution is a serious problem in the country and the government has started an awareness campaign for its reduction. This work is an initial attempt to evaluate the occurrence, abundance and characterization of microplastics (MPs) in shape, color and size from surface water and sediment of Megech River and its tributaries into Lake Tana, Ethiopia. As a result, the average abundance of MPs in surface water and sediment from 11 sampling sites were 0.55±0.31 items/L and 19.39 ± 11.91 items/Kg respectively. From the obtained total of 137 MP particles, the dominant shape, color and size were fragment (32.9%, 40.63%), transparent (30.17%, 29.69%), and <0.5mm (47%, 47%) for surface water and sediment respectively. A significant difference in MP abundance was observed in the transition from upper rural to urban areas and lower rural, with higher concentrations distributed from urban tributaries to the main Megech River. This pattern is attributed to anthropogenic activities from Gondar city, which the River passes through. These results can be used to augment the current database of MPs pollution and provide useful references for further research.