Persistence and potential increasing accumulation of microplastic pollution on the Skikda coast (northeastern Algeria).

This paper describes the microplastic problems on five sandy beaches along the Skikda coastline (southwestern Mediterranean, northeastern Algeria), defining their magnitudes, spatial-temporal distributions, shapes, polymer types, impacts, and potential sources. The data presented in this study were collected during two field surveys in May (spring) and September (autumn/fall) of 2019. Overall, the average abundance of microplastics across all beaches was 6174 items/m² in spring and 6183 items/m² in autumn, representing the highest level of MPs ever reported in Algeria. The most common microplastic types found were fragments, pellets, foams and fibers, accounting for >98 % of the microplastic shapes collected in this study. Our findings highlight the persistence of MPs on the studied beaches and that environmental factors such as currents, wind directions, beaching, sedimentation, dunes, and fragmentation all significantly impact the distribution and accumulation of plastic debris on beaches.