Assessing Microplastic Contamination in Beach Sediments Along the Eastern Algerian Coast: Distribution Patterns, Abundance, and Potential Origins

Microplastics have garnered global attention due to their widespread presence in the environment, significant ecological impacts, and potential human health risks. This study was conducted in the Gulf of Bejaia (Algeria), focusing on three representative beaches: Sidi Ali Labher, Aokas, and Oueddas. Sampling was carried out between April and May 2024 across 100 m 2 transects at each site, subdivided into 50 cm × 50 cm quadrats, yielding 20 replicates under calm weather conditions. Microplastics (MPs) were separated using NaCl flotation and vacuum filtration on gridded cellulose ester filters. Quantitative analyses included MPs density (items/m 2 ), ANOVA for abundance and size differences, and visualizations via Python libraries. Three indices were computed: the Microplastics Pollution Index (MPPI), the Pellets Pollution Index (PPI), and the Fibers Ingestion Potential Index (FIPI). The distribution of MP types showed that fragments were the most prevalent, followed by fibers, foams, films, and pellets. The MPPI indices revealed high abundance at Aokas (MPPI total = 17.18), moderate abundance at Sidi Ali Lebhar (MPPI total = 9.28), and low abundance at Oueddas (MPPI total = 4.22). The FIPI values for Aokas, Sidi Ali Labher, and Oueddas were 0.09, 0.10, and 0.11, respectively, indicating minimal to low potential for fiber pollution from beaches. This study highlights the significant variation in microplastic distribution across the studied beaches and suggests that fibers ingested by biota in these regions are not predominantly from beach pollution.