Investigating Microplastics in the Mediterranean Coastal Areas – Case Study of Al-Hoceima Bay, Morocco

The issue of microplastics pollution is gaining increasing attention as a global environmental concern. These tiny particles, measuring no more than 5 mm in size and coming in various shapes, can affect all types of marine eco-systems as they are easily consumed by a wide range of marine species. Al-Hoceima Bay, with its semi-enclosed nature and heavily affected anthropized coastline, was chosen as the study area for this research. The main objective was to investigate the presence of various microplastic types in Al-Hoceima Bay by implementing a sampling strategy along the coastline. This comprehensive approach was applied on a local scale within the bay (located in the northwest Mediterranean). Three stations were established in the bay, each located at different levels: the supralittoral, medilittoral and interlittoral. Microplastics were collected from these locations and classified into four categories based on their abundance. Digital microscopy was used to count the plastic particles and they were identified by Fourier transform-attenuated total reflectance infrared spectroscopy (ATR-FTIR). Results showed a higher presence of microplastics in water at 114 particles/L compared to sediment at 70 particles/L. The classification of samples revealed fibers as the most prevalent form, followed by fragments and films being the least commonly found. The abundance of fibers was found to be higher in water 90%, while in sediment it was 31%, however, fragments and leaves were found in higher concentrations in sediment. Polypropylene and polyethylene were identified as the major polymers used in the microplastics analyzed.