Plastic pellet pollution in the Aeolian Islands UNESCO site (Italy, Western Mediterranean Sea): results of a comprehensive characterization and monitoring study

: The archipelago of the Aeolian Islands in the Tyrrhenian Sea is a globally important natural laboratory. The archipelago, declared a UNESCO World Heritage Site for its unique geology and biodiversity, offers a unique opportunity to study plastic pollution. This study presents an initiative to assess the occurrence of plastic pellets on the beaches of five Aeolian Islands. It provides an insight into the polymer composition and the effects of degradation. Collected pellets were analyzed using stereomicroscopy and Fourier transform infrared spectroscopy (FTIR). Hierarchical cluster analysis (HCA) based on the results of the FTIR data has proved to be an effective statistical method in identifying different clusters corresponding to different degradation phases of the collected pellets. The infrared analysis identified polyethylene (80%) as the main polymer, with a small amount of polypropylene (20%). It was found that the surfaces of some pellets undergo changes during weathering that alter the polymer surfaces. By combining data on plastic pellets from the Aeolian Islands and surrounding coastal areas, we are gaining a more comprehensive understanding of the distribution patterns of microplastics. The results of the monitoring and characterization are expected to support the developing of waste management and remediation strategies for this environmentally sensitive region.