Detecting the route of Mediterranean Litter, tracing back natural volcanic pumice

Major storms in the Mediterranean Sea play a key role in redistributing floating debris along coastal and marine environments. The relationship between the action of large waves, strong winds, litter fate and redistribution is not well known. This study focuses on the understanding of beach macro litter (≥ 2.5 cm) dynamics in the Ionian Sea. The novelty of this project is the use of a natural geological analogue of floating plastic, to investigate the dispersion pattern and source area of pollutants. Floating pumice, with a specific chemistry, represents the best proxy to trace the effect of a major storm event like the Cyclone Harry, 16-23 January 2026, along the southern Italian coasts of Sicily, Calabria, Basilicata and Puglia. Pumice is a highly vesicular volcanic rock characterized by low density and high buoyancy, allowing it to float and can be transported over long distances by sea currents and is commonly found in this area. The study of its chemical composition and provenance are in progress. A total of 28 beaches and 1 point bar deposit in the Neto River were surveyed, combining systematic sampling of surficial sediments and plastics and documenting with photographs post storm depositional features. Field observations revealed the presence of a variety of light floating anthropogenic litter (plastic debris, nets, toys, lighters, beach umbrella tip, straws, PET and PE bottles, polystyrene, writing pens, expanded clay balls, aluminum cans, tanks, metal caps, light bulbs, shoes and ropes) mixed with natural materials (vegetal remains, fresh and burnt wood, seaweed balls and white pumice). Marine pollution by anthropogenic litter and floating macro-debris observed during this campaign, are generated by human activities, and redistributed due to natural drivers as wind and surface circulation. This pollution poses a major concern due to its impact on the health of residents and on tourism in these regions.