Italian Pellets Watch: First step towards national assessment of resin pellets distribution, characterization and pollutants absorption

Resin pellets, which are highly prone to environmental dispersion, can absorb pollutants such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) once they enter marine environments. Principal aim of the study was to statistically confirm the correlation between pollutant content and the yellowing parameter - indicative of chemical aging of pellets - behind the use of pellets as a cost-effective alternative for chemical pollution assessment in the marine environment. In parallel, we first tested the use of the LIBS (Laser-Induced Breakdown Spectroscopy technique to detect the presence of metals on the surface of pellets. We conducted Italy's first national survey of resin pellets through a citizen science initiative. A total of 2270 pellets were collected from 73 beaches across 13 Italian regions and analyzed based on morphological characteristics, including discolouration, fouling presence, and porosity. From selected subsamples we extracted four PAH and six PCB congeners and examined the surface heavy metal content using LIBS technique. Pollutant concentration values were found to be correlated with the discoloration parameter of yellowing, further validating the use of resin pellets as an effective proxy for environmental pollution in place of traditional methods like mussels or others environmental matrix, as first proposed in the International Pellets Watch (IPW) framework.