Effect of polymeric materials on the natural sediment communities of the Mediterranean Sea

Plastic waste and its replacement options introduce various polymer types in marine environments. The influence of polymers on the bacterial communities of surrounding environments remains largely unexplored. Moreover, there exists an apparent paucity of knowledge about the fate of plastic polymers in the sediments of eulittoral sandy beaches. Addressing these knowledge gaps is pivotal for advancing our understanding of the broader ecological consequences of plastic pollution and informing sustainable practices in the face of escalating global plastic production. For this reason, our study aims to assess the effect of the addition of polymeric material on the surrounding sediment bacterial communities of Fetovaia Beach located at Isola d'Elba, Italy. The experiments were set up in a mesocosm bin using PHB and HDPE along with bamboo as a natural biodegradable polymer control. These polymers were exposed to the eulittoral sandy beach conditions of the Mediterranean Sea wherein samples were periodically wetted and dried due to the tidal cycle. After 258 days of exposure, the sediments in contact with the polymers were harvested along with PHB-biofilm and no-contact natural sediments, and the bacterial composition of these samples was elucidated using 16S rDNA analysis.The present study aims to address the following questions: Is the bacterial composition and community structure of sediments altered by the presence of polymers in the environment? How are the functions of sediment bacterial communities affected by the presence of extraneous polymeric material? Do the changes in sediments depend on the type of polymer?