CEST2025

The project BIOPLAST4SAFE, titled "Biomonitoring of biodegradable micro and nanoplastics: from the environment to humans in a one health perspective", promotes the study of characteristics, fate and potential (eco)toxicological effects of plastics, with a specific focus on biodegradable polymers as a potential EU strategy for mitigating plastic pollution. Within this project the feedback from different marine organisms to the plastic threat, mainly microplastics, has been explored. These synthetic organic polymer particles differing in size, shape, surface texture, chemical composition (polymers and additives) and specific density may affect the exposed biota in a variety of ways (e.g., reduced food uptake, lower energy reserves, affected physiological functions, effects at organism and population levels). In addition, microplastics affect the surrounding environment, being vectors of chemical and biological agents transferring pollutants, invasive species and pathogens in the environment. In this contest, biological effects of microplastics obtained by fragmentation of biodegradable (e.g., polylactic acid - PLA) and non-biodegradable (e.g., polypropylene - PP) products were studied using s battery of marine species, from different taxonomic and trophic levels. Here we review and compare the first results related to the ecotoxicological effects of PP and PLA, calculating Effect Concentrations (ECs), while Predicted No Effect Concentrations (PNECs) values were derived from the EC50s, according to the ECHA guideline (2008). Some sublethal and lethal effects were observed in representative organisms of the food web as producers, consumers and decomposers, in acute and chronic exposures. Furthermore, PLA and PP showed similar ecotoxicity, speculating about the effectiveness of biodegradable polymers in mitigating plastic pollution. In conclusion, further microplastic ecotoxicity assessment are needed, preferably including at least three trophic levels, to support an Environmental Risk Assessment (ERA) procedure of microplastics.