The Plastic Signature: Microplastic Ingestion and Phthalate Exposure in Parapenaeus longirostris from Three Tyrrhenian Sites (Mediterranean Sea)

Microplastic pollution is pervasive in marine ecosystems and poses agrowing threat to marine organisms and human health. This studysimultaneously investigates microplastic ingestion and phthalateexposure in Parapenaeus longirostris, a commercially valuable andecologically relevant Mediterranean crustacean occupying an intermediatetrophic position. Specimens were collected from three coastal areas inthe central Tyrrhenian Sea (Western Mediterranean): near the Tiber Rivermouth, one of the most polluted rivers in Italy, and two additionalsites to the north and south. The frequency of individuals with ingestedmicroplastics varied among locations: 78\% near the Tiber River, 64\% atsite S, and 38\% at site N, reflecting anthropogenic pressure gradients.Analyses confirmed the lower occurrence at site N, indicating higheringestion near land-based pollution sources. Ingested microplasticpolymer types varied among sites, reflecting location-specificcontamination. Phthalates were present in shrimp muscle at all sites(5-1122 ng/g w.w.) with the highest average concentration (68.26 +/-55.74 ng/g) at the site with the highest microplastic ingestion.Although no statistical correlation was found, the similar spatialdistribution of microplastics and phthalates suggests a potential linkinfluenced by local pollution and individual variability. These findingsprovide novel evidence of microplastic and phthalate contamination in P.longirostris, highlighting its role as a trophic connector mediatingcontaminant transfer through the food web. While current levels suggestno potential risk to human health, continued monitoring and furtherstudies on exposure along trophic pathways are recommended.