Multi-matrix approach to microplastic pollution in the bivalve Donax trunculus, sediment and water along the Mediterranean coasts

Plastic pollution is a widespread issue in marine ecosystems worldwide, and at the basin level, the Mediterranean represents one of the main hotspots for plastic debris. Here, we present MPs pollution levels in the bivalve Donax trunculus, commonly known as wedge clam, considering both young and adult individuals, as well as sediment and water matrices across a national scale, covering the Tyrrhenian, Ionian, and Adriatic coasts of Italy. The aim is to provide an overview of MPs pollution in coastal ecosystems and assess whether wedge clams can act as an early warning sentinel for sandy habitats. Results highlighted that the Adriatic and Ionian coasts exhibited higher MPs levels than the Tyrrhenian coast across all matrices, with MPs pollution predominantly consisting of blue acrylic fibers. D. trunculus proved to be an excellent sentinel for MPs pollution in sediment. The findings also revealed that young individuals had more MPs than adults, highlighting potentially severe harm to the growth of marine organisms. As a commercially valuable species, this study underscores the urgent need to further investigate this issue, especially given its critical implications for both marine ecosystem health and human well-being.