Microplastics levels in cultured or harvested mollusks non-depurated and commercially depurated at different times

Microplastics (MPs) are emerging pollutants found worldwide, not only in environmental matrices but also in the food web. The present study aimed to establish better removal rates of MPs in cultivated or harvested edible bivalves currently on the market. Samples of three species (mussels, oysters and wedge clams) were collected from a producer at three different depuration times. The most abundant (>90 %) detected morphology corresponded to fibers. Standard depuration rates were 50 %, 26 % and 26 % reduction of MPs in mussels, oysters and wedge clams, respectively. In turn, extending the depuration treatment did not significantly improve the depuration rate. The total ingestion of MPs through the consumption of these species was estimated for the adult population in a range between 2508 and 4692 items, depending on the depuration stage. This means a yearly mean accumulated consumption of 4.5, 2.4, and 2.7 m of fibers for non-depurated, standard and extended depurated mollusks, respectively.