A Comprehensive Identification, Distribution and Health Risk Assessment of Microplastics in Natural Mussels from the Shoreline of the Sea of Marmara, Türkiye

Microplastics (MPs) have become a global issue due to their potential adverse effects on sustainable marine resources and human health. In this study, MP pollution was investigated using natural mussels from all shelf regions of the SoM (Sea of Marmara), which is under the influence of many pollutant sources. A total of 322 mussels were collected along the entire coastline, and MP analyses were performed on these mussels. Mussel tissues were digested using a KOH solution to separate the MPs. Following extraction, the samples were filtered and the particles remaining on top were examined physically and chemically. In the study, the highest values were detected in samples taken both from locations under anthropogenic influence, especially from points close to where rivers flow. Across all the samples, the most predominant shape was fiber (61.08%), color was blue (57.87%) and size was (<0.5 mm) (62.55%). FTIR analysis shows that PE is the most common polymer type (44%). Calculated on the basis of 100 g of daily consumption, the annual ingestive exposures to MPs were found to be 1940, 342, 41 and 39 items for children, adolescents, female adults and male adults, respectively. As a result of a detailed risk assessment related to chronic daily intake (CDI) and microplastic carcinogenic risk (MPCR), it was determined that children are the most vulnerable group exposed to MPs and that these seafood products should be consumed with caution by children to prevent potential hazards. Additionally, it has been determined that the southern shelf and the Çanakkale Strait are the areas under the most intense pollution pressure according to the calculated MPCf and MPLI values. These findings are very relevant in terms of taking practical steps to take plans and actions to prevent contamination in the SoM and ensure the sustainability of food safety in the consumption of products obtained from the sea.