Harmonizing Data for Dietary Microplastic Exposure: Insights into Seafood and Age Specific Risks

Over recent decades, the rapid increase in plastic production has led to heightened concerns about the pervasive presence of microplastics (MPs) in the environment. Defined as particles smaller than 5 mm, MPs are increasingly detected in various food categories, raising questions about human exposure and associated health risks. This study aims to evaluate dietary exposure to MPs, with a specific focus on seafood, and to assess the contribution of various food grou ps to total MP exposure. To address this challenge, we reviewed existing data on MP occurrence in bivalves and crustacea and analyzed findings from a previous study involving 218 food items purchased from mainstream food retailers. We employed exposure assessment techniques to estimate daily MP intake across three age groups (children, adolescents and adults), considering realistic and worst-case scenarios. Special attention was given to aligning and comparing data from diverse sources using standardized methodologies. Our results indicate that adults have an average MP exposure of up to 0.37 MP per kilogram of body weight per day under realistic conditions. In contrast, children experience the highest exposure, reaching 4.19 MP per kilogram of body weight per day in worst-case scenarios. These findings highlight significant variability in exposure levels based on age and dietary habits. This study highlights the critical need for harmonized methodologies to synthesize data from diverse sources, particularly in evaluating seafood as a major contributor to dietary microplastic (MP) exposure. MPs in food may act as vectors, potentially transporting contaminants and allergens, making them more significant for secondary risks than nanoplastics (NPs), which are more concerning due to their distinct toxicological profiles. By improving our understanding of MP ingestion through food, this research provides a foundation for future investigations into exposure sources, associated health risks, and strategies for mitigation. The research that yielded MP occurrence results, was funded by the Belgian Federal Public Service Health, Food Chain Safety and Environment through the contract RT 18/05 Plastic_in_Food. The complementary study and the literature review was done in the scope of IMPTOX project which was funded by The EU s H2020 framework program for research and innovation, grant number 965173 entitled An innovative analytical platform to investigate the effect and toxicity of micro and nanoplastics (MNPs) combined with environmental contaminants on the risk of allergic disease in pre-clinical and clinical studies.