Les microplastiques et leurs additifs dans les produits de la pêche : développements méthodologiques et prévalence

Increase in plastic production since the 1950's in combination with plastic waste mismanagement lead to the presence of plastic particle in terrestrial and marine environment. Plastic particles measuring less than 5 mm, called microplastics, are ingested by a wide range of organisms. The goal of this PhD thesis was to evaluate the microplastic hazard for seafood consumers. firstly, method for digesting seafood tissue without degrading plastic polymer was selected and applications limits were determined for digestion of fish digestive tracts. Concurrently, a Pyrolysis-GC/MS method was optimized, limit of detection were determined and this method was applied on environmental samples. Both methods were used to study microplastics contamination in bivalve and fish species used for human consumption. Bivalve contamination was between 0.15 and 0.74 MP/g of tissue wet weight whereas contaminations in fish were low. Indeed, digestive tracts were contaminated by in mean 0.01 MP/g of tissue wet weight and muscles were contaminated by in mean 0.001 MP/g of tissue wet weight. Lately, leaching of a plastic additive was studied using an in vitro enzymatic model of digestion. However, such phenomenon was not highlighted. Overall, these results will help to standardize the study of microplastics in seafood products.