Quantifying microplastic translocation from feed to the fillet in European sea bass Dicentrarchus labrax

Uptake of microplastic (MP) particles has been detected in a large number of marine organisms, and humans may consequently be exposed to high MP levels in consumed seafood. Yet there remains a dearth of knowledge regarding uptake into commercially important finfish and tissues (fillets) most commonly consumed by humans. The current study detected translocation of MP into the fillet of European seabass (Dicentrarchus labrax) juveniles fed with a diet containing fluorescent MP particles (1-5 mu m) for 16 weeks. Results indicate MP translocation to fillet, with mean fillet MP content calculated as 0.36 +/- 0.29 MP/g(-1) fillet on the basis of manual fluorescent microscopy counts and 0.15 +/- 0.28 MP/g(-1) fillet on the basis of automated fluorescent microscopy counts. The retention/translocation rate is estimated at approximately 1 MP reaching the fillet for every 1.87 x 10(7) ingested in the experimental diet. This study presents first data of MP translocation from feed to the tissue fillet in European seabass and aids future examinations of the MP load in seafood for human consumption.