Ocean acidification increases the accumulation of titanium dioxide nanoparticles (nTiO2) in edible bivalve mollusks and poses a potential threat to seafood safety

摘要

Large amounts of anthropogenic CO2 in the atmosphere are taken up by the ocean, which leadsto ‘ocean acidifcation’ (OA). In addition, the increasing application of nanoparticles inevitablyleads to their increased release into the aquatic environment. However, the impact of OA on thebioaccumulation of nanoparticles in marine organisms still remains unknown. This study investigatedthe efects of OA on the bioaccumulation of a model nanoparticle, titanium dioxide nanoparticles(nTiO2), in three edible bivalves. All species tested accumulated signifcantly greater amount of nTiO2in pCO2-acidifed seawater. Furthermore, the potential health threats of realistic nTiO2 quantitiesaccumulated in bivalves under future OA scenarios were evaluated with a mouse assay, which revealedevident organ edema and alterations in hematologic indices and blood chemistry values under futureOA scenario (pH at 7.4). Overall, this study suggests that OA would enhance the accumulation of nTiO2in edible bivalves and may therefore increase the health risk for seafood consumers.