Toxicokinetics and tissue distribution of cadmium-based Quantum Dots in the marine mussel Mytilus galloprovincialis

Environmental health hazards of Quantum Dots (QDs) are of emergent concern, but limited data is available about their toxicokinetics (TK) and tissue distribution in marine bivalves. This study investigated the QDs behavior in seawater, their TK and tissue distribution in Mytilus galloprovincialis, in comparison with soluble Cd. Mussels were exposed to CdTe QDs and soluble Cd for 21 days at 10 μgCd L−1 followed by a 50 days depuration. TK of QDs in mussels is related to the homo-aggregate uptake, surface charge, aggregation and precipitation as key factors. There were tissue- and time-dependent differences in the TK of both Cd forms, and soluble Cd is the most bioavailable form. Digestive gland is a preferential site for QDs storage and both Cd forms are not eliminated by mussels (t1/2>50 days). Results indicate that the TK model of CdTe QDs in marine mussels is distinct from their soluble counterparts. [Display omitted] •Toxicokinetics of CdTe QDs and soluble Cd in mussels are mediated by different mechanisms.•Digestive gland is a preferential site for both Cd forms storage.•CdTe QDs and soluble Cd are not eliminated by mussels (t1/2 > 50 days).•Toxicokinetics models were compared between CdTe QDs and soluble Cd in marine mussels. Toxicokinetic model of CdTe QDs in the marine mussel Mytilus galloprovincialis is distinct from their soluble counterparts.