RESUMO
Marine bivalves are known to ingest microplastics, but information on the consequences for their physiological performance is limited. To investigate a potential exposure pathway that has not yet been addressed, we mimicked the resuspension of microplastics from the sediment in a laboratory exposure experiment. For this, we exposed the Asian green mussel Perna viridis to 4 concentrations (0mg/l, 21.6mg/l, 216mg/l, 2160mg/l) of suspended polyvinylchloride (PVC) particles (1-50µm) for two 2-hour-time-periods per day. After 44days, mussel filtration and respiration rates as well as byssus production were found to be a negative function of particle concentration. Furthermore, within 91days of exposure, mussel survival declined with increasing PVC abundance. These negative effects presumably go back to prolonged periods of valve closure as a reaction to particle presence. We suggest that microplastics constitute a new seston component that exerts a stress comparable to natural suspended solids.