Removal of enteric viruses and Escherichia coli from municipal treated effluent by zebra mussels

Dreissena polymorpha is awidespread ?lter-feeder species, resistant to a broad range of environmental conditions and different types of pollutants,which has recently colonized Italian freshwaters. Althoughwidely used tomonitor pollution in freshwater environments, this species is also an important food source for some ?sh and water birds. It can also be used to concentrate or remove particulate organicmatter to interrupt avian-to-human transmission of pollutants and control health risks for animals and humans. In this study, the accumulation/inactivation in D. polymorpha of human health-related spiked enteric viruses was described. The removal of endogenous Escherichia coli, the classical indicator of fecal contamination,was tested aswell.Our preliminary lab-scale results demonstrate that zebra mussels can reduce signi?cantly poliovirus titer after 24 h and rotavirus titer after 8 h. E. coli countswere also reduced in the presence of zebramussels by about 1.5 log after 4 h and nearly completely after 24 h. The fate of the two enteric viruses after concentration by zebra mussels was also investigated after mechanical disruption of the tissues. To our knowledge, the accumulation fromwater and inactivation of human health-related enteric viruses by zebra mussels has never been reported.