A visible light driven photoelectrocatalytic fuel cell (PECFC) recently developed at Aberdeen has been shown to have the capacity to oxidatively degrade a wide range of contaminants commonly found in water supplies and associated with risk to human health. It has also shown great potential to kill human pathogens such as toxigenic strains of Escherichia coli. Remediation of chemical contaminants has been confirmed by analytical chemistry, and we have integrated a biosensor based assay into the process to confirm concomitant removal of all chemical toxicity. We have also used a biosensor approach to confirm considerable reduction in infection potential associated with human pathogens. The PECFC used to generate the data comprised a basic, batch system with sub-optimal catalyst and static conditions. We are now evaluating the performance of a dynamic, flow reactor (with catalyst optimisation) which continually delivers water borne contaminants (molecules or cells) to the catalyst surface.