(514l) Pulsed Electric Field (PEF) Device: Design, Performance and Deployment in an Elderly Home for Tap Water Disinfection

The most common way of municipal water disinfection, i.e., chlorination, is now deemed inadequate given the emergence and spread of antibiotic-resistant bacteria. Reports about chlorine-induced antibiotic resistance and how chlorination increases the concentrations of antibiotic resistance genes in water, show the critical need for more innovative disinfection systems. This work addresses this concern through the development of a water disinfection device that utilizes pulsed electric field (PEF) to initiate cell permeability and irreversible electroporation on bacterium cell membrane that leads to cell death. The disinfection mechanism does not induce adaptation effects as it preserves the cell’s nuclease activity or the provision of enzymes that will degrade the DNA. It then prevents the spread of resistance plasmids from antibiotic-resistant bacteria. The PEF device is composed of micro-engineered electrodes and a low voltage circuit which can either be battery-operated or plugged to a socket. Laboratory studies show that the PEF device can deliver as high as 2 log reduction against common gram-negative bacteria found in water (i.e. Escherichia Coli K12) in less than 1 minute of treatment. Prototypes were installed in the pantry faucets of a local elderly home. Field test results show that the bacteria present in the untreated tap water are mostly gram-negative non-lactose fermenting bacteria and that the current prototype can significantly decrease the tap water’s bacterial concentration.