Virucidal and bactericidal effects of electrolyzed oxidizing water: Comparison of disinfectant effect with electrolyzed oxidizing water and hypochlorous acid

Electrolyzed oxidizing (EO) water, synthesized by electrolysis of tap water and sodium chloride (0.05%) with a diaphragm between the cathode and anode, and collected from the anode side, exhibited strong virucidal and bactericidal activity. The oxidation-reduction potential (ORP) of EO water in a ph of 2.70 or less was 1, 100mV or more. When sodium hypochlorite was mixed with hydrochloric acid, hydrochlorous acid was synthesized (NaClO+HCl→HClO+NaCl) resulting in an ORP of 1, 100 mV or more at low pH. The minimum microbicidal concentration (MMC) of chlorine (Cl)(mg/l) showing virucidal and bacter-icidal effects in EO water was compared with that of the synthesized hypochlorous acid using herpes simplex virus type 1, polio virus and Enterococcus faecalis. The MMC of Cl in EO water was less than that in the hypochlorous acid. The results indicate that the virucidal and bactericidal effects of EO water differ from those of hypochlorous acid only because substances contained in EO water, such as Cl-, ClO2, H2O2, OH+ (hydroxyl radical) etc., seem to synergistically support such activity by balancing in a competitive state in acidic conditions.