Assessing the Disinfecting Power of Chlorite in Drinking Water

Abstract

Abstract The goal of this study was to review and confirm experimentally chlorite effectiveness as a drinking water disinfectant. The steps in the experiment were a series of laboratory assays performed on three types of microorganisms, Bacillus subtilis spores, MS2 coliphages, as well as heterotrophic (HPC) bacteria, to verify chlorite action in water. The tests showed that chlorites have no disinfectant effect on B. subtilis spores (CT > 106 mg min/L), that they slightly decrease HPC bacterial regrowth and, finally, that a dose of 1 and 10 mg ClO2-/L can inactivate almost 2 log and 4.5 log of MS2 phages, respectively, after 9 days of contact time. It would therefore appear that chlorites are not a good primary disinfectant, but do exhibit a bacteriostatic effect.