The Influence of an Ozone,Chlorine and Chlorine Dioxide Treatment on Mutagentic Activity in (Drinking) Water

Three disinfectants, viz. chlorine, chlorine dioxide, and ozone, were compared with respect to the formation of organic mutagens and halogenated organic compounds in drinking water. Chlorine increased the mutagenic activity (Ames test) drastically, as well as the level of halogenated organics. High chlorine dioxide doses (5 – 15 mg/L C10₂) also showed a drastic increase of mutagenic activity, while relatively low doses of chlorine dioxide (< 5 mg/L CIO₂) in most cases showed no effect or a slight increase in mutagenic activity. Hardly any increase in the level of halogenated organics was observed after this treatment.