Ozone is used in many municipal water supplies. The United States Food and Drug Administration has asked all bottled water companies to ozonate their water in order to prevent disease. According to Newsweek,”Chlorination, used in most every municipal system, kills or inactivates viruses as well as bacteria like E. coli and salmonella. It does not kill anthrax spores. Some plants also treat water with ozone, which is more effective in killing protozoans like crypto.”