title: Emergency water treatment with bleach in the United States: the need to revise EPA recommendations.
abstract: During emergencies in the United States, the Environmental Protection Agency (EPA) currently recommends using bottled water, or boiling or treating water by adding 1/8 teaspoon (or 8 drops) of bleach to 1 gal of water. This bleach recommendation is internally inconsistent, a relatively high chlorine dose (5.55-8.67 mg/L), and unsupported by evidence. In this study, bleach was added in three different dosages to six waters available to emergency-affected populations in each of six states; free chlorine residual (FCR) and Escherichia coli/total coliforms were measured 1-24 h after treatment. Data were analyzed using four efficacy criteria. Results indicated the dosages in the current EPA recommendation are unnecessarily high to ensure (1) maintenance of FCR for 24 h after treatment, (2) absence of E. coli/total coliforms, and (3) establishment of a CT-factor sufficient to inactivate Giardia lamblia and enteric viruses 1 h after treatment. Additionally, emergency-prone populations did not have the materials to complete treatment with bleach in their household. Therefore, we recommend EPA review and revise the current recommendation to establish an internally consistent, criteria-based recommendation that is usable by emergency-affected populations. We also recommend investigating the use of new or commercially available water treatment products for emergency response in the United States.
authors.affiliation: Waterborne Diseases Prevention Branch, Centers for Disease Control and Prevention , Atlanta, Georgia 30333, United States.
authors.forename: Daniele
authors.initials: D
authors.lastname: Lantagne
authors.forename: Bobbie
authors.initials: B
authors.lastname: Person
authors.forename: Natalie
authors.initials: N
authors.lastname: Smith
authors.forename: Ally
authors.initials: A
authors.lastname: Mayer
authors.forename: Kelsey
authors.initials: K
authors.lastname: Preston
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Blanton
authors.forename: Kristen
authors.initials: K
authors.lastname: Jellison
mesh_terms: D057886:Bleaching Agents / Q000737:chemistry*; D004630:Emergencies; D004755:Enterobacteriaceae / Q000187:drug effects; D004770:Enterovirus / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D016829:Giardia lamblia / Q000187:drug effects; D006801:Humans; D012973:Sodium Hypochlorite / Q000737:chemistry* / Q000494:pharmacology; D014481:United States; D014484:United States Environmental Protection Agency; D014871:Water Microbiology; D018508:Water Purification / Q000379:methods*; D060753:Water Quality
chemical_list: D057886:Bleaching Agents; D012973:Sodium Hypochlorite