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Need to revise recommendations for emergency water treatment with bleach in the United States

Need to revise recommendations for emergency water treatment with bleach in the United States. Daniele Lantagne, Bobbie Person, Natalie Smith, Ally Mayer, Kelsey Preston, Elizabeth Blanton, Kristen Jellison Centers for Disease Control and Prevention & Lehigh University.

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Need to revise recommendations for emergency water treatment with bleach in the United States

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  1. Need to revise recommendations for emergency water treatment with bleach in the United States Daniele Lantagne, Bobbie Person, Natalie Smith, Ally Mayer, Kelsey Preston, Elizabeth Blanton, Kristen Jellison Centers for Disease Control and Prevention & Lehigh University

  2. The 3 B’s: Bottled, boil, bleach If you can't boil water, you can disinfect it using household bleach. Bleach will kill some, but not all, types of disease-causing organisms that may be in the water. If the water is cloudy, filter it through clean cloths or allow it to settle, and draw off the clear water for disinfection. Add 1/8 teaspoon (or 8 drops) of regular, unscented, liquid household bleach for each gallon of water, stir it well and let it stand for 30 minutes before you use it. Store disinfected water in clean containers with covers. Additionally, in the more information section, the instructions read “double the amount of chlorine for cloudy, murky or colored water or water that is extremely cold.” Current EPA Emergency Guidelines

  3. Inconsistent dosing: 1/8 teaspoon != 8 drops High dosage: 1/8 teaspoon (5.25% bleach in 1 gallon): 8.67 mg/L 8 drops (5.25% bleach, 1 gallon, 15-25 drops/mL):4.44 - 5.55 mg/L EPA maximum: 4 mg/L WHO maximum: 5 mg/L Used in HWTS in developing countries: 2 mg/L Double these doses for turbid water Concerns with guidelines - technical

  4. How the recommendations propagate Whether the items necessary to complete the recommended treatment method are available Whether people feel confident in completing this water treatment method 1/196 in Hurricane Rita knew correct dose (Ram) Concerns with guidelines - social

  5. Propagation of recommendations

  6. Addressed this in working group Result: Need data from US Quantitative 6 states: Colorado, Georgia, Minnesota, Penn, Texas, Wash 6 waters: tap, water heater, surface (filtered & not), wells Dosage testing at 3 doses, including microbiology and CT-factor Qualitative 3 states: Louisiana, Florida, Georgia Stakeholder interviews Household visits to 9 families with four directions Observe and test ability to make solution Methods

  7. 6 tap water, 6 water heater, 11 wells, 1 rain barrel 6 surface water (raw, filtration through linen napkin) pH: mean 7.85 (range: 6.5-9.4) 7/36 exceeded 8.0 Turbidity: mean 3.89 NTU (range: 0-23.2) 18/36 (50%) >1.0 NTU; 4/36 (11%) between 10-100 NTU Temperature varied geographically and seasonally E. coli only in surface water (<10–180 CFU/100 mL) Total Coliforms found in 18/36 samples Quantitative results - water quality (36)

  8. Three criteria FCR >= 0.2 mg/L and <= 4.0 mg/L E. coli and Total Coliform = 0 CFU/100 mL Meeting 3-log reduction for Giardia Quantitative results - Dosage

  9. What criteria are most relevant? FCR maintenance / FCR guidelines the inactivation of Giardia in surface waters the absence of E. coli / Total Coliform a CT-factor to remove the majority of bacteria and viruses that cause diarrheal disease a combination of the above? In any case, current dosages are too high Quantitative results - Standard?

  10. The government should, and does, provide bottled water A minority knew about bleach for treatment None knew dosage All reported serious concerns (Poison Control Center) Stated instructions are too confusing “Bleach will kill some, but not all, types of disease-causing organisms.” “Draw off” Prefer kit Laminated instruction, container, pre-measured dose Qualitative results - Stakeholder meetings (86)

  11. Presence of materials 6/9 had bleach in home None was unscented, non-expired, near 5.25% 1/9 families had a 1/8 teaspoon 2/9 had dropper 4/9 had a gallon container Methods Existing (1/8 tsp), existing (8 drops), other dropper, stock solution (WHO) Dropper method easiest, most accurate, and preferred Improve by having 2-L container, pictoral directions Qualitative results - Household interviews

  12. Based on these results, both quantitative and qualitative, it is recommended that the current recommendations for emergency water treatment with household bleach be reviewed to establish an internally consistent, scientifically verified dosage regime that balances existing regulatory criteria, recommended water sources, population exposure to pathogens of concern, and availability of items (bleach, droppers, measurers, containers) necessary to treat water in the home, including the potential for development of a commercial product for water treatment instead of recommending the use of household bleach. Summary

  13. The stakeholders interviewed The households who completed the qualitative testing The households who hosted the testing Happy to take questions: daniele.lantagne@tufts.edu Acknowledgements

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