Hypochlorite Solution Expiration and Stability in Household Water Treatment in Developing Countries

• Published in: Journal of environmental engineering (New York, N.Y.) N.Y.), 2011-02, Vol.137 (2), p.131-136
• Main Authors: Lantagne, D, Preston, K, Blanton, E, Kotlarz, N, Gezagehn, H, van Dusen, E, Berens, J, Jellison, K
• Format: Article
• Language: English
• Subjects: Applied sciences; Bottles; Developing countries; Exact sciences and technology; Expiration; Households; Microorganisms; Pollution; Stability; TECHNICAL PAPERS; Water treatment
• ISSN: 0733-9372; 1943-7870
• DOI: 10.1061/(ASCE)EE.1943-7870.0000299

Household water treatment with dilute hypochlorite solution has been shown to improve microbiological water quality and reduce diarrheal disease in developing countries. One concern raised by governmental agencies, implementers, and nongovernmental organizations is whether the hypochlorite solution remains stable during distribution and after the bottle is opened and usage begins. In this study, laboratory and field research was conducted to determine the expiration date and stability in the home of hypochlorite solution. Expiration-date testing found that pH-stabilized ∼1.25% hypochlorite solution made using various production techniques in Ethiopia, Guinea, and Nigeria was stable for a minimum of 12 months in temperatures less than 35°C . Stability testing during laboratory simulated normal usage showed no degradation, and 77–91% of bottles collected from households tested met standards. Hypochlorite solution concentration drops rapidly when pH is not stabilized, when pH levels fall, and when solution is exposed to direct sunlight.