Article pubs.acs.org/est
Effectiveness of Chlorine Dispensers in Emergencies: Case Study Results from Haiti, Sierra Leone, Democratic Republic of Congo, and Senegal Travis M. Yates,†,‡ Elise Armitage,† Lilian V. Lehmann,† Ariel J. Branz,‡ and Daniele S. Lantagne*,†,‡,§ †
Innovations for Poverty Action, New Haven, Connecticut 06510, United States Department of Civil and Environmental Engineering, Tufts University, Medford, Massachusetts 02155, United States § Sustainability Science Program, Center for International Development, Harvard University, Cambridge, Massachusetts 02138, United States ‡
ABSTRACT: Dispensers are a source-based water quality intervention with promising uptake results in development contexts. Dispenser programs include a tank of chlorine with a dosing valve that is installed next to a water source, a local Promoter who conducts community education and refills the Dispenser, and chlorine refills. In collaboration with response organizations, we assessed the effectiveness of Dispensers in four emergency situations. In the three initial and four sustained response phase evaluations, 70 Dispenser sites were visited, 2057 household surveys were conducted, and 1676 water samples were analyzed. Across the evaluations, reported Dispenser use ranged from 9 to 97%, confirmed Dispenser use (as measured by free chlorine residual) ranged from 5 to 87%, and effective use (as measured by improvement in household water quality to meet international standards) ranged from 0 to 81%. More effective Dispenser interventions installed Dispensers at point-sources, maintained a high-quality chlorine solution manufacturing and distribution chain, maintained Dispenser hardware, integrated Dispensers projects within larger water programs, remunerated Promoters, had experienced project staff, worked with local partners to implement the project, conducted ongoing monitoring, and had a project sustainability plan. Our results indicate that Dispensers can be, but are not always, an appropriate strategy to reduce the risk of waterborne diseases in emergencies.
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INTRODUCTION An estimated 748 million people lack access to improved water supplies,1 and an estimated 1.2 billion more consume drinking water from improved sources with an elevated risk of contamination at the source, or during collection, transport, or storage.2 Unsafe drinking water is estimated to cause 502 000 deaths from diarrhea annually, mainly among young children.3 The addition of chlorine to stored household drinking water has been shown to improve the microbiological quality of water and reduce the burden of diarrheal disease in users.4,5 While there is active debate about the magnitude of this effect,6 chlorine inactivates most diarrhea-causing bacteria and viruses,7 provides residual protection in stored household water, and effectively reduces disease in contexts where drinking water is a pathogen transmission route.8 However, outside some exemplary programs,8,9 adoption of chlorine-based household water treatment (HWT) products have been low.10 In 2006, researchers from Harvard University and the University of California Berkeley found that a spring protection intervention was less efficacious at reducing diarrheal disease than anticipated, because spring water was recontaminated during water collection and storage in the home.11 To address this, the researchers worked in collaboration with Innovations for Poverty Action (IPA) to develop the Chlorine Dispenser System (Dispensers). A Dispensers program includes three elements: © 2015 American Chemical Society
(1) hardware installed next to a water source that dispenses chlorine solution, (2) a local Promoter who refills the Dispenser and conducts community education, and (3) a supply chain of chlorine refills. When Dispensers were installed at no cost at the water source, 50−61% of households with stored water who used the Dispenser source had total chlorine residual (TCR) in household water up to 2.5 years after Dispenser installation.12 This is compared to 6−14% TCR in control households who purchased chlorine bottles from local vendors. Based on these adoption numbers, Dispenser programs have been scaled-up in east Africa, with 6050 Dispensers installed at the end of 2013 (average 43% adoption rate),13 and >10 000 total Dispensers installed as of end-2014.14 With this documented success in the development context, there was interest in whether Dispenser interventions would be appropriate in emergency response. Drinking water is an immediate priority in most emergency situations, including natural disasters, complex political emergencies, and outbreaks.15 When normal water supplies are interrupted or compromised Received: Revised: Accepted: Published: 5115
January 19, 2015 March 3, 2015 March 12, 2015 March 12, 2015 DOI: 10.1021/acs.est.5b00309 Environ. Sci. Technol. 2015, 49, 5115−5122
Article
Environmental Science & Technology
household was also collected. Samples were stored on ice at
