1、外文资料the United NationsInternational Drinking Water Supply and Sanitation Decade(19811990) failed to achieve its goal of universal access to safe drinking water and sanitation by 1990 (World Health Organization WHO, 2003). Even though service levels rose by more than 10 percent during the decade, 1.1
2、 billion people still lacked access to improved water supplies, and 2.4 billion people were without adequate sanitation, in 1990 (WHO/UNICEF, 2000). Reasons cited for the decades failure include population growth, funding limitations, inadequate operation and maintenance, and continuation of a tradi
3、tional “business as usual” approach (WHO/UNICEF, 1992).The world is on schedule to meet the Millennium Development Goal (MDG), adopted by the UN General Assembly in 2000 and revised after the World Summit on Sustainable Development in Johannesburg, to “halve, by 2015, the proportion of people withou
4、t sustainable access to safe drinking water and basic sanitation” (World Bank Group, 2004; WHO/ UNICEF, 2004). However, success still leaves more than 600 million people without access to safe water in 2015 (WHO/ UNICEF, 2000).In addition, although the MDG target specifically states the provision of
5、 “safe” drinking water, the metric used to assess the MDG target is the provision of water from “improved” sources, such as boreholes or household connections, as it is difficult to assess whether water is safe at the household level (WHO/UNICEF, 2004). Thus, many more people than estimated may drin
6、k unsafe water from improved sources.HOUSEHOLD WATER TREATMENT AND SAFE STORAGETo overcome the difficulties in providing safe water and sanitation to those who lack it, we need to move away from “business as usual” and research novel interventions and effective implementation strategies that can inc
7、rease the adoption of technologies and improve prospects for sustainability. Despite general support for water supply and sanitation, the most appropriate and effective interventions in developing countries are subject to significant debate. The weak links among the water, health, and financial sect
8、ors could be improved by communication programs emphasizing health1as well as micro- and macroeconomicbenefits that could be gained. The new focus on novel interventions has led researchers to re-evaluate the dominant paradigm that has guided water and sanitation activities since the 1980s. A litera
9、ture review of 144 studies by Esrey et al. (1991) represents the old paradigm, concluding that sanitation and hygiene education yield greater reductions in diarrheal disease (36 percent and 33 percent, respectively) than water supply or water quality interventions.2 However, a more recent meta-analy
10、sis commissioned by the World Bank contradicted these findings, showing that hygiene education and water quality improvements are more effective at reducing the incidence of diarrheal disease (42 percent and 39 percent, respectively) than sanitation provision and water supply (24 percent and 23 perc
11、ent, respectively) (Fewtrell & Colford, 2004).The discrepancy between these findings can be attributed in part to a difference in intervention methodology. Esrey et al. (1991) reviewed studies that largely measured the impact of water quality improvements at the source (i.e., the wellhead or communi
12、ty tap). Since 1996, a large body of published work has examined the health impact of interventions that improve water quality at thepoint of use through household water treatment and safe storage (HWTS; Fewtrell & Colford, 2004). These recent studiesmany of them randomizedcontrolled intervention tr
13、ialshave highlighted the role of drinking water contamination during collection, transport, and storage (Clasen & Bastable, 2003), and the health value of effective HWTS (Clasen et al., 2004; Quick et al.,1999, 2002; Conroy et al., 1999, 2001; Reller etal., 2003). In 2003, as the evidence for the he
14、alth benefits of HWTS methods grew, institutions from academia, government, NGOs, and the private sector formed the International Network to Promote Household Water Treatment and Safe Storage,housed at the World Health Organization in Geneva, Switzerland. Its stated goal is “to contribute to a signi
15、ficant reduction in waterborne disease, especially among vulnerable populations, by promoting household water treatment and safe storage as a key component of water, sanitation, and hygiene programmes” (WHO, 2005). HWTS OPTIONS This article summarizes five of the most common HWTS optionschlorination
16、, filtration (biosand and ceramic), solar disinfection, combined filtration/ chlorination,and combined flocculation/chlorinationand describes implementation strategies for each option.3 We identify implementing organizations and the successes, challenges, and obstacles they have encountered in their projects. We consider sources of funding and the potential to distribute and sustain each option on a large scale, and propose goals for future research and implementati
