Perceptions of safety and household behaviors to improve drinking water quality in peri-urban Cambodia

Abstract

How do perceptions of water quality affect household water-related hygiene and behavior, and can these perceptions be changed by the provision of household-specific water quality information?

Despite some recent progress, diarrheal disease continues to be a significant cause of illness and death, particularly among children under five years of age (UNICEF 2012; Liu et al. 2012; Jeuland et al. 2013). It has been argued that close to 90% of the deaths due to diarrhea are preventable and caused by a combination of poor water, hygiene, and sanitation (Prüss-Üstün and Corvalán 2006). The location of this particular study, Cambodia, is one example of a country where trends in coverage and diarrhea disease are favorable, but where challenges persist (WHO 2004; DHS 2010).

A wide variety of factors are thought to have contributed to the recent global progress in reducing diarrheal disease, including the expansion of access to improved and piped water and sanitation services (Fink et al. 2011; Jeuland et al. 2013) and low-cost household- and community-level water and sanitation interventions, including hand-washing and hygiene education campaigns, programs to encourage use of latrines rather than open defecation, and the spread of low-cost point-of-use (POU) water treatment products (Waddington et al. 2009). Yet despite increased promotion of low-cost methods for decreasing the risks of diarrhea, demand for and utilization of many such technologies and behavioral changes remains surprisingly modest (Figueroa and Kincaid 2007; Zwane and Kremer 2007; Luby et al. 2008; Pattanayak and Pfaff 2009; Whittington et al. 2012).

Several recent studies have considered whether the provision of specific information about a household’s own water quality (rather than general information about health and disease prevention) can influence the demand for higher quality water and health-related behaviors more generally (Hamoudi et al. 2012; Jalan et al. 2008; Madajewicz et al. 2007, Luoto 2009). Collectively, these studies provide some evidence that household behaviors are responsive to such information (Lucas et al. 2011). Still, additional research is needed to better understand the precise mechanisms underlying the impacts of such information.

This study aims to contribute to knowledge about the demand for POU treatment in two ways. First, we implement a randomized information intervention combined with elicitation of subjective perceptions of water quality to investigate whether and how the supply of household-specific information affects household perceptions about the safety of their own drinking water. Second, we consider the effect of household perceptions of drinking water safety on a set of behaviors – either through increased purchase and use of a chlorine-based product called Aquatabs that was sold directly to households, or through changes in other preventive water-related behaviors. A random (exogenous) information treatment is required to isolate the effect of perceptions on behavior because perceptions and drinking-water behaviors are likely related to many of the same unobservable factors.

A major challenge facing studies of the link between perceptions of drinking water safety and the demand for improved water quality is that many of the same factors influence both perceptions of water quality and households’ water and sanitation preferences, and not all of those factors are observable. Our identification strategy for isolating the effects of perceptions on demand therefore hinges on the provision of an exogenous “shock” to household perceptions of water safety. This shock is implemented via the exogenous (randomized) delivery of household-specific water quality information to a sub-sample of survey households.

To better assess the degree to which perceptions of water safety drive demand for such preventive behaviors, we use a two-stage least-squares model. The first stage equation allows a test of the hypothesis that the supply of household-specific water quality information shifts perceptions of water safety, while the second looks at how changes in perceptions relate to the household behaviors of interest.

Though the study was originally conceived to test the demand for Aquatabs, a chlorine-based disinfectant, we do consider outcome variables that correspond to a much wider set of preventive water-related behaviors. Specifically, we assess the degree to which households shift their water sourcing, handling and storage of drinking water, as well as overall water treatment, as a result of the information and/or their perceptions of water safety.

Data for this project comes from three waves of panel data from 915 households in peri-urban Cambodia. The first wave was conducted in 2011 while the second and third took place in 2012. During the second visit, all households had their drinking water tested for e.coli contamination. A randomly selected half of the households were given the results of this water test before being asked about their perceptions of the safety of their water. All households were given the opportunity to purchase a chlorine-based water treatment product called Aquatabs. Six weeks later, in the third visit, all households were revisited. In this final survey, many of the same questions were asked once more, in addition to questions about whether they used their chlorine tablets and if they changed any of their water-related behaviors.

We first assessed the effect of water quality information on perceptions of water safety, finding that evidence of contamination significantly decreased perceptions of water safety, whereas the opposite result tended to increase these perceptions, at least among literate households. Still, the explanatory power of the model estimating perceptions was relatively modest.

We then used the exogenous information shock as an instrument for estimating the influence of such perceptions on demand for a chlorine-based water treatment product and a variety of other water-related preventive behaviors. We found that households with better perceptions of the safety of their water bought fewer Aquatabs and were less likely to engage in behaviors to make their water safe, such as overall water treatment or collection of water from higher quality sources. On the other hand, households with worse perceptions of their water safety were more likely to engage in a variety of these behaviors.

Taken together, these results suggest that perceptions play an important role in the demand for water treatment products and in the willingness of households to engage in time-consuming and costly behaviors to ensure that their water is safe. These results lend additional credibility to previous findings in the literature that giving households tailored and salient information on water quality does affect short-term preventive behaviors that have been shown to deliver health benefits (Jalan and Somanathan 2008; Hamoudi et al. 2012).