Behavioral adaptation to improved environmental quality

Access to safe drinking water, sanitation, and hygiene (WASH) in developing countries is recognized as critical for global public health. In 2015, it was estimated that 2.3 billion people lacked access to basic sanitation facilities, with millions of people dying each year due to fecal-borne diseases (most commonly diarrhea) as a result of inadequate WASH (WHOand UNICEF, 2019). The WASH research literature to date has largely focused on the effectiveness of various interventions in increasing sanitation coverage and on the associated health improvements (Clasen et al., 2014; Patil et al., 2014; Briceno et al., 2017; Null et al., 2018; Luby et al., 2018; Augsburg and Rodriguez-Lesmes, 2018; Pickering et al., 2019; Cameron et al., 2019, 2021, 2022), with a smaller, but growing, number of studies examining other outcomes, such as education and cognitive development (Adukia, 2017; Coswosk et al., 2019; Orgill-Meyer and Pattanayak, 2020; Spears and Lamba, 2016; Zhang and Xu, 2016), and labor supply, reflecting a decrease in the domestic cleaning burden (Wang and Shen, 2022). With few exceptions, these studies focus on the impact of own toilet construction on household outcomes. Improved sanitation however can also generate externalities to surrounding households through a cleaner and healthier local environment. Three recent studies suggest that such externalities matter. Cameron et al. (2022), using data from randomized trials in India, Indonesia, Mali and Tanzania, find that child height increases once village sanitation coverage exceeds 50%; and Cameron et al. (2021) show, using the same data as this study, that improvements in children’s height-for-age z-score (HAZ) mostly reflect the degree of adoption of improved sanitation at the local (village) level, rather than their household’s decision alone. In a similar vein, Motohashi (2022) analysis of a sanitation policy in India that incentivized the construction of over 100 million latrines, finds that its effect in terms of reduced diarrheal mortality is much weaker in areas with poor fecal sludge treatment, because the newly built latrines contribute to river pollution, which affects the whole community.

source :

https://www.adb.org/publications/behavioral-adaptation-improved-environmental-quality