Waster Pasteurization through Improved Cookstoves (WAPIC)

Two of the main causes of morbidity and mortality, particularly among children under five, in developing countries like Nepal are diarrhea and Acute Respiratory Infections (ARI). Household environmental factors are known to be the major causes for both these health outcomes. In fact poor water and sanitation and indoor air pollution are the two largest environmental risk factors. Safe water and effective sanitation can significantly reduce diarrhoeal diseases while improved indoor air quality (IAQ) can significantly reduce the chances for ARI, particularly among children. Two simple, cost effective and well proven interventions implemented at the household level – point-of-use water treatment to provide safe water and improved cook stoves to reduce indoor air pollution – offer the potential to tackle these two major killers and make substantial gains toward the achievement of Millennium Development Goals 1 (eradicate poverty), 4 (reduce child mortality), 5 (improve maternal health) and 7 (environmental sustainability). Simple household water treatment (HWT) options, such as boiling, filtration, solar water disinfection and chlorination, provide a means by which poor people without access to improved water supplies can take charge of their own water security, while improved cook stoves (ICS) can reduce indoor air pollution by about 70 percent. In Nepal, significant efforts are being made by the government as well as non-government organizations to promote HWT as well as ICS. However, there is clearly a need to do a lot more so as to rapidly scale up these efforts. Furthermore, there is also a need to coordinate efforts among promoters of HWT and promoters of IAQ so as to optimize the outcomes and capitalize on potential areas for synergy. The motivation for integrating the two household environmental health interventions through a combined intervention so as to achieve more per unit of input than two interventions run separately, has led ENPHO to design Water Pasteurization thorugh Improved Cookstoves (WAPIC). Both water pasteurization and improved cook stoves are commonly used technologies. Pasteurization is a common practice in the food industry and a few attempts have been done to pasteurize water by exposing water to sunlight or heat from stoves. In Bangladesh, Islam and Johnston (2006) have developed and tried the “chuli” system where a hollow aluminum coil is built into the clay stove and water is passed through the coil at a flow rate of 500 mL per minute during cooking times. By maintaining the water temperature at around 70°C, they were able to completely inactivate thermotolerant coliforms in the water. The technology was initially tried in the laboratory and later in 2004/05 more than 500 chulis were installed in six villages and monitored over a period of several months. WAPIC is a modified version of the chuli with the pasteurization tube being attached to a two pot-hole mud brick ICS, which is the most commonly used ICS in Nepal. The waste heat in the chimney of the stove is used to pasterize drinking water which is passed thorugh a small tube wrapped around the chimney.