Modelling and Guidance for the Distribution of Chlorine-Based Disinfectants for Household Water Treatment in Emergency Settings.
Mitro, Brittany R.
- Chlorine-based disinfectants are one of the most commonly used forms of household water treatment for emergency interventions. A unique property of these disinfectants is the maintenance of residual chlorine post-distribution, allowing for the continued disinfection of water sources. The efficacy of an intervention using chlorine-based disinfectants is reliant on this residual maintenance. However... read more, while the biocidal properties are well-studied, the residual decay pathways of different disinfectants are still widely unknown. Four most commonly used disinfectants were studied with regard to the potential decay pathways, including hypochlorite salts, sodium dichloroisocyanurate (NaDCC), chlorine dioxide, and chloramines. The available models for chlorine decay were studied and analyzed for applicability to each compound based on the available information on chemical reaction pathways and physical properties.The effectiveness of an intervention, however, is not based solely on the efficacy of a given product. Therefore, one increasingly used product, Aquatabs, was studied through key informant interviews to create an evidence-based set of recommendations from experience in the field. Aquatabs are a form of NaDCC manufactured by Medentech® and are available as tablets of 10 different dosages for 5 quantities of water, with one set of 5 dosages for development or long-term usage and another set of 5 dosages for emergencies. This has been reported to cause confusion among beneficiaries, and was the focus of the semi-structured interviews. The information was synthesized to create recommendations for future use of Aquatabs and chlorine-based disinfectants in general. Together with information about the residual maintenance, the recommendations made provide a holistic view of chlorine-based disinfectant use in emergency settings and the solutions possible to several issues that are known about household water treatment generally.read less