Low-cost, local production of a safe and effective disinfectant for resource-constrained communities

Improved sanitation and hygiene depend on the accessibility and availability of effective disinfectant solutions. These disinfectant solutions are unavailable to many communities worldwide due to resource limitations, among other constraints. Safe and effective chlorine- based disinfectants can be produced via simple electrolysis of salt water, providing a low-cost and reliable option for on-site, local production of disinfectant solutions to improve sanitation and hygiene. We report on a system (herein called “Electro-Clean”) that can produce concentrated solutions of hypochlorous acid (HOCl) using only low-cost and now widely accessible materials. Using only table salt, water, graphite welding rods, and a DC power supply, HOCl solutions (∼1.5 liters) of 0.1% free chlorine (i.e. 1000 ppm) can be safely produced in less than two hours at low potential (5 V DC) and modest current (∼5 A). Rigorous testing of free chlorine production and durability of the Electro-Clean system components, described here, have been verified to work in multiple locations around the world by our project team, including microbiological tests conducted in two different countries to confirm the biocidal efficacy of the Electro-Clean solution as a surface disinfectant. We provide cost estimates for making HOCl locally with this method in the USA, India, and Mexico. Our findings show that Electro-Clean is an affordable alternative to off-the-shelf commercial chlorinator systems in terms of first costs (or capital costs), and cost-competitive relative to the unit cost of the disinfectant produced. By minimizing dependence on supply chains and allowing for local production, the Electro-Clean production process has the potential for improving public health by addressing the need for high- strength disinfectant solutions in resource-constrained communities. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement There was partial financial support for this work from the Balaton Group, and Rudd Chair funds from Professor Ashok Gadgil. The Higher Technological Institutes of Abasolo and Irapuato provided additional financial support for the work described in Mexico. The NSF GRFP funded the graduate studies of authors Andrea Naranjo-Soledad and Dana Hernandez at UC Berkeley. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Our study did not involve human subjects. No IRB was required. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data necessary for reproduction, validation, reanalysis, new analysis, and reinterpretation are included either in the main manuscript or the supporting information.