Laboratory assessment of a gravity-fed ultrafiltration water treatment device designed for household use in low-income settings

• Type of Material: Article
• Authors: Thomas Clasen, Emory University; Jaime Naranjo, University of Arizona, Tucson; Daniel Frauchiger, Vestergaard Frandsen S.A.; Charles Gerba, University of Arizona, Tucson
• Language: English
• Date: 2009-05
• Publisher: American Society of Tropical Medicine and Hygiene
• Publication Version: Final Published Version
• Copyright Statement: © 2009 The American Society of Tropical Medicine
• Final Published Version (URL): http://www.ajtmh.org/content/80/5/819.long
• Title of Journal or Parent Work: American Journal of Tropical Medicine and Hygiene
• ISSN: 0002-9637
• Volume: 80
• Issue: 5
• Start Page: 819
• End Page: 823
• Grant/Funding Information: Daniel Frauchinger is an employee of Vestergaard Frandsen S.A.; and the costs of the University of Arizona in performing the laboratory work reported in this work were funded by Vestergaard Frandsen S.A.
• Research Categories: Health Sciences, Public Health

Abstract

Interventions to improve water quality, particularly when deployed at the household level, are an effective means of preventing endemic diarrheal disease, a leading cause of mortality and morbidity in the developing world. We assessed the microbiologic performance of a novel water treatment device designed for household use in low-income settings. The device employs a backwashable hollow fiber ultrafiltration cartridge and is designed to mechanically remove enteric pathogenic bacteria, viruses, and protozoan cysts from drinking water without water pressure or electric power. In laboratory testing through 20,000 L (~110% of design life) at moderate turbidity (15 nephelometric turbidity unit [NTU]), the device achieved log10 reduction values of 6.9 for Escherichia coli, 4.7 for MS2 coliphage (proxy for enteric pathogenic viruses), and 3.6 for Cryptosporidium oocysts, thus exceeding levels established for microbiological water purifiers. With periodic cleaning and backwashing, the device produced treated water at an average rate of 143 mL/min (8.6 L/hour) (range 293 to 80 mL/min) over the course of the evaluation. If these results are validated in field trials, the deployment of the unit on a wide scale among vulnerable populations may make an important contribution to public health efforts to control intractable waterborne diseases.