In many developing countries such as Guatemala, access to safe drinking water is very limited. Many sources of water that are available are contaminated with bacteria, particularly Escherichia coli and other coliform bacteria. In order to provide a means of obtaining safe drinking water in developing countries, various methods of treating water at the household level have been developed and implemented throughout the world. One of the more promising treatment mechanisms is the ceramic pot filter, which is typically applied with colloidal silver because of it supposed disinfection purposes. During this study, the bacteria removal effectiveness of 30 filters without colloidal silver was determined by adding water contaminated with Escherichia coli to the filters, and then measuring bacteria concentrations in the filter effluent. The average log reduction values of E. coli and total coliforms determined in this study are 2.1 and 2.3, respectively, and are comparable to other studies of bacteria removal of CPFs. This situation suggests that colloidal silver may indeed not be necessary for the filters to effectively remove bacteria from source water. This study was completed in a period of two weeks, however, while the effect of silver may provide disinfection for several months of use.
Keywords: bacteria, ceramic pot filters, drinking water, filtration, point of use, silver