Evaluation of Point of Use (POU) Systems for the Removal of Microbiological Contaminants in Drinking Water

As a final barrier before consumption, properly designed and operated Point-of-Use (POU) treatment systems are important for safe drinking water supplies. POU treatment devices have gained importance for protection against intentional or accidental contamination of drinking water supplies. The events of September 11, 2001 have further emphasized the importance of POU devices in this regard. This paper summarizes the results of pilot-scale studies that were conducted at the U.S. Environmental Protection Agency's (EPA's) Test and Evaluation (T&E) Facility in Cincinnati, Ohio, to evaluate the performance of three different POU systems for removing microbiological contaminants in drinking water. Two of these systems were based on filtration through electrostatically charged media and the third system incorporated a reverse osmosis (RO) membrane. The systems were challenged with a number of microbiological contaminants including Cryptosporidium, E. coli, MS2 bacteriophage, B. subtilis and polystyrene latex (PSL) beads (as a surrogate for Cryptosporidium). The results demonstrated that these POU systems were effective in removing the target biological contaminants in accordance with the standards presented in the U.S. EPA "Guide Standard and Protocol for Testing Microbiological Water Purifiers".