Water purification system microbiological evaluation in health care environment

Abstract

Purified water is used in the production of commercial preparations, pharmaceutical applications, cleaning of semi-critical devices, areas and equipment, as well as in the preparation of pharmaceutical chemicals and bacteriological media. The maintenance of water purification systems requires routine cleaning and disinfection of each stage of the system to remove accumulated particulate matter and to prevent bacterial growth. Contaminants commonly found in feed water decrease the efficiency of the system and increase the cost of producing purified water. The water purification system used in this study comprises four main steps: pretreatment, purification, storage and distribution of purified water. Total coliform viable counts were enumerated in minimal R2A agar and m-Endo agar medium. Cleaning and sanitization of the purification system stages were performed periodically, or when the system was stopped longer than 24 hours. The contamination of water was verified in all the treatment steps for the system studied, especially in the activated carbon. The most part of contamination was eliminated by reverse osmosis. These process generate 40% waste water. In order to take the advantage of these waste waters, the Pilot Unit Beneficiation Water (WBPU) has been proposed. It plans to apply ultraviolet radiation and ozone gas to eliminate contamination from waste waters, rather than the chlorination, which damage the reverse osmosis membrane. These waste waters can be used to mix with the rain waters to pH values adjust.