The disinfection efficacy of a point-of-use water treatment system against bacterial, viral and protozoan waterborne pathogens

Morteza Abbaszadegan, Michaela N. Hasan, Charles P. Gerba, Peter F. Roessler, Barth R. Wilson, Roy Kuennen, Eric Van Dellen

Research output: Contribution to journalArticle

58 Scopus citations

Abstract

A point-of-use (POU) water treatment system (WTS), comprised of a pressed activated carbon block filter followed by an ultraviolet (UV) light reactor, was evaluated for microbial disinfection efficacy following the general guidelines of the United States Environmental Protection Agency Guide Standard and Protocol for Testing Microbiological Water Purifiers. The POU WTS was challenged against bacterial, viral and protozoan waterborne pathogens including Vibrio cholerae, Shigella dysenteriae serotype 2, Escherichia coli 0157:H7, Salmonella typhi, hepatitis A virus strain HM 175, poliovirus type 1 strain Lsc2ab, simian rotavirus SA11, Cryptosporidium parvum oocysts, Giardia lamblia cysts and coliphage MS2. The POU WTS was tested for the removal/inactivation of each challenge organism in separate 16- to 20-day test periods under various conditions of water quality, at the system's maximum recommended flow rate and at 70% of the lamps normal UV intensity. For each organism tested, microbial challenges were conducted over the course of the test period at 0, 50, 100 and 150% of the system manufacturer's rated water treatment capacity. Each microbial challenge consisted of 30 L of influent water containing approximately 105 bacterial cfu/mL, 104 viral pfu/mL or 103 protozoan cysts/mL. Inffluent and effluent water samples were taken during the challenges and assayed for the particular pathogen and the percent reduction calculated. Effluent water samples were also taken and assayed for the possible presence of the pathogens following two 60-h stagnation periods. The POU WTS was found to effectively remove and/or inactivate greater than 99.9999% of the bacterial pathogens, greater than 99.99% of the viruses and greater than 99.9% of the protozoan cysts and oocysts tested to 150% of the water treatment capacity of the POU WTS. These findings suggest that a properly designed and operated POU WTS may be a practical approach to removing microbiological waterborne pathogens from drinking water.

Original languageEnglish (US)
Pages (from-to)574-582
Number of pages9
JournalWater Research
Volume31
Issue number3
DOIs
StatePublished - Mar 1997

Keywords

  • Cryptosporidium parvum
  • Drinking water treatment
  • Escherichia coli
  • Giardia lamblia
  • Hepatitis A virus
  • Microbiological water purifier
  • Point-of-use water treatment system
  • Poliovirus type 1
  • Salmonella typhi
  • Shigella dysenteriae
  • Simian rotavirus SA11
  • Vibrio cholerae
  • Water disinfection

ASJC Scopus subject areas

  • Ecological Modeling
  • Water Science and Technology
  • Waste Management and Disposal
  • Pollution

Fingerprint Dive into the research topics of 'The disinfection efficacy of a point-of-use water treatment system against bacterial, viral and protozoan waterborne pathogens'. Together they form a unique fingerprint.

  • Cite this