Microbiological Hazards of Household Toilets: Droplet Production and the Fate of Residual Organisms


Large numbers of bacteria and viruses when seeded into household toilets were shown to remain in the bowl after flushing, and even continual flushing could not remove a persistent fraction. This was found to be due to the adsorption of the organisms to the porcelain surfaces of the bowl, with gradual elution occurring after each flush. Droplets produced by flushing toilets were found to harbor both bacteria and viruses which had been seeded. The detection of bacteria and viruses falling out onto surfaces in bathrooms after flushing indicated that they remain airborne long enough to settle on surfaces throughout the bathroom. Thus, there is a possibility that a person may acquire an infection from an aerosol produced by a toilet.

Charles P. Gerba, Craig Wallis and Joseph L. Melnick
Department of Virology and Epidemiology, Baylor College of Medicine, Houston, Texas 77025

Appl Environ Microbiol. 1975 August; 30(2): 229-237
Copyright © 1975 American Society for Microbiology. All Rights Reserved.