Researcher Looking at bulk-soap refillable dispensers, researchers from BioScience Laboratories in Montana and the University of Arizona found that liquid soap can become contaminated with microbes, which could then be passed on to individuals using the soap. According to the researchers, several health outbreaks have already been attributed to the use of such dispensers.
To test the effects of contaminated soap, the researchers sourced an elementary school where 14 soap dispensers had been found to be contaminated with pathogenic microorganisms. They then asked students and staff to wash their hands and measured bacteria levels on their hands before and after their handwashing. The number of bacteria increased 25-fold after washing with the soap. From there, of course, the bacteria could easily spread to other surfaces – door handles, counter tops and so on. All the study participants were then given appropriate hand sanitiser to ensure the germs weren’t passed on. The contamination problem does not occur when the soap dispenser is filled using a sealed-soap refill.
If you have to use a toilet where you’re not sure of the soap, stick with water and wash your hands for longer. Researchers from the UNC School of Public Health US, who looked into various different types of hand-sanitising methods, maintained that effective removal of bacteria from hands is probably due to the physical washing off of germs. Their 2005 study found that 10 seconds of washing with soap and water is just as effective as using sanitisers, and that alcohol rubs and washing with only water is nearly as good as washing with soap and water.
First published May 9, 2011