There is no significant difference in bactericidal activity between plain soap and antibacterial soap: This was the conclusion of a recently presented scientific review, that we want to present on the occasion of the Global Handwashing Day (October, 15). With Dr. Taejin Cho, member of the researching team, spoke Carola Timmel.
The beginning of the research goes back to 2013. At that time the US Food and Drug Administration (FDA) proposed a rule stating that manufacturers must provide data to demonstrate that antibacterial soap is more effective than plain soap or water. The objective of the study (Department of Food Bioscience and Technology, College of Life Sciences and Biotechnology, Korea University, Seoul) was to examine the in vitro and in vivo bactericidal effect of triclosan in soap. Triclosan is the most widely used antiseptic agent in soap.
Twenty bacterial strains – proposed by the FDA – were exposed to plain and antibacterial soaps (the same formulation as plain soap, but containing 0.3% triclosan) for 20 seconds at 22°C room temperature and 40°C warm temperature. The decontamination efficacy of plain soap and antibacterial soap was also examined in vivo: the hands of volunteers were artificially inoculated with bacteria.
The results were astonishing: There was no significant difference in bactericidal activity between plain soap and antibacterial soap at either test temperature. However, antibacterial soap showed significantly greater bactericidal effects after nine hours. These results suggest that although triclosan-containing soap does have antibacterial activity, the effects are not apparent during the short time required for hand washing.
“The present study provides practical information that may prove useful for both industry and governments”, say Taejin Cho, member of the researching team.