Antibacterial Soap No Better Than Regular Soaps: Study

A recent study proves that antibacterial soaps are not more effective in killing germs and other bacteria than regular soaps.

LiveScience reports that a recent study published online in the Journal of Antimicrobial Chemotherapy has examined that efficacy of triclosan, an antiseptic agent used widely in soaps, and has found that contrary to how it is presented in advertisements, antibacterial soaps are no better than regular soaps in killing and washing off germs and other bacteria.

In the background information of the study, the researchers noted a 2013 declaration by the US Food and Drug Administration that soap companies must provide data showing proof of the efficacy of antibacterial soaps in killing germs, compared to regular hand soaps, or even just plain water. As such, the researchers wanted to investigate the effectiveness of the legally approved triclosan, the common antiseptic found in antibacterial soaps.

For the study, the researchers used plain soap and antibacterial soap (with the same formulation as plain soap, but containing 0.3 percent triclosan, which is the law-approved maximum amount). Simulating real-life conditions, twenty bacterial strains proposed by the FDA were exposed to both soaps for 20 seconds, at two different temperatures: room temperature (22°C), and warm temperature (40°C ).

The soaps' effectiveness in decontaminating was also examined "in vivo," having 16 adult volunteers' hands doused with the Serratia marscescens bacteria.

Test results showed that there was no big difference in how both soaps killed or eliminated the bacteria, given the time period, at both test temperatures. This means that regular soaps can do the cleaning that usually, only antibacterial soaps have been publicly promoted to do.

Also, it was found that if the bacteria would be exposed to triclosan for a longer time—nine hours, to be exact—the bacteria would be significantly killed. This just shows that actually, triclosan can be effective in eliminating germs and bacteria that are reported to cause diseases.

However, its antiseptic effects are not apparent in real-life handwashing situations where washing takes just a short amount of time.

"This study shows that presence of antiseptic ingredients (in this case, triclosan) in soap does not always guarantee higher anti-microbial efficacy during hand washing," Min-Suk Rhee, a researcher of food bioscience and technology at Korea University in Seoul, South Korea, told Live Science. Rhee is the study's senior author.

Rhee explained study results suggest that soap companies should scale back their claims that antibacterial soaps clean better than regular soaps.

"If the manufacturer would like to advertise the antiseptic efficacy of their products, they should supply scientific evidence to support the claims," said Rhee.