Triclosan Antibacterial Soap No Better at Killing Germs Than Regular Soap

Soap with the antibiotic triclosan is no more effective than regular soap at killing germs, according to a new study. Mariana Bazo/REUTERS

Products marketed as "antibacterial soaps" give the impression that they might be better at killing microbes than regular soap. But new research suggests they don't actually do all that much that regular old soap doesn't.

A study published in the Journal of Antimicrobial Chemotherapy found that hand cleaners laden with the antibiotic triclosan are no more effective than regular soap at killing germs.

In the paper, researcher Min-Suk Rhee and colleagues from Korea University exposed 20 strains of bacteria to one formulation of regular soap and another containing 0.3 percent triclosan, which is the maximum amount allowed by law. The bacteria were exposed to these soaps for 20 seconds, simulating regular hand-washing conditions.

The scientists found that in terms of the amount of bacteria killed, there was no difference between the two. Only after nine hours did the triclosan-containing soap appear to have a significant effect in killing more germs than the regular stuff.

They also performed another experiment in which they asked 16 participants to use both soaps, before counting the number of bacteria that were then rinsed off their hands. Again, they found no significant difference between the two.

"Antibacterial activities of triclosan have been well documented. However, its risk remains controversial since various adverse effects have been reported, including allergen, antibiotic resistance, carcinogenic impurities and bioaccumulation," Rhee says. "Our study indicates there was no significant difference in antiseptic effects" between soaps that contain triclosan and those that don't.

Triclosan isn't exactly innocuous. The chemical is undergoing a safety review by the Food and Drug Administration for reputed ill health effects. These include skin rashes, allergic reactions and increasing the incidence of antibiotic-resistant bacteria. And if regular soap works just as well, buying soap with triclosan might not be worth the risk.