Antibacterial soap no more effective than plain soap at reducing bacterial contamination, study finds

Authors suggest that advertisers and consumers review their beliefs about the effectiveness of antibacterial soaps

Using antibacterial soap when hand-washing is no more effective than using plain soap, scientists in Korea have discovered.

The study, published in the Journal of Antimicrobial Chemotherapy, examined the effect of triclosan (the most commonly used active antiseptic ingredient found in soap) on bacteria in two ways.

First, they examined the bactericidal effects of triclosan in soaps against all 20 strains; and second, they compared the ability of antibacterial and non-antibacterial soap to remove bacteria from human hands, by using 16 healthy adult volunteers.

The results of the study indicate that there is no significant difference between the effects of plain soap and antibacterial soap when used under ‘real life’ conditions.

The scientists recreated the conditions of hand washing by exposing the bacteria for 20sec at 22°C (room temperature) and 40°C (warm temperature) to triclosan with a concentration of 0.3% – the maximum allowed by law. There were significantly greater effects after nine hours, but not during the short time required for hand washing.

Dr M S Rhee, lead author of the paper, suggests that 'advertisement and consumer belief regarding the effectiveness of antibacterial soaps needs to be addressed'.