Antimicrobial from soaps promotes bacteria buildup in human noses An antimicrobial agent found in common household soaps, shampoos and toothpastes may be finding its way inside human noses where it promotes the colonization of Staphylococcus aureus bacteria and could predispose some people to infection. Researchers at the University of Michigan report their findings this week in a study published in mBio ®, the online open-access journal of the American Society for Microbiology. Triclosan, a human-made compound used in a range of antibacterial personal care products such as soaps, toothpastes, kitchen surfaces, clothes and medical equipment, was found in nasal passages of 41% of adults sampled. A higher proportion of subjects with triclosan also had S. aureus colonization. S. aureus could promote infection in some populations such as people undergoing surgery. Triclosan has been around for the past 40 years, says senior study author