Every day, millions of people use soaps and body washes that are labeled as being antibacterial or antimicrobial. Much of the proliferation of these products appears to be due to the marketing efforts of their manufacturers. Makers of these products have convinced us that using these products demonstrates concern for our family’s welfare as well as our own personal health.
Despite their widespread use, there is very little evidence to support the use of these products over the time-honored practice of washing with soap and water. Recently, the Food and Drug Administration (FDA) has proposed a ruling that would require manufacturers of these products to demonstrate their safety and effectiveness. If adopted, products that are not shown to be superior to non-antibacterial soaps in preventing human illness or reducing infection will be taken off the market. The proposed rule covers only household soaps and body washes and does not apply to hand sanitizers or antibacterial soaps used in the health care setting.
What makes a soap antibacterial? Most commonly, soaps labeled “antibacterial” or “antimicrobial” contain the chemicals triclosan or triclocarban. These are added to the soap in an effort to reduce or prevent bacterial contamination. Although they have not been confirmed to be hazardous to humans, recent studies have brought up concerns regarding exposure to these chemicals.
What are the risks of exposure to triclosan? The primary concerns regarding the addition of triclosan to common soap relate to: 1) alteration in hormone levels in animal models and 2) the possibility that use of triclosan could contribute to the development of “super bugs”, bacteria that are resistant to antibiotics. In regard to the first issue, some studies have shown that animals exposed to triclosan have developed reduced levels of thyroid hormone and testosterone. The concern regarding the development of resistant bacteria comes from the assumption that antimicrobial chemicals could act much in the same way as antibiotics. It is well known that bacteria exposed to an antibiotic can undergo genetic changes that reduce their susceptibility to the effects of that antibiotic. While triclosan has never conclusively been shown to cause the development of antibiotic resistant bacteria, the potential for the emergence of “super bugs” remains a serious concern.
Is there evidence to support the use of triclosan at all? In some instances, triclosan has been shown to be uniquely beneficial. For example, the manufacturers of a popular brand of toothpaste were able to convincingly demonstrate to the FDA that the addition of triclosan was effective in preventing gum infections. Evidence is currently lacking, however, regarding the benefits of triclosan in personal cleansing.