The U.S. Food and Drug Administration (FDA) issued a rule Sept. 2 banning 19 antibacterial chemicals as ingredients in over-the-counter (OTC) antibacterial hand and body washes. Development of the final rule was informed by research that included several studies from scientists supported by the NIEHS Superfund Research Program (SRP).
FDA said that manufacturers did not show that OTC antibacterial soaps are both safe for long-term daily use and more effective than plain soap and water for preventing illness and spread of infection. The final rule, which takes effect Sept. 6, 2017, bans the sale of any OTC consumer soaps and body washes containing any of the banned chemicals, including triclosan and triclocarban, unless the product undergoes approval as a drug.
SRP findings cited in proposed rule
The proposed rule, issued in 2013, reviewed the relevant literature, including a number of SRP studies that highlight the health effects of and widespread exposure to triclosan and triclocarban.
Isaac Pessah, Ph.D., at the University of California (UC), Davis SRP Center, led one cited study that showed how triclosan weakens heart and skeletal muscle activities in animal models. Bruce Hammock, Ph.D., director of the same center, led a study that found significant absorption of triclocarban from soap during showering. A 2012 SRP Research Brief provides more information on both papers.
Other published papers that informed the rule focused on the persistence of antibacterial chemicals in the environment. One SRP study, led by Rolf Halden, Ph.D., from the Arizona State University Center for Environmental Security, showed how triclosan contaminates wastewater and may harm aquatic organisms.
“The large-scale use of triclosan-containing products has not brought any measurable public health benefits, but instead resulted in environmental contamination of water, dust, soil, and biota in countries around the world,” Halden said in a Scientific American news release. Halden also published a feature in 2014 that presented a timeline of scientific evidence on the widespread contamination and health effects of triclosan and triclocarban, and the need to regulate these chemicals in the U.S.
Initial focus on high-volume consumer soaps
The FDA rule applies to high-volume OTC antibacterial soaps and body washes. Antibacterial soaps that are used in health care settings, such as in hospitals and nursing homes, are exempted.
"With chemicals in the environment, we seem to treat them as all evil or perfectly safe," said Hammock. "Since triclosan is used as a high volume chemical in hand soap, it is more important to phase out those products where the antibacterial ingredients have little demonstrated value, than to phase out low volume products where there has been some demonstrated benefit, such as surgical scrubs used in hospitals.”
Hand sanitizers and hand wipes are also currently exempted. In June 2016, FDA requested additional scientific data from manufacturers demonstrating that the active ingredients in hand sanitizers are safe and effective to reduce bacteria on skin.
Cherednichenko G, Zhang R, Bannister RA, Timofeyev V, Li N, Fritsch EB, Feng W, Barrientos GC, Schebb NH, Hammock BD, Beam KG, Chiamvimonvat N, Pessah IN. 2012. Triclosan impairs excitation-contraction coupling and Ca2+ dynamics in striated muscle. Proc Natl Acad Sci U S A 109(35):14158−14163.
Halden RU. 2014. On the need and speed of regulating triclosan and triclocarban in the United States. Environ Sci Technol 48(7):3603−3611.
Miller TR, Heidler J, Chillrud SN, DeLaquil A, Ritchie JC, Mihalic JN, Bopp R, Halden RU. 2008. Fate of triclosan and evidence for reductive dechlorination of triclocarban in estuarine sediments. Environ Sci Technol 42(12):4570−4576.
Schebb NH, Ahn KC, Dong H, Gee SJ, Hammock BD. 2012. Whole blood is the sample matrix of choice for monitoring systemic triclocarban levels. Chemosphere 87(7):825−827.
(Sara Mishamandani Amolegbe is a research and communication specialist for MDB Inc., a contractor for the NIEHS Division of Extramural Research and Training.)