On Friday, the U.S. Food and Drug Administration (FDA) banned 19 chemicals used in antibacterial soaps. The agency said manufacturers had failed to prove such products — which have been on the market for more than 50 years — were either effective at preventing infections or safe to use.
Manufacturers will have one year to remove the ingredients from their products.
“Consumers may think antibacterial washes are more effective at preventing the spread of germs, but we have no scientific evidence that they are any better than plain soap and water,” said Dr. Janet Woodcock, director of the FDA’s Center for Drug Evaluation and Research, in a released statement. “In fact, some data suggests that antibacterial ingredients may do more harm than good over the long-term.”
About 40 percent of antiseptic hand soaps contain the banned ingredients. The most common of these chemicals are triclosan, used primarily in liquid soap, and triclocarban, used mainly in bar soaps.
Triclosan has been added to hand soaps since the mid-1960s. A 2013 University of Minnesota study found high levels of the chemical in the state’s lakes and other water sources — a troubling discovery since animal studies have shown triclosan to be a hormone disruptor.
In 2014, Minnesota became the first state to ban products containing triclosan, although the legislation does not go into effect until this coming January.
A global health problem
Both triclosan and triclocarban do kill bacteria, but, as the FDA’s new ruling makes clear, that ability doesn’t mean the products protect people from getting sick.
Knowledge about antibacterial soaps’ ineffectiveness has actually been around for quite some time. A 2007 scientific review of 27 previous studies — some of which were conducted as far back as 1980 — found no evidence that the products were more effective than ordinary soap and water at either reducing bacterial levels on hands or at preventing symptoms of infectious illnesses.
In fact, the ubiquitous of these chemicals in our environment — one study found that 75 percent of Americans have triclosan in their urine — has led scientists to warn that they may be contributing to the development of antibiotic-resistant bacteria, which has become a serious and growing public health threat.
Until recently it was thought that triclosan acted indiscriminately—killing all bacteria in a number of ways—but now scientists know that it targets specific molecular pathways, acting more like an antibiotic For example, triclosan homes in on an enzyme that plays a key role in bacterial metabolism — the same pathway that the tuberculosis-fighting antibiotic isoniazid targets. This similarity has raised concerns that bacteria could mutate and grow resistant to triclosan — and therefore also to the antibiotic.
Allison Aiello, an epidemiologist at the University of North Carolina at Chapel Hill, notes that several studies have shown that bacteria can become resistant to triclosan in a laboratory setting. For instance, one study found that up to 7 percent of Listeria strains isolated from the environment and food products were resistant to chemicals found in antibacterial soaps.
Not all products
The FDA’s new rule does not affect hand sanitizers or antibacterial wipes. Nor does it apply (yet) to the chemicals benzalkonium chloride, benzethonium chloride and chloroxylenol. Manufacturers of products with those three chemicals have a bit longer to submit safety and effectiveness data to the agency.
The ruling also does not apply to antibacterial soaps used in hospitals, nursing homes or other health-care settings.
FMI: You can read the FDA’s Consumer Update on antibacterial soap on the agency’s website. For a quick refresher course on the most effective way to wash your hands, check out the Centers for Disease Control and Prevention website. (Major tip: Scrub your plain-soap-lathered hands for at least 20 seconds, or the length of time it takes you to hum the song “Happy Birthday” — twice.)