Antibacterial soaps don’t seem to add any germ-killing power to plain old soap and water and in fact may have some health risks, the Food and Drug Administration said Monday.



So the agency is proposing a new rule that would force soap makers to prove that products with added antibacterial ingredients such as triclosan are safe and effective —something certain to be highly controversial.

They'll have a year to prove it, the FDA says. And they're encouraging public comment, too.

"To put it simply, we need to collect additional information from the companies that make these products so that consumers can be confident about their effectiveness and about their safety," the FDA's Dr. Sandra Kweder told reporters in a telephone briefing.

"Under the rule, manufacturers would be required to provide additional safety data for these products before they can be recognized as 'generally recognized as safe for use.'" Generally recognized as safe — GRAS for short — is a designation that covers ingredients that are broadly used and, as the name implies, safe in a wide variety of foods or products.

“The proposed rule covers only those consumer antibacterial soaps and body washes that are used with water. It does not apply to hand sanitizers, hand wipes or antibacterial soaps that are used in health care settings such as hospitals,” the FDA says in a blog post. The goal would be to have a final rule by September 2016, Kweder said.

It's not a new issue. The FDA started asking about triclosan in 1978. Environmental groups and some members of Congress, such as Massachusetts Democrat Edward Markey, have been calling for limits on the use of triclosan. The National Resources Defense Council (NRDC) sued and the FDA agreed last month to do something about triclosan by 2016.

“It’s outrageous that FDA has waited 35 years to protect the public from this harmful chemical. This final rule should prohibit triclosan from use in soaps,” Mae Wu, a lawyer for NRDC’s health program, said in November.

There’s no proof yet that triclosan is dangerous to people, the FDA says. But studies are ongoing and there are hints it could be.

“Animal studies have shown that triclosan may alter the way hormones work in the body," the agency said. While animal studies don't always predict a problem for humans, the FDA said the studies "are of concern to FDA as well, and warrant further investigation to better understand how they might affect humans."

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“In addition, laboratory studies have raised the possibility that triclosan contributes to making bacteria resistant to antibiotics. Such resistance can have a significant impact on the effectiveness of medical treatments.”

People will have 180 days to comment and the FDA is encouraging researchers from industry, academic institutions and elsewhere to submit any data they might have that will shed light on triclosan's safety and effectiveness.

The FDA did not say what has prompted the move to suggest a new regulation for triclosan, which is used in 93 percent of liquid products labeled "antibacterial" or "antimicrobial."

"The data that we are talking about are mostly animal studies," Kweder said. But some have shown the products can change hormone levels if ingested or absorbed — affecting estrogen and thyroid hormones, for instance.

It's also not clear if just using soap and then washing it off would expose people to enough of the chemical to have any ill effect.

But it's equally unclear whether adding these chemicals to products offers any benefit at all, Kweder said. "We want companies to actually test these products so consumers who purchase them know if there is any benefit at all over plain soap and water,'" she said.

And she said sometimes companies seem to be promoting these products in a misleading way, for instance, with pictures showing people who appear to have viral illnesses such as colds or the flu. Antibacterials do not affect viruses.

Kweder says at least 2,000 different soap products contain triclosan or some other antimicrobial agent. While they're popular, she says, "you can absolutely buy liquid soaps that don't have triclosan in them. I looked this weekend to be sure."

The proposed rule only affects hand soaps and body washes. Triclosan is often used in toothpaste and it's been shown to help kill germs that cause gum disease, Kweder said.

While more testing is needed to demonstrate whether triclosan can hurt people who wash their hands with it, Stuart Levy and colleagues at Tufts University have shown how it can help cause bacteria to mutate into forms than can resist the chemical's effects.

Triclosan breaks open the cell walls of bacteria, killing them. By the way, it takes several hours to do this, so triclosan can do little good in the time it takes to wash and dry hands, says Levy.

His team did experiments in the late 1990s that showed the bacteria could evolve just enough and make cell walls using a mechanism that bypassed triclosan's effects. "We grew bacteria in the presence of triclosan," Levy said. His other concern — what are millions of gallons of triclosan-treated soap going down drains doing to bacteria in sewers, lakes, rivers and the ocean?

The American Cleaning Institute defends the safety of triclosan and says it has given FDA numerous studies showing the chemical is effective.



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