The U.S. Food and Drug Administration said on Thursday it was reviewing the safety of triclosan, a widely used antibacterial agent found in soap, toothpaste and a range of other consumer products.
The agency stressed there are no grounds to recommend any changes in the use of triclosan but said some recent studies merited a closer look.
One member of Congress, Massachusetts Democrat Edward Markey, called for strict limits.
"Despite the fact that this chemical is found in everything from soaps to socks, there are many troubling questions about triclosan's effectiveness and potentially harmful effects, especially for children," Markey said in a statement.
"I call upon the federal government to ban the use of triclosan in consumer soaps and hand-washes, products intended for use by children, and products intended to come into contact with food. In addition, I will soon introduce legislation to speed up the government's efforts to evaluate and regulate other substances that may pose similar public health concerns."
The FDA noted that there was no evidence that triclosan could be harmful to people but noted that an animal study showed the chemical may alter hormone regulation and several other lab studies showed that bacteria may be able to evolve resistance to triclosan in a way that can help them also resist antibiotics.
Other studies have shown no evidence this has actually occurred in nature, however. Nonetheless, the Environmental Protection Agency has said it will speed up its planned review of triclosan.
"FDA does not have sufficient safety evidence to recommend changing consumer use of products that contain triclosan at this time," the agency said in a statement posted here
The Soap and Detergent Association has repeatedly defended the safety of triclosan, which has been in use for about 30 years.
One environmental group welcomed the FDA's announcement.
"It's about time FDA has finally stated its concerns about antibacterial chemicals like triclosan," said Dr. Sarah Janssen of the Natural Resources Defense Council.
"The public deserves to know that these so-called antibacterial products are no more effective in preventing infections than regular soap and water and may, in fact, be dangerous to their health in the long run."
Many experts agree that soap containing triclosan does little or nothing extra to remove bacteria that using soap without the ingredient, as washing the hands physically removes the excess bacteria.