Every time you wash your hands using antibacterial soap you probably feel good because you're not spreading bugs. But check the bottle and you'll probably find the soap contains triclosan—a chemical that has just been shown to impair muscle function in humans.
Research published in the Proceedings of the National Academy of Sciences suggests that triclosan hinders human muscle contractions at the cellular level, as well as inhibiting muscle function in both fish and mice. Isaac Pessah, one of the researchers, told Smithsonian:
"Triclosan is found in virtually everyone's home and is pervasive in the environment. These findings provide strong evidence that the chemical is of concern to both human and environmental health."
The study investigated how triclosan affected human heart and skeletal muscle cells in the lab. They found that it disrupted communication between proteins which allow the muscles to function, in turn causing failure of both types of cells. They backed up those experiments with tests on fish and mice. The mice showed reductions in heart muscle function by as much as 25 percent, and a reduction of grip strength of 18 percent. The fish became less effective swimmers after exposure to triclosan.
So what's to do? There's no denying that the chemical has some negative effects on muscle function, and the researchers are genuinely concerned about the health risks it poses. Nipavan Chiamvimonvat, another of the researchers, explained to Smithsonian:
"The effects of triclosan on cardiac function were really dramatic. Although triclosan is not regulated as a drug, this compound acts like a potent cardiac depressant in our models."
Meanwhile, the FDA has declared that there's no evidence to suggest that using antibac soaps with triclosan offer any health benefits over just washing with conventional soap and water. So, for now at least, it might pay to ditch your fancy handwash. [PNAS via Smithsonian]
Image by SCA Svenska Cellulosa Aktiebolaget under Creative Commons license