"Triclosan is commonly found in antibacterial personal-care products such as hand soaps as well as deodorants, mouthwashes, toothpaste, bedding, clothes, carpets, toys and trash bags. The U.S. Environmental Protection Agency in 1998 estimated that more than 1 million pounds of triclosan are produced annually in the United States, and that the chemical is detectable in waterways and aquatic organisms ranging from algae to fish to dolphins, as well as in human urine, blood and breast milk.
In “test tube” experiments, triclosan impaired the ability of isolated heart muscle cells and skeletal muscle fibers to contract. Specifically, the team evaluated the effects of triclosan on molecular channels in muscle cells that control the flow of calcium ions, creating muscle contractions. Normally, electrical stimulation (“excitation”) of isolated muscle fibers under experimental conditions evokes a muscle contraction, a phenomenon known as “excitation-contraction coupling,” the fundamental basis of any muscle movement, including heartbeats. But in the presence of triclosan, the normal communication between two proteins that function as calcium channels was impaired, causing skeletal and cardiac muscle failure.
Because the chemical structure of triclosan resembles other toxic chemicals that persist in the environment, the FDA and the U.S. Environmental Protection Agency are conducting new risk assessments of the chemical. Based on their study outcomes, the researchers argue that the potential health risks call for greater restrictions.
“We have shown that triclosan potently impairs muscle functions by interfering with signaling between two proteins that are of fundamental importance to life,” said Pessah. “Regulatory agencies should definitely be reconsidering whether it should be allowed in consumer products.”
Said Hammock: “Triclosan can be useful in some instances, however it has become a ubiquitous ‘value added’ marketing factor that actually could be more harmful than helpful. At the very least, our findings call for a dramatic reduction in its use.”
Chemical widely used in antibacterial hand soaps may impair muscle function, UC Davis News and Information, http://news.ucdavis.edu/search/news_detail.lasso?id=10301 (Aug 2012)
Chemical widely used in antibacterial hand soaps may impair muscle function, UC Davis Health System, http://www.ucdmc.ucdavis.edu/publish/news/newsroom/68720 (Aug 2012)
"Triclosan impairs excitation–contraction coupling and Ca2+dynamics in striated muscle" http://www.biopestlab.ucdavis.edu/files/152120.pdf (July 2012)