Test tube experiments carried out at the universities on laboratory animals showed reduced physical function, tests on isolated heart and skeletal muscle showed impaired muscle contractions at a cellular level and experiments on fish showed reduced muscle movement and mobility.
The experiments were carried out as a joint research project and the results were published online in the peer reviewed Proceedings of the National Academy of Sciences of the United States.
Triclosan is pervasive in households
"Triclosan is found in virtually everyone's home and is pervasive in the environment," said Isaac Pessah, professor and chair of the Department of Molecular Biosciences in the UC Davis School of Veterinary Medicine, who also led the study.
"These findings provide strong evidence that the chemical is of concern to both human and environmental health."
According to the researchers notes, the dosages used in the experiments were matched to that found in the list of personal care products, to assimilate regular consumer use as much as possible.
The test tube experiments focused on the effects of triclosan on molecular channels in muscle cells, where the follow of calcium ions, which dictate muscle contractions.
The experiments found that with the presence of triclosan, the normal communication of proteins that functions muscle movement was impaired, leading to skeletal and cardiac muscle failure, the researchers said.
Impairment of heart and muscle function
This impairment of function in heart and skeletal muscle of laboratory animals was also reported, with anesthetized mice having a 25 percent reduction in heart function within 20 minutes of being exposed to the chemical.
"The effects of triclosan on cardiac function were really dramatic," said Nipavan Chiamvimonvat, professor of cardiovascular medicine at UC Davis and a study co-author. "Although triclosan is not regulated as a drug, this compound acts like a potent cardiac depressant in our models."
The scientists involved in the study said that the experiments gave reason to believe that exposure to triclosan in patients with underlying heart failure could have ‘significant effects’ because the chemical is so widely used, however, they did also say that additional studies would have to be undertaken to provide stronger evidence of this.
"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."
Although there have been a number of studies pointing to concerns over Triclosan, the American Cleaning Institute has counterbalanced this by pointing to science-based research showing it is safe to use, as well as a preliminary screening earlier this year by Health Canada and Environmental Canada, in which officials reiterated that the substance was safe.