Australian researchers exposed E. coli bacteria to triclosan (an antimicrobial used in personal care products like toothpaste, shaving cream, and face masks) for 30 days. They found that the chemical made the bacteria resistant to several antibiotics.
The scientists focused on triclosan because it’s an emerging contaminant that has been detected in various water sources, says lead study author Jianhua Guo, Ph.D., a senior research fellow at the University of Queensland’s Advanced Water Management Centre in Brisbane, Australia. They found that the chemical caused genetic mutations at 100 times the rate that would naturally occur, which led to the development of antibiotic resistant bacteria.
THE BOTTOM LINE
In December 2017, the FDA ruled that triclosan is not generally recognized as safe and effective—a category reserved for additives with no data to back up their benefits. The effects of short-term exposure are unclear, but Guo says there's definitely a risk of antibiotic resistance, "a major threat to people," in the long term. Use triclosan-free hygiene products to stay on the safe side.