A recent article published in Science Translational Medicine highlights newly discovered harmful effects of triclosan, a common antimicrobial agent.
Many of our household items contain chemicals that may be carcinogenic, which describes a chemical’s ability to cause cancer, albeit at low levels that limit this effect due to policies and regulations. Nonetheless, scientific studies that examine the activities of common chemicals and how they damage the cells in our bodies is important to guide future policies to protect the health of consumers.
What is triclosan?
Triclosan is a chemical that is used as an antimicrobial ingredient in several products, including toothpaste, cosmetics, and toys. It is believed that the entire U.S. population is exposed to this chemical in almost all stages of life. Moreover, triclosan is one of the most common pollutants in the environment. It is known that triclosan can be harmful at high exposure levels, but not much is known about its effects in low doses.
A group from the U.S. sought to determine any potential negative effects on health from continued exposure to triclosan in animal models and recently published their findings in Science Translational Medicine.
Inflammatory effects of triclosan
The authors of the study firstly briefly exposed mice to low doses of triclosan, which was observed to cause colonic inflammation and worsen models of colon cancer. Furthermore, the scientists found that triclosan changes the composition of healthy gut bacteria to cause increased inflammation. Lastly, to investigate the mechanisms behind how the chemical induces inflammation, the authors used genetically altered mice that lack an important protein, TLR4, that signals in the immune system. These mice did not develop inflammation in the colon, so the authors suggested that TLR4 signalling is involved in the harmful effects of triclosan that were described in the study.
The results of this study demonstrate that this widely used antimicrobial ingredient has harmful effects on health even at low doses in animal models. The authors identified the roles of gut bacteria and TLR4 signalling in the inflammatory effects of triclosan.
Further examination into the activity of triclosan on our health is warranted so that we have a better understanding of the chemical. The data presented in this study, in addition to any future data on triclosan, could lead to major changes in federal agencies all over the world that regulate the use of triclosan and hopefully improve the safety and health of consumers.
Written by Branson Chen, BHSc
Reference: Yang H, Wang W, Romano KA, Gu M, Sanidad KZ, Kim D, Yang J, Schmidt B, Panigrahy D, Pei R, Martin DA. A common antimicrobial additive increases colonic inflammation and colitis-associated colon tumorigenesis in mice. Science Translational Medicine. 2018 May 30;10(443):eaan4116.