Common soap, toothpaste ingredient linked to colon cancer

Food science study in mice suggests more scrutiny is warranted

Photo of tooth paste and brush
June 6, 2018

Food Science assistant professor Guodong Zhang and his team have found a common medicine cabinet ingredient could have adverse effects on colonic inflammation and colon cancer by altering gut microbiota.

The study reported in Science Translational Medicine suggests that short-time treatment with low-dose triclosan (used widely in hand soaps and toothpastes) caused low-grade colonic inflammation, and exaggerated disease development of colitis and colitis-associated colon cancer in mice. "These results, for the first time, suggest that triclosan could have adverse effects on gut health," says Zhang.

Two coauthors Haixia Yang and Weicang Wang—both from the Zhang laboratory at UMass Amherst—point out that triclosan is among the most widely used antimicrobial ingredients and is found in more than 2,000 consumer products. They note that a National Health and Nutrition Examination Survey showed that triclosan was detected in about 75 percent of the urine samples of individuals tested in the United States and it is among the top 10 pollutants found in U.S. rivers.

"Because this compound is so widely used, our study suggests that there is an urgent need to further evaluate the impact of triclosan exposure on gut health in preparation for the potential establishment of further regulatory policies," says Yang, a postdoctoral fellow in the Zhang laboratory.

In an editorial note accompanying the article, the journal says, "Triclosan exposure is practically unavoidable in the United States, but little is known how ingestion may affect our health." This study observed that triclosan altered mouse gut microbiota, increased inflammation, increased the severity of colitis symptoms and spurred colitis-associated colon cancer cell growth. Though limited to mouse models, "this work suggests that the effects of triclosan on human health should be examined more closely," editors noted.

Read on:
Original News Office release
Research article in Science Translational Medicine
More on Zhang's work