Triclosan is one of the most widely used antimicrobials and is incorporated in thousands of consumer products, including hand soaps, toothpastes, body wash, kitchenware and even some toys. Millions of pounds of the chemical are used in the US each year.

The general population is exposed to triclosan because of its prevalence in a variety of daily care products as well as through waterborne contamination. Triclosan is linked to a multitude of health and environmental effects, ranging from cancer to endocrine disruption and impaired muscle contraction to effects on aquatic ecosystems. Triclosan is one of the top ten pollutants found in US rivers.

A study by Yueh et al, published in PNAS, the Proceedings of the National Academy of Sciences, found that triclosan, a broad-spectrum antibacterial chemical used in a wide range of consumer products including soaps, cosmetics, therapeutics, and plastics, was capable of promoting liver tumors.

See a review by Dinwiddie et al, published in the International Journal of Environmental Research and Public Health, for more on the the role of triclosan in cancer development.

In a study by Buth et al, published in the journal Environmental Science and Technology, triclosan was also shown to transform into dioxins in an aqueous solution, which has profound implications for both human health and the environment.

There is evidence that triclosan may aggravate inflammation in the gut and promote the development of colon cancer by altering gut microbiota.