Skip to content

Read the labels on personal care products, and do NOT buy those with triclosan! (See earlier posts for other reasons to avoid triclosan.) From Science Daily:

The 'dirty' side of soap: Triclosan, a common antimicrobial in personal hygiene products, causes liver fibrosis and cancer in mice

Triclosan is an antimicrobial commonly found in soaps, shampoos, toothpastes and many other household items. Despite its widespread use, researchers report potentially serious consequences of long-term exposure to the chemical.The study, published Nov. 17 by Proceedings of the National Academy of Sciences, shows that triclosan causes liver fibrosis and cancer in laboratory mice through molecular mechanisms that are also relevant in humans.

"Triclosan's increasing detection in environmental samples and its increasingly broad use in consumer products may overcome its moderate benefit and present a very real risk of liver toxicity for people, as it does in mice, particularly when combined with other compounds with similar action," said Robert H. Tukey, PhD, professor in the departments of Chemistry and Biochemistry and Pharmacology. 

Tukey, Hammock and their teams, including Mei-Fei Yueh, PhD, found that triclosan disrupted liver integrity and compromised liver function in mouse models. Mice exposed to triclosan for six months (roughly equivalent to 18 human years) were more susceptible to chemical-induced liver tumors. Their tumors were also larger and more frequent than in mice not exposed to triclosan.

The study suggests triclosan may do its damage by interfering with the constitutive androstane receptor, a protein responsible for detoxifying (clearing away) foreign chemicals in the body. To compensate for this stress, liver cells proliferate and turn fibrotic over time. Repeated triclosan exposure and continued liver fibrosis eventually promote tumor formation.

Triclosan is perhaps the most ubiquitous consumer antibacterial. Studies have found traces in 97 percent of breast milk samples from lactating women and in the urine of nearly 75 percent of people tested. Triclosan is also common in the environment: It is one of the seven most frequently detected compounds in streams across the United States.

More about this study plus a discussion about the FDA's lack of action. From The Atlantic:

The Ingredient to Avoid in Soap

Breast milk contains hundreds of species of bacteria.From the December 8, 2013 Scientific American:

The bacteria in breast milk

Several recent studies have found that breast milk contains a healthy dose of commensal bacteria; all the staphylococci, streptococci, and lactic acid bacteria that are found in the infant gut. This isn’t just bacteria from the skin which have contaminated the samples, but bacteria that have come from inside the breast as an integral component of the milk.

In a study of 16 women it was found that while each milk sample contained hundreds of different bacterial species, around half of the microbiotic community was made up of nine species present in all samples. The other half varied from person to person. This pattern is also found in human gut microbes; a core set present in all individuals along with a large diversity of separate species to make up a unique individual microbiome.

So how do bacteria get into breast milk? Some of them may come from the mouth of the baby. During feeding the skin of both the mother and baby will be in contact with the baby’s open mouth and a certain amount of flow-back can occur between the mouth and nipple. More excitingly it’s been suggested that immune cells in the mothers gut may be able to pick up bacteria and carry them around the body using the lymphatic system. The lymphatic system is a network of vessels used to transport blood plasma. It’s a main highway for immune cells inside the body and is also involved in the absorption and transports of fats.

Like all humans, infants have a range of bacteria within their gut. It looks like these bacteria are initially supplied from the mother’vaginal and skin bacteria, before being replaced by bacteria from the breast milk. Researchers also found that when babies started eating solid food a whole new range of bacteria was introduced, forming the gut microbiome that persisted into adulthood.