Triclosan gets up your nose
21 Jul, 2014
The latest damning research on household antimicrobial products has found that triclosan, an antimicrobial agent found in common household liquid soaps, body washes, deodorants, shampoos, mouthwashes, toothpastes and even fabric and plastic, is finding its way inside human noses.
It seems to be promoting the colonisation of resistant Staphylococcus aureus, potentially predisposing some people to a range of infections, some of them life threatening, associated with the bacteria – ironically, almost the opposite effect that such products are supposed to have.
Triclosan commonly found in adult nasal secretions
Researchers at the University of Michigan reported in their published paper that triclosan is now commonly found in the nasal secretions of adults, and the presence of triclosan trends positively with nasal colonisation by S. aureus –an opportunistic pathogen that now colonises the noses and throats of approximately 30% of the population. “We demonstrate that triclosan can promote the binding of S. aureus to host proteins such as collagen, fibronectin and keratin as well as inanimate surfaces such as plastic and glass. Lastly, triclosan-exposed rats are more susceptible to nasal colonization with S. aureus. These data reveal a novel factor that influences the ability of S. aureus to bind surfaces and alters S. aureus nasal colonization.”
Triclosan has been in use for almost four decades, initially within hospital settings, but in the last 10 years, it has been incorporated into many antibacterial household products. A senior member of the research team, Professor Blaise Boles, an assistant professor of molecular, cellular and developmental biology at the university, said in a press release that previous studies have found traces of triclosan in human fluids including serum, urine and breast milk, and studies in mammals have found that high concentrations of triclosan can disrupt the endocrine system and decrease heart and skeletal muscle function.
“It’s really common in hand soaps, toothpastes and mouthwashes but there’s no evidence it does a better job than regular soap,” says Professor Boles.
Professor Boles says he would like to conduct a more broad survey to determine if triclosan is influencing microbial colonisation at additional human body sites.
Triclosan also linked to environmental contamination
Their findings, published in early April by mBio (an open-access journal of the American Society for Microbiology), add fuel to the fire following an earlier announcement by University of Minnesota researchers that increasing levels of triclosan were building up in the sediments of several lakes. Apparently, the chemical can break down into harmful dioxins that can damage aquatic ecosystems. Dioxins are also linked to cancer in humans.
“In light of the significant use of triclosan in consumer products and its widespread environmental contamination, our data combined with previous studies showing impacts of triclosan on the endocrine system and muscle function suggest that a re-evaluation of triclosan in consumer products is urgently needed,” the Michigan authors wrote.
The state of Minnesota is the first to take action on the findings, with a bill signed in May to prohibit the use of triclosan in retail consumer hygiene products. The bill, while representing relatively quick action, doesn’t come into effect until 2017.
New Zealand company removes triclosan from its products
In New Zealand, triclosan is legal and added to many products. However, company API Consumer Brands, which manufactures the Health Basics range, took the unusual move late last year of volunteering to remove triclosan from its hand and body washes in the interests of consumer and environmental health.
New Zealand scientists have also commented recently regarding the use of antimicrobial household products.
Get news article: Global report on antimicrobial resistance
Syed, A.K., Ghosh, S., Love, N.G. and Boles, B.R. (2014). Triclosan promotes Staphylococcus aureus nasal colonization. mBio, 5(2): e01015-13. doi:10.1128/mBio.01015-13. Open-access article available online at http://mbio.asm.org/content/5/2/e01015-13
- 21 July 2014