Have you heard that lavender and tea tree oil can cause little boys to grow breasts? Though I’ve definitely pulled out the lavender for my kids on many occasions and I use tea tree oil in my diaper wipe solution, there have been times when I’ve held back over concerns about possible estrogenic effects, both for them and myself.
Turns out, there was probably nothing to worry about.
Thanks to a tip from Paula on a Facebook post last week, I discovered that one of the foremost experts on aromatic oils – Essential Oil Safety co-author Robert Tisserand – has actually written an article on this subject.
Turns out, the often cited 2007 study which first claimed lavender and tea tree oil are hormone disruptors was it poorly constructed. Plus, it has a sample pool of only three people.
The boys (ages four, seven and ten), apparently used **some kind of product** which contained these oils. The products weren’t analyzed for the presence of other potential hormone disruptors, and the oils weren’t checked for purity. After developing their hypothesis, the researchers decided to test lavender and tea tree oil with human cells in a petri dish. Though the results did show estrogenic activity, that’s probably because the solvent they used to dilute the oils – dimethyl sulfoxide – is a known estrogen mimicker. Furthermore:
If you take a close look at the study, some issues are raised . . . The full list of ingredients in these products were not mentioned, nor the possible chemicals included in the packaging of the products. Parabens were likely included in the ingredients and phthalates in the packaging. In a recent study, diethyl phthalate was found in 103 out of 252 products, which included fragrances, hair care products, deodorants, nail polishes, lotions, skin cleansers and baby products.3 Both phthalates and parabens have been shown to have an estrogenicity presence.4&5”
Are Lavender and Tea Tree Oils Estrogenic?
Clearly, the results of this study are desperately lacking in meaningful analysis. So what do we know, really?
What Studies REALLY Say About Lavender & Tea Tree
According to three doctors representing Wake Forest, Yale and Harvard respectively, “Traditional use and clinical trials have not suggested estrogenic effects of tea tree or lavender oil, though estrogenic effects have been reported for other essential oils and plants.” (Source)
Even more helpful is this study, which measured the effects of lavender when applied to skin – a method that is particularly relevant since that it often how it is used in therapeutic situations. The study – which used a test that is “regarded as the ‘benchmark animal assay for estrogenic effects'” – found that the lavender had no estrogenic effect even in concentrations 6,000 and 30,000 times greater than estimated exposure from multiple cosmetic products containing lavender oil. (Source: Robert Tisserand)
Zip. Nada. Nothing.
Tisserand concludes that “Lavender oil does not mimic estrogen nor does it enhance the body’s own estrogens. It is therefore not a ‘hormone disruptor’, cannot cause breast growth in young boys (or girls of any age), and is safe to use by anyone at risk for estrogen-dependent cancer.”
In another article, he examines the claims against tea tree and concludes that “in the case of tea tree oil, for example, the estrogen-like compounds do not penetrate human skin, and a hormonal effect from dermal application of the oil is therefore impossible.”
Personally, I am comfortable using tea tree and lavender with my children, but of course it’s totally fine to skip them if you’re concerned. Chamomile is an excellent alternative to lavender, and you can find a longer list of child-friendly essential oils here.
Are you concerned about the potential estrogenic effects of lavender and tea tree? Why or why not?