lavender-tea-tree- hormone-disruptor

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Is Lavender and Tea Tree Oil Safe for Young Boys?

There is a rarely a day that goes by that I don’t see a comment in a forum or on a social media post that states Lavender and Tea Tree (or Melaleuca) essential oils shouldn’t be used with young boys because they have been shown to be estrogenic or endocrine disruptors.

And it’s stated as if it’s fact–which further research into this issue would indicate it’s far beyond fact. Is it a myth? Maybe. Probably more like a misconception, but not enough research has been done.

So let’s dive into where this idea came from.

Lavender and Tea Tree Essential Oils as Endocrine Disruptors

In 2007, a study was published which suggested that repeated topical exposure of products containing lavender oil and/or tea tree (melaleuca) oil may be hormone disruptors.

The study was conducted after 3 boys, ages 4-10 and all in Colorado, presented signs of gynecomastia (enlarged breast tissue), and the only common link found between them was they had all been using commercial products containing lavender and tea tree oils. In each case, the breast growth was reduced within several months of ceasing to use these products.

As a result, researchers conducted in vitro (test tube) laboratory tests that showed both lavender and tea tree oil had weak estrogenic effects.

The Study’s Flaws

  • Actual products used by the boys were not named; therefore, the ingredients contained in them are unknown and can’t be tested by other parties to see if the findings are the same. It’s not even known if constituents of lavender or tea tree were actually detectable in the products.
  • The quantities of essential oil constituents that may have been adsorbed into the skin is unknown. Absorption of essential oils via wash off product (ie. shampoo, soap) is usually negligible because the time of skin contact is so short.
  • The study does no mention whether the boys may have been exposed to other known endocrine distributors like pesticides, pthalates, parabens, BPA exposure etc.
  • No further attempt was made to determine whether the cases were caused by localized environmental factors (ie. pesticides or dioxins found in the environment or food) since all cases were found in Colorado.
  • In vitro testing does not necessarily mean it will be replicated in vivo (meaning testing something in a tube vs an actual living organism). Further testing would need to be done.
  • It’s possible the plastic used in the test tube study could have contaminated the essential oil samples since oils act as a solvent and can leach chemicals into certain plastics.

Subsequent Research

A test conducted in 2013 tested lavender oil applied to the uterus of estrogen-deprived female rats over three days. It was applied to the skin at 4% and 20% concentration. According to those who conducted the test, these concentration were 6,000 and 30,000 times greater than normal skin exposure from multiple cosmetic products.

The test showed no evidence of estrogenic activity in the rats.


Based on the research we have available to us, it’s unlikely that lavender and tea tree (melaleuca) essential oils cause hormone disruption when exposed to aromatherapy doses of the oils. However, it seems that everyone agrees more research needs to be done to know for certain.

Robert Tisserand, the author of Essential Oil Safety, even goes as far to say, ” 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.”

You can also read his rebuttal to the study published by NAHA (National Association for Holistic Aromatherapy) HERE.

Salvatore Battaglia, author of The Complete Guide to Aromatherapy, also noted, “…while I do not refute that the cosmetic products that Henley et al. tested were responsible for the boys’ gynaecomastia, there is absolutely no sound clinical and scientific evidence that can link this to lavender and tea tree essential oils. It is very likely to have been triggered by contaminants or other ingredients…”

For more information on using oils safely, check out my FREE Essential Oils Safety Guide in my Resource Library.