We've been hearing the question of endocrine disruption in lavender and tea tree oil since 2007, and we just got it again in response to our recommendation of organic skincare made with those particular essential oils. I can understand that it seems like a valid concern, especially when you consider that many natural skincare products are made with essential oils.
We investigated the question of estrogenic activity in lavender (and tea tree oil) and learned that the claim is completely unfounded.
Here's the research we received from our favorite herbalist, Melinda Olson (RN, herbalist, and founder of Earth Mama Angel Baby), along with clarification of the vast difference between essential oils and aromatherapy oils (highly concentrated volatile oils).
When concerns about the safety of lavender and tea tree oil first came out in 2007, we spent a great deal of time researching the reported issues about these time-tested essential oils. Since then, this story has circulated, and been the source of much confusion, misunderstanding and fear.
Here’s the back story: In 2007, two doctors released their opinion that two boys had developed gynecomastia, or enlarged breast tissue. The one apparent commonality was that they boys had both used care products containing lavender and/or tea tree oil. The doctors’ study did not, however, take into account any other factors that may have been the cause of the gynecomastia. They didn’t look at their lifestyle, environmental exposure, or diet. Were they eating meat or drinking milk contaminated with growth hormone? Were other known endocrine disruptors like BPA in their water bottles or canned foods? Were they eating foods heated in plastics? The study did not ask these questions. Nor has there ever been a subsequent evidence-based study to evaluate the validity of the conclusion that lavender and/or tea tree essential oil are the cause of gynecomastia in boys. Yet despite the lack of usual scientific practices or a large-scale control group, the study was widely published on the internet, causing much concern!
Another common misconception is the confusion between an essential oil used diluted in personal care products vs. being ingested or used undiluted on the skin. While they are called “essential oils”, aromatherapy oils are really highly concentrated volatile oils and not fixed oils like olive oil or canola oil. If left in an open container, essential oils that have no fat molecules will evaporate. Fixed oils will not. When reading about the safety of essential oils, be sure to note the mode of application – I’d never recommend anyone drink either lavender or tea tree essential oil. These plant oils have been used externally for thousands of years, and according to our research, it is our belief that they are safely used externally, when diluted in personal care products. There is, however, a plethora of evidence-based research to document their efficacy (plus they smell fantastic!).
You can learn more about the background on this misconception here.
P.S. Read your labels carefully and avoid products with “lavender fragrance” on the label. The term “fragrance” is a legal hiding place for up to 3,000 unknown chemicals.