Are there any dangers associated with the use of essential oils?

Whether taken orally or applied topically, during the first trimester of pregnancy, essential oils should be avoided. Some should be avoided throughout the entire pregnancy, while others can be used after the first four months.

The primary risk is associated with the neurotoxic potential of certain essential oils, particularly the ketones they contain. These compounds can cause nervous or respiratory spasms, as well as nausea which can increase the risk of miscarriage. Furthermore, it is possible that the active ingredients in essential oils can cross the skin barrier and the placenta, affecting the developing embryo.

A compound is referred to as dermocaustic when it causes irritations or even burns on the skin and mucous membranes.

The molecules involved in these types of reactions are most commonly the carvacrol (essential oil from oregano, savory, thyme), the thymol (essential oil from thyme and ajwain), or even the aromatic aldehydes which can be found in abundance in cinnamon essential oil.

To use a dermocaustic essential oil, it must always be diluted in a so-called carrier or vector vegetable oil and the mixture should only be applied tothe targeted areas.

A photosensitising substance makes the skin ultra-sensitive to solar radiation, resulting in a skin rash in the form of redness. The photosensitising molecules found in certain essential oils are the coumarins.

The following essential oils are not recommended before sun exposure: angelica, bergamot, German chamomile, cinnamon (bark), lemon, sweet fennel, khella, lovage, green mandarin, sweet orange, grapefruit, lemon verbena.