The main thing about essential oils is that they are extremely concentrated plant essences, a.k.a. chemicals. Some of them are skin irritants, mucous-membrane irritants (try accidentally rubbing your nose with cinnamon EO sometime – you wouldn’t wish it on your worst enemy), photo-sensitizing (many of the citruses can cause reactions in the sun), or even toxic (hello, absinthe).
Robert Tisserand is the guru for essential oil safety, but his classic safety reference is massive and geared more towards professional aromatherapy practitioners. For the lay person, Kathi Keville’s and Mindy Green’s Aromatherapy: A Complete Guide to the Healing Art has a very helpful chapter that covers the safety basics, and Julia Lawless’s The Illustrated Encyclopedia of Essential Oils has wonderful information for each individual plant. The info below is mostly taken from Keville’s and Green’s book.
General Rules of Thumb
- Use high-quality, pure oils. There is an incredible amount of poor-quality stuff out there. Choose your suppliers with care.
- Do not use oils “neat,” or undiluted on the skin. There are two exceptions to this rule – lavender and tea tree oil, for very specific spot-applications.
- Safe aromatherapy dilution is 2%. This is 10-12 drops EO / 1 oz carrier oil. (Most perfume dilutions are higher, a natural perfume might be closer to 10%, but application typically involves smaller surface area of skin.)
- Keep away from eyes and mucous membranes. Ever touched your eyes after chopping a jalapeno? Yep, that was an essential oil.
- Test for sensitivity. Even diluted, some oils can a reaction. If in doubt, try a patch test in the crook of your elbow at 2% dilution (10-12 drops EO / 1 oz carrier oil).
- Understand photosensitivity. Many citruses naturally contain the chemical bergapten and can cause a reaction to the sun. Good suppliers have warnings for these oils. It’s no big deal if you’re using a tiny amount in a perfume, but you might think twice before using in a lip balm. You can also buy “bergapten-free” oils, which eliminates the problem.
- Do not take orally. Seriously, this is a great way to burn your mouth. That said, you can use them to cook with, if you know what you are doing. Herbs have essential oils too, just much less concentrated. So, when added to recipes in the right amounts, essential oils are dilute and harmless. Keville and Green’s book has some fun suggestions.
- Keep out of reach of young children. Some oils smell sweet and delicious. Little people may want to drink them.
- Be careful when using with children, pregnant women, the elderly, and people with severe or chronic illness. They are more sensitive, so smaller dosage / milder dilutions are required. Use a 1/2% (2-3 drops / 1 oz carrier oil) to 1% dilution (5-6 drops / 1 oz carrier oil). Also, some essential oils are contra-indicated for certain conditions, including pregnancy, diabetes, high blood pressure, etc. So read up on each essential oil before use.
Guidelines for Use with Children
- Safest essential oils for children: lavender, tangerine, mandarin, neroli, frankincense, peititgrain, and Roman Chamomile.
- Use 1/4 to 1/2 the adult dosage. This is 1/2% (2-3 drops / 1 oz carrier oil) to 1% dilution (5-6 drops / 1 oz carrier oil).
Guidelines for Use with Pregnancy
- Safest essential oils for pregnant women: rose, neroli, lavender, ylang ylang, chamomile, citrus (bergamot, grapefruit, lemon, lime, mandarin, orange, petitgrain, tangerine), geranium, sandalwood, spearmint, frankincense.
- Many sources disagree on what’s safe. When in doubt, pregnant women should “follow their nose” – if something smells unpleasant during pregnancy when senses are heightened, then it’s best to avoid it.
- Use a 1/2% (2-3 drops / 1 oz carrier oil) to 1% dilution (5-6 drops / 1 oz carrier oil).