The Full Story

Essential oils are derived from plant parts. Because they have a scent, essential oils are often used in homemade and commercial perfumes, cosmetics, and room fresheners. Some are used, in minute amounts, in food preparations. Some are present in pesticides. Many essential oils have a long history of medicinal use, too.

Numerous essential oils are known. A few common ones are camphor, peppermint, wintergreen, sandalwood, sage, lavender, clove, cinnamon, tea tree, eucalyptus, and bergamot.

Many people think essential oils are harmless because they are natural and have been used for a long time. In some cases, that is simply not true. Many essential oils can cause rashes if used on the skin. Many can be poisonous if absorbed through the skin or swallowed. Few have been tested like medicines have, even though people put them in their mouths, on their skin, and in their children’s vaporizers. Aspirating an essential oil can cause pneumonia; this can happen if someone tries to swallow it, but chokes so that a little goes into the lungs.

Individuals can have varying reactions to essential oils, as they might to other medicines and products. For example, anyone can be allergic to anything – whether or not it causes allergic reactions in others. Children, with their thin skin and immature livers, might be more susceptible to toxic effects than adults. There could be interactions with other drugs, too. Depending on how the essential oil is prepared, there could be toxicity from other ingredients; these preparations often contain other oils or alcohol.

Since essential oils generally are not regulated, it can be hard to know exactly what is in the essential oil bottle – what species of plant, what concentration of active ingredient, or whether there are any contaminants.

Here's what is known about a few essential oils.

Peppermint is used for gastrointestinal discomfort. It's important to choose the correct species of mint, as some types are poisonous; for example, pennyroyal oil is very poisonous to the liver.

Wintergreen is used in some over-the-counter skin preparations to relieve pain. It creates a feeling of warmth because it causes blood vessels to enlarge. BUT – a big but – oil of wintergreen is very dangerous if more than a tiny amount is swallowed. Oil of wintergreen is used as a food flavoring in trace amounts, but drinking from the bottle can be deadly. Swallowing oil of wintergreen is like swallowing a large number of adult aspirin.

Tea tree oil is used for some kinds of fungal skin infections.

Nutmeg is used in food but, when misused or abused, can cause hallucinations and coma.

Eucalyptus is used for its soothing effects when inhaled, for example during a cold or cough. If swallowed, eucalyptus oil can cause seizures.

Sage oil has been used as a scent, seasoning, and remedy. Swallowing more than a very small amount has caused seizures in children.

Camphor is used as a moth repellent and as an ingredient in skin preparations. Even a small amount of camphor is dangerous if swallowed. Seizures can begin within only a few minutes. Camphor poisoning also occurred when skin preparations containing camphor were applied repeatedly on children – more frequently than the label recommended and/or covered up with extra clothing.

Safely using and storing essential oils is extremely important.

If an essential oil is found in a cosmetic product, use it according to label directions. Stop using it immediately if a rash or other skin reaction occurs and gently wash it off.

If it's found in a scent, be sure that it is used and stored where children can't find it.

If it's in a medicine, use according to label instructions ONLY.

If, for some reason, you have bottles of essential oils at home, consider discarding them (safely) if you have young children. Otherwise, they MUST be locked up, out of sight and reach of children and pets – all the time.

If someone swallows an essential oil, or a product containing essential oils, use the webPOISONCONTROL® online tool for guidance or call Poison Control at 1-800-222-1222 right away. Poison Control will help you figure out if this could be dangerous and will tell you exactly what to do.

Rose Ann Gould Soloway, RN, BSN, MSEd, DABAT emerita

Clinical Toxicologist

For More Information Essential oils intended for medicinal use (National Center for Complementary and Alternative Medicine of the National Institutes of Health)