Toxicity of Essential Oils

Essential oils are very concentrated and should be used with care. Side effects are primarily from overdoses or incorrect useage. Most of them should not be used full strength on the skin and the mucus membranes are particularly sensitive. The recommendation for oral use is that they only be used in this manner under the guidance of a practitioner. Babies, young children, the elderly, pregnant women and those with epilepsy are especially vulnerable and particular care should be used with them.

The general rule of thumb is not to use oils for a prolonged time; take breaks from their usage. Alternate formulas, using one for a few weeks, and then another. It is possible for an oil used for a prolonged time to build up residue in the body and then result in negative effects.

Overexposure to essential oils, through the skin or inhalation can result in nausea, dizziness, headache or a light-headed feeling. If you experience any of these, fresh air can help you recover.

Some effects you may see:

• Allergic reactions are not uncommon with essential oils. Nausea, dizziness, sweating, palpitations, stomach pains and mucous membrane irritation are possible symptoms. If any of these are experienced, stop using the essential oil and the reactions will cease.
• Skin sensitization reaction, such as dermatitis is possible when applied to the skin, even if the essential oil is diluted. Sometimes even the vapors can cause a reaction. The most common problems are with basil, cinnamon, lemon, lemongrass, melissa, peppermint, thyme and tea tree.
• Phototoxic reactions can occur with some essential oils. Photosensitization, causing redness and trauma to the skin on contact with sunlight are most common with bergamot, lemon, lime, orange and other citrus oil.
• Essential oils containing thujone or apiol can be abortifacient. They can cause an accumulation of blood in the pelvic-uterus area and liver damage. These oils include hyssop, mugwort, parsley, pennyroyal, sage and thuja. Other oils to avoid when pregnant are basil, camphor, clary sage, cedarwood, juniper, marjoram, myrrh, rue, tansy and wormwood.
• High doses of some oils, especially those containing thujone and apiol can have narcotic effects. These can have analgesic or paralyzing effects.
• Essential oils that are excreted through the kidneys, such as juniper and sandalwood, can be nephrotoxic. They should not be used over four weeks at a time.

Essential oil of hyssop, rosemary, sage and thyme should be used with caution if you have high blood pressure.

Epileptic attack could be triggered with fennel, hyssop, rosemary, sage and wormwood.

If you experience a strong burning of the skin upon application of essential oil, or get some into your eye, you should dilute with straight vegetable oil, not water.