Essential Skin Care: An Introduction by Lynda Sorenson

0.5% or less, depending on the skin to be treated and the oil used. For use in cosmetics on a daily basis, the percentage levels should be reduced even further, depending on the Essential oil in question, to 0.15% or less. I will address those variations as I discuss them. It is my experience that the beneficial effects of using the oils are just as great if not greater at these concentrations than in higher concentrations, and certainly the risks are less.

It is advisable to perform a skin patch test before using any new Essential oil or blend. This can be done either by applying a minute amount of the Essential oil to the inside of the elbow, and waiting for five minutes to observe any reaction. Or by applying the properly diluted blend to the same area, covering it with clear tape, and reading the area for sensitization after 24 hours. Some indications of adverse reactions to the Essential oil or oils may include redness, irritation, itching, inflammation, hives or scaliness. In such cases the substance tested should not be used on this person. Indeed, when one considers that anyone can develop an allergy to anything at any time - regardless of the duration of previous, safe use - and that using a substance on the skin for a long period of time albeit safely can actually increase the risk of eventual adverse reaction, it can be advisable to occasionally re-perform a skin patch test with the Essential oil or blend in question.

Here, from �Plant Aromatics�, is a list of Essential oils that should not be used on the skin. Bear in mind that no such list could cover all possibilities as each person has unique potential for sensitivity to a variety of substances. Alant Root (Inula), Bitter Almond, expressed Bergamot, Sweet Birch and Birch tar oil, Boldo leaf, Cade, Calamus, Camphor, Cassia, Cinnamon Bark, Colophony, Costus root, Fig leaf absolute, Horseradish, Mustard, Opoponax, Peru Balsam, Rue, Sassafras, Tansy, Terebinth, Tolu balsam, Turpentine, Verbena and Wintergreen.

It is also important to consider the possibility of photosensitization when using Essential oils on the skin. This results when a substance applied to the skin induces an adverse reaction when the skin is subsequently exposed to sunlight or strong ultraviolet light. The reaction can range anywhere from redness and irritation, to changes in pigmentation, to burns, and result in a permanent sensitization to the oil. Factors that increase the photosensitizing effects are an increase in altitude, and increases in humidity and heat. Again from �Plant Aromatics�, a list of photosensitizing oils: Angelica root, expressed Bergamot, Caraway, Cassia, Cedarwood, Cinnamon Bark, Cumin, Dill weed, Ginger, Grapefruit, Honeysuckle absolute, Lavender absolute, Laurel leaf absolute, expressed Lime, Mandarin, Expressed Orange, Patchouli, Rue, and Verbena.

Regarding potential sensitization to Essential oils, I have what I call the �Russian Roulette� theory. Assume that we all have the potential for sensitization to a given oil, say Lavender. For you, that threshold might be crossed after you have used 10 gallons of Lavender Essential oil over the course of a lifetime. So the likelihood of you crossing that threshold in normal life using Aromatherapy on yourself or others is not overwhelming. I, on the other hand, might have a much lower threshold, and react with skin irritation and sensitization at 10 gtt. The unfortunate thing is that neither of us are going to know where our threshold is until we have already crossed it, and at that point it is too late. The harm has been done and we are seriously limited in how we might use that particular oil - if we are able to use it at all - and we run a risk of having similar reactions to other Essential oils or other substances containing the same chemical component that we have developed our sensitivity to in Lavender. This is not to say that you should be frightened of using Aromatherapy at all. Just have respect for the power and concentration of the oils with regard to sensitization, and the chances are greatly reduced that you will ever have problems. Be aware of the signs of sensitization mentioned above, and keep an eye out for them.

As mentioned before, I find �Plant Aromatics� to be an excellent reference on safety issues when using Aromatherapy on the skin. If you intend to practice this on yourself or others either professionally or privately, you would be well advised to get a copy of this book, as it is able to cover the topics of skin irritation, skin sensitization, photosensitization, toxicity and other safety issues with a depth that is not possible in this context.