Joined: 13 Dec 2006
Location: Cleveland, OH
|Posted: Dec Sat 16, 2006 11:17 am Post subject: E.O. - Absorption
|E.O. - Absorption
I thought this was interesting written by an RN, this is excerpt from her article for the Herbalgram
Absorption of Essential Oil Components Through the Skin
by Jane Buckle, Ph.D., R.N
Jager et al11 showed that linalyl acetate and linalol, two components in essential oil of English lavender (Lavandula angustifolia Mill., Lamiaceae), were absorbed from a 2 percent dilution of English lavender in peanut oil through the abdominal skin of human subjects "within minutes" and detected in the blood plasma (ca. 10 ng/ml). The maximum level was attained at 20 minutes; even at 90 minutes, the two components could still be detected.
Fuchs et al12 demonstrated that (R)-(-)- carvone easily penetrated the skin of human subjects, producing a plasma concentration of 24—32 ng/ml after almost 30 minutes. Covering the skin produced a significantly higher effect. Twenty-five percent (R)-(-)- carvone in peanut oil was used. (R) carvone is an isomeric ketone found in caraway (Carum carvi L., Apiaceae). (L) carvone is found in spearmint (Mentha spicata L., Lamiaceae).
Wyers and Brodbeck13 demonstrated that 1,8 cineole was absorbed through the skin into the muscles. They found that when an applicator was used the absorption rate increased 320 percent.
In an email in June 2002, Buchbauer, who led much of the experimental work on topical absorption at the Institute of Pharmaceutical Chemistry, University of Vienna in Austria from the 1980s, is very clear, "It is now common knowledge that fragrance compounds are absorbed through the skin into the blood stream."
Maury, an Austrian nurse who worked as a medical assistant to a surgeon in Alsace, France, prior to World War II, was instrumental in transporting aromatherapy to the United Kingdom in the 1960s.14 Maury researched how essential oils affect the skin in such conditions as psoriasis. She stated that she introduced her ideas to the beauty industry in England (rather than nursing) as she thought that beauticians would be more interested in topical applications of essential oils. She and her student, Daniele Ryman, also viewed essential oils as drugs that should not be administered orally without a prescription. As a result, oral applications were not introduced into England with the topical and inhaled methods used at this time. Since then, aromatherapy has become synonymous with massage (i.e., topical applications) and this association continues today in the United Kingdom. The concentration of essential oils used by nurses in massage is also quite low — typically 1—3 percent solutions of essential oils in cold-pressed carrier oil. Only during the last five years, since 1998, has oral use of essential oils (sometimes called aromatology, a term used with different connotations, depending on who is using it) arrived in England. The Royal College of Nursing insurance policy, which insures nurses, does not cover oral use. In France some physicians use essential oils orally. Aromatherapy massage is not carried out by French nurses.
However, because of its name, many people continue to think that aromatherapy is only about smelling something. That is incorrect. The usual definition is, "Aromatherapy is the use of essential oils for therapeutic purposes."15 No methods are suggested. But, clearly, only essential oils are used. If this definition were accepted, this would exclude synthetics and solvent-extracted absolutes that are obtained by petrochemical extraction. Expressed oils are the only exception that appears to be accepted by the aromatherapy world. Expressed oils are only obtained from the peel of citrus fruit (e.g., lime [Citrus x aurantifolia (Christm.) Swingle, Rutaceae], lemon [C. x limon (L.) Osbeck] and grapefruit [C. x paradisi Macfad.]. Most aromatherapists do not think that carbon dioxide-extracted oils are essential oils, as they have not been obtained by distillation. The argument against anything other than distillation appears to rest on method (heat) and potential impurities from petrochemical solvents. However, a carbon dioxide-extract would contain no impurities, although the chemistry would be different. -Darcy