Essential oils have a mighty action on the peripheral nerve endings, relieving the stress and tension that contribute to aging skin and blemishes. Essential oils increase lymphatic flow and the overall condition of the lymph glands, which are important in the health and vitality of the skin. Essential oils also improve circulation, which promotes oxygenation and energizes the skin. Some essential oils can balance sebaceous secretions and act as bactericides, neutralizing or killing unwanted bacteria, thus being a great arsenal in acne treatment.  With anti-inflammatory properties, essential oils can calm reactive skin.

1. Essential oils are often diluted, cut, changed, or mixed with synthetic scents; this process is known as adulteration. If the price seems too good to be true, chances are that the oil has been adultered. Developing a good sense of smell for essential oils will help in separating out those with synthetic additives. True essential oils are complex while synthetics are typically flat. Gas chromatography and mass spectroscopy are two excellent types of tests to ensure the purity of essential oils and that they have not been adultered.

2. There are many different methods of extracting essential oils. One of these methods, steam distillation, is the process that the majority of essential oils are obtained through. The pressure, temperature, and time can vary with each individual essential oil in this process. In this method, plant material and water are heated and droplets of oil are carried through several tubes and receptacles by the steam. After being cooled and warmed, the essential oil is eventually drawn off. Hydrosols are also obtained in this process. Another method, cold press extraction, is primarily used to extract citrus oils. With this method, citrus peels are mixed with a small amount of cool water and then pressed, extracting the oil. Solvent extraction is another process that is used when heat would negatively affect the essential oil, such as delicate flower essential oils. Aromatic plant materials are mixed with a solvent such as ethanol, hexane, benzene, ether, or tetrachloride; these solvents are removed by evaporation. CO2 extraction is a vacuum method with varying pressure at a little over room temperature (33 degrees Celsius). Although the equipment is expensive and small in size, this method is an excellent form of extraction as there is no heat damage and no risk of chemical contamination. Furthermore, the extraction is immediate.

3. Essential oils are obtained from a myriad of plants and from different parts of plants. Vetiver and angelica, for example, are root oils whereas peppermint, eucalyptus, and niouli essential oils come from leaves. Flowers produce delicate oils such jasmine, rose, and neroli oils.  Essential oils are also obtained from seeds, which are usually associated with food, such as fennel, coriander, and anise. Trees and bushes create essential oils in their bark (sandalwood, rosewood, and cedar) and resins (frankincense and myrrh).

4. Any essential oil can be dangerous at high dosages. Lavender, one of the most commonly used essential oils by skin care professionals, can cause adverse reactions in some individuals. Many oils are contraindicated in pregnancy; these oils include cedarwood, citronella, marjoram, white thyme, anjelica, and cinnamon leaf. Additionally, peppermint and rosemary should be avoided in the first trimester.  Certain essential oils should be used in moderation by experienced aromatherapists only; these oils include basil, cedarwood, sage, tuberose, and clove. Others carry high-toxicity risks and, therefore, should be completely avoided; these oils include thuja, mugwort, pennyroyal, rue, and cassia.

5. Rose oil has over 300 constituents. There is absolutely no synthetic rose oil that comes close to the beautiful complexity of true rose oil. It takes about 60,000 roses to produce just one ounce of oil.

6. Essential oils that are known dermal irritants, and, consequently, should not be used in skin care, include white camphor, cedarwood, cajeput, and clove. Though commonly used, peppermint, lemon, and eucalyptus essential oils can also cause skin irritation and should be used with caution. Furthermore, there are essential oils that are phototoxic and should be avoided in skin care (topically); these oils include citrus oils, bergamot, St. John’s wort, ginger, and verbena.

7. Essential oils should always be used with a carrier oil, such as jojoba, safflower, or grapeseed. There are only a few that can be used neat (directly on the skin); these oils include lavender, tea tree, ylang ylang, and sandalwood. However, it is a good idea to use a carrier oil with all essential oils in topical application.

8. Chemical compounds, which are composed of carbon, hydrogen, and oxygen, comprise two groups: hydrocarbons (which include terpenes) and oxygenated compounds (which compose esters, phenols, aldehydes, ketones, and terpene alcohols). A few exceptions aside, the ending of the chemical names of essential oils represent the following: ‘ene’ denotes a terpene (limonene); ‘ol’ denotes an alcohol (linalool); ‘on’ denotes a ketone (thujone); and ‘ole’ represents an oxide (cineol).

9. Essential oils should always be tightly closed, kept in a cool place away from direct sunlight to avoid photo-oxidation, and stored in a dark, glass container.

10. Esters are probably the most common and extensive group of essential oils. Lavender, helychrisum, neroli, Roman chamomile, and petitgrain have a very high content of esters.

Krista McKowen, a licensed aesthetician and instructor with a passion for wellness, has over 34 years of experience in the skin care industry, ranging from spa owner, medical spa director, writer, and educator. She is Director of Media Education for BiON Research. Through a dedication and philosophy of creating beauty through skin health, McKowen has both a clinical and holistic background. Her expert knowledge stems from extensive and ongoing studies in cosmetic chemistry, massage therapy, aromatherapy, thallasotherapy, phytotherapy, health, and nutrition.