“There is no such thing as zero risk in this world, but by following the guidelines, we reduce the risk to an absolute minimum.”
Robert Tisserand, author of Essential Oil Safety

Essential Oil Safety

Essential Oil Safety | Aroma Hut InstituteThe vast majority of all commercially available essential oils are completely safe to use for most individuals as long as guidelines for their proper use are observed. Essential oils contain highly concentrated compounds derived from plants and botanicals, some of which may cause allergic reactions or cause severe skin irritation. That said, there is little chance of any serious or lasting harm if instructions are followed. Whether for personal use in the home or a clinical setting, it is critical to read cautions for each essential oil product you intend to use. Follow all dilution protocols and safety recommendations closely for best results.


What can influence the safety of essential oils?


  1. Quality and Purity

It cannot be stressed enough that the purity of the essential oils to be used is paramount when it comes to safety considerations. Adulterated oils, in other words, essential oils that have been blended with substances that are other than what they claim to be, can compound the potential risk of adverse reactions. Adulteration, a term frequently used in debates about one company’s brand of oils being superior to another, is defined as “any practice that through intent or neglect, results in a variation of strength and/or purity.” To learn more about how to determine an essential oils’ quality, please click here to find out more.


  1. Natural Chemical Composition

Some oils contain naturally high levels of aldehydes and phenols, both compounds that can cause adverse reactions. Though all essential oils should be diluted to a safe concentration before being applied directly to the skin, products that are high in phenols or aldehydes should be used with even greater caution as they can be highly irritating. Products high in aldehydes include citronella and citral, which can sometimes be found in oils like melissa, lemongrass, mandarin and lemon. Phenols are responsible for the scent of essential oils and can cause burning or corrosion of the skin when applied undiluted. Essential oils high in phenols include eucalyptus, rosemary, cinnamon, clove, thyme, oregano and savory. Oils that contain either of these components should always be well diluted prior to topical application. Dilution rates vary and are usually between 3-5%, enough to eliminate any possibility of irritation.


  1. Using Essential Oils Safely aka the Method of Delivery

There are three ways to use essential oils: either diffused or inhaled directly, applied topically or taken internally. Each method of delivery comes with its own set of caveats and safety considerations.


Inhalation, whether directly, vaporized or by diffusion, represents a very low-risk factor for most individuals. Even in close quarters, the concentration levels will rarely reach a point where they pose a serious threat. A case could be made to avoid prolonged exposure to highly concentrated levels of any essential oil vaporized continuously into a closed space for an hour or more, in which case the individual may experience nausea, headaches, and other adverse effects.


If ingested internally, consider that essential oils are concentrated thousands of times over from the raw material. For instance, it may take more than a ton of oregano to make one pound of essential oil, so consuming unnaturally large amounts of it would probably not be a good idea. While several essential oils may be listed as GRAS, most essential oils are not safe for internal use, and those that are should be used only with extreme caution. Ingestion should be restricted to acute cases only, much like pharmaceutical preparations and only ingested under the supervised guidance of a qualified practitioner. There simply isn’t a one-size-fits-all when it comes to a maximum dosage of a particular oil with so many other considerations that must be factored in such as a person’s general health, age, possible drug interaction with prescribed medication and duration of use. Many essential oils that boast antibacterial, antifungal and antioxidant properties, could cause an imbalance in someone’s gut bacteria and could potentially cause great harm if misused or overused in this way. Several organizations including the Alliance of International Aromatherapists (AIA) and the National Association for Holistic Aromatherapy have clear guidelines regarding the internal use of essential oils and believe that the use of undiluted or internal use of essential oils should only be advised by a trained aromatherapist with an appropriate level of education including chemistry, basic physiology and anatomy, consultation practices including diagnostics, and formulation techniques and safety practices regarding each specific internal route (oral, vaginal, or rectal). Please visit AIA’s website https://www.alliance-aromatherapists.org/safety-statement for more information.


If using topically, either in a skin preparation, massage oil or for any other reason, the essential oil should be diluted sufficiently to reduce the risk of irritation. A 3-5% solution translates roughly to 3-5 drops per teaspoon (5ml) of carrier oil. Different guidelines apply when using on children, babies or pregnant women. Never use an essential oil full strength on the skin, and test dilutions on a small area, if possible, to ensure safety. Some oils are phototoxic, making skin more sensitive to UV light and potentially leading to blisters, burns, and discoloration with even moderate exposure to the sun. Phototoxic oils include all citrus oils: grapefruit, lemon, orange, bergamot, and lime. Some methods of distillation can reduce the phototoxic nature of these oils, but the user should always err on the side of caution, no matter what the claims.


  1. Strength and Concentration of the Diluted Oil

Dilution factors for most essential oils are between 1% and 5%. At this strength, there are relatively few safety concerns. The more concentrated the blend becomes, the greater the potential for an adverse reaction. Essential oils are lipophilic in nature, meaning that they are fat soluble and so stored in the body for a period of time, presenting greater potential for irritation. Other factors that should be considered include the area of the skin to be treated as well as the client’s personal sensitivities or intolerances.


  1. Skin quality

If the skin is damaged in any way, infected or inflamed, it may be more susceptible to irritation. It is not recommended to use essential oils on damaged or broken skin, as the skin may absorb far more than would be safe even under ‘normal’ circumstances. Adverse reactions are more likely to occur, and the skin condition may become worse. Use extreme caution with clients who are observed to have damaged skin.


  1. Age of the Individual

For use on children and babies, the concentrations should be reduced accordingly. Children have a heightened sensitivity to essential oils, and some should be avoided entirely. There are several essential oils that are not safe for babies. These include wintergreen, peppermint, rosemary, eucalyptus and birch. The aging skin may also be more sensitive to essential oils, so greater dilution factors should be considered in their case as well.



In addition to the above-mentioned considerations concerning essential oil safety, the following general guidelines should bear in mind:


  • Avoid the application of essential oils on allergic or inflamed skin
  • Avoid undiluted application
  • Avoid application to open wounds or otherwise damaged skin
  • Dilute appropriately into carrier oil before applying
  • Perform skin patch tests, especially if sensitivity is already known