French Aromatherapy: Chemistry of Essential Oils (for the non-Chemistry major)

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on February 16, 2016


Chemistry of Essential Oils (for the non-Chemistry major)

I am by no means a Chemistry major.  Chemical formulas and math make my head spin but as I’ve found myself falling more and more in love with the amazing benefits of essential oils I’ve started to wonder how, and why, a few tiny little drops can have such a profound impact on one’s health and well being.  If you’ve paid any attention when ordering your essential oils you’ve probably noticed a couple things: 1) they all have funny Latin names that you can barely pronounce (if they don’t you need to seriously reconsider your supplier) and 2) the descriptions of the oils often reference “constituents” or “compounds” like d-limonene, α-pinene, methol, camphor, etc.  But what does all this actually mean?

What’s in a name?

Can you guess what essential oil Lavandula angustifolia is? If you guessed Lavender, you’re correct! A reputable essential oil company will always list the Latin, or botanical, name of their essential oil because using common names can result in much confusion.  Do you know how many varieties there are of Lavender? There are at least 5 different kinds of Lavender that are common to find in essential oils: Lavandula angustifolia (English Lavender), Lavandula officianalis (French Lavender), Lavandula stoechas (Spanish Lavender), Lavandula latifolia (Spike Lavender), Lavandula x intermedia (Lavandin, a hybrid of Lavender and Spike Lavender).  And while they all sound the same they each have unique chemical makeups and are valuable for different therapeutic properties.  For example, you may have heard that Lavender essential oil is good to use to help soothe burns and promote healing.  And you’d be correct… if you used 100% pure Lavandula angustifolia.  However, pure essential oils take time and cost money to steam distill and many unscrupulous essential oil companies will use a hybrid called Lavandin (Lavandula x intermedia) which is a much cheaper alternative.  But Lavandin has a different chemical makeup than English Lavender and while beneficial for many things, like respiratory support and muscle aches and pains, Lavandin is not as good for your skin and due to different properties (a high camphor content) can actually make some burns worse.

If its been awhile since you’ve taken biology, then all these big long names probably read like Greek (well, Latin actually).  So here’s a breakdown of what these names actually mean:

The Latin binomial (e.g., Lavandula angustifolia) distinguishes a plant from all other plants by listing the genus and species.  The genus (e.g., Lavandula) refers to a group of plants that are all similar in botanical structure.  That’s why all five of the Lavender varieties listed above have the same first name.  The Genus is always italicized and capitalized. The species name (e.g., angustifolia) identifies the exact plant within the genus.  This distinguishes this plant from others based on the specific characteristics of the plant, which may include the leaf or flower structure, reproduction, or other identifiable characteristics.  Species names are always italicized and in lower case.

Some plants are actually hybrids, or cultivars.  Hybrids are plants that have been cross fertilized between two different varieties within a species (e.g., Lavandula x intermedia) whereas cultivars are plants that have been cultivated to have certain desirable characteristics, such as appearance, aroma, or even taste.  Both hybrids and cultivars are designated by the use of a multiplication sign (x) in the Latin name.

And to take this one step further, some plants actually produce different chemotypes.  A chemotype occurs when a specific genus and species of plant produces a chemical in a higher concentration than usual.  This may occur due to changes in geographical location, altitude, weather, pests, plant competition, or other environmental interactions.  A chemotype is not a different genus or species but rather an anomaly in the chemical composition of the plant.

The two most common chemotypes in essential oils are Rosemarinus offficinalis (Rosemary) and Thymus vulgaris (Thyme).  A chemotype is identified by the letters ct. Let’s discuss Rosemary in more detail to help you better understand.  Rosemary has three main chemotypes: camphor, cineole, and verbenone.  Rosemarinus officinalis ct camphor is higher in ketones and helps support the circulatory system and may aid in relief from muscle aches and pains, making it an ideal addition to massage oils and blends.  Rosemarinus officinalis ct 1,8-cineole is higher in oxides and helps support the respiratory system by breaking up mucous and helping to minimize swelling in the lungs and nasal passages.   Whereas Rosemarinus officinalis ct verbenone is high in both ketones and monoterpenes which helps support cell regeneration.  It is less stimulating that the other two varieties making it the best choice for skin and hair benefits.

However, not all essential oils have different chemotypes and not all chemotypes are always available from your essential oil supplier. Unfortunately Young Living does not list chemotypes on their oils.  Some chemotypes are well known, like Rosemary, which is  Rosemarinus officinalis ct 1,8-cineole, which is identified in the Essential Oils Pocket Reference (EOPR) guide published by Life Science Publishing (authored by Young Living’s founder Gary Young).  Others, like Thyme, are not identified.  When I reached out to Young Living to inquire about this it was explained to me that the Seed to Seal guarantee ensures the ideal growing conditions to produce the desired characteristics in the plants which the oils are distilled from.  However, the EOPR identifies the variety of Thyme used to distill Young Living’s Thyme essential oil as “Red Thyme.” Thus, the chemotype of Young Living’s Thyme is actually Thymus vulgaris ct thymol.  So with a little legwork, the chemotypes can still be identified.  I do wish, for the sake of aromatherapy students and those essential oil enthusiasts who are especially interested, that Young Living would consider including this information on their labels however.

Chemical Constituents

So, how do essential oils actually work?  To fully understand where they get their therapeutic and healing properties from you must first have a basic understanding of the underlying chemistry of essential oils.

100% pure essential oils are volatile compounds that are derived through either distillation or cold-pressed expression from plant material.  In this case, volatile means that the chemical compounds will evaporate quickly when exposed to air.  Some unscrupulous companies will use high heat and/or add chemical solvents to speed up this process and thus increase their profit margin which can impact the quantity, and quality, of the therapeutic constituents that come through the distillation or expression process.  That is why it is so important that you choose an essential oil company you can trust!

During the distillation process steam, or water, rises up through the plant material which breaks it down into its chemical constituents.  These volatile compounds rise upwards, as a vapor, through the distillation machine into a condenser which then cools the compounds back into a liquid form.  Here, the essential oils separate from the water and can be collected from the surface of the liquid mixture. During expression, the plant material is pressed between two plates and the juices and compounds are collected with a sponge or other device that is then used to separate the essential oils from the water. Expression, or cold-pressing, is used almost exclusively for citrus oils, but some carrier oils (like olive or coconut oil) are also collected via cold-pressing or expression.

So, what exactly are these volatile compounds in essential oils made of?

In general, the key components of pure essential oils can be broken down into 2 categories of volatile constituents: hydrocarbons and oxygenated compounds. Hydrocarbons are simply organic compounds made entirely of hydrogen and carbon.  These hydrocarbons are made up almost exclusively of terpenes: monoterpenes, sequiterpenes, and diterpenes.  Oxygenated compounds, also called terpenoids, occur when oxygen molecules are added to these hydrocarbon units.  The oxygenated compounds found in essential oils are usually alcohols, esters, aldehydes, ketones, phenols, phenylpropanoids and ethers, oxides, lactones and coumarins.  I will discuss each of these in more detail below.


Before we begin discussing each of these compounds you must first understand that I will be discussing the benefits of these compounds at the cellular level that have been taught to me during my aromatherapy certification classes.  I will also be listing examples of essential oils that are rich in these compounds.  I am NOT implying that the essential oils listed will have the therapeutic uses of the compounds listed, I am merely giving examples.  At a later date I will be discussing many of the essential oils I’m learning about during my aromatherapy certification in their own profile blog posts where we will discuss their uses and how they can support various bodily systems and promote general health and wellness. 


Terpenes are hydrocarbon molecules found in plants that play a role in protecting the plant from pests, pathogens, and competing plants.  There are over 40,000 known terpene compounds.  Terpenes are classified according to the number of isoprene units that their molecules contain.  An isoprene unit is merely a grouping of 5 carbon atoms.  Monoterpenes contain two isoprene units, sequiterpenes contain three isoprene units, and diterpenes contain four isoprene units.

Monoterpenes – “The Mamas”

Monoterpenes are the most abundant of the volatile compounds and are found in nearly all essential oils.   A friend and fellow aromatherapy student, Rosy Crescitelli, calls monoterpenes “the Mamas” because they tend to coordinate, organize, and unify the bodily systems.   Monoterpenes are highly volatile compounds, meaning they evaporate quickly and their aromas are considered “top notes” because they are the first to hit your nose when you smell a plant or essential oil.  Monoterpenes tend to be warming but not “hot,” stimulating but not overwhelming, and general tonics.  At the cellular level, monoterpenes can be antimicrobial (destroys or resists pathogens), antioxidants (help prevent cell damage from free radicals), analgesics (help relieves or reduce pain), expectorants (aids in the removal of phlegm), decongestants (reduces or relieves nasal congestion), dermal/skin penetration enhancers (getting in deep for sore muscles, tendons and ligaments) and are energizing/uplifting.  Monoterpenes help inhibit the accumulation of toxins, especially in the liver and kidneys. Overall, they help provide support to the lymphatic and respiratory systems.  Monoterpenes can have a drying or dehydrating effect on the skin and mucous membranes.

Monoterpenes tend to have names that end in “-ene.”  Examples of common monoterpenes found in essential oils include: d-limonene, mycrene, α-pinene, β-pinene, delta-3-carene, α-terpinene, etc.

Essential oils rich in monoterpenes include: citrus oils, conifers (e.g., black spruce, cedar, cypress, pine, etc.), angelica, black pepper, elemi, fennel, frankincense, juniper berry, myrtle, nutmeg, rosemary, tea tree, thyme, and valerian.

Safety concerns: α-pinene, β-pinene, and delta-3-carene may cause upper respiratory irritation.  Essential oils containing these constituents in high concentrations should only be used with caution with individuals who suffer from asthma or other respiratory conditions with airway resistance.  In addition, monoterpenes in general can be dehydrating to the skin.  It is recommended to avoid use on the face and heavily dilute when using monoterpene rich essential oils in any skincare products.

Sesquiterpenes – “The Grandparents”

Sesquiterpenes are heavier, thicker, and less volatile than monoterpenes and tend to appear towards the end of the distillation process.  Sesquiterpenes commonly occur in roots, resins, and woods and are more aromatic than monoterpenes. They are nicknamed “the Grandparents” because they tend to be wise, responsible chaperones that see a job through to the end.  Sesquiterpenes tend to be more balanced than monoterpenes and can be warming and/or cooling and stimulating and/or relaxing.  At the cellular level, sesquiterpenes can be anti-allergenic (reduces the symptoms of an allergy), anti-inflammatory (reduces inflammation), antiseptic (destroys or prevents the growth of microbes), analgesic, and sedative in nature.  In general, sesquiterpenes stimulate the immune system, support the venous and lymphatic systems, lowers blood pressure, and may stimulate the liver and the pancreas.  They also are commonly referred to as amplifiers, magnifiers, or enhancers because they increase the half-life (how long the therapeutic properties of the essential oil affects the body) of other essential oils.

Like monoterpenes, sesquiterpenes tend to have names that end in “-ene.”  Examples of common sesquiterpenes found in essential oils include: chamazulene, bisabolene, guaiazulene, α-caryophyllene, β-caryophyllene, etc.

Essential oils rich in sesquiterpenes include: black pepper, cedar, German chamomile, clary sage, clove, copaiba, ginger, helichrysum, myrrh, spikenard, patchouli, and vetiver.

Safety concerns: Sesquiterpenes tend to be very gentle with no known safety concerns or contraindications.

Diterpenes – “The Few”

Diterpenes are much thicker and heavier than monoterpenes and sesquiterpenes making it more difficult for them to make it through the distillation process, thus they have earned the nickname “the Few.”  Because of their molecular weight they tend to have similar properties to sesquiterpines.  They are also considered expectorants and laxatives with some anti-fungal and anti-viral properties.  In general diterpenes help support the endocrine system (e.g., hormonal, thyroid, and adrenal support) as well as the liver and kidneys.

Diterpenes also tend to have names that end in “-ene.” Examples are α-camphorene, hishorene and cembrene.

There are only six essential oils in which diterpenes can be found. They are: clary sage (7%), white camphor (1-2%), pine, cistus, jasmine, and cypress (all <1%).

Terpenoids/Oxygenated Compounds – “The Stars”

As mentioned above, terpenoids are oxygenated compounds that occur when oxygen molecules combine with hydrocarbons or terpenes.  Terpenoids that occur in essential oils can be classified as alcohols, esters, aldehydes, ketones, phenols, phenylpropanoids and ethers, oxides, lactones and coumarins.  They are considered “the Stars” because they give the oil it’s characteristics and personality.


Alcohols in essential oils are  compounds that contain a hydroxyl (-OH) attached to one of the terpene groups (monoterpenes, sesquiterpenes, or diterpenes).  Considered to be the most therapeutically beneficial compounds in essential oils.  Alcohol rich essential oils are generally considered to be nontoxic, safe for use with children and the elderly, and often used in skin care products.

Alcohols tend to have names that end in “-ol.”

Monoterpene Alcohols/Monoterpenols – tend to be warming, stimulating, and general tonics.  Monoterpenols are considered to be sedatives, calming to the nervous system, and support the immune system.  At the cellular level monoterpenols can be antifungal, antiviral, and anti-bacterial in nature.  They tend to bring balance and serenity to the individual, reduce stress, and help strengthen the individual’s terrain, making them good for longer treatments and chronic illnesses.

Examples of monoterpenols found in essential oils include: borneol, lavandulol, nerol, citronellol, linalol, terpinen-4-ol, geraniol, menthol, α-terpineol, etc.

Essential oils rich in monoterpenols include: bergamot, basil, citronella, clary sage, coriander, hyssop, lavender, marjoram, melissa, neroli, palmarosa, peppermint, petitgrain, rose, tea tree, thyme, and ylang ylang.

Safety concerns: Menthol rich essential oils (like Peppermint) should not be used internally or on or near the face of infants or small children as it can cause respiratory distress.  In addition, individuals with gastroesophageal reflux or hiatal hernias should be cautioned when using menthol rich essential oils internally as they may decrease esophageal sphincter pressure.  Sensitive individuals may experience heartburn when taking peppermint internally.

Sesquiterpene Alcohols/Sesquiterpenols – tend to be slightly warming, calming yet stimulating, and promote balance.  At the cellular level sesquiterpenols can be anti-inflammatory, antimicrobial, and antifungal.  In addition, they tend to have an estrogenic quality and can act as hormone system regulators as well as provide support for the respiratory, circulatory, and lymphatic systems.

Examples of sesquiterpenols found in essential oils include: α-bisabolol, daucol, α-santalol, β-santalol, carotol, farnesol, cedrol, patchoulol, zingiberol, etc.

Essential oils rich in sesquiterpenols include: carrot seed, cedar, clary sage, German chamomile, patchouli, sandalwood, and valerian.

Diterpene Alcohols/Diterpenols – rarely come through the distillation process.  They have a similar structure to human steroid hormones and tend to have a balancing, harmonizing effect on the endocrine system. The most common diterpenol is sclareol found in clary sage.   At the cellular level, sclareol can be anti-inflammatory and has shown some possibility at being anticarcinogenic in nature (may inhibit the development of cancer).


Esters are the product of chemical reactions between organic acids and alcohols.  Esters are characterized by intensely fruity aromas and are widely used by the perfume industry to create soft, floral fragrances.  They tend to be cooling and relaxing to the nervous system.  Esters regulate, balance and harmonize the individual organism.  At the cellular level, esters are great antispasmodics (relieves smooth/skeletal muscle spasms) and can also be anti-inflammatory, calming, analgesic, anxiolytic (relieves anxiety), and can help regulate cardiac rhythm and can have a hypotensive action (lowers blood pressure). Esters have been found to be helpful in treating depression, anxiety and can help dissolve fears when applied to the solar plexus.

Esters tend to have names that end in “-ate” or “-ester.”  Examples are methyl salicylate, bornyl acetate, geranyl acetate, linalyl acetate, isobutyl angelate, methyl benzoate, lavandulyl acetate, eugenyl acetate, etc.

Essential oils rich in esters include: bergamot, black spruce, Roman chamomile, cardamom, clary sage, coriander, frankincense, laurel, lavender, neroli, petitgrain, valerian, wintergreen, and ylang ylang.

Safety concerns: Methyl salicylate is an aspirin-like compound found in high concentrations in wintergreen essential oil.  Upon ingestion, methyl salicylate converts to salicylic acid. In small doses, salicylic acid is analgesic, fever reducing, and anti-inflammatory however used over time and in high concentrations can cause poisoning.   One tsp (which is the equivalent of drinking a 5 ml bottle) of wintergreen essential oil is approximately 7000 mg of salicylate or the equivalent of 21.7 adult aspirin. Ingestion of as little as 4 ml in a child can be fatal (this is why Young Living has childproof caps on Wintergreen and PanAway essential oils).  Because of its liquid, concentrated form and lipid soluability, methyl salicylate poses the threat of severe, rapid-onset salicylate poisoning and internal usage should be avoided.  Individuals taking blood thinners (e.g., warfarin) or salicylate-based medication should avoid using essential oils containing high concentrations of methyl salicylate.


Aldehydes are closely related to ketones but differ slightly in their chemical structure.  Aldehydes have very powerful aromas, usually slightly fruity, and are widely used in the perfume industry (usually to create synthetic fragrances). Both aldehydes and ketones are used in industrial production as food, fragrance, medical, and agricultural chemicals.  They are perhaps most well known in the food industry to create artificial and/or natural additives to food (e.g., vanillin from vanilla).  Aldehydes tend to be cooling, calming and relaxing to the nervous system, have a sedative effect and can be helpful in reducing temperature.  At the cellular level, aldehydes can be anti-inflammatory, antiseptic when diffused into the air, antifungal, and antiviral.  Aldehydes are known to help support the lymphatic and nervous systems.  They can help calm fears and relieve emotional distress by activating the solar plexus. They are also known aphrodisiacs and may help with sleep related issues.

Aldehydes tend to have names that end in “-al.”  Examples are citronellal, citral, geranial, neral, etc.

Essential oils rich in aldehydes include: cassia, cinnamon bark, citronella, eucalyptus radiata, geranium, ginger, lavender, lemon, lemongrass, lime, melissa, orange and verbena.

Safety notes: Aldehydes oxidize easily and when combined with oxygen can form acids called carboxylic acids which are known skin irritants and sensitizers.   Many aldehydes can be skin and mucous membrane irritants and should be diluted for topical use or as airborne antiseptics.


Ketones are similar to aldehydes in structure but less reactive and not prone to oxidation.  Ketones tend to be cooling, relaxing to the nervous system and are have powerful wound healing properties.  At the cellular level, ketones can be mucolytic (dissolves or breaks down mucous), lipolytic (breaks down fat), antiviral (especially on herpes and neurotropic viruses), and antiparasitic.  In general, ketones can help modulate the immune system in small doses.

Ketones tend to have names that end in “-one,” except for camphor.  Examples are camphor, cryptone, methone, thujone, verbenone, etc.

Essential oils rich in ketones include: dill, fennel, hyssop, peppermint, rosemary, sage, spearmint, and thyme.

Safety notes: Essential oils with high concentrations of camphor should be avoided with infants and small children.  Some ketones may be neurotoxic at high enough doses.  Essential oils with ketone toxicity that present safety concerns are rue, mugwort, wormwood, thuja, pennyroyal, and sage (which should never be ingested).  All of these oils are contraindicated during pregnancy or breastfeeding.  Young Living does not carry any of these oils, except sage.

 Phenols – “The Teenagers”

Phenols, like alcohols, have a hydroxyl (-OH) component.  Unlike alcohols it is attached to the carbon molecule of a benzene, or aromatic, ring.  Phenols are really strong constituents and can stimulate both the nervous and immune system.  In French aromatherapy, these compounds are understood to help support healthy intestinal flora.  However, they’ve earned the nickname “the Teenagers” because they can be irritating, especially to the skin and mucous membranes.  Phenols tend to be warming (“hot” oils), stimulating and act as general tonics.  At the cellular level phenols can be antibacterial, anti-inflammatory, antiviral, antifungal, and airborne microbials. In general, phenols can help support the respiratory and digestive systems in addition to being immunostimulants.

Like alcohols, phenols tend to have names that end in “-ol.”  There are only 3 main phenols commonly found within essential oils: carvacrol, thymol, and eugenol.

Essential oils rich in phenols include: oregeno, mountain savory, marjoram, thyme, and clove

Safety notes: In general, phenols tend to be irritating to the skin and mucous membranes therefor any essential oils rich in phenols should only be used diluted with a carrier, for both internal and topical use. Internal use of carvacrol rich essential oils should be avoided in those on medication to manage blood glucose for diabetes.  Eugenol may contribute to liver toxicity and long-term use should be avoided.  In general individuals on anticoagulant drugs or with bleeding disorders should only use essential oils rich in phenols with caution.

Phenylpropanoids & Ethers

Phenylpropanoid compounds are rare in essential oils but noteworthy because they have strong antimicrobial action  and pleasing aromas and flavors.   Phenylpropanoids tend to be warming, stimulating and tonic in action.  At the cellular level, phenylpropanoids can be analgesic, antispasmodic, antibacterial, antimicrobial, and antihistamine in nature.  In general, they help support the immune system.

Phenylpropanoids tend to have names that end in “-ole” or “-ol,” with the exception of cinnamic aldehyde.  They can be separated into two main groups, the phenylpropanoids, which include cinnamic aldehyde and eugenol, and the ethers, which include anethole, methyl chavicol (estragole), and methyl eugenol.

Essential oils rich in phenylpropanoids include: fennel, basil, cinnamon bark, Laurus nobilis (also known as bay laurel), myrtle, clary sage, and melissa.

Safety notes: Internal consumption of cinnamic aldehyde should only be used with caution in individuals taking medications to control blood glucose for diabetes.  Eugenol can be irritating to those with sensitive skin and oral use is cautioned in those taking MAOIs, SSRI.s, pethidine, and indirect symnpathomimetics.  Use of both cinnamic aldehyde and eugenol is cautioned in individuals on anticoagulant medication or with bleeding disorders.  Methyl eugenol can contribute to liver toxicity through prolonged use.  Newborns are at a higher risk to the effects of methyl eugenol than adults, therefore use of essential oils high in methyl eugenol should be avoided with newborns and small children.


Oxides are some of the strongest aromatic compounds found in essential oils. The main oxide compound found in essential oils is 1,8-cineole (also known as eucalyptol) which of often referred to as “the respiratory tract’s best friend” because of it’s ability to act as an expectorant and decongestant at the cellular level. Other potential benefits of oxides include analgesic, anti-inflammatory, antiviral, and antiparasitic properties.

Oxides tend to have names that end in “-ole” or “-oxide.”  Examples of oxides include bisabolol oxide A, bisabolol oxide B, rose oxide and sclareol oxide.

Essential oils rich in oxides include: eucalyptus, tea tree, Laurus nobilis, rosmary, German chamomile, rose, and clary sage.

Safety notes: There has been great debate over the safety of eucalyptus essential oil with children and there are a lot of blogs and online sources that say you should never use it with children under 6, or 10, years old.  The debate stems from concerns that 1,8-cineole can interfere with respiration in infants and small children when used throughinstillation (which means direct introduction of the essential oil into the nose through the use of an atomizer, inhaler or drops).  Using essential oils rich in 1,8-cineole on or near the face of infants and small children is not recommended.  However, this does not mean that you should never use eucalpytus, or other 1,8-cineole rich oils, with your children.  Used cautiously and diluted on the VitaFlex points on the feet or diffused these oils can be used safely.

Lactones & Coumarins

Last but not least are the lactones and coumarins.  Lactones are a special kind of ester and tend to be found in expressed (e.g., citrus) or absolute (e.g., jasmine) oils but can also be found in small quantities in many other essential oils.  Lactones will never be the principle constituent in any oil but their strong properties will enhance the therapeutic effects of the oils they can be found in. They tend to have similar therapeutic properties to ketones and can act as decongestant and expectorant at the cellular level and help support the liver and immune system.  Examples of lactones include aesculetine (peppermint), bergaptene (fennel), bergamottin (lemon), butanolide (lavender), citropten (petitgrain), furanogermacrene (myrrh), herniarin (German chamomile), limettine (lime), psoralen (bergamot), and scopoletin (Roman chamomile).  There’s a specific kind of sesquiterpene lactone, called helenalin, that is found primarily in arnica oil and accounts for it’s renowned anti-inflammatory effects.

Coumarins, are a special kind of lactone which tend to have a grassy, “green” smell (like freshly cut grass or alfalfa hay) and are also reponsible for the flavor and aroma of coconut.  Coumarins have strong therapeutic properties and tend to be calming to the nervous system and help support the immune system. At the cellular level they can be great antispasmodics and anticonvulsants which can be helpful in those with nervous tics and disorders.

Safety notes: Furanocoumarins are a coumarin derivative that tend to be photosensitizers, meaning they can result in sunburn or serious blistering when exposed to UV light.  Furanocoumarin examples include angelicin, found in angelica essential oil, and bergapten, found in expressed citrus oils like bergamot, lime, lemon, grapefruit, and tangerine.

So, there you have it.  A crash course in the chemistry of essential oils in laymen’s terms.  Hopefully I did a good job explaining these concepts in terms that anyone can understand.  This should help lay the foundation as I move forward with my French Aromatherapy blog series and start introducing specific oil profiles. Keep in mind as I mentioned in my disclaimer above that just because I’ve listed examples of essential oils rich in these chemical constituents does NOT meant that these oils will affect an individual in these ways at the cellular level.  I will be discussing how specific essential oils help support various bodily systems  and can be used to promote general health and wellness in future blog pots. 

Questions or comments? I’d love to hear them!


  • Reference material provided by East-West School for Herbal and Aromatic Studies as part of their French Aromatherapy certification class
  • Rosy Garcia Crescitelli, a fellow aromatherapy student.  You can follow her on Periscope @Rosy_Cresy or on Vimeo. She is attending the Institute of Spiritual Healing for her certificate in clinical aromatherapy (as well as getting her French Aromatherapy certification from the same program I am) and some of the “nicknames” I listed are coined by her ISH instructors Barbara Salange and Linda Smith.  If you are looking for a trusted aromatherapy education that approaches the healing power of essential oils from a Christian perspective you may want to look into this program.  As I understand it, however, this program does not subscribe to the French model of aromatherapy (ingestion).
  • Chemistry of Essential Oils Made Simple by David Stewart – excerpts available online through Google Books 
  • More information on distillation and expression methods and processes from the National Association for Holistic Aromatherapy

Note: These statements have not been evaluated by the FDA. I am an aromatherapy student but I am not a medical doctor.  Products and techniques mentioned here are to help support your specific areas of concern and are not intended to diagnose, treat, cure or prevent any disease. Information here is in no way intended to replace proper medical help. Consult with the health authorities of your choice for treatment.

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