A Quick Guide to Essential Oils and Essential Oil Safety€¦ · Yes essential oils do come from nature, but it is important to understand that they are very concentrated, complex

A Quick Guide to

Essential Oils and

Essential Oil Safety

by Beverley Hawkins

A Quick Guide to Essential Oils and Essential Oil Safety

© Beverley Hawkins


© Beverley Hawkins

Essential Oils – What should you really know about them? ......................................................................... 4

Industries Using Essential Oils .................................................................................................................. 7

Serious Reference Books........................................................................................................................... 9

Reference sites ........................................................................................................................................ 10

Selling to the general public with a health claim .................................................................................... 10

Aromatherapist, what is your scope of practice? ....................................................................................... 11

Administration of Essential Oils .................................................................................................................. 13

Methods of Application .............................................................................................................................. 14

Inhalation ................................................................................................................................................ 14

Topical Dermal Application ..................................................................................................................... 14

Internal Application ................................................................................................................................ 15

Distribution, Metabolism, Excretion ....................................................................................................... 16

Internal Use ................................................................................................................................................. 17

Oral Use of Essential Oils ........................................................................................................................ 19

Should essential oils be used neat or in high percentage dilutions? .......................................................... 21

Skin Sensitization .................................................................................................................................... 23

Misconceptions about Reactions to Essential Oils ................................................................................. 25

Phototoxicity ........................................................................................................................................... 27

Interactions between essential oils and coumadin (warfarin) and other considerations. ......................... 30

Adverse Reactions to Essential Oils ............................................................................................................ 32

Poison Centres in Canada ....................................................................................................................... 32

Poison Centres in the USA ...................................................................................................................... 32

Poison Centres Elsewhere ....................................................................................................................... 32


© Beverley Hawkins

Essential Oils – What should you really know about them?

Over the last few years, aromatherapy and the use of essential oils has had a real surge in popularity and

there has been a large increase in the number of people using essential oils regularly for all sorts of

things.

A simple Google search will bring up lots of sites and blogs that share information on essential oils and

how they should be used. Some are very good, but many are not so good. In addition to this, the

number of groups dedicated to aromatherapy and the use of essential oils on social media sites, like

Facebook, is also growing in leaps and bounds and all of them are sharing information about the oils and

how they should be used.

We live in a very fast paced world these days where many of us are dealing with information overload,

and since you have been told that essential oils are safe to use because they come from nature, you

might think that having access to free, quick, off the cuff recommendations for the use of essential oils

for all sorts of purposes, even serious health conditions, is a time saving way to go. Unfortunately it just

isn’t that simple. Yes essential oils do come from nature, but it is important to understand that they are

very concentrated, complex chemical compounds, and to keep in mind that people can be quite

individualistic as to how they react and respond when exposed to essential oils. It can never simply be a

case of ‘one size fits all’, or ‘it worked for me so it has to work for you’. There is just so much more to

consider. Which is why I believe it is really important for you to know where you are getting your

information and recommendations from. What training does the person giving you the advice and

recommendations actually have? Are they really sharing information or is it marketing rhetoric and

hype? Only you can discern this but I think you owe it to yourself and your precious family to make

sure.

What are Essential Oils? More than 250,000 different plants have been identified to date. Not all of these contain essential oils,

those that do are classified as aromatic plants. Not all aromatic plants contain enough essential oil to

make their extraction commercially viable and today there are around 450 plants that are used to

produce commercially viable essential oils.

When we look at all plants we find that they all undergo primary and secondary metabolism processes.

While the distinction is not always clear, processes generally classified as primary metabolism are those

that have remained relatively unchanged throughout biological evolution. On the other hand processes

belonging to secondary metabolism is according, to Kurt Schnaubelt in Biology of Essential Oils, “…

mostly expendable for the growth and development of the individual plant, yet the plant will not be able

to survive or propagate without it. “

It has been estimated that within the plant kingdom there are somewhere between 50,000 to 100,000

secondary compounds, of which only a small proportion has been identified. Essential oils are the

result of secondary metabolism and are produced in order to meet certain needs and requirements of

that particular plant. Exactly why essential oils evolve into such complex chemical compounds is

unclear. However, the fact that variable factors such as, time of day, time of year, maturity of the plant


© Beverley Hawkins

and others can cause changes in the plant’s essential oil complex chemistry indicates that the plant

adapts and changes the essential oil it produces to meet its needs and requirements at the time.

What is the function of essential oils in plants? Research indicates that essential oils appear to fulfill two main functions in the plant. Those of

communication and defence.

Once formed in the plant, essential oils are stored in special structures, such as secretory hairs,

secretory cells within the epidermis, special sacs made from several secretory cells surrounding an oil-

filled space and secretory ducts (tubes lined with secretory cells). Where the essential oil is stored can

sometimes be an indication of its function. For instance when essential oils are stored in secretory hairs

(which point outwards from the surface of the leaves and stems of the plant) if something brushes up

against the plant, the essential oil is quickly released into the air, perhaps an indication that it is there to

repel predators. On the other hand when the essential oil is stored in secretory sacs and ducts (mostly

located inside the leaves, heartwood or roots of the plant) the function appears to be one of protecting

the plant against bacteria, fungi and pests. While not the only component of a plant to attract

pollinators, the fact that some essential oil components are to be found in the essential oil at times that

appropriate pollinators are likely to be around, appear to indicate that the essential oil also plays a role

in the success of pollination.

How is the essential oil extracted from the plant? Purists will tell you that end products obtained after

subjecting plant material to a steam-distillation, a hydro-

distillation, or a combination steam-hydro-distillation,

the , hydro, steam/hydro distillation are essential oils

and hydrosols also known as hydrolates. Other methods

used to obtain these highly aromatic extracts are:

Expression, also known as cold pressing used specifically

with citrus fruits; Enfleurage previously used for delicate

flowers, not used very much today; Solvent Extraction

and CO2 hypercritical extraction.

How much essential oil there is available to be extracted from any plant will vary depending on the

particular plant. To get an idea of just how concentrated our little bottles of essential oil actually are, I

would ask you to consider the following figures showing the percentage yield of essential oil obtained

from a selection of plants. For instance:

Peppermint yields about 0.3 – 0.4% volatile oil Spearmint yields about 0.7% volatile oil

Sweet Marjoram yields about 0.2 – 0.8% volatile oil Rosemary yields about 0.5% volatile oil

Rose yields about 0.02 – 0.03% volatile oil Petitgrain yields about 0.2% volatile oil


© Beverley Hawkins

So what does this really mean? It means that in order to produce 30 ml or 1

ounce bottle of peppermint essential oil (yield of 0.3%) you would have to

steam-distil around 10 kg (over 20 lbs) of Peppermint flowering tops. And if

you wanted to produce a 30ml 1 ounce bottle of rose essential oil (yield

0.02%) you would need to steam-distill around 150 kg (330 lbs) of rose petals.

Understanding that essential oils are formed as secondary metabolites in

plants, as well as gaining a new perspective of just how much plant material it takes to make just a little

bit of essential oil, can certainly give one new insight into just how important it is that when using

essential oils, you do so with knowledge and respect, following safety guidelines and appropriate

protocols.


© Beverley Hawkins

Industries Using Essential Oils

While Aromatherapy is becoming more and more popular, the amount of essential oils used by the

whole Aromatherapy Industry is very small. Essential oils are widely used across the Food, Drugs and

Cosmetics (including Perfumery) Industries and this is where the bulk of the essential oils produced

today still end up.

The cosmetic industry has conducted the majority of research on the safety of using essential oils, and

their chemical components on the skin. This has resulted in the implementation of maximum use levels

recommendations of essential oils used in cosmetics and perfumes. There is usually a difference in the

percentages considered safe in cosmetics and those considered safe in perfumes.

The food industry uses essential oils for flavouring and the research done by this industry has resulted in

the implementation of Highest Maximum Use Levels of essential oils for this industry, which may vary a

bit depending on which food product the oils might be added to, however these recommendations are

always in parts per million.

The Pharmacological Industry has conducted research on the possible pharmacological activities of

different essential oils and/or one or more of their components.

Proper Scientific Research is expensive and is usually only conducted by large companies or institutes

which explains why there is not much research funded purely by the Aromatherapy Industry. Research

is generally only viable when there is some sort of a commercial reward at the end of the process.

According to Ernest Guenther in Volume I of The Essential Oils (6 volume set) essential oils are actually

used in lots of industries such as:

Adhesives: glues, paper and industrial tapes, pastes, Porcelain cements, rubber cements, scotch tapes,

etc.

Animal Feed Industry: Cat foods, dog foods, cattle feeds etc.

Automobile Industry: Automobile finishing supplies, polishes, cleaners, soaps, etc.

Baked Goods Industry: Biscuits, cakes, crackers, doughnuts, fruit cakes, icings, mince meat, pies,

pretzels, puddings, sandwich fillings, etc.

Canning Industry: Fish, meats, sauces, soups, etc.

Chewing Gum Industry: Chewing gums, coated bums, etc.

Condiment Industry: Catsups, celery and other salts, chili sauces, mayonnaises, mustards, pickled fish,

relishes, salad dressings, table sauces, vinegars, etc.

Confectionery Industry: Chocolates, fondants, gum drops, hard candies, jellies, mints, panned goods,

soft center candies, etc.

Dental Preparations: Dentists’ preparations, mouth washes, tooth pastes, tooth powders, etc.


© Beverley Hawkins

Exterminators and Insecticide Supplies: Bedbug sprays, cattle sprays, cockroach powders, fly sprays,

Japanese beetle attractants, mosquito repellents, naphthalene blocks, paradichlorobenzene blocks,

plant sprays, rat baits, rodent odor eliminators, etc.

Extract Industry: Commercial extracts, home extracts, etc.

Food Industry (General): Cheeses, cornstarch puddings, dehydrated soups, meats and vegetables,

gelatin desserts, mince meats, pie fillers, prepared cake mixes, rennet desserts, sauerkraut, vegetable

oils and fats, etc.

Household Products: Bluings, deodorants, furniture polishes, laundry soaps, room sprays, starches,

vacuum cleaner pads, etc.

Ice Cream Industry: Ice creams, ices, prepared ice cream mixes, sherbets, etc.

Insecticide Industry: Attractants, disinfectants, insecticides, repellents, sprays, etc.

Janitor’s Supplies: Detergents, disinfectants, floor polishes, floor waxes, scrub soaps, sink cleaners,

sweeping compounds etc.

Meat Packing Industry: Bolognas, frankfurters, prepared meats, sausages, etc.

Paint Industry: Bituminous paints, casein paints, enamels, lacquers, paint and varnish removers, paint

diluents, paints, rubber paints, synthetic coatings, varnishes, etc.

Paper and Printing Industry: Carbon papers, crayons, drinking cups, industrial tapes, inking pads, labels,

paper bags and food wrappers, printing and writing inks, printing paper, typewriter ribbons, writing

paper, etc.

Perfume and Toilet Industry: Baby preparations, bath preparations, body deodorants, colognes, creams,

depilatories, eye shadows, facial masks, hair preparations, handkerchief extracts, incense, lipsticks,

lotions, manicure preparations, powders, room and theatre sprays, rouges, sachets, shaving

preparations, suntan preparations, toilet waters, etc.

Petroleum and Chemical Industry: Bluing oils, fuel oils, crease deodorants, greases, lubricating oils,

naphtha solvents, neoprene, organic solvents, petroleum distillates, polishes, sulfonated oils, tar

products, waxes, etc.

Pharmaceutical Industry: Anti acid tablets and powders, cough drops, elixirs, germicides, hospital

sprays, hospital supplies, inhalants, laxatives, ointments, medicinal preparations, ointments, patent

medicines, tonics, vitamin flavor preparations, wholesale druggists’ supplies, etc.

Pickle Packing Industry: Dill pickles, fancy cut pickles, sour pickles, sweet pickles, etc.

Preserve Industry: Fruit butters, jams, jellies.

Rectifying and Alcoholic Beverage Industry: Bitters, cordials, rums, vermouths, whiskies, wines, etc.

Rubber Industry: Baby pants, gloves, natural and synthetic lattices, shower curtains, surgical supplies,

synthetic rubber products of all kinds, toys, water proofing compounds, etc.


© Beverley Hawkins

Soap Industry: Cleaning powders, detergents, household soaps, laundry soaps, liquid hand soaps, scrub

soaps, shampoos, sweeping compounds, technical soaps, toilet soaps, etc.

Soft Drink Industry: Carbonated beverages, cola drinks, fountain syrups, ginger ales, root beers, soda

fountain supplies, soft drink powders, sundae toppings, etc.

Textile Processing Products: Artificial leather and fabric coatings, dyes, hosiery sizing, linoleum, oil

cloths, sisal deodorants, textile chemicals, textile oils, upholstery materials, water proofing materials,

etc.

Tobacco Industry: Chewing tobaccos, cigarettes, cigars, smoking tobaccos, snuffs.

Veterinary Supplies: Cattle sprays, deodorants, dog and cat soaps, insect powders, mange medicines

and ointments, etc.

Diversified Industries: Alcohol denaturing compounds, candles, ceramics, cleaners’ products,

embalming fluid deodorants, optical lenses, war gas simulants, etc.

When we consider all of the above it sort of puts into perspective just how little essential oil is actually

used by the proper Aromatherapy Industry.

Serious Reference Books

Encyclopedia of Common Natural Ingredients used in Food, Drugs, and Cosmetics. Second Edition,

Albert Y. Leung, Steven Foster

Herbal Medicine Expanded Commission E Monographs

Blumenthal/Goldberg/Brinckmann

Essential Oil Safety, second edition

Robert Tisserand/Rodney Young

The Essential Oils: Individual Essential Oils of the Plant Families (6 volume set)

Ernest Guenther


© Beverley Hawkins

Reference sites

International Fragrance Organization IFRA http://www.ifraorg.org/

European Federation of Essential Oils EFEO http://efeo-org.org/

Aromatherapy Trade Council http://www.a-t-c.org.uk/safety-matters/essential-oil-safety/

Research Institute of Fragrance Materials RIFR http://www.rifm.org/

Fragrance Material Safety Resource http://fragrancematerialsafetyresource.elsevier.com/

AFNOR http://www.afnor.org/en

BACIS Archives http://www.leffingwell.com/bacis/pom97051.html

International Nomenclature of Cosmetic Ingredients

http://www.cirs-

reach.com/Cosmetic_Inventory/International_Nomenclature_of_Cosmetic_Ingredients_INCI.html

International Standards Association

http://www.iso.org/iso/home.html

Medicines Control Agency UK

https://www.gov.uk/government/organisations/medicines-and-healthcare-products-regulatory-agency

Selling to the general public with a health claim

If you are going to be selling essential oils, essential oil blends or products with essential oils to the

general public, and you are making a health claim for these, your product will need to have a Product

License. You will also need to have a site license for where the products are manufactured. As

requirements can and do change over time, you need to do your own due diligence to make sure that

you are in compliance with the requirements in your country.

In Canada it is the Natural Health Products Directorate (NHPD), which is currently in the process of

changing their name to the Natural and Non-prescription Health Products Directorate (NNHPD).

http://www.hc-sc.gc.ca/dhp-mps/prodnatur/index-eng.php

In the USA it is the FDA Aromatherapy Products

http://www.fda.gov/cosmetics/productsingredients/products/ucm127054.htm

Labelling of Cosmetics in Canada

http://www.hc-sc.gc.ca/cps-spc/pubs/indust/cosmetics-cosmetiques/index-eng.php

http://efeo-org.org/

http://www.a-t-c.org.uk/safety-matters/essential-oil-safety/

http://www.rifm.org/

http://fragrancematerialsafetyresource.elsevier.com/

http://www.afnor.org/en

http://www.leffingwell.com/bacis/pom97051.html

http://www.cirs-reach.com/Cosmetic_Inventory/International_Nomenclature_of_Cosmetic_Ingredients_INCI.html

http://www.cirs-reach.com/Cosmetic_Inventory/International_Nomenclature_of_Cosmetic_Ingredients_INCI.html

http://www.iso.org/iso/home.html

https://www.gov.uk/government/organisations/medicines-and-healthcare-products-regulatory-agency

http://www.hc-sc.gc.ca/dhp-mps/prodnatur/index-eng.php

http://www.fda.gov/cosmetics/productsingredients/products/ucm127054.htm

http://www.hc-sc.gc.ca/cps-spc/pubs/indust/cosmetics-cosmetiques/index-eng.php


© Beverley Hawkins

Aromatherapist, what is your scope of practice?

I believe that it is very important for anyone calling themselves an aromatherapist, or anyone using

essential oils and/or recommending their use to the general public, should be very clear as to what their

scope of practice really is. It is imperative that we are not perceived to be 'practicing medicine without

a license' or 'prescribing' or 'dispensing'. Essential oils are extremely complex compounds and we owe it

to ourselves and those we work with to make sure that we have received adequate training and that we

really do know, and understand what it is we are doing.

Recently I receive a call from a gentleman in the States who presented himself as specializing in ‘Conflict

Resolution“. He apparently spends a lot of time working on behalf of therapists who have come into

conflict with regulation boards. He said he came across our school because he was representing one of

my graduates. However he also said that he was not at liberty to tell me who they were so I don’t know

if this is the case or not.

He apparently has spoken to both NAHA and AIA and said that neither organization could help

him. After listening to more of what he had to say, it became apparent to me that the ‘conflict

resolution’ he was dealing with, generally involved the individual adding something to their practice of

aromatherapy for which they were not additionally trained. For instance practicing massage, even

though they didn’t meet the local requirements for practicing massage where they lived or work; or

giving ‘medical advice’ and ‘dispensing’ blends or essential oils without the appropriate medical license.

Listening to the language he used around the essential oils it seemed fairly clear to me that he comes

from the multi-level marketing world of essential oils. In my opinion, this is a world where the scope of

practice is not clearly defined and where sometimes odd claims are made and less than safe practices

are followed. He also wanted to share with me a website that taught courses on being an aromatherapy

coach as a way to get around the problem.

I believe that anyone who had taken a good aromatherapy course should already know what an

aromatherapist’s scope of practice is. They should also have had training in working with the client,

taking a Health Record, understanding how to assess, the situation, plan a protocol of action, implement

it and evaluate the outcome. I certainly know that this sort of training is covered in our Full Professional

Course and I certainly expect it is covered in other courses recognized by the different aromatherapy

associations. I also believe that anyone holding a Professional Liability Insurance policy should be clear

as to the scope of practice they are covered for.

On reflection I see this phone call can serve as a good reminder to me, and my student and graduates, as

to how important it is to be clear about what we, as aromatherapists are doing, and what our legitimate

scope of practice is. As aromatherapists, we can fill an incredibly supportive role in helping people

move through the challenges they face in their journey through life. In my opinion, there are no blanket

solutions for anything. Instead we need to understand all nuances of the situation the individual is

facing including the physical, mental, emotional and spiritual aspects. While this can be a lot more work

than just saying “oh you have a headache, use this lavender”, when one takes the time to consider all

aspects of an individual, as well as their life situation and lifestyle, the synergy and protocol created are

unique for that person, allowing incredible possibilities to unfold for them.


© Beverley Hawkins

I also believe it is very important to remember that essential oils are NOT substitutes for pharmaceutical

drugs, nor should we be trying to recommend or use them in this. We should also always remember

that when it comes to a disease or a condition, as aromatherapists we NEVER treat the disease or

condition. What we do is consider the whole person, what are their concerns, what are their challenges,

what is their lifestyle, what are their physical needs, what are their psychological needs. Once we have

this information we can come up with a unique synergy for that individual, as well as a plan of action for

how that synergy is to be applied.


© Beverley Hawkins

Administration of Essential Oils

Essential Oil Pathways of Assimilation and their affect on the body and mind.

Application

Absorption

Excreation

Memory, Emotion

Learning

Intellectual processes

Pituitary gland

Endocrine System Autonomic Nervous

System

Hypothalamus

Cerebral Cortex

Hyppocampus

Amygdala

Limbic System

Brain

Olfactory Bulb

Olfactory Nerve

Nose Lungs

Inhalation

Vapour

Muscle Tissue

to Joints

Skin

Dermal

Liver Pancreas Reproductive Organs

Excreaton via

Skin

Bladder

Excreation via

Kidneys

Excreation via

Lungs

Organs and tissues

Bloodstream

Large Intestine

Small Intestine

Stomach

Oral*

Liquid

Essential Oil


© Beverley Hawkins

Methods of Application

There are a three main routes in which essential oils and/or their components enter the body.

Inhalation through the nose and respiratory system; topically through the skin and internally through

oral, rectal and vaginal administration.

Inhalation Inhalation methods carry the least amount of risk.

An increased rate and depth of breathing will enhance the uptake of gases. When essential oils are

breathed in the aromatic molecules will act on the body in two ways. When essential oils are breathed

in, the molecules rise to the top of the nose. Here they meet the olfactory mucous membrane with its

receptors made up of thousands of hairy sensory cells. The receptors identify the smell and the sensory

stimulation is passed on through the olfactory bulb, which is an amplifier, through the olfactory nerve

and directly into the limbic system of the brain.

The essential oil molecules will continue to travel along the nasal passages down into the lungs. The

whole respiratory system is lined with a thin mucus membrane which allows the absorption of gases and

volatile substances from the air. The essential oil molecules will pass down the trachea into the bronchi,

then into the bronchioles and finally into the alveoli where they will pass into the bloodstream. The

molecules can also be absorbed into the bloodstream via the nasal mucosa. According to Tisserand and

Young in Essential Oil Safety 2nd Edition, while the mucous membranes of the nasal cavity and pharynx

do make a contribution to this gas exchange, it is in the lungs with their large surface area, rich blood

supply and thin membrane separating air and blood that the absorption of gasses and volatile

substances most efficiently take place. On the out breath, essential oil components not absorbed in this

way can be breathed out. Once in the bloodstream the essential oil components will be acted on by the

body and then eliminated.

Topical Dermal Application The safe application of essential oils topically will depend on the specific oil and its components, as well

as the dosage, frequency and length of time used. Essential oils are volatile substances and some of the

essential oil synergy applied topically could evaporate off before any of the essential oil components

have an opportunity to enter into the bloodstream. The amount of time it takes for essential oil

components to be absorbed into the bloodstream will vary depending on the components, however it is

generally accepted that this will slower for dermal applications than oral applications. The

concentrations are less likely to build up to high levels as the oil components are being continually

metabolized and removed from the body.

A knowledge of the skin and its structure is necessary for understanding just how essential oil enter they

body in this application method. The whole essential oils cannot pass through the skin into the

bloodstream, after all the skin is a protective barrier between the body’s inner organs and the outer

world. The skin consists of two main layers, the outer epidermis and the underlying dermis. The

epidermis consists of sublayers, the outermost one being the stratum corneum. These are dead cells

and are constantly being shed from the body. Some essential oil components are able to stay in the

stratum corneum for several hours, so it could be thought of as a reservoir. Below the stratum corneum,


© Beverley Hawkins

is the stratum lucidum, the stratum granulosum and the germinative layer. The dermis is found beneath

these layers and is made up of collagen and elastic fibres overlying connective tissue. Blood vessels,

lymph vessels, sweat glands, sebaceous glands, hairs, sensory nerve endings and receptors are also

located in the dermis. Essential oil components can will find their way in the body through the stratum

corneum, and through sweat glands and hair follicles. Absorption through the sweat glands and hair

follicles will be faster than through the stratum corneum and will also depend on the integrity of the skin

itself.

Within the stratum corneum itself there are two pathways whereby essential oil components permeate

the skin. One which crosses the cells and intracellular spaces, and the other which passes through the

intercellular lipid domain. There are many factors that affect the rate of permeation of the essential oil

components: Biological Factions such as the integrity of the stratum corneum, skin hydration, cutaneous

blood flow, skin biochemistry, hydration; Permeant factors such as molecular weight, partition

coefficient solubility, molecular size, use of surfactants; Vehicle factors such as penetration properties,

occlusions, pH; Physical factors such as temperature, climate, time and Trauma such as mechanical,

disease, chemical.

Absorption only takes place once the essential oil components enter the cutaneous capillaries and

bloodstream.

Internal Application The internal application of essential oils is the method of application that carries the most risk. Nothing

is lost in evaporation, nothing is stopped from entering into the body through the barrier of the skin.

Therefore it is the method in which 100% of the essential oil and its active ingredients actually make

their way into the body. It should be noted that almost all recorded cases of serious poisoning by

essential oils have occurred by oral self-dosing of smaller quantities of undiluted essential oil.

Oral administration of the essential oil means that unless it is delivered in a protective capsule, the

essential oil and all its components will come into direct contact with the mucous lining of the mouth

and the whole of the digestive system. One of the disadvantages of oral dosing with essential oils is

that some of the constituents might irritate the gastrointestinal mucosa. As the level of irritation will

depend on the concentration of the essential oils it is important that the essential oil is efficiently

dispersed, or dissolved in an appropriate vehicle before being swallowed. Preferred methods would be

to administer essential oils either in capsules, dissolved in a liophilic medium such as a vegetable oil, or

in aqueous alcohol. Other concerns around oral administration include: the possibility of nausea and

vomiting; destruction of the essential oil constituents by stomach acidity or enzymes in the intestines;

and an added burden on the liver as much of the essential oil will be metabolized by the liver.

Rectal administration via suppositories. Here the essential oil are administered to the lower colon,

where they can be absorbed through the thin mucous membrane into the bloodstream. This method of

application will bypass the gastrointestinal tract and is an efficient way to administer a remedy locally to

the lower colon. It is also believed that there is a more rapid absorption of the essential oil into the

body. However as the rectum is lined with mucous membrane, it is highly sensitive to irritation,

especially if the essential oil is unevenly dispersed. Just as with oral application great caution with

respect to concentration and dispersal should be taken. In addition mucous membrane irritation can

occur with some oils.


© Beverley Hawkins

Vaginal administration via pessaries can be a convenient route for administering essential oils for the

treatment of local infections. However once again the mucous membrane lining the vagina is highly

sensitive to irritation. Great care is needed to ensure that the correct dosage and even distribution of

the essential oil is adhered to.

Because 100% of the essential oil and its components are introduced into the body in these applications,

they also carry the highest risks. These administration methods should only be used by those who have

been properly trained to do so.

Distribution, Metabolism, Excretion Irrespective of how the essential oil components are absorbed into the bloodstream, once they are

there they will be transported around the body. Essential oils are lipophilic and are carried to all organs

of the body including the brain. According to Sue Clarke in her book Essential Chemistry for Safe

Aromatherapy:

“It is believed that an essential oil does not stay in the circulation for a long period of time.

Initially it goes to areas of high blood flow such as skeletal muscle and kidney. Eventually it may

become absorbed into the fat (adipose) tissue. The blood flow to the liver is also high, and the

liver itself holds a large volume of blood. The liver is often referred to as ‘the chemical factory’ of

the body and has an important role for regulating the amounts of substances in the blood, along

with a large number of other reactions, including detoxification. Different components of

essential oils will have differing biochemical properties and reactions affecting certain tissues

and organs. Substances produced after being involved in the chemical reactions of the body

(metabolism) are lost by the process of excretion. Materials that pass through the body without

being chemically changed are lost by elimination. The time a drug or substances stays in the

body will vary from chemical to chemical. A quantitative measure of this is called the biological

half-life, the time taken for the drug concentration in the blood to decrease to half its initial

value. This is influenced by a number of factors, including transportation and metabolism of the

drug by the body and its rate of elimination. Both drugs and essential oils are excreted through

the kidneys in urine, exhaled by the lungs, secreted through the skin or passed out in the faeces.

The rate of elimination of a substance from the body is proportional to its concentration in the

bloodstream. It has been shown that most essential oils and their breakdown products are

eliminated and excreted through the kidneys, with smaller amounts breathed out from the lungs.

The skin and faeces account for the least loss.”


© Beverley Hawkins

Internal Use

I am often asked what I think about using essential oils internally or in

cooking. There are a number of sources around these days that, to my mind,

quite indiscriminately recommend the internal use of essential oils without

considering just how very complex these wonderful gifts of nature really are.

Yes it is very true that aromatic plants and essential oils have long been used

in the flavoring industry but, as anyone can appreciate using a large amount

of a fresh herb is very different to using even just a few drops of the essential oil.

The yield of essential oil from each plant can be quite different, after all not all plants yield up the same

amount of essential oil. Let us look at just a few examples:

Peppermint yields about 0.3 – 0.4% volatile oil

Spearmint yields about 0.7% volatile oil

Sweet Marjoram yields about 0.2 – 0.8% volatile oil

Rosemary yields about 0.5% volatile oil

Rose yields about 0.02 – 0.03% volatile oil

Petitgrain yields about 0.2% volatile oil

Anyone can see from this that when you have a recipe calling for a sprig (or a tablespoon) of

peppermint, or rosemary it would be a lot less than just one drop of the essential oil of peppermint or

rosemary.

In the food industry there are very good guidelines set out as to the maximum use levels in food and

beverage products for different essential oils. If we take our list above these are the recommended

maximum use levels:

Peppermint 0.104% (1040 parts per million).

Spearmint 0.132% (1318 ppm)

Marjoram 0.004% (36.2 ppm)

Rosemary 0.003% (26.2 ppm)

Rose 0.0002% (2 ppm)

Petitgrain 0.004% (37.7 ppm)

How can someone at home figure out such very small quantities when cooking at home or considering

taking an oil internally? What do we have available to measure the quantities? Our dropper insert or

pipette? The size of the drop obtained in this way will depend on the size of your dropper insert or

pipette and the essential oil itself. Some of the thicker oils will come out slowly in bigger drops, while

the more volatile ones will flow much more easily in smaller drops. How do we figure out percentages as

small as 0.104% in a regular recipe?

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© Beverley Hawkins

Let us ask ourselves why are there guidelines set up at all? Is it because of flavor intensity, or because of

the safety of using that oil internally, or a combination of the two? I don’t really know the answer to that

question but I personally believe that the safety issues are part of the guidelines.

What about using the oils internally for therapeutic purposes? In my opinion, anyone considering using

essential oils internally should know what the chemical composition of the essential oil you are

considering using in this way is and what the possible cautions of those components might be. For

instance ketones (found in quite large amounts in oils like peppermint 30%; spearmint 55%) generally

stimulate the formation of tissue, have mucolytic effects, dissolve fats, and are potentially neurotoxic.

Ketones are the most common toxic substances in essential oils. According to Dr. Penoel, ketone

molecules can penetrate the blood-brain barrier more easily than other molecules. Some of the oils high

in ketones can cause liver damage. After absorption from almost all regions of the gastrointestinal tract,

most substances pass directly to the liver, where the great majority will be deactivated but some may be

made more toxic. Not all ketones are equally problematic but this is the reason why many oils that are

high in ketones carry the caution: Do not use in pregnancy. Can the developing fetus’s liver handle the

ketone content of an oil like peppermint or spearmint?

I have heard some sources refer to using essential oils internally as the French Method, and using

them topically on the skin as the English Method. This is actually not quite accurate. If you go to

France you will be hard pressed to find a store you can walk into and just buy essential oils off the shelf

for internal use. Yes there are some Medical Practitioners, both in France and elsewhere, who prescribe

the internal use of essential oils, however this is generally for the treatment of severe infectious

diseases and not for daily everyday use. What is generally recommended/prescribed is the use of

preparations that have been carefully formulated in a laboratory and not the indiscriminate use of

individual drops of essential oil. It is important to keep in mind that all recorded cases of serious

poisoning with essential oils occurred after the ingestion of relatively large amounts of essential oils.

Yes there are definitely some essential oils that can be used very effectively internally, however, it

is imperative that their formulation in products for internal consumption is undertaken by someone

who really understands what they are working with, knows what they are doing and is able to very

carefully measure out safe dosages. And even then not all essential oils can or should be used in this

way.

Just because someone else tells you that they take a drop or two of an essential oil for a specific health

benefit daily, or that they flavor their water with a drop of essential oil, does not mean that it safe to do

so or that it will be safe for you to do so. Keep in mind that each person’s system is quite unique and

individual and not everyone’s system can deal as easily with what are relatively large doses of active

ingredients.


© Beverley Hawkins

Oral Use of Essential Oils

When I hear people talking about the oral use of essential oils I am

concerned. So many of them really don’t understand how essential oils

work. They appear to come from the mindset that one can simply substitute

an essential oil for a medical drug, not understanding that essential oils are

very complex chemical components, not single or simple ingredient

compounds. The majority of these people also appear to have little or no

medical training but they are happy to use the oils in this way and

recommend this use to others. They simply don’t recognize that more

knowledge and training is required in order to be able to recommend using essential oils in this

way. Another thing they don’t seem to be aware of is that if you are recommending using essential oils

to the public it would be a good idea to have Professional Liability Insurance. I do not know of any

Professional Liability Insurance available to Aromatherapists that will cover the oral use of essential oils,

so unless one is covered under another modality (e.g. medical practitioner; medical herbalist etc), if

someone follows your recommendation of using essential oils orally and then has an adverse reaction,

you are responsible, and if they should decide to sue, you would be facing that on your own.

Now while it is certainly true that many essential oils are used in the Food Industry as a flavoring

ingredient the amounts used are in very small parts per million. For instance, in

the Encyclopedia of Common Natural Ingredients used in Food, Drugs, and Cosmetics,

2nd Edition, Albert Y Leung and Steven Foster say:

Spearmint oil and peppermint oil (usually rectified) are extensively used in flavoring chewing

gums, candies, and chocolates as well as in most other food products, including alcoholic

(liqueurs, etc) and nonalcoholic beverages, frozen dairy desserts, baked goods, gelatins and

puddings, processed fruits, and sweet wauces. The highest average maximum use levels reported

are 0.104% for peppermint oil in candy and about 0.132% (1318 ppm) for spearmint oil in baked

goods.

This means that even in the highest dosage 0.104% for peppermint in candy, very, very little essential oil

is actually consumed at any one time. Compared to that, consuming just 1 drop of essential oil of

peppermint is almost a thousand times higher.

In their book, 2nd Edition of Essential Oil Safety, A Guide for Health Care Professionals, Robert

Tisserand and Rodney Young point out :

Much larger amounts can be administered [through Oral administration] than by other routes,

so great care must be exercised if prescribing in this way…

One disadvantage of oral dosing with essential oils is that some of the constituents might irritate

the gastrointestinal mucosa, which is generally more sensitive to insult than skin. Since irritation

is concentration-dependent, it is important that the essential oil is efficiently dispersed or

dissolved in an appropriate vehicle before being swallowed.

Oral administration always carries the potential for inducing nausea and vomiting, and the

presence of food has unpredictable effects on absorption into the bloodstream. Digestive

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© Beverley Hawkins

enzymes can break down some types of essential oil constituents, for example esters may be

hydrolyzed in the stomach. After absorption from almost all regions of the gastrointestinal tract,

most substances pass directly to the liver, where a significant proportion is deactivated in first-

pass metabolism but some, paradoxically, are made more toxic.

Virtually all recorded cases of serious poisoning with essential oils have occurred after the

ingestion of large amounts of essential oil.

With oral administration there is a greater risk of overdose, of gastric irritation, and of

interactions with medications. Therefore only practitioners who are qualified to diagnose,

trained to weigh risks against benefits, and have a knowledge of essential oil pharmacology

should prescribe essential oils for oral administration.

In my opinion, this certainly gives us some food for thought when it comes to the question

of taking essential oils orally. Obviously there is a time and place for everything, but using

essential oils orally is something, in my opinion, that one would reserve for very serious

conditions and then only under the guidance of a primary medical care practitioner.

Essential oils are extremely effective in very small doses, so why would we overload our

systems with more than we need?


© Beverley Hawkins

Should essential oils be used neat or in high percentage dilutions?

Recently there was a discussion on my student/graduate list about using

essential oils neat or in higher dilutions and in some cases internally, so I

thought that I would share some of my thoughts on this with you.

While there is merit in using SOME essential oils at higher dilutions and in

different application methods, what we do have to always keep in mind is

that NOT ALL essential oils can be used in this way. Unfortunately, this often gets lost when you are

dealing with companies selling essential oil. One can understand their position, if you can get people to

use more essential oil, you’ll sell more essential oils.

A selected number of essential oils have been prescribed for internal use or in high dilutions by

herbalists and medical practitioners in France (and other countries). However, these practitioners

always had their licensing in other modalities to back up their use of essential oils in this way. One

should keep in mind that even these practitioners would not use all essential oils in this way. The use of

essential oils in many European countries has often been reserved for those in the medical field and it

can be almost impossible to find essential oils to purchase unless you too are in that field. Perhaps with

the advent of the internet this has loosened up a bit but certainly when I lived in Europe (1985 – 1989

and again 1991/2) that was the case.

As you may know it was M. Maury who introduced the use of essential oils into the beauty industry in

England and promoted their use to a wider range of people. Because the oils were being used in a much

lower dilutions, the possibility of misuse of the oils by people with little or no training was less of a

problem and so the oils became more freely available.

Also please know that classifying an oil as a therapeutic grade oil, is a clever marketing tactic. There is no

such official classification. Although we do have official bodies who have very stringent rules on

certifying products organic, there is no such body that will, or can, certify that essential oils are of a

therapeutic grade. This means that no company has the monopoly on a ‘therapeutic grade’ essential oil.

What one needs to understand and to keep in mind is, it is the chemical profile of an oil that identifies it

as that oil. For instance Thyme essential oil will still be high in phenols no matter where it is grown. And

regardless of where it is grown or how it is labeled if you apply an oil that is high in phenols directly onto

the skin without diluting it, it has great potential for damaging the skin. Labeling an oil ‘therapeutic’

does not change its intrinsic character.

I have said this in the past and I will say it again, when using essential oils, regardless of the method of

application you choose, there are a number of things one needs to take into consideration a number of

things when formulating the synergy. These include:

How the oil/synergy to be applied?

Where is it applied?

How large a surface is covered?

How often will it be applied?

Over what duration of time will the oil/synergy be used?



© Beverley Hawkins

Aromatherapy has now been around long enough, with enough people using essential oils on a regular

basis, for us to know, and have documented, that there are oils out there that are skin irritants and oils

that are sensitizers. There are oils that have potential for great good, but also oils that, when used

incorrectly, have the potential for harm. And even mild essential oils can cause problems. It is

interesting to note that when it comes to aromatherapists being sensitized to an essential oil, the

essential oil in question is more often than not lavender. Lavender, which has for so long been

considered safe and gentle enough to be used undiluted and in larger quantities. A lesson for us all that

even gentle oils can become a problem if overused.

Another important factor to keep in mind is that not everyone reacts to an essential oil or synergy in the

same way. Skin sensitivity can vary quite considerably from one person to another. So for someone to

say ‘I have used this oil neat for years without any adverse effect, therefore it is safe for anyone to use

neat’ is neither fair nor correct. All it really means is that using that oil neat has not caused them any

harm. It does not guarantee that using that particular oil undiluted won’t cause someone else harm.

Using essential oils on oneself is one thing. If there is a problem the only person you affect is yourself

and you will learn from the experience. On the other hand using essential oils on someone else is

completely different. Anyone working with the general public should have Professional Liability

Insurance however, as none of the packages I know of here in North America will cover the use of

essential oils internally or neat, if you choose to use the oils this way with your clients and there is a

problem, you are on your own with all the responsibility of making sure that both the synergy and the

method of application is a safe one being yours and yours alone.

Essential oils are truly wonderful gifts from nature. However they are also very potent gifts and I hope

that no matter how you choose to use your oils, you do so with full understanding and great respect.


© Beverley Hawkins

Skin Sensitization

There are two different types of skin reactions that can occur when using

essential oils topically. They are quite different and are often initiated by

different chemical components in an essential oil.

Skin irritations will sometimes occur in one individual and not in another and

this is because the skin of one might be sensitive to a particular component in

the essential oil. Skin irritation happens on the first exposure to the irritation, the reaction is rapid and

the severity will depend on the concentration of the irritant present. The skin responds with an

inflammatory reaction. So when you see an essential oil with the caution that it may be a skin irritant

use it with caution on people with sensitive skins.

Skin sensitization is a type of allergic reaction. The oil may not produce any reaction on the first contact,

however once the allergen has penetrated the skin, the body’s immune system reacts to fight off the

invader causing a rash on the skin. Sensitization reactions can also take the form of inflammation,

breathlessness, nausea or headache. It is actually possible to become sensitized to any essential oil.

Sensitization to an essential oil can happen through overuse of any oil and an interesting fact is that

Lavender (Lavendula angustifolium), the essential oil with the reputation of being one of the most

versatile and safest essential oils around, is the one that most therapists have become sensitized to. This

happens mainly through overuse of the oil, a good reminder that we should not just use the same oil or

blend of oil day in and day out but we should change our blends around on a regular basis.

Whenever you feel there is a possibility of skin irritation or skin sensitization patch test first.

To patch test with a particular oil:

Place one drop of carrier oil or lotion on your breastbone, or behind your ear.

Leave for 12 hours.

If there is no adverse reaction, dilute one drop of the essential oil in half a teaspoon of the

carrier oil or lotion, and rub the mix on your breastbone or behind your ear.

Allow 12 hours for any reaction to show.

If there is an adverse skin reaction:

Wash the skin gently with unperfumed soap to remove most of the oils that are on the surface

of the skin.

Expose the skin to air (but not strong sunlight) to encourage the evaporation of the essential

oils.

Essential oils of Yarrow (Achillea millefolium) and German Chamomile (Matricaria recutita)

have been found to counter irritation and sensitisation reactions. They should always be

properly diluted in a carrier before application.

Cross-sensitization: Keeping in mind that each essential oils is a complex mix of many different

chemical components, it is generally not the ‘whole’ essential oil that one becomes sensitized to but

rather one or more of its chemical components. When this happens it is possible that one can be



© Beverley Hawkins

susceptible to becoming sensitized to other essential oils containing the same chemical components.

Thankfully this does not happen very often.

Some Factors Increasing the Absorption of Essential Oils:

Warmth and massage both enhance absorption, as does hydrating the skin before oil

application.

Covering the skin following massage aids absorption.

Damaged skin is more permeable than undamaged skin, and so essential oils should be applied

to it with caution. Applying essential oils to damaged skin is one of the ways that could increase

the likelihood of skin sensitization.


© Beverley Hawkins

Misconceptions about Reactions to Essential Oils

Last week there was a discussion on my student list which was started by one

of the students asking about possible reactions to essential oils. In this

discussion it was brought to my attention that, there is a particular company

selling essential oils, who claims that any reaction experienced from using

their brand of essential oils is never an allergic reaction. Nor is it due to skin

sensitivity, it is simply the body taking the opportunity to “detox”.

I did a little bit of research myself today and what I found was truly concerning. In my opinion, none of

the explanations given are grounded in any real understanding of the true nature of either essential oils

or the anatomy and physiology of the human body. It is my belief that if these people truly understood

how the body functioned, they would see that their claims make no sense at all. If they understood the

true nature and chemical complexity of essential oils they might see that the explanations that they are

given are not grounded in reality at all.

For instance in answer to these questions:

What is a skin rash? Dictionary.com defines it as – any red eruption of the skin.

What causes a skin rash? WebMD Says: Healthy skin provides a barrier between the inside

of the body and the outside environment. A rash means some change has affected the skin.

Rashes are generally caused by skin irritation, which can have many causes. A rash is

generally a minor problem that may go away with home treatment. In some cases a rash does

not go away or the skin may become so irritated that medical care is needed.In adults and

older children, rashes are often caused by contact with a substance that irritates the skin. In

adults and older children, rashes are often caused by contact with a substance that irritates

the skin (contact dermatitis). The rash usually starts within 48 hours after contact with the

irritating substance. Contact dermatitis may cause mild redness of the skin or a rash of small

red bumps. A more severe reaction may cause swelling, redness, and larger blisters. The

location of the rash may give you a clue about the cause.

Therefore I find it quite logical to believe that if an essential oil is applied to the skin and the skin

reddens up it means that the skin itself has been irritated by the substance applied to it.

Easy to understand information on how the skin and immune system really works is freely available on

the internet today. HowStuffWorks Human Body Immune System

(http://health.howstuffworks.com/human-body/systems/immune/immune-system4.htm) or

NetDr.Co.UK Immune System and the skin (http://www.netdoctor.co.uk/conditions/skin-and-

hair/a3653/the-immune-system-and-the-skin/) are certainly two places to start.

If the skin is going to react to an essential oil it will react to it, regardless of what label appears on the

bottle. The reason a person’s skin reacts to an essential oil has everything to do with the chemical

composition of that particular essential oil and the way the skin naturally functions.

http://science.howstuffworks.com/life/human-biology/immune-system4.htm

http://health.howstuffworks.com/human-body/systems/immune/immune-system4.htm

http://www.netdoctor.co.uk/skin_hair/skin_immune_system_003741.htm

http://www.netdoctor.co.uk/conditions/skin-and-hair/a3653/the-immune-system-and-the-skin/

http://www.netdoctor.co.uk/conditions/skin-and-hair/a3653/the-immune-system-and-the-skin/



© Beverley Hawkins

What are essential oils? Basically essential oils are naturally occurring aromatic compounds that are

created during secondary metabolism in some plants. They are highly complex chemical compounds

with many useful properties.

The essential oils are extracted from the plant material in a number of different ways, distillation (steam

and water) being the most frequently used method, cold expression, enfleurage, solvent extraction

(technically an absolute not an essential oil) and carbon dioxide extraction. Each essential oil is a

complex combination of many different chemical components. If we test an oil we will get a listing of

the chemical components in that oil. When checking this against the chemical profile of that oil we

would expect the oil to contain specific chemical components and these specific components are also

expected to fall within a specific range. It is from these chemical components that each essential oil

gets its wonderful healing properties, but it is also these chemical components that can bring the

cautions and contra-indications to an oil.

Let’s use Thyme (Thymus vulgaris) belonging to the Labiatae family as an example. There are a number

of chemotypes available for this oil, but let us compare the two chemotypes most readily

available. Thymus vulgaris ct. thymol and Thymus vulgaris ct. linalool. One would expect Thymus

vulgaris ct. thymol (red or white thyme) to have the following chemical profile: Esters 2%; Ketones 9%;

Sesquiterpenes 1.5%; Oxides 4%; Monoterpenes 25%; Alcohols 17%; Phenols 40%; while Thymus

vulgaris ct. linalool(Sweet Thyme) would have a somewhat different chemical profile: Esters 40%,

Sesquiterpenes 4%; Alcohol 54% and Phenols 2%. While I have given exact percentages for the

functional groups, they actually occur within an accepted range of percentages. The actual amounts can

vary depending on many different factors, such as climate, where the plant was grown, how it was

harvested, stored, distilled etc. etc.

From Organic Chemistry we know that of the functional groups found in both Thymes the group most

likely to cause skin irritating properties would be the Phenols.

Phenols are formed when a hydroxyl group (an oxygen and hydrogen bonded together) is joined to a

benzene ring. They have bactericidal, immune stimulating, skin irritating and warming properties. They

are potentially toxic. Therefore it follows that any compound containing phenols would have

bactericidal, immune stimulating, skin irritating and warming properties. Based on their chemical profile

we can see that Thymus vulgaris ct.thymol with 40% phenols would be a lot more skin irritating

than Thymus vulgaris ct.linalool which only contains around 2% phenols.

In order for an oil to be Thymus vulgaris ct. thymol it would have to contain around 40% phenols and

therefore regardless of who you purchase this oil from it will have skin irritating properties.

I do hope that instead of just taking everything said at face value, people will use their own common

sense and get a true understanding of what is actually going on.


© Beverley Hawkins

Phototoxicity

Have you seen the precaution – If applied to the skin avoid sunlight or UV rays (including

sun beds) for 12 hours or something similar on some essential oils or essential oil blends

and wondered what this was all about?

Phototoxicity is a reaction that can occurs on the skin when it is exposed to sunlight (or

UV rays) in the presence of certain chemicals. The most common phototoxic agents are

psoralens, or furocoumarins. These polycyclic molecules have a structure that gives them

the ability to absorb ultra violet photons, store them for a while and then release them in a

burst on to the skin.

The reaction will only occur if the sensitizing agent is present on the skin when it is

exposed to Ultra Violet light and can take the form of a mild color change all the way

through to deep weeping burns. Sometimes the skin is able to revert back to normal over

time, but at other times the reaction can be permanent. The reaction can occur almost

immediately, or it can be delayed and only occur following a period of sensitazation.

Only a few essential oils contain these phototoxic components and while it is usually in

amounts of less than 2%, even at this low level and even when the oil is diluted down

with a carrier to a 1 – 3% dilution, they are still often capable of producing phototoxic

effects if the skin is then exposed to sunlight or UV rays. If these essential oils were to be

used undiluted or if the skin were to be exposed to concentrated UV light or strong

sunlight then a very severe phototoxic effect could occur.

Expressed Bergamot essential oil has been found to be one of the more phototoxic

essential oils. It is an oil that has been used extensively in perfumes (especially eau de

cologne), creams, lotions and soaps. Studies in the 1950s and 60s showed that, in the

presence of UV light, a reaction took place between furanocoumarins and the skin. In

France in 1970 J Meyer reported problems with a tanning lotion containing bergamot

essential oil, and in 1972 Urbach & Forbes reported that severe phototoxic effects were

experienced when humans were treated with expressed bergamot oil and stimulated

sunlight. A number of other studies have confirmed the photoxicity of express bergamot

oil. The bergapteen (a furocoumarin) in bergamot oil was found to produce abnormally

dark pigmentation and reddening of the surrounding skin after exposure to an ultraviolet

lamp. This condition is called berloque dermatitis, or bergapten dermatitis. The patches of

darkened skin characteristic of this condition can remain for many years.

As mentioned above it is the furocoumarin bergapten present in bergamot expressed

essential oil that causes the reaction. Today one is able to purchase an essential oil of

bergamot that has been rectified to remove this furocoumarin – known as Bergamot FCF

while this is certainly a much safer oil to use on the skin as it does not contain the

phototoxic chemical, many find that its aroma is inferior to the aroma of expressed

Bergamot oil.


© Beverley Hawkins

The risk of phototoxicity when using some essential oils not only depends on the

presence of a furocoumarin but also the type of furocoumarin and how much of it is

present.

When citrus essential oils are extracted by expression (a process where the skin of the

fruit is punctured and the essential oil is released), all the chemical components present

in essential oil in the skin of the fruit come across into the essential oil collected including

the furocoumarins which are fairly large components. However furocoumarins are

physically too large to make it across a steam distillation process so when citrus essential

oils are produced by steam distillation there is no longer the problem of phototoxicity.

Essential Oils that are strongly phototoxic include:

Expressed Bergamot

Lemon Verbena

Taget

Expressed Lime

Rue

Opopanax

Essential oils that are moderately phototoxic include:

Expressed Orange, Bitter

Expressed Lemon

Cumin

Essential Oils that are mildly phototoxic include:

Angelic Root

Caraway

Cassia

Cinnamon Bark

Citrus Essential oils that are Not phototoxic include:

Bergamot FCF (bergaptene free)

Lemon – steam distilled

Lime – steam distilled

There exists a bit of disagreement on some of the classifications on phototoxicity:

Expressed grapefruit is classified as moderately phototoxic by one source and mildly phototoxic by

another.

Expressed mandarin is classified as moderately phototoxic by one source and not phototoxic by another.

Expressed Orange, sweet is classified as not phototoxic by one source, but Orange (unspecified sweet or

bitter) is classified as moderately phototoxic by another source.

I would suggest that when in doubt exercise caution and consider that all expressed

citrus oils could be phototoxic while steam distilled citrus oils, or bergamot FCF are not.


© Beverley Hawkins

Also keep in mind that as phototoxicity or photosensitization is a reaction that takes place

between the skin and the phototoxic component in the essential oil, inhalation of the oil

doesn’t usually cause the same reaction.


© Beverley Hawkins

Interactions between essential oils and coumadin (warfarin) and other

considerations.

Recently one of my students posted to our student/graduate group asking whether any essential oils

would be contra-indicated for someone on Coumadin and I thought that this would be a good topic for

the blog.

Coumadin, one of the brand names for warfarin, is an anticoagulant. Originally it was launched in 1948

as a rat poison and is in fact still available for this purpose. At first it was thought to be too toxic for

human consumption, however in 1951, the failed suicide attempt of a navy recruit who had taken a

large dose of rat poison led clinicians to discard dicumarol in favour of warfarin. The first clinical study

with warfarin was reported in 1955. In the same year, President Eisenhower was treated with warfarin

following a heart attack. In the early 1950’s it was approved for use as a medication and today it is the

most widely prescribed anticoagulant drug in North America. However, there is a downside, warfarin

can interact adversely with a number of commonly used medications as well as some foods. It is

important therefor that its use is monitored by frequent blood testing to ensure that an adequate and

safe dose is being taken. There is a lot of information available on the web on coumadin (warferin)

however here is a summary of some of the cautions to keep in mind.

Warfarin is contraindicated in pregnancy.

The only common side effect of warfarin is hemorrhage (bleeding).

The risk may also be increased in elderly people.

Avoid sudden changes in dietary habits. Avoid ingesting unusual increases or decreases of foods high in

Vitamin K (liver, broccoli, cauliflower, cabbage, kale, spinach and other green leafy vegetables, green

tea, certain vegetables, cheeses and certain vitamin supplements). It is best to avoid strictly vegetarian

diets that consist of foods high in vitamin K.

Many commonly-used antibiotics, will greatly increase the effect of warfarin by reducing the metabolism

of warfarin in the body. Other broad-spectrum antibiotics can reduce the amount of the normal

bacterial flora in the bowel, which make significant quantities of vitamin K, thus potentiating the effect

of warfarin.

Thyroid activity also appears to influence warfarin dosing requirements.

Excessive use of alcohol affecst the metabolism of warfarin and people taking warfarin are often

cautioned against the excessive use of alcohol.

Many drugs interact with warfarin.

Warfarin also interacts with many herbs and spices, both those eaten in food (e.g. ginger and garlic) and

those used for medicinal purposes (e.g. ginseng and Ginkgo biloba). All may increase bleeding and

brusing in people taking warfarin; similar effects have been reported with borage (starflower) oil or fish

oils.St. John’s Wort, sometimes recommended to help with mild to moderate depression, interacts with


© Beverley Hawkins

warfarin; it induces the enzymes that break down warfarin in the body, causing a reduced anticoagulant

effect.

And what about essential oils?

Methyl salicylate is the component to be aware of. When applied topically to the skin it is absorbed

transdermally without any problem, quickly finding its way into thebloodstream and once there it can

potentiate the anticoagulant effect of warfarin and could cause internal hemorrhage. Methyl salicylate

is a component found in many liniments, however it is also found in large quantities in the essential oils

of Sweet Birch (Betula lenta) andWintergreen (Gaultheria procumbens) both of which are composed

of naturally occurring methyl salicylate at around 98 – 99%. This makes it a very easy oil to adulterate by

simply adding synthetic methyl salicylate. While there are those who find these oils to be very effective

in sports therapy, muscle blends etc, if you must use then, do it with great care and only over very short

periods of time.

Robert Tisserand and Tony Balacs, in their book Essential Oil Safety, say: These oils should not be used

in therapy, either internally or externally. Do not use if taking anticoagulants (e.g. aspirin and heparn).

Also in Essential Oil Safety, Robert Tisserand and Tony Balacs have a listing on bloodclotting mentioning

that both garlic and onion oils demonstrate anti-platelet activity which is essential for blood clotting.

However these are not two oils that one would find in most aromatherapist’s kit. They do however say

that :

Anti-platelet activity is also demonstrated by eugenol and iso-eugenol and is due to an anti-

prostaglandin action. It would be prudent to avoid oral administration of garlic oil, onion oil, and all

eugenol-rich oils in those with blood clotting problems. This group includes people with haemophilia,

liver disease, kidney disease, prostate cancer and systemic lupus erythematosus. It would be prudent for

anyone taking anticoagulant drugs, such as aspirin, heparin and warfarin to avoid oral use of the same

group of oils.

Note the method of use they are talking about is oral. All the other references for contra-indications for

herbs and warfarin I was able to find in the reference books I have on drug-herb-vitamin interactions

were also for the oral use of the herb. If you wanted to carry this over to the use of the essential oil,

then it would pertain to the oral use of the essential oil. With the exception of Birch and Wintergreen,

essential oils applied topically on the skin or by one of the inhalation methods should not present a

problem. Oils taken internally might. Another reason why we don’t recommend the internal use of

essential oils unless one has had specific, extensive training in that method.


© Beverley Hawkins

Adverse Reactions to Essential Oils

Any one experiencing adverse reactions to essential oils should seek immediate medical attention, call

911, Poison Control or your medical doctor.

Poison Centres in Canada Accidental poisoning is a common cause of injuries in Canada. A selection of helpful materials on how to

prevent accidental poisonings in your home is available at the site of the Canadian Association of

Poison Control Centres. http://www.capcc.ca/resources/resources.php

ISMP Canada recommends that you confirm the telephone number of the poison centre for your area

and post it in a visible place in your home.

Alberta: Poison and Drug Information Services (PADIS) Toll-free 1-800-332-1414

British Columbia: British Columbia Drug and Poison Information Centre Toll-free 1-800-567-8911 (604)

682-5050

Manitoba: Manitoba Poison Control Centre Toll-free 1-855-7POISON (1-855-776-4766)

New Brunswick: 911

Newfoundland and Labrador: Poison Information Centre - Toll-free 1-866-727-1110 (709) 722-1110

Northwest Territories: Poison and Drug Information Services (PADIS) Toll-free 1-800-332-1414

Nova Scotia: IWK Regional Poison Centre Toll-free 1-800-565-8161 (within Nova Scotia and Prince

Edward Island) or call 911 and ask to speak to the Poison Centre

Nanavut Toll-Free 1-800-268-9017

Ontario: Ontario Poison Centre Toll-free 1-800-268-9017 (within Ontario) (416) 813-5900 (Greater

Toronto Area)

Prince Edward Island: IWK Regional Poison Centre Toll-free 1-800-565-8161

Québec: Québec Poison Control Centre (Centre antipoison du Québec ) Toll-free 1-800-463-5060

Saskatchewan: Poison and Drug Information Services (PADIS) Toll-free 1-866-454-1212

Yukon Territory: Yukon Poison Control Centre - Whitehorse General Hospital (867) 393-8700

Poison Centres in the USA Poison Control 1-800-222-1222 www.poison.org

There are 55 poison centers in the United States of America. Your call will be routed to the center that

serves you, based on your area code and exchange.

Poison Centres Elsewhere If you live outside of Canada and the USA then source out your local Poison control Centre.

http://www.capcc.ca/resources/resources.php

http://www.capcc.ca/resources/resources.php

http://www.capcc.ca/

http://www.capcc.ca/

http://www.poison.org/

Documents

A Quick Guide to Essential Oils and Essential Oil Safety€¦ · Yes essential oils do come from nature, but it is important to understand that they are very concentrated, complex