The power of one of our five senses: Smell. Learn about essential oils.

WARNINGS about essential oils

Avoid exposure to UV (sun) as some of the chemicals these essential oils can be photoreactive.

Chemicals in this blend are knows allergens. Discontinue usage if irritation is observed.

Use only in dilute form and only in topical products.

Are you going to Scarborough Fair?
Parsley, sage, rosemary and thyme
Remember me to one who lives there
For once she was a true love of mine

From Scarborough Fair/Canticle by Simon and Garfunkel

What are essential oils? They are not essential for our body (the way that essential fatty acids are). They are called “essential” because the contain the “essence” of the smell of the flower or fruit or the part of the plant that has the smell.

The smell is in the chemicals. Plants have the capacity to make very complex chemicals, which they use to attracts pollinators, get rid of predators, and kill viruses, bacteria and fungi. Many plant diseases are caused by viruses. Some of those chemicals trigger our sense of smell.

The very volatile molecules in these oils reach the olfactory bulbs in our noses giving us great pleasure. Essential oils are extracted from a variety of plants and contain the volatile chemicals that can be evaporated by water steam. The high price of some essential oils is due to the very low yield, i.e. many pounds of plant material need to be treated to get just a few drops of essential oil. Some of the volatile compounds present in essential oils are terpenes, with the most abundant terpenes being linalol (in the essential oil of lavender), 2-Z-citral (lemongrass), santalenes (sandalwood), patchouli alcohol (patchouli), and geraniol and citronellol (rose).  Other terpenes common in essential oils include limonene, menthol and farnesol.

Physiology of Smell

The perception of an odor effect is a two-step process. First, there is the physiological part. This is the detection of chemicals by receptors in the back of the nose. The stimuli are recognized by the region of the human brain which handles olfaction.

You are probably familiar with the potato disease that initiated the great migration of Irish people to the Americas.  That was caused by Phytophthora infestans or potato late blight fungus.

Just like humans can be (or become) resistant to infections, so can plants, but the mechanisms of resistance are completely different. Still, plant chemicals that kill viruses may also kill viruses that attack humans.

Although the chemicals that kill plant viruses may not be effective to defend us from the common cold or the much more dangerous coronavirus 19, they may help. And they can also help us by bringing us back to our childhood, through our psychologically potent sense of smell.

The smell of cookies in the oven give us a sense of wellbeing, and the vivid smells of herbs that have essential oils can make us feel better. Just make sure you like the smell!

Skin Actives special essential oil mix. Essential Components:

Minthostachys mollis. Peperina, leaf oil. Peperina is an aromatic plant that grows wild in the valleys of the province of Cordoba, in Argentina. It has been used for its medicinal properties for centuries. The essential oil has antiviral activity against herpes simplex type 1 (HSV-1), and against bacteria and fungi.

Eucalyptus citriodora (Lemon Eucalyptus) Leaf Oil, from the wood and leaves of eucalyptus Analgesic, anti-bacterial, anti-inflammatory, antiseptic, antiviral. It contains mainly oxygenated monoterpenoids, monoterpene hydrocarbons, sesquiterpene hydrocarbons, oxygenated sesquiterpenes and other non-terpenoid compounds.

Lavender (Lavandula sp.) extract and essential oil. Lavender beautiful scent is the usual reason for using it, but its leaves also contain chemicals with antiseptic, antibacterial and analgesic properties, like camphor and cinnamaldehyde.

Rosmarinus officinalis (Rosemary) Leaf Oil. Rosemary contains a number of phytochemicals, including rosmarinic acid, camphor, caffeic acid, ursolic acid, betulinic acid, carnosic acid, and carnosol. Rosemary essential oil contains 10–20% camphor.

Citrus limon (Lemon) Peel Oil. This “pharmacy in a peel” contains monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpenes, and fatty alcohol esters. Among the monoterpene hydrocarbons, d-limonene, beta-pinene, and gamma-terpinene were the most abundant; and among the oxygenated monoterpenes, alpha-terpineol, nerol, and geraniol.

Lavandula × intermedia, a.k.a. lavandin or Dutch lavender Flower Oil, contains linalool, linalyl acetate and camphor.

Eugenia caryophyllata (Clove) Stem Oil, contains phenylpropanoids such as carvacrol, thymol, eugenol and cinnamaldehyde. I n addition to its antimicrobial, antioxidant, antifungal and antiviral activity, clove essential oil possesses anti-inflammatory, cytotoxic, insect repellent and anaesthetic properties

Syzygium aromaticum (Turkish clove) eugenol, eugenyl acetate, gallic acid and β-Caryophyllene.

Backhousia citriodora (Lemon Myrtle) Leaf Oil contains neral, geranial, iso-citral, exo-citral and many more

Origanum majorana (Marjoram) Leaf Oil. Contains terpinen-4-ol, cis-sabinene-hdyrate, p-cymene, sabinene, transsabinene hydrate and α-terpineol.

Origanum vulgare (Oregano) Leaf Oi contains carvacrol and γ-terpinene

Cymbopogon martinii (Palmarosa, Lemongrass) leaf oil contains geraniol, geranyl acetate and linalool

Salvia officinalis (common sage) Leaf Oil cis-thujone, camphor, cineole, humulene trans-thujone, camphene, pinene, limonene, bornyl acetate and linalool

Always remember that ethnic medicines were the medicines of the people who had no access to modern evidence-based medicine.  They had no inhibitors of the reverse transcriptase, no neuraminidase blockers, no vaccines, no science, so they had to content themselves with magic amulets and prayers, and, of course, medicinal plants. This does not mean that essential oils and medicinal plants are inactive. Among the many types of chemicals that give leaves and flowers their smell there are terpenoids, flavonoids and many more that have been shown to inhibit viral replication and virus binding. They will not give you immunity or anything reliable, but they will help a bit and comfort the spirit with the smells of old medicines our grandparents used to use.

So, please, in these difficult times, when there is a pandemic that kills, please forget magical thinking and use the tools that science and medicine can offer you. They may not be much right now, when we haven’t yet found effective antiviral drugs that can stop this particular virus or a vaccine that will direct your immune system in the right direction. But epidemiologist know how to slow down contagion. And remember the brave people of Eyam, the village in Derbyshire, England, who knew enough about the Black Death to isolate themselves to save their neighboring towns.

Essential oils in a picture (a picture is worth one thousand words).

Figure 2 from Hwa-Jung Choi (2018) Chemical Constituents of Essential Oils Possessing Anti-Influenza A/WS/33 Virus Activity . Osong Public Health and Research Perspectives 9: 348-353. DOI: https://doi.org/10.24171/j.phrp.2018.9.6.09

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