Thymol

What is Thymol?

Thymol is a compound found primarily in thyme oil, but also in other herbs including ajowan seeds and horsemint. The compound is a phenol, which means that its chemical composition includes a hydroxyl group bound to an aromatic hydrocarbon group. Phenols are similar to alcohols but have a number of unique properties. Many phenols, including thymol, are highly germicidal and have been used in this application for a long time.

Thymol has been used since ancient times as a preservative, thanks to its antimicrobial properties. It was one of the ingredients used by the ancient Egyptians during the mummification process. It was also used in the book binding industry to prevent fungal spores from destroying the paper and bindings of the books.

A study from 2006 found that thymol was specifically useful against E. coli and Staphylococcus bacteria. The compound caused disruption in the cell walls of the bacteria, causing the cytoplasm to leak out and destroying the cell. The same study also found that it was useful against such parasites as hookworms.

Thymol has been used in the honey industry, as it prevents a type of mite that attacks honey bees, called Varroa, without doing any harm to the bees or to humans. Although the residue of the compound can be found in the wax of the honey comb, the only negative effect it is known to cause is a slight flavor change in the honey.

Today, thymol is sometimes used as a pesticide and will safely repel wild and domestic animals. For example, spraying a garden with a tincture using this compound can help to repel deer without harming the plants in the garden. Additionally, spraying your garbage cans can help deter raccoons. The Environmental Protection Agency does not list the compound as having any potential dangers to humans, domesticated animals or wildlife. 

The compound is often produced synthetically and is used as an additive in food as well as in a number of natural-based remedies that are used as antimicrobials. It is often used  to treat and prevent fungal infections in the nails and is a common ingredient in many oils and ointments used to treat aching joints and sore muscles.

Other preparations in which this phenolic compound can be found include:

-- Perfumes
-- Mouthwash (Listerine, for example)
-- Cosmetics

Thymol is used for the composition of oregano essential oil along with carvacrol. It can be found in preparations to treat everything from athlete's foot to acne and is one of the active ingredients in the over-the-counter medication Vicks Vaporub, which is used to treat coughs and chest colds.