Danger of Tarragon Essential Oil: myth or reality?
Basil and Tarragon Essential Oil containing estragole have been used since ancient times without ever presenting any real toxicity for humans and animals. The main constituents of Basil essential oil are estragole (methyl chavicol) 74% and linalool 19.5% and the main constituents of Tarragon essential oil are estragole 70% and Trans and Cis-b-OCIMENE 25%. The percentage of estragole may be higher in certain species (85%).
Unfortunately, the high percentage of estragole has given these plants a bad reputation. They are said to be dangerous, toxic, carcinogenic, not recommended for aromatherapy, etc. Is there any danger in tarragon essential oil ? We'll explain!
Danger of Tarragon Essential Oil: what is it really?
No risks for tarragon or basil
Methyl Chavicol, or estragole, is one of the 'alkyl benzenes'. It is from the same family as safrole (from sassafras), methyl eugenol, anethole and even elemicin. Some of these compounds, notably safrole, have been shown to be carcinogenic in some studies. This has led to safrole being only allowed in tiny quantities in foodstuffs and perfumes, or even banned altogether.
Estragole also showed a genotoxic signal in rodents and has been the subject of numerous studies. But until now, no European or American government authority has banned the use of estragole or the plants, oils, dietary supplements, perfumes and medicines that contain it. The concentrations concerned are considered too low to be genotoxic. There is therefore no danger in tarragon essential oil.
Studies have shown that estragole, by itself, is not genotoxic and non-carcinogenic (that is, can cause cancer by damaging cellular DNA), but rather it is a metabolite derivative, resulting from the metabolization of alkyl benzene which is genotoxic.
Quantities too small to be dangerous
The metabolite in question for estragole is hydroxyestragole . It metabolizes to sulfooxyestragole and hydroxyestragole oxide. These compounds, in high doses, can induce mutations at the DNA level and, possibly, be carcinogenic.
You should know that hydroxyestragole can only be produced by metabolization from a large quantity of estragole. In the case of laboratory rodents, 0.5 g/kg body weight is required. By comparison, an adult weighing 70 kg requires a dose of 35 grams per day , that is to say approximately 47 grams (50 ml) of tarragon or basil essential oil very rich in estragole. However, this is a huge quantity that you will never consume with a few drops of oil here and there!
With smaller doses of basil essential oil, hydroxyestragole is only formed or produced in tiny amounts in the essential oils .
Studies not very representative of the effects on humans
Studies with estragole have shown that the NOAEL (No observable adverse effect level) in rats and mice is approximately 260 mg/kg on average. This is the equivalent of 23 grams (25 ml) of basil essential oil for a 70 kg adult.
It should be noted that in these genotoxicity and carcinogenicity studies, we have always used high doses of pure estragole (isolated) and not in a mixture as is the case with plant extracts or essential oils. The overall effect and the protective potential of the interactions of other molecules present in an essential oil or in a plant extract have not been studied.
In a recent study '2008', Jeurissen, SMF et al. show that the bioactivation of hydroxyestragole and the harmful effects of its derivatives could be reversed if basil extract is used instead of estragole alone. This group of researchers showed that basil extract completely inhibits the aberrations induced by pure hydroxyestragole on the DNA of human hepatoma HepG2 cells.
According to the FDA and FEMA*
Basil essential oil is approved by the US Food and Drug Administration (FDA) for food use (21 CFR. Code of Federal Regulation) 121.1164). And it is considered GRAS (Generally Recognized As Safe) by 'The Expert Panel of the Flavor and Extract Manufacturer's Association' (FEMA).
According to the European Agency for the Evaluation of Medicines*
Use of plants with high methyl chavicol (estragole) content should be minimized for children, pregnant and lactating women until further studies on low levels of estragole exposure are conducted. .
The benefits of tarragon essential oil
Now that we know that there is no danger in tarragon essential oil , let's discover all the virtues of this natural health solution ! Rich in antispasmodic compounds, tarragon essential oil is widely used in cases of hiccups, digestive spasms or stomach aches. Its properties also help relieve an asthma attack or seasonal allergic reaction.
The use of tarragon essential oil is known to improve digestive tone, relieve hiccups, modify the allergic terrain and fight against antivirals and antifermentatives. Its application is recommended in cases of aerophagia, slow ingestion and digestion, gastritis and colitis. It is effective against premenstrual pain, spasms and dysmenorrhea.
Its use is mainly in skin application, with a few drops to be diluted mixed in your oily preparation and massaged on the abdomen.
In terms of precautions, we do not recommend this plant for people who take anticoagulant medications or who experience coagulation disorders. Oral use is totally prohibited!
Bibliographic references:
- Ron Guba, Beneficial Basil, Essential News, Essential Therapeutics, The Ultimate Practitioner Range Vol. June 18, 2005
- Aruna K, Sivaramkrishnan VM. Plant products as protective agents against cancer. Indian Journal of Experimental Biology 1994; 47 (11): 2063-2068
- Mills S, Bone K. Principles and Practice of Phytotherapy Churchill Livingstone 2000, p157
- Final position paper on herbal medicinal products containing estragole. The European Agency for the Evaluation of Medicinal Products March 2004.
- Suzanne MF Jeurissen, Ans Punt, Thierry Delatour, Ivonne MCM Rietjens. Basil extract inhibits the sulfotransferase mediated formation of DNA adducts of the procarcinogen 1'-hydroxyestragole by rat and human liver S9 homogenates and in HepG2 Human Hepatoma Cells. Food and Chemical Toxicology 46 (2008) 2296–2302
- *182.20 Essential oils, oleoresins (solvent-free), and natural extractives (including distillates) that are generally recognized as safe for their intended use. US Department of Health and Human Services FDA Center for Food Safety. 21 CFR Ch. I (4–1–06 Edition). § 182.20. P.469
- *Final position paper on herbal medicinal products containing estragole. The European Agency for the Evaluation of Medicinal Products. European Medicines Agency. Evaluation of Medicines for Human Use. London 23 March 2004, EMEA/HMPC/337/03
- *Public Statement on the use of herbal medicinal products containing estragole. The European Agency for the Evaluation of Medicinal Products. European Medicines Agency. Evaluation of Medicines for Human Use. London, 23 November 2005. Doc Ref: EMEA/HMPC/137212/2005
