From leaves of several species of Melaleuca, essential oils of tea tree, niaouli or cajeput are used in the composition of food supplements, originally for their antimicrobial properties. However, some consumers “divert these food supplements to make adjunct treatments with a view to treat certain infections (tonsillitis, sinusitis, cystitis, etc.)“, reports the National Health Security Agency (ANSES) in a new news item dating from December 16.
The problem is, these essential oils (ETs) are not safe when ingested. They are even not recommended or even prohibited in certain European countries due to their potential neurotoxic effects. Entered to study the risks associated with their ingestion, ANSES confirms that, in the current state of knowledge, theoral absorption certain compounds of essential oils of Melaleuca presents neurological (niaouli and cajeput), carcinogenic, genotoxic and potentially reprotoxic risks.
Three potentially harmful substances in tea tree essential oil
In its expert appraisal, ANSES identified substances “worrying”In the essential oils in question. For the tea tree, it is:
- of terpinen-4-ol, the major component exhibiting testicular toxicity in rats,
- of methyl eugenol, substance present in very small quantities but considered to be genotoxic and carcinogenic to humans,
- of the’ascaridole, a substance that appears if the essential oil is not properly stored and whose toxicity is poorly documented.
For the tea tree, the health risk is complicated to assess since “depends on the contents of these compounds in essential oils, the number of drops consumed, the size of the drops delivered by the dropper bottles and the body weight of the consumer”. ANSES therefore recommends that manufacturers determine the maximum number of drops to consume per day and, for this, take into account the various factors mentioned above. In addition, to prevent the formation of ascaridole, the consumer should be informed of the need to keep tea tree essential oils cool and in the dark.
HE of niaouli and cajeput: ANSES recommends banning them for children under 30 months
For essential oils of niaouli and cajeput, the possible health risk would come from the 1,8-cineole, a major component that has resulted in neurological complications in some children. Insofar as it is currently not possible to define an exposure level without risk for the consumer, ANSES recommendsprohibit the consumption of these EOs orally to children under 30 months and children with a history of epilepsy or febrile convulsions, pending more precise toxicological data.
In general, for children and pregnant or breastfeeding women, ANSES advises against the oral consumption of these three essential oils (tea tree, niaouli and cajeput).
Finally, the Agency recalls that food supplements are not drugs and that they should not be consumed as such for therapeutic purposes, since they do not replace conventional medication. She also recommends avoiding consuming several food supplements at the same time, and to report any use of this type of product to your doctor or pharmacist to limit the risk of interactions. To name just one, remember, for example, that supplements containing St. John’s Wort can reduce the effect of an oral contraceptive.