OpenTox Virtual Conference 2021 Session 6
Determination of safe recommended doses for essential oils consumed as food supplements
Isabelle Sartori Tamburlin* PhD, Elise Roux1, Marion Feuillée2, Julie Labbé PhD, Yannick Aussaguès, Fatima Ezzahra El Fadle PharmD, Françoise Fraboul3 DMV, Guy Bouvier PhD
1) Present address: LVMH Recherche, 45800 Saint Jean de Braye, France; 2) Present address: Sanofi Winthrop Industrie, 94700 Maisons-Alfort, France; 3) Present address: ProTox Consulting, 82000 Montauban, France
The wish to benefit from natural solutions to cultivate well-being as well as to treat daily ailments has led to a growing interest in herbal food supplements, and among them, essential oils. Published recommended doses for their use are scarce and mostly based on traditional use or clinical practice. On the other hand, the introduction of a regulatory framework for herbal products used as food supplements led the concept of substances to be monitored. In that context, we propose to assess the safety of orally administered essential oils using a constituent-by-constituent approach, assuming additivity rather than synergy between constituents. First of all, the genotoxic potential of each constituent is evaluated based on literature data or QSAR analyses. Genotoxic chemicals are evaluated according to the methodology provided in the ICHM7 guideline for mutagenic impurities. For non-genotoxic constituents, a Toxicological Reference Value (TRV) is searched for in recognized databases, or in clinical studies. In the absence of human data, in decreasing preference order, TRVs are derived from appropriate NOAELs in animal toxicity studies by applying adequate safety factors, from reading across analyses when possible, or by applying the TTC values associated with Cramer classes.
The daily dose recommended for the EO is considered safe when the Margins of safety (MoS) calculated for each of its constituents, i.e. the ratio between the TRV and the systemic exposure dose (SED), are all equal to or higher than 1.
In conclusion, this methodology was proven robust to establish safe recommended daily doses for Essential Oils used orally as food supplements, generally consistent with those publicly available. and avoiding unnecessary animal testing.