Traditional Pharmacological Uses and Toxicological Evaluation of Thymus vulgaris Essential Oil
DOI:
https://doi.org/10.5281/zenodo.22664589Keywords:
Thymus vulgaris, essential oil, thymol, carvacrol, toxicological safetyAbstract
Background: Thymus vulgaris L. (thyme) essential oil has been used across Mediterranean, Central European and Balkan folk
medicine for respiratory, gastrointestinal and dermatological complaints, and its principal phenolic constituents, thymol and
carvacrol, are now widely traded as antimicrobial and flavouring agents.
Objective: This review synthesizes the published literature on the traditional and ethnopharmacological uses of T. vulgaris essential
oil, its phytochemical variability, its pharmacological activities, and its toxicological and regulatory safety profile, with the aim of
setting the pharmacology against the safety data on comparable, critical terms.
Scope: Ethnobotanical surveys, phytochemical characterization studies, in vitro and in vivo pharmacology (antimicrobial,
antioxidant, anti-inflammatory, spasmolytic and respiratory), acute and repeated-dose toxicity studies, genotoxicity assays,
dermal sensitization case reports and the 2025 EFSA feed additive safety opinion on thyme oil are reviewed and cross-referenced.
Conclusions: Thyme oil's traditional respiratory and antimicrobial uses are supported by a reasonably coherent mechanistic and
toxicological evidence base: acute oral toxicity is low, genotoxicity data on thymol and carvacrol are reassuring, and regulatory
review has judged the oil safe at proposed dietary and feed use levels. Chemotype heterogeneity across studies, a scarcity of
long-duration whole-oil toxicity data, and a real dermal sensitization risk remain the principal gaps warranting further
chemotype-standardized research.
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