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**41**

**Chapter 3**

**Abstract**

disrupting potential

**1. Introduction**

mercially available [3] (**Table 1**).

Safety Profile of Essential Oils

*Oliviu Vostinaru, Simona Codruta Heghes and Lorena Filip*

Essential oils are complex mixtures of terpenes and phenylpropanoid compounds, present in multiple species of aromatic plants. They are extensively used in food and cosmetic industries in order to give flavor to food and drinks or as natural fragrances. Moreover, several compounds present in essential oils are important for the pharmaceutical industry due to their antioxidant, antimicrobial, anxiolytic or spasmolytic effects. Although many essential oils are generally recognized as safe, a series of adverse reactions have been reported after their use either by internal or external routes. The aim of this chapter is to increase the awareness of healthcare professionals concerning possible safety issues of essential oils. Common adverse effects of essential oils like sensitization and dermatitis but also more severe phenomena like neurotoxicity will be presented in detail, concerning their epidemiology, mechanism and clinical significance. A thorough understanding of the safety profile of essential oils is necessary for healthcare and food industry professionals in order to maximize their beneficial effects while minimizing the risk for the users.

**Keywords:** essential oils, terpenes, sensitization, neurological toxicity, endocrine

Essential oils (EOs) are complex mixtures of aromatic terpenes (monoterpenes and sesquiterpenes) and other aromatic or aliphatic compounds, formed as secondary metabolites in specialized secretory tissues of aromatic plants [1]. Various parts of the aromatic plants (leaves, flowers, fruits, roots, bark) could be used for essential oil extraction by multiple techniques including steam distillation, solvent extraction or supercritical fluid extraction [2]. A verified botanical origin (chemical composition) and protection against contamination and oxidative degradation provided by adequate recipients are key factors influencing essential oils quality. Essential oils from peppermint, lavender, jasmine or ylang-ylang have been used from Antiquity in European and Asian traditional medicine for the prevention and treatment of several diseases but also for food flavoring. Nowadays, over 3000 compounds have been identified in EOs and more than 300 essential oils are com-

Essential oils are extensively used as food flavors, as fragrances in cosmetic industry but also, a para-medicinal use like aromatherapy has become increasingly popular in the last decades (**Figure 1**). Moreover, due to a complex chemical composition, they are capable to interact with multiple pharmacological targets (receptors, ion channels or enzymes), being studied with promising results for the development of new drug candidates. Some essential oils like peppermint oil are already used in clinical settings for the treatment of functional dyspepsia or irritable bowel
