Safety and possible risks of tea tree oil from a toxicological perspective
Sonia Sanajou, Rana Ülker Özkan, Pınar Erkekoğlu, Gözde Girgin, Terken BaydarTea tree oil (TTO) is a sophisticated essential oil extracted from the Melaleuca alternifolia plant. It comprises around 1,000 components with a significant presence of monoterpenes and their alcohols. Terpinen-4-ol, the monoterpene that makes up 30% to 48% of TTO essential oil, is the main factor responsible for its strong antibacterial properties. TTO has been extensively used in skin care products to treat many problems, including acne, eczema, and dandruff. TTO is included in products used by children and adults. Nevertheless, the reliability of TTO in cosmetic and dermatological or derma cosmetic formulations is contingent upon numerous influential aspects, underscoring the pivotal significance of formulation and production procedures. TTO can be taken orally, topically, or ocularly. However, it is important to exercise caution, as high levels of TTO may cause phytotoxic effects and result in negative consequences such as contact allergy, inflammation, irritation, and dermatitis. Though natural, this essential oil can be harmful if not used correctly, considering factors like the route of application, exposure dose, and poor-quality contents. This review thoroughly examines the negative consequences, considerations for safety, and regulatory factors related to the usage of TTO. The study emphasizes the importance of conducting thorough research to better understand the safe use of essential oils, especially TTO. It also calls for a full assessment of the possible negative effects on vulnerable populations. Given the increasing demand for products containing TTO, it is crucial to conduct ongoing research to improve recommendations and ensure the informed and safe use of this precious essential oil.