Шағала жапырағынан алынған май: қасиеттері мен қауіптері

Essential oil derived from leaves
essential oil isolated from the leaves of the tea tree, Melaleuca alternifolia

Tea tree oil, also known as melaleuca oil, is an essential oil with a fresh, camphoraceous odor and a colour that ranges from pale yellow to nearly colourless and clear. It is derived from the leaves of the tea tree, Melaleuca alternifolia, native to southeast Queensland and the northeast coast of New South Wales, Australia. The oil comprises many constituent chemicals, and its composition changes if it is exposed to air and oxidizes. Commercial use of tea tree oil began in the 1920s, pioneered by the entrepreneur Arthur Penfold. As a traditional medicine, it is typically used as a topical medication in low concentrations for the treatment of skin conditions, but little evidence exists of clinical efficacy. Tea tree oil is neither a patented product nor an approved drug in the United States, It is poisonous if consumed by mouth and is unsafe for children. insufficient evidence exists to support any of these claims due to the limited quality of research. According to the Committee on Herbal Medicinal Products (CHMP) of the European Medicines Agency, traditional usage suggests that tea tree oil is a possible treatment for "small, superficial wounds, insect bites, and small boils" and that it may reduce itching in minor cases of athlete's foot. The CHMP states that tea tree oil products should not be used on people under 12 years of age. Tea tree oil is not recommended for treating nail fungus because it is yet to be proven effective, It is not recommended for treating head lice in children because its effectiveness and safety have not been established and it could cause skin irritation or allergic reactions. There is no good evidence tea tree oil is an effective treatment for demodex mite infestations.

Tea tree oil is highly toxic when ingested orally. It may cause drowsiness, confusion, hallucinations, coma, unsteadiness, weakness, vomiting, diarrhea, nausea, blood cell abnormalities, and severe rashes. It should be kept away from pets and children. Application of tea tree oil to the skin can cause an allergic reaction, Adverse effects include skin irritation, allergic contact dermatitis, systemic contact dermatitis, linear immunoglobulin A disease, erythema multiforme like reactions, and systemic hypersensitivity reactions. Allergic reactions may be due to the various oxidation products that are formed by exposure of the oil to light and air. Consequently, oxidized tea tree oil should not be used. In Australia, tea tree oil is one of the many essential oils causing poisoning, mostly of children. From 2014 to 2018, 749 cases were reported in New South Wales, accounting for 17% of essential oil poisoning incidents.

Tea tree oil potentially poses a risk for causing abnormal breast enlargement in men and prepubertal children. A 2018 study by the National Institute of Environmental Health Sciences found four of the constituent chemicals (eucalyptol, 4 terpineol, dipentene, and alpha terpineol) are endocrine disruptors, raising concerns of potential environmental health impact from the oil.

In dogs and cats, death or transient signs of toxicity (lasting two to three days), such as lethargy, weakness, incoordination, and muscle tremors, have been reported after external application at high doses. As a test of toxicity by oral intake, the median lethal dose (LD50) in rats is 1.9–2.4 ml/kg. Tea tree oil products contain various phytochemicals, among which terpinen 4 ol is the major component. The commercial tea tree oil industry originated in the 1920s when Australian chemist Arthur Penfold investigated the business potential of a number of native extracted oils; he reported that tea tree oil had promise, as it exhibited antiseptic properties. Tea tree oil was first extracted from Melaleuca alternifolia in Australia, and this species remains the most important commercially. In the 1970s and 1980s, commercial plantations began to produce large quantities of tea tree oil from M. alternifolia. Many of these plantations are located in New South Wales.). Similar oils can also be produced by water distillation from Melaleuca linariifolia and Melaleuca dissitiflora. Whereas the availability and nonproprietary nature of tea tree oil would make it – if proved effective – particularly well suited to a disease such as scabies that affects poor people disproportionately, those same characteristics diminish corporate interest in its development and validation.