Most oils can be toxic to humans as well. A report of three cases documented gynecomastia in prepubertal boys who were exposed to topical lavender and tea tree oils. The Aromatherapy Trade Council of the UK issued a rebuttal. The Australian Tea Tree Association, a group that promotes the interests of Australian tea tree oil producers, exporters and manufacturers issued a letter that questioned the study and called on the New England Journal of Medicine for a retraction. Another article published by a different research group also documented three cases of gynecomastia in prepubertal boys who were exposed to topical lavender oil.
Despite the sudden burst in popularity, essential oils are not a new thing. The ancient Egyptians were among the first people to use aromatic essential oils, incorporating them into their daily lives. Pure essential oils were incredibly valuable and saved for priests and royals. Ancient books such as the Bible also talk about the use of essential oils. According to the book, Essential Oils for Beginners, the Old and New Testament reference essential oils over two hundred times.