1,8-Cineole, commonly known as Eucalyptol, is a colourless to light yellow liquid with a distinctive camphoraceous spicy odour. It constitutes up to 90% of eucalyptus oil, from which it derives its common name. 1,8-Cineole is also widely found in the foliage of various other aromatic plants, including camphor laurel, bay leaves, tea tree, mugwort, sweet basil, wormwood, rosemary, and sage.