Fragrant plant oil whose active constituents are found in the leaves and in the oil obtained from them. The oil has benefits for skin, but is also a potent skin sensitizer due to its chemical components. Truly a mixed bag, this oil, like rosemary oil, has benefits and risks. Low amounts of eucalyptus oil do not seem to pose a risk of sensitivity in the general population, but its fragrance components are known sensitizers.
References for this information:
Basic and Clinical Pharmacology and Toxicology, June 2006, pages 575-581
Asian Pacific Journal of Tropical Biomedicine, August 2015, pages 601-611