Botanical Adulterants Prevention Program Releases Tea Tree Oil Laboratory Guidance Document

In September, the Laboratory Guidance Document (LGD) on methods to authenticate and detect adulteration of the essential oil made from the leaves of tea tree (Melaleuca alternifolia and M. linariifolia, Myrtaceae) was published. The issues surrounding tea tree oil adulteration, mainly with lower-cost materials obtained during the distillation process of camphor (Cinnamomum camphora, Lauraceae), eucalyptus (Eucalyptus globulus and other Eucalyptus spp., Myrtaceae), and pine (Pinus spp., Pinaceae) essential oils, or by adding pure chemical compounds, e.g., terpinen-4-ol obtained after acid-catalyzed conversion of sabinene, have been previously summarized in a bulletin on the topic. The new LGD has an extensive review of the chemistry of tea tree oil and its adulterants, and an evaluation of 23 test methods for their appropriateness to detect tea tree oil adulteration. It has been written by Stefan Gafner, PhD, chief science officer of the American Botanical Council (ABC), and Ashley Dowell, manager of the Analytical Research Laboratory at Southern Cross University (East Lismore, NSW, Australia) and expert in tea tree oil analysis. The tea tree oil LGD is the 6th in this series and the 45th peer-reviewed publication published by the Botanical Adulterants Prevention Program.