The oils are blended in a FDA inspected plant in the United States under stringent temperature, sanitary and quality control conditions in exact ratios according to our formula. The Eucalyptus Oil comes from Australia. Of the 600 varieties of Eucalyptus plants there is only one that contains the highest concentration of active ingredient (cineole). That is the Blue Mallee Eucalyptus (E. Polybractea). It is considered the most esteem in healing and is the only kind we use. The other four ingredients are of the highest quality and come from the best sources from around the world.