Pine oil is an essential oil obtained by the steam distillation of stumps, needles, twigs and cones from a variety of species of pine, particularly Pinus sylvestris. As of 1995, synthetic pine oil was the “biggest single turpentine derivative.” Synthetic pine oils accounted for 90% of sales as of 2000.
The essential oil of the lemon-scented gum mainly consists of citronellal (80%), produced largely in Brazil and China. Unrefined oil from the lemon eucalyptus tree is used in perfumery, and a refined form of this oil is used in insect repellents, especially against mosquitoes. The refined oil’s citronellal content is turned into cis- and trans- isomers of p-menthane-3,8-diol (PMD), a process which occurs naturally as the eucalyptus leaves age. This refined oil, which includes related compounds from the essential corymbia citriodora.