Creosote name is derived . The two main kinds recognized in industry are coal-tar creosote and wood-tar creosote. The coal-tar variety, having stronger and more toxic properties, has chiefly been used as a preservative for wood; coal-tar creosote was also formerly used as an escharotic, to burn malignant skin tissue, and in dentistry, to prevent necrosis, before its carcinogenic properties became known. The wood-tar variety has been used for meat preservation, ship treatment, and such medical purposes as an anaesthetic, antiseptic, astringent, expectorant, and laxative, though these have mostly been replaced by modern formulations. Varieties of creosote have also been made
Cedar oil was laid in natrum or natron—a fixed alkali—for the prescribed period, after which the cedarwood oil, which had dissolved the soft organs, was released; and the body, its flesh dissolved by the natron, was reduced to preserved skin and bones. Until the development of synthetic immersion oil in the 1940s, cedarwood oil was widely used for the oil immersion objective in light microscopy. It is still sometimes also used to clarify emeralds. Cedar leaf oil from "Cedrus atlantica" does not contain thujone. Cedarwood oil is a mixture of organic compounds considered generally safe by the FDA as a food additive