Seirogan ingredient. That ingredient in the West may otherwise go by such names as "wood creosote", "beechwood creosote", or "liquid pitch oil", and should be distinguished from industrial "coal-tar creosote". To emphasize the distinction, wood creosote in Japan is sometimes called by such names as and minor variants thereof. The wood creosote is blended with two or more recognized in for their antiseptic and other effects, but the additional ingredients used are different among manufacturers (See under #Chemical composition for a sampling of formulas). Some quarters (perhaps kanpō medicine practitioners and others) insist however that "Seirogan is not strictly speaking kanpō
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