Pine tar along with many other ingredients due to a lack of proof of their effectiveness. Some pine tar products contain creosote, a probable carcinogen. Creosote potentially may be produced when the pine wood is heated up to high temperatures in the creation of pine tar. Pine tar is also used in veterinary medicine as an expectorant and an antiseptic in chronic skin conditions. Pine tar Pine tar is a sticky material produced by the high temperature carbonization of pine wood in anoxic conditions (dry distillation or destructive distillation). The wood is rapidly decomposed by applying heat and pressure in a closed
Wood preservation resistance of wood species is always based on the heartwood (or "truewood"). The sapwood of all timber species should be considered to be non-durable without preservative treatment. Tung oil has been used for hundreds of years in China, where it was used as a preservative for wood ships. The oil penetrates the wood, and then hardens to form an impermeable hydrophobic layer up to 5 mm into the wood. As a preservative it is effective for exterior work above and below ground, but the thin layer makes it less useful in practice. It is not available as a pressure treatment.