Its used for staining Sheds and Fences, and is a good wood-preserver that stops untreated wood from rotting and absorbing water...

creosote is used to protect wood (such as the garden fence) from the elements - it is commonly used as a wood preservative for use against wood destroying insects and wood rotting fungi.

It's one of the oils used in making treated wood for decks, fences etc and also used in outdoor paints... Yes in a concentrated form it's dangerous, also burning the treated wood can cause damage to your eyes and lungs, a lot of people will break out in a rash just by touching the wood...

"Creosote is the name used for a variety of products: wood creosote, coal tar creosote, coal tar, coal tar pitch, and coal tar pitch volatiles. These products are mixtures of many chemicals such as polycyclic aromatic hydrocarbons (PAHs), phenol, cresols created by high temperature treatment of beech and other woods, coal, or from the resin of the Creosote bush. " "Wood creosote is a colorless to yellowish greasy liquid with a smoky odor and burned taste. Wood creosote has been used as a disinfectant, a laxative, and a cough treatment, but these have mostly been replaced by newer medicines. The popular Japanese anti-diarrheal Seirogan has 133mg creosote (from beech, maple or oak wood) per adult dose as its primary ingredient" "Coal tar creosote is a thick, oily liquid typically amber to black in color. Coal tar and coal tar pitch are usually thick, black, or dark-brown liquids or semi-solids, with a smoky odor. Coal tar products are used in medicines to treat diseases such as psoriasis, and also as animal and bird repellents, insecticides, animal dips, and fungicides. Coal tar creosote is the most widely used wood preservative in the United States. Virtually all wooden railroad ties and telephone poles in use are treated with creosote to retard rotting. Coal tar, coal tar pitch (pitch), and coal tar pitch volatiles are used for roofing, road paving, aluminum smelting, and coking." "Eating food or drinking water contaminated with high levels of creosotes may cause a burning in the mouth and throat, and stomach pains. Brief direct contact with large amounts of coal tar creosote may result in a rash or severe irritation of the skin, chemical burns of the surfaces of the eyes, convulsions and mental confusion, kidney or liver problems, unconsciousness, and even death. Longer direct skin contact with low levels of creosote mixtures or their vapors can result in increased light sensitivity, damage to the cornea, and skin damage. Longer exposure to creosote vapors can cause irritation of the respiratory tract. Long-term exposure to low levels of creosote, especially direct contact with the skin during wood treatment or manufacture of coal tar creosote-treated products has resulted in skin cancer and cancer of the scrotum. Cancer of the scrotum in chimney sweeps has been associated with long-term skin exposure to soot and coal tar creosotes. Animal studies have also shown skin cancer from skin exposure to coal tar products. The International Agency for Research on Cancer (IARC) has determined that coal tar is carcinogenic to humans and that creosote is probably carcinogenic to humans. The United States Environmental Protection Agency has determined that coal tar creosote is a probable human carcinogen." "In 2003 the European Union banned creosote for amateur and unlicensed professional use, due to concerns over these health effects, noting that recent research had shown that the risk of skin cancer had perhaps been underestimated previously." Source and further information: http://en.wikipedia.org/wiki/Creosote_oil

It used to be very common to use it for preserving posts and wood that came in contact with the ground or in water like piers. Then they came up with the green pressure treated wood instead because Creosote was just too dangerous and toxic. It got into the ground water and was a skin irritant. But it is still around in every wood burning chimney as the residue from burning wood. It coats the inside of the pipe and maybe even blocking up the pipe when it sort of crystallizes. It's one of the leading causes of chimney fires, when you don't clean it out often enough and the flames heat it up and it catches on fire. Chimney sweeps who clean them out have often gotten scrotum cancer from the creosote if they don't take precautions to keep it from contacting their skin.