The tar is a derivative coal of black color. By-product of the Distillation of the coal during the manufacture of the coke, it is very viscous, even solid (tar pitch). In the language running, one often confuses it with the Bitume of oil origin . This confusion is due to the invention of the Tarmacadam , ancestor of the road coatings which was manufactured at the origin with tar ( tar in English). The tarmacadam is him even confused with the Macadam which is only one technique of macadamization without tar nor bituminizes; the term gave “tarmac”, which indicates a landing strip of plane. Nowadays, the tar is usually not employed any more in road engineering. One uses it only when one wants to profit from his resistance to the Hydrocarbure S, for example in the service stations (the bitumen, of oil origin, is soluble in hydrocarbons).

The tar is also a substance present in the smoke of the Tabac: its name is derived from the translation of the English tar , itself an acronym of total aerosol residue . It is composed of hundreds of chemical substances, of which several are regarded as carcinogenic or potentially dangerous. Among those, one finds in particular aromatic hydrocarbons polycyclic (HAP), aromatic amines and compounds inorganic.

Composed of the tar

External bonds

Beats-smg: Tribe