The products of coal tar distillation consist of a complex mixture of mono- and polycyclic aromatic hydrocarbons and resin (Betts WD, Tar and pitch. In: Kirk-Othmer encyclopedia of chemical technology, 5th edn. Wiley, New York, 1997). By the 1990s, coal tar became the main source of anticorrosive coatings and wood preservatives. Some authors reported very high death rates from scrotal cancer among coal tar distillers, and a French study showed a significant increase in the incidence of oral cavity and pharyngeal cancer. Epidemiological studies are consistent that occupational exposure during tar distillation is carcinogenic to humans and causes lung cancer. Its most representative urinary metabolite is 1-hydroxypyrene.