The exact mechanism of action is unknown.<unk>  is a complex mixture of phenols, polycyclic aromatic hydrocarbons (PAHs), and heterocyclic compounds. It is a keratolytic agent, which reduces the growth rate of skin cells and softens the skin's keratin.
Coal tar
Asbestos
Khat
Polychlorinated naphthalene
Vinyl chloride
Dissolvable tobacco
Triphenylchloroethylene
Benzene