Aromatic hydrocarbons, oral administration

Benz [a] anthracene alone is not regulated however, all polycyclic aromatic hydrocarbons or volatile coal tar products together are regulated. The World Health Organization has established 0.2 pgH as the limit for aromatic hydrocarbons in a domestic water supply. The US Occupational Safety and Health Administration limit in workplace air (coal tar volatiles) is 0.2 mg m The US Environmental Protection Agency weight-of-evidence classification for benz [a] anthracene is B2, a probable human carcinogen, for both oral and inhalation exposure based on adequate animal evidence and no human evidence. 

The first investigators noted the concurrent excretion of phenols, phenol sulfatc.s, polyhydroxybcnzcncs and their glucuronidcs when mercapturic acid formation was induced in dogs by the oral administration of aromatic hydrocarbons or their monohalogen derivatives. Subsequent work demonstrated that a variety of species form mercapturic acids. Principally mammals have been studied but also some birds and insects. Recent review s on mercapturic acids include those of Williams (1959), Boyland (1962), Maw (I960), and Parke (1968). 

Hydrocarbons in the aromatic EC>lg-EC35 fraction may be absorbed to varying extents following inhalation, oral, or dermal exposure, depending on the lipophilicity and molecular size of the compound and the vehicle of administration, as indicated by studies of humans exposed to workplace-air complex mixtures containing PAHs (i.e., hydrocarbons with more than two 5- or 6-carbon aromatic... 

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