Larger production volume and natural sources of monohydroxybenzene, generically known as phenol, make exposure likely. Occupational and environmental exposure to phenol is largely restricted to source dominated areas, however. Based on monitoring data, ambient levels of phenol are extremely low compared with the present TLV (threshold limit value) of 5 ppm (19 mg/cu.m.). The STEL (short-term exposure level) for phenol is 10 ppm (38 mg/cu.m.). The estimated half-life of phenol is 0.5 day, and less than 1 minute in polluted atmospheres. The odor recognition threshold of phenol is 0.05 ppm (0.19 mg/cu.m.), a level far below the levels where toxic effects have been reported. Phenol is absorbed by animals and humans after oral, inhalation, or dermal exposure. Muscle weakness, convulsions, and coma are the predominant symptoms after exposure to lethal concentrations. After absorption, exogenous phenol is metabolized principally by the liver, and excretion occurs mainly via urine.

Includes bibliographical references (pages 32-37). "January 1986." "EPA 600/8-86-003F." Microfiche.