The ototoxic effects of toluene (108883) were explored in this review. The physical properties along with the biological absorption, distribution, and metabolism of toluene were described and discussed. Evaluations of cases of solvent abuse involving toluene provided the initial recognition of possible ototoxic effects of this agent. These reports documented balance disorders and hearing impairment in toluene abusers. Animal experiments have confirmed these findings and suggested that the ototoxic effects observed may have resulted from biochemical mechanisms such as stimulation of the central vestibulo/oculomotor pathways due to an effect of solvent molecules on cellular ionic transport within the vestibulo/cerebellum and interference with cerebellar gamma- aminobutyric-acid transmission. Incidents of human exposure have been reported to result in alterations in spontaneous vestibular functions and hearing as well as feelings of dizziness, drunkenness and lightheadedness. Additional animal studies have indicated that toluene exposure may induce permanent and progressive damage to the auditory system of the rat. The degree of ototoxicity in the rat was found to be dependent on the concentration, exposure time, and daily duration of exposure. Interactions between toluene and other factors such as age and genotype or other concurrent exposures such as ethanol (64175), acetylsalicylic-acid (530756), n-hexane (110543), or noise were discussed. Studies examining the effects of occupational toluene exposure were reviewed.