24 solvent abusers (mean age 23 +/- 4.4 years +/- SD) were studied in hospital. They reported using substances containing a mean of 425 +/- 366 mg of toluene per day for 6.3 +/- 3.9 years. There was no laboratory evidence of under-nutrition. No withdrawal symptoms were observed. Marked impairment was observed in neurological and neuropsychological test performances in 65% of the sample. Cerebellar symptoms were particularly prominent. The impairment was significantly correlated with CT scan measurements of the cerebellum, ventricles and cortical sulci, all of which abnormal in comparison to age-matched controls. CSF abnormalities were elevated C1-, low PO2 and very low anion gap. The duration of abuse was only weakly correlated with neurological scores. After 2 weeks of abstinence, several liver function tests which were abnormal on admission had recovered, but only minimal changes in the CNS symptoms were observed.