A study of the risk of neurological disorders among aluminum (7429905) workers was conducted. The cohort consisted of 63 males, mean age 54.0 years (yr), employed in the potroom of an aluminum smelter. A series of case reports had indicated that 25 workers in the potroom of the smelter had previously developed symptoms of neurological problems. The controls consisted of 37 males, mean age 53.9yr, employed elsewhere in the facility. The subjects completed a neurological symptom questionnaire. They were given a physical examination that focused on neurological signs. The subjects were then evaluated on a neurological test battery that evaluated hand and leg tremors and postural stability and measured reaction time and verbal intelligence. The potroom workers reported higher prevalences of 14 of 15 symptoms on the neurological symptom questionnaire than the controls. Only three symptoms were reported at a significantly higher frequency than by the controls: incoordination, difficulty buttoning, and depression. The increased prevalence of these symptoms represented odds ratios of 10.6, 6.2, and 6.2, respectively. No significant differences between the potroom workers and the controls were seen in the neurological examination, tremor tests, or reaction time or verbal intelligence tests. Inconsistent changes in sway radius were seen in the postural stability test; however, the intergroup differences were not statistically significant. The authors conclude that the objective measures of neurological function obtained in this study provide little support for the view that the previously reported symptoms can be related to work in the potroom. The increase in some reported symptoms, however, could be an indicator of early, subtle neurological changes. Because of limitations in the study design, such as the possibility of information bias in the potroom workers, these findings should be interpreted cautiously.