To assess the effects of low-level organic solvent exposure on olfactory function, a cross-sectional study in paint manufacturing workers was undertaken. Workers in two paint manufacturing facilities (N = 187) were tested using the University of Pennsylvania Smell Identification Test (UPSIT), a standardized, quantitative test of olfactory function. Industrial hygiene air samples over the past 13-15 years revealed that average solvent exposures in these plants were 2-40% of the existing threshold limit values for the three chemicals measured. Stratification by smoking status revealed evidence of dose-related decrements in olfactory function (p = .01) only in non-smokers. Furthermore, those nonsmoking workers in the highest exposure category had UPSIT scores below the fifth percentile for their age. These results suggest that solvents may cause nervous system dysfunction at lower levels than previously suspected, and that the olfactory system may be a critical target organ for the neurotoxic effects of solvents and other chemicals.