The aims of this study are to verify the potential lead damage on olfactory function and to identify early effects due to lead exposure. Our diagnostic evaluation included: (i) questionnaire to collect data about work and clinical history, (ii) olfactory evaluation: threshold test (Single-Starcaise) and identification/discrimination test (Wright). Lead exposure was evaluated by air sampling and biological monitoring (PbB, lead in blood). A sample of 18 exposed workers (mean age: 41.3 +/- 7.8; years exposure: 8.38 +/- 6) and of 39 controls (mean age: 41.9 +/- 9.7) were evaluated. The comparison between the threshold test of two groups confirmed a worse olfactory function in exposed (-4.97 log(10)vol/vol) compared to controls (-6.37 log(10)vol/vol), while the Wright test didn't show any significant correlation. The study didn't find a significant association between individual PbB levels and the threshold test. Knowledge of the effect of chronic occupational exposure to industrial chemicals on olfactory function is largely incomplete, but supports the hypothesis that olfactory neuroepithelium is susceptible to environmental exposures to chemicals. Occupational-related olfactory impairment is usually sub-clinical, and can be only detected using adeguate quantitative olfactory function testing procedures for quality research in this field.