Nasal irritation and odor from homologous series of chemicals
To assess the independent contribution of nasal irritation (pungency) and odor to the detection of nonreactive volatile organic compounds (VOCs), we measured nasal detection thresholds in subjects lacking olfaction (anosmics) and in matched controls (normosmics). Homologous alcohols, acetates, and ketones served as stimuli. Most substances evoked irritation (i.e., were detected by the anosmics). Both odor and pungency thresholds decreased with carbon chain length. A robust linear correlation, with slope close to one, between nasal pungency and saturated vapor concentration for all stimuli together suggests that irritation from nonreactive VOCs relies on a broadly tuned physicochemical interaction with a susceptible biophase.