Chemicals in Laboratory Room Air Stimulate Olfactory Neurons of Female Bombyx mori

Laboratory air contained odorants that elicited electrophysiological responses in female Bombyx mori antennae. Air entrainments on charcoal filters, extracted with CS2 and subsequently with acetone, were analyzed by coupled gas chromatography (GC)–electroantennogram (EAG) as well as by GC–mass spectrometry. The CS2 extract contained 12 EAG-active peaks from which benzaldehyde, octanal, limonene, 1,8-cineol, methyl benzoate, nonanal, decanal and geranyl acetone were identified. In the acetone extract we identified eight EAG-active peaks as phenol, nonanal, 2-ethylhexanoic acid, octanoic acid, benzoic acid, nonanoic acid, decanoic acid and dimethyl phthalate. The concentrations of benzoic acid and benzaldehyde present in laboratory air were determined. The origin of the substances and importance of such odorants in laboratory air for the interpretation of physiological experiments on the olfactory system is discussed.