Table 1.

Characteristics of the investigated odorous substances.

Substance	Odour Type	Vapour Pressure (hPa)	Olfactory Threshold in the Gas Phase (ppm)
Toluene	Pleasant and characteristic	29	0.33–2.9
Acetone	Fruity, sweet	233	13–100
Triethylamine	Fish, pungent	72	0.000032–0.48
Formaldehyde	Pungent, stifling	1.4	0.5–1
Butyric acid	Rancid, odour of sweat	0.6	0.00019–0.001
α-Pinene	Pine, resinous	5	0.018