[Olfactory adaptation as a factor limiting the warning role of odors].

Threshold concentrations of olfactory sensation of odorants change due to adaptation to polluted atmosphere. The study was aimed at determination of trimethylamine and n-butanol threshold concentrations of olfactory sensation under standard laboratory conditions. The results were analysed from two viewpoints: the role of odour as a warning against chemical hazard, a possibility of using the shift of sensation threshold of appropriately selected reference standards as a measure of discomfort created by odours in working environment.