Candidate physiological measures of annoyance from airborne chemicals

Annoyance due to short-term exposure to airborne chemicals is a key factor in modern environmental research. Unpleasant odors or those that are believed harmful can annoy us. Since annoyance is modulated by the psychological and physiological states of the exposed persons, it is essential that we understand how these factors interact with environmental stimuli to yield a given level of this response. A potentially fruitful approach in this effort may be to treat annoyance as an emotion induced by the odor, and possibly irritation, resulting from chemical exposures. In this way, methods applied to assess induced emotions will likely be of value in elucidating annoyance. A rationale is presented for use of the startle reflex to elucidate the motor component of annoyance, which is manifest as a redirecting of attention towards the annoying odor (or irritant). Although evidence supporting the use of breathing changes to assess the vegetative component of annoyance is somewhat more scattered and indirect, this approach seems likely to be the most fruitful for future research. Experiments to enhance our understanding of annoyance using these two non-verbal end-points are outlined.