A Technique for Comparing the Threshold Concentrations for Olfactory, Trigeminal, and Ocular Irritations

Abstract

A new technique is described for comparing the threshold concentrations that will produce olfactory, trigeminal, and ocular irritation when odorous irritants are exposed to the nose and eyes. It depends on the reduction of concentration of an odorous irritant in air, when the air is passed through an adsorbent. Of the four odorous irritants used in this investigation, three, viz. acetic anhydride, formaldehyde and triethylamine, first irritated the eye, then became perceptible to smell and finally irritated the nasal membranes as their concentration was gradually increased. The order of sensitivity of the three senses towards them was in each case: eye irritation > smell > nasal irritation. It was not found possible to separate the three sensations when ammonia was the odorous irritant, all three seeming to appear and to disappear together.