An Analysis of Nasal Irritation Thresholds Using a New Solvation Equation

In Experiment 1, subjects sought to localize the nostril stimulated, left or right, in tests with nine esters (acetates, propionates, and butyrates) at concentrations meant to trigger chemesthesis (pungency, irritation). The task produced psychometric functions for chemesthetic detection unconfounded by olfactory sensations. The functions indicated a sharp transition from no detection to perfect detection, rather uniform across the esters, which themselves varied in potency by two log units. The correlation between the thresholds for the eight materials that yielded thresholds and predictions from a published linear free energy relationship (LFER) equaled 0.99. In Experiment 2, amplitude of the negative mucosal potential (NMP) was recorded from the septum. The resulting functions also increased with concentration sharply. Against a criterion amplitude of the NMP, thresholds measured in the first experiment (and predictions from the LFER) correlated 0.99. The NMP seems to offer an adequate objective measure of sensory irritation. The LFER, although effective predictively, could stand to have a parameter to anticipate that molecules beyond a certain size fail to trigger irritation. In the present case, a cut-off of chemesthetic potency occurred between butyl butyrate and hexyl butyrate for the group of subjects, with some variation of the boundary among individuals.

show abstract

“…VOCs led to creation of a QSAR in the form of a linear free energy relationship (LFER) [23][24][25]:…”

Section: Quantitative Structure-activity Relationship (Qsar)mentioning

confidence: 99%

Chemesthesis from volatile organic compounds: Psychophysical and neural responses

Cain

Lee

Wise

et al. 2006

Physiology & Behavior

Self Cite

View full text Add to dashboard Cite

show abstract

“…In this regard, studies of quantitative structure-activity relationships (QSARs) for the odor potency of single chemicals (including the four compounds mentioned) have indicated that, in addition to parameters governing the transfer of the stimulus from the vapor phase to the olfactory receptor biophase, parameters involving molecular size and chemical functionality play a significant role in olfactory potency [2,3]. In contrast, the chemesthetic (i.e., nasal pungency and eye irritation) potency of largely the same single chemicals rests almost exclusively on transfer processes [1,[4][5][6], at least until a critical molecular size is reached where chemesthesis fades away (we had called this a "cut-off" effect) [14].…”

Section: Introductionmentioning

confidence: 99%

Odor detection of single chemicals and binary mixtures

Cometto‐Muñiz

Cain

Abraham

2005

Behavioural Brain Research

View full text Add to dashboard Cite

The investigation explored the olfactory detectability of two chemically and structurally similar esters, ethyl propanoate and ethyl heptanoate, presented singly and in mixtures. Initially, we measured concentration-detection (i.e., psychometric) functions for the odor of ethyl propanoate and ethyl heptanoate presented singly. Using this information, we prepared binary mixtures of the two chemicals in varying complementary proportions and, also, selected concentrations of the single compounds, such that, if a rule of response-addition (i.e., independence of detection) were to hold, the stimuli (mixed and single) should approximate equal detection. Next, we measured the actual detectability of these stimuli within the same experiment. The results were analyzed in terms of response-addition (or -additivity) and of dose-addition (oradditivity). The outcome revealed that at low levels of detectability the mixtures approximate response-addition, that is, independence of detection, whereas at high levels of detectability they approximate dose-addition. In the light of previous findings for the olfactory detection of the more dissimilar chemical pairs 1-butanol/2-heptanone and butyl acetate/toluene, we conclude that the described outcome generalizes across a variety of chemical pairs.

show abstract

“…Anosmic subjects have consistently yielded thresholds with little intersubject variability, far less than that shown by normosmics for odor detection (Cometto-Muñiz and Cain 1990, Cometto-Muñiz and Cain 1991, Cometto-Muñiz and Cain 1993, Cometto-Muñiz and Cain 1994b, ComettoMuñiz et al 1997a, Cometto-Muñiz et al 1997b. The data from small samples of anosmics per study over a number of studies have permitted derivation of a physicochemical model to predict thresholds for pungency with high certainty (Abraham et al 1996). Despite the success of the studies of anosmics, it remains of interest to specify odor thresholds and pungency thresholds in the same individuals (viz., normosmics).…”

Section: Introductionmentioning

confidence: 99%

“…Since physicochemical properties in such series change regularly, these substances provide a "benchmark unit" (i.e., carbon chainlength) against which to measure potency of odor, nasal pungency, and eye irritation, another chemesthetic response to VOCs Cain 1991, Cometto-Muñiz andCain 1995b). A solvation equation that combines four physicochemical parameters has served well to describe and predict the nasal pungecny potency, for single-sniff exposures, of more than 40 such VOCs of various chemical functionalities (Abraham et al 1996, Cometto-Muñiz et al 1997a). …”

Section: Introductionmentioning

confidence: 99%

Trigeminal and olfactory sensitivity: comparison of modalities and methods of measurement

1998

International Archives of Occupational and Environmental Health

107

View full text Add to dashboard Cite

Objective: The principal objective was to chart sensitivity for human nasal irritation by alternative psychophysical methods, a common detection procedure vs. a nasal lateralization procedure that required the subject to indicate whether a vapor had stimulated the left or right nostril. This objective relates to the broader issues: a) whether subjects with normal olfaction (normosmics) can yield, through novel methodology, an index of sensitivity to nasal irritation comparable to that obtained from subjects without olfaction (anosmics) and b) whether both types of subjects have similar irritation sensitivity in general. This study sought to gauge interconvertability both between types of subjects and between modes of stimulus presentation, for irritative and, where appropriate, olfactory stimulation.Methods: Static dilution series of four n-aliphatic alcohols, chosen to represent volatile organic compounds (VOCs), provided the source of calibrated olfactory and irritative vapors, emitted from their squeezable containers into the nose or eye by either a mechanical device or by hand.Standard psychophysical methodology (forced-choice; ascending strength of stimulation) served to chart detection thresholds for irritation and odor and an analogous procedure served to chart the threshold for localization of stimulation.Results: Within the limits of resolution, detection thresholds and nasal localization thresholds yielded comparable indices of the potency of the VOCs to evoke nasal irritation. The thresholds agreed well with those for detection of eye irritation, though only the eyes proved able to detect irritation from 1-octanol. The method of emitting the stimulus had little material effect on measures of either irritative or olfactory detection. Conclusions:The threshold for nasal localization offers a suitable way to measure nasal irritation in normosmic persons. Olfactory stimulation does not interfere with the measure since subjects cannot localize on that basis. Anosmic and normosmic persons have comparable sensitivity to nasal and ocular irritation. If anosmic persons have any lower sensitivity, as sometimes claimed, it would seem to have only trivial consequences for estimates of the irritative potency of VOCs.

show abstract

An Analysis of Nasal Irritation Thresholds Using a New Solvation Equation

Cited by 71 publications

References 25 publications

Chemesthesis from volatile organic compounds: Psychophysical and neural responses

Chemesthesis from volatile organic compounds: Psychophysical and neural responses

Odor detection of single chemicals and binary mixtures

Trigeminal and olfactory sensitivity: comparison of modalities and methods of measurement

Contact Info

Product

Resources

About