An assessment of air quality reflecting the chemosensory irritation impact of mixtures of volatile organic compounds

• Published in: Environment international 2016-01, Vol.86, p.84-91
• Main Authors: Abraham, Michael H., Gola, Joelle M.R., Cometto-Muñiz, J. Enrique
• Format: Article
• Language: English
• Subjects: Air - analysis; Air - standards; Air Pollutants - analysis; Air Pollutants - toxicity; Air quality index; Chemosensory irritation; Eye - drug effects; Humans; Irritants - analysis; Irritants - toxicity; Models, Theoretical; Nose - drug effects; Quantitative structure-activity relationships (QSAR); Sensory Thresholds - drug effects; Signal Detection, Psychological; Threshold Limit Values; VOC mixtures; VOCs dose addition; VOCs response addition; Volatile organic compounds (VOCs); Volatile Organic Compounds - analysis; Volatile Organic Compounds - toxicity
• ISSN: 0160-4120; 1873-6750
• DOI: 10.1016/j.envint.2015.07.012

We present a method to assess the air quality of an environment based on the chemosensory irritation impact of mixtures of volatile organic compounds (VOCs) present in such environment. We begin by approximating the sigmoid function that characterizes psychometric plots of probability of irritation detection (Q) versus VOC vapor concentration to a linear function. First, we apply an established equation that correlates and predicts human sensory irritation thresholds (SIT) (i.e., nasal and eye irritation) based on the transfer of the VOC from the gas phase to biophases, e.g., nasal mucus and tear film. Second, we expand the equation to include other biological data (e.g., odor detection thresholds) and to include further VOCs that act mainly by “specific” effects rather than by transfer (i.e., “physical”) effects as defined in the article. Then we show that, for 72 VOCs in common, Q values based on our calculated SITs are consistent with the Threshold Limit Values (TLVs) listed for those same VOCs on the basis of sensory irritation by the American Conference of Governmental Industrial Hygienists (ACGIH). Third, we set two equations to calculate the probability (Qmix) that a given air sample containing a number of VOCs could elicit chemosensory irritation: one equation based on response addition (Qmix scale: 0.00 to 1.00) and the other based on dose addition (1000*Qmix scale: 0 to 2000). We further validate the applicability of our air quality assessment method by showing that both Qmix scales provide values consistent with the expected sensory irritation burden from VOC mixtures present in a wide variety of indoor and outdoor environments as reported on field studies in the literature. These scales take into account both the concentration of VOCs at a particular site and the propensity of the VOCs to evoke sensory irritation. [Display omitted] •We introduce an air quality index based on sensory irritation from VOCs mixtures.•The method considers each VOC concentration and its sensory irritation impact.•Two scales are set: one based on response addition and the other on dose addition.•The outcome is consistent with VOC recommended TLVs based on sensory irritation.