title: The Influence of Humidity on Assessing Irritation Threshold of Ammonia.
abstract: A large number of occupational exposure limit values (OELs) are based on avoiding of sensory irritation of the eyes and the upper respiratory tract. In order to investigate the chemosensory effect range of a chemical, odor and sensory irritation thresholds (lateralization thresholds, LTs) can be assessed. Humidity affects olfactory function and thus influences odor thresholds; however, a similar effect has not been shown for sensory irritation thresholds. The purpose of the present study was to explore whether LTs for ammonia vapor vary depending on the water vapor content of the inspired stimulus. Eight healthy nonsmoking volunteers were simultaneously exposed to ammonia vapor through one nostril and clean air through the other and were asked to determine which nostril received the chemical. Within experimental runs, ascending ammonia concentrations (60-350 ppm) that were either dry or humidified were administered at fixed time intervals. Geometric mean LTs obtained at wet (181 ppm) or dry (172 ppm) conditions did not differ significantly (P = 0.19) and were within the range of those reported by previous studies. These results suggest that humidity is not a critical factor in determining sensory irritation thresholds for ammonia, and future studies will examine if these findings are transferable to sensory irritation thresholds for other chemicals.
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
authors.forename: Christian
authors.identifier: 0000-0001-7591-0568
authors.initials: C
authors.lastname: Monsé
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Sucker
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
authors.forename: Frank
authors.identifier: 0000-0002-0870-4171
authors.initials: F
authors.lastname: Hoffmeyer
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
authors.forename: Birger
authors.initials: B
authors.lastname: Jettkant
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
authors.forename: Hans
authors.initials: H
authors.lastname: Berresheim
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
authors.forename: Jürgen
authors.identifier: 0000-0001-6831-7854
authors.initials: J
authors.lastname: Bünger
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr-University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, 44789 Bochum, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Brüning
mesh_terms: D000280:Administration, Inhalation; D000328:Adult; D000641:Ammonia / Q000008:administration & dosage / Q000737:chemistry / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D006813:Humidity; D008297:Male; D008875:Middle Aged; D012684:Sensory Thresholds / Q000187:drug effects* / Q000502:physiology*; D012903:Smell / Q000187:drug effects* / Q000502:physiology*; D020711:Threshold Limit Values
chemical_list: D000641:Ammonia