Sensory Irritation Potential of Aviation-Related Chemical Contaminants in Normoxic and Hyperoxic Conditions
Abstract
Physiological Episodes (PEs) involving military aviators include a variety of both objective and subjective symptoms. Included among these are respiratory symptoms that resemble sensory irritancy. Sensory irritation in the respiratory system involves the response of nervous system reflexes that are perceived as a burning, stinging or itching in the upper airways. Chemical exposure has been suspected as a cause of these upper airway symptoms because of the presence of chemicals, fuels, fluids, and jet exhausts found in the aviation environment and within proximity to military aircraft (Mumy, 2019). A number of chemicals were identified from air sampling in and around tactical aircraft that may be capable of producing sensory irritancy for which either no experimental data exist, or data exists that does not fall within standard testing guidelines to determine the degree of sensory irritancy. Sensory irritation involves the response of nervous system reflexes to inhaled chemicals that typically act to lower the respiratory rate in mice. The concentration of an airborne contaminant that produces a 50% decrease in respiratory rate from the baseline respiratory rate is expressed as the Respiratory Depression 50% (RD50) value. This report contains results for calculating the RD50 value for five chemicals presumed to be sensory irritants that were detected in air sampling in and around tactical aircraft. These five chemicals are isopropanol, 1,2,4-trimethylbenzene, cyclobutylamine, naphthalene and nitrogen dioxide. Four of the five chemicals produced respiratory depression consistent with sensory irritancy. Nitrogen dioxide exposure did not cause a respiratory depression. The RD50 values determined herein for these four chemicals in normoxic 21% oxygen are isopropanol at 77,545 mg/m3 (31,547 ppm), 1,2,4-trimethylbenzene at 1,408 mg/m3 (286 ppm), cyclobutylamine at 1,208 mg/m3 (415 ppm) and naphthalene at 25.9 mg/m3 (4.9 ppm).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 08, 2022
- Accession Number
- AD1171391
Entities
People
- Andrew J. Keebaugh
- Angel D Hulgan
- David M. Holtzapple
- Erin L. Roberts
- Hana I. Warwick
- Joshua L Stricker
- Karen L. Mumy
- R. A. James
- Samuel M Fullen
- Shannon H. Romer
Organizations
- Naval Medical Research Unit Dayton
- Oak Ridge Institute for Science and Education