Mechanisms of the Combined Effects of Inhaled Chemical Contaminant Exposure and Hypoxia on Real Time Performance in Rats
Abstract
Physiological episodes (PEs) have been attributed to, among other things, hypoxia and exposures to chemical contaminants. The consensus to date is that most, if not all, of the contaminants to which aircrew are exposed are not present at sufficient levels to induce PE-like symptoms. There is also scant evidence that classic hypoxia alone is the cause. The potential additivity or synergy of the effects of simultaneous exposure to chemical contaminants and hypoxia has not been closely examined, particularly with respect to subtle central nervous system (CNS) or motor coordination effects that are relevant to aviator performance.The objective of this research was to understand the mechanisms of combined inhalation of chemical contaminants and hypoxia in an in vivo rat model to better assess risk of the combined exposures as a potential cause of PEs. Following a previously performed dedicated analysis and review of chemical compounds detected in and around Navy aircraft, trimethylsilanol (TMS) and carbon monoxide (CO) were identified as top candidates for combination studies to test for any additivity or synergy of exposure-related effects between themselves and hypoxia that could potentially contribute to the occurrence of PEs. TMS exposure has been shown to have depressant effects on the CNS, while CO is known to preferentially bind to hemoglobin and prevent oxygen delivery to tissues within the body. Both were seen as potential candidates to have additive or synergistic effects with hypoxia exposures that are also known to impact CNS function.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2023
- Accession Number
- AD1211997
Entities
People
- Andrew J. Keebaugh
- Brian C. Sharits
- Hana I. Warwick
- Joyce G. Rohan
- Maria A. Spencer
- Nathan M. Gargas
- R. A. James
Organizations
- Naval Medical Research Unit Dayton