Inhalation Toxicology. VIII: Establishing Heat Tolerance Limits for Rats and Mice Subjected to Acute Exposures at Elevated Air Temperatures

• Main Authors: Crane,Charles R, Sanders,Donald C
• Format: Report
• Language: English
• Subjects: AIRCRAFT FIRES; ATMOSPHERIC TEMPERATURE; AVIATION SAFETY; COLLAPSE; COMBUSTION PRODUCTS; COOLING; EXPOSURE(PHYSIOLOGY); HEAT STRESS(PHYSIOLOGY); HYPERTHERMIA; LPN-FAA-AM-A-78-TOX-36; LPN-FAA-AM-B-79-TOX-39; MICE; RATS; SMOKE; Stress Physiology; TIME; TOXICITY; Toxicology

Experimental animal subjects are used most commonly to assess the toxicity of thermal decomposition products (smoke) from burning materials. Nascent smoke is obviously quite hot; therefore, the design of smoke toxicity assay systems must provide for adequate cooling of the gases prior to exposure of the animals. This research has addressed the question of how much cooling is required. Rats and mice were exposed to elevated air temperatures over the range of 38C to 110C. The exposure duration required to produce hyperthermic collapse (physical incapacitation) was measured for each temperature. A graph of time-to-collapse as function of exposure temperature was constructed for each species and statistically derived equations were fit to each data set. Times-to-collapse ranged, for the rat, from 60 minutes at 40C to less than 4 minutes at 110C. For the mouse, they ranged from approximately 60 minutes at 40C to 2.5 minutes at 90C. The significance of these findings as they relate to smoke toxicity testing is discussed.