| Title | Variations in Time-to-Incapacitation and Blood Cyanide Values for Rats Exposed to Two Hydrogen Cyanide Gas Concentration |
|---|---|
| Record ID | 39581 |
| Personal Name Creator |
Chaturvedi, Arvind K.; Endecott, Boyd R.; Ritter, Roxane M.; Sanders, Donald C. |
| Corporate Creator | Civil Aeromedical Institute |
| Corporate Contributor |
United States. Office of Aviation Medicine |
| Publisher | Civil Aerospace Medical Institute |
| Publication Date | 19930500 |
| Language | English |
| Abstract | It has been suggested that protective breathing devices protect aircraft passengers from combustion products for 5 min. during evacuation and for 35 min. during in-flight-plus-evacuation. Hydrogen cyanide (HCN), a combustion gas, produces incapacitation at relatively low concentrations, and time-to-incapacitation (ti) is an applicable index for predicting escape from a fire. Variations in ti and blood cyanide (CN-) at specific HCN gas exposure concentrations have not been evaluated. Therefore, ti and blood CN- at ti for two HCN concentrations that produce 5- and 35 min ti were determined in male Sprague-Dawley rats. Blood CN- levels as a function of HCN exposure time were measured. Animals were individually exposed to HCN gas in a chamber equipped with a rotating cage, and ti was recorded as the time from insertion of the animal into the cage until it could no longer walk. At incapacitation and at selected intervals prior to ti, rats were quickly removed from the cage and killed for blood collection and CN- quantitation. Chamber HCN concentrations were monitored during the exposures. For the 5-min. test (mean ± SD; n = 50), HCN gas = 184 ± 10.0 ppm, ti = 5.1 ± 0.8 min., and blood CN- = 2.3 ± 0.5 mg/mL; for the 35-min. test, HCN gas - 64 ± 6.1 ppm, ti = 31.1 ± 11.2 min., and blood CN=4.2 ± 1.3 mg/mL. Blood CN- levels increased as a function of HCN exposure time, but the blood CN- level at the 5-min. ti was half of the 35-min. blood CN- level; the HCN gas uptake rate at 184 ppm was about 3 times that at 64 ppm. These findings suggest that the blood CN- level at incapacitation may vary substantially, depending upon the HCN exposure concentration; an equation is proposed for predicting blood CN-levels in rats. |
| Rosap ID | dot:21359 |
| Rosap URL | https://rosap.ntl.bts.gov/view/dot/21359 |
| TRT Terms | Air transportation crashes; Fire; Smoke; Poisonous gases; Blood analysis; Toxicity; Experiments; Laboratory animals; Rats; Toxicology |
| General Subjects | Aircraft accidents; Fire; Combustion gases; Gases, Asphyxiating and poisonous; Hydrocyanic acid--Toxicity testing; Blood--Analysis; Rats as laboratory animals |
| Classification | NTL - AVIATION - Aviation Safety/Airworthiness; NTL - SAFETY AND SECURITY - Accidents; NTL - SAFETY AND SECURITY - Aviation Safety/Airworthiness |
| Geographical Coverage |
United States |
| Report Number | DOT/FAA/AM-93/8 |
| Resource type | Tech Report |
| URL | https://ntlrepository.blob.core.windows.net/lib/39000/39500/39581/AM93-08.pdf |
| Format | |
| Database | NTL Digital Repository |