In Vitro Absorption of Atmospheric Carbon Monoxide and Hydrogen Cyanide in Undisturbed Pooled Blood

Biological samples from victims of aircraft accidents are analyzed for carboxyhemoglobin (COHb) and cyanide ion (CN¯) in blood. Such victims quite often suffer large open wounds near the autopsy blood collection sites. Many aircraft crashes result in fires that fill the victim’s atmosphere with smoke rich in carbon monoxide (CO) and hydrogen cyanide (HCN). It is important to determine whether pooled blood in those open wounds may have absorbed CO and HCN after death, which could lead one to erroneously conclude that the presence of COHb and CN¯ in blood was the result of breathing in these combustion gases. A chamber was designed from a laboratory desiccator to establish whether CO and HCN may be absorbed in undisturbed, pooled whole human blood. A magnetic stirring bar was placed at the bottom of the chamber to facilitate air movement. A ceramic plate with concentric rows of holes was above the stirring bar to support a shallow open dish containing 4 mL of heparinized blood. Gas syringes (100-cc) were used to evacuate air from and add pure CO into the chamber. The chamber volume was 9038 cc. The blood was exposed to three concentrations of CO each for two different periods of time. For HCN exposures, an extra dish containing a 5-mL beaker, which contained sodium cyanide (NaCN), was used. Four mL of heparin-treated blood was used in the second dish. One mL of concentrated sulfuric acid was added to the beaker containing NaCN through the lid opening. The volume of the HCN chamber was 8981 cc. Blood COHb and CN¯ concentrations were determined spectrophotometrically. COHb levels of 4.3-11.0% were detected in blood after its exposure to CO at 5532, 8298, 11064, 22129, and 33193 ppm for 30- and 60-min. CN¯ concentrations (1.43-5.01µg/mL) in blood increased with exposure to HCN at 100 and 200 ppm each at 15, 30, 45, and 60 min. Increases in the COHb levels observed in these experiments do not exclude the possibility for higher levels of COHb in blood exposed to highly CO-rich atmospheres from actual fires. It was clearly evident that there is a strong potential for CN¯ levels to increase by the absorption of atmospheric HCN. This selective absorption is consistent with the insolubility of CO and solubility of HCN in water. Thus, postmortem COHb and CN¯ levels should be carefully interpreted.

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• Record URL:
  https://rosap.ntl.bts.gov/view/dot/24985
• Corporate Authors:

  University of Central Oklahoma, Edmond

  100 North University Drive
  Edmond, OK  United States  73034

  Cherokee Nation Distributors

  Garden Ridge, TX  United States  78266

  Federal Aviation Administration

  Civil Aerospace Medical Institute, P.O. Box 25082
  Oklahoma City, OK  United States  73125

  Federal Aviation Administration

  Office of Aerospace Medicine, 800 Independence Avenue, SW
  Washington, DC  United States  20591
• Authors:
  • Thoren, Tiffany M
  • Thompson, Kristi S
  • Cardona, Patrick S
  • Chaturvedi, Arvind K
  • Canfield, Dennis V
• Publication Date: 2012-9

Language

• English

Media Info

• Media Type: Web
• Edition: Final Report
• Features: Figures; References; Tables;
• Pagination: 12p

Subject/Index Terms

• TRT Terms: Absorption; Air transportation crashes; Autopsies; Blood analysis; Blood carbon monoxide levels; Cyanides; Fatalities; Fires; Smoke
• Subject Areas: Aviation; Safety and Human Factors; I80: Accident Studies;

Filing Info

• Accession Number: 01475841
• Record Type: Publication
• Report/Paper Numbers: DOT/FAA/AM-12/13
• Files: NTL, TRIS, ATRI, USDOT
• Created Date: Mar 15 2013 9:48AM