NCJ Number
192041
Journal
Journal of Forensic Sciences Volume: 46 Issue: 6 Dated: November 2001 Pages: 1421-1425
Date Published
November 2001
Length
5 pages
Annotation
This study examined the toxicologic significance of blood cyanide concentrations in fire victims.
Abstract
Headspace gas chromatography was used for cyanide detection. Analysis of blood samples from 10 fire victims (postmortem interval = 8 hours to 3 to 5 days) detected zero to 11.9 mg/L of cyanide and a large difference in cyanide concentrations among victims. Carboxyhemoglobin (COHb) saturation was in the range of 24.9 to 84.2 percent. To examine the effects of methemoglobinemia and postmortem interval on blood cyanide concentrations in fire victims, an experiment was carried out by using rabbits as the animal model. The rabbits were sacrificed by intramuscular injection of 1 mL/kg 2 percent potassium cyanide 5 minutes after intravenous injection of 0.33 mL/kg of 3 percent sodium nitrite (Group A, n=3) or physiological saline (Group B, n=6). Average methemoglobin contents immediately before potassium cyanide administration were 6.9 percent and 0.8 percent in Groups A and B, respectively. Average cyanide concentrations in cardiac blood at the time of death were 47.4 and 3.56 mg/L respectively. When blood-containing hearts of the rabbits (n=3 for Group B) were left at 46 degrees C for the first 1 hour, at 20-25 degrees C for the next 23 hours, and then at 4 degrees C for 48 hours, approximately 85 percent and 46 percent of the original amounts of blood cyanide disappeared within 24 hours in Groups A and B, respectively. After the 72-hour storage period, 37 percent and 10 percent, respectively, of the original amounts of cyanide remained in the blood. When the other three hearts in Group B were left at 20-25 degrees C for the last 48 hours without refrigeration, cyanide had disappeared almost completely by the end of the experiment. The current results and those published in the literature demonstrate that the toxic effects of cyanide on fire victims should not be evaluated based solely on the concentration in blood. 1 table, 5 figures, and 16 references