Stability of cyanide in cadavers and in postmortem stored tissue specimens: a review

The toxicological and postmortem analysis of fire victims' blood and tissue can disclose the type and quantity of toxic species, such as carbon monoxide or hydrogen cyanide, that they inhaled prior to death. For fire cases, these toxicological data can reveal objective data about the nature and circumstances of a fire, and thus assist both the Medical Examiner and the Fire Investigator in their investigations. Assigning a level of significance to cyanide concentrations found in the blood and tissue of fire victims is often hampered by the fact that cyanide is inherently unstable in cadavers and in stored tissue samples. Numerous researchers have provided insight into and characterized the stability of cyanide in the body and in collected biological specimens. Based on studies by these researchers, the rate of transformation of cyanide in blood and tissue specimens is dependent on the initial cyanide concentration in the sample at time of death, the length of time that a sample remains in the cadaver, the length of time that a sample remains in storage, and the preservation (e.g., addition of sodium fluoride to sample) and storage conditions (e.g., temperature) of the sample.