“Cyanide has a short half-life and may be lost over the postmortem period unless tissues are adequately preserved,” Dr. Cina said. “In this case, due to advanced putrefaction of the tissues, no cyanide was detectable in the tissues or small amounts of gastric contents recovered following exhumation of the body.”
A lethal level of cyanide was detected in the initial blood sample taken by the Medical Examiner’s office on July 21, 2012. That finding was confirmed last month by an independent toxicology lab.
“This sample was preserved with sodium fluoride in accordance with office practice,” Dr. Cina said. “The sample was retested in our toxicology laboratory and at NMS Labs, and the positive results were confirmed.”
The post-exhumation autopsy also revealed severe stenosis (75 percent) of one of Mr. Khan’s major coronary arteries, Dr. Cina said.
“Since cyanide affects oxygen utilization in the tissues, it follows logically that a natural disease process that already limits blood flow to the heart could render an individual particularly susceptible to death due to this toxin,” he said. “For this reason, coronary artery disease is deemed a contributory factor to this fatality.”
The Medical Examiner has determined that Mr. Khan, 46, died of cyanide toxicity and ruled the manner of death a homicide. The autopsy results have been turned over to the Chicago Police Department.