Maxwell, LaraCliburn, Kacey D.2021-08-032021-08-032021-05https://hdl.handle.net/20.500.14446/330177Millions of people in the world use Cannabis sativa for its mood-altering properties. The main psychoactive component of cannabis, delta^9-tetrahydrocannabinol (THC) is commonly detected in forensic toxicology laboratories handling motor vehicle and plane crash fatalities. As few studies characterized cannabinoid distribution and postmortem redistribution, we developed a study to investigate postmortem cannabinoid concentrations in rabbits following controlled cannabis administration via a smoking machine. Five rabbits were exposed to cannabis smoke and a broad array of biological specimens were collected immediately upon death. High THC concentrations were observed in lungs, moderate concentrations were seen in the brain, heart, and kidneys, and low concentrations were noted in the liver. A physiologically based pharmacokinetic (PBPK) model was constructed to describe blood and tissue THC concentrations in rabbits following the administration of smoked cannabis by inhalation. The results showed similar THC concentrations in blood and tissues between the predicted and experimental data. Building upon the disposition of cannabinoids in various postmortem fluids and tissues in the rabbits, we evaluated time- and temperature-dependent changes in the concentrations of cannabinoids after rabbit carcasses were stored under room temperature or refrigerated conditions for various times after death. No significant differences in THC concentrations were observed between rabbits stored at room temperature versus under refrigerated conditions. When THC concentrations from various postmortem intervals (PMI) were compared to those observed at PMI 0 h, significant THC concentration changes in heart blood and peripheral blood were noted only in refrigerated samples collected at 2 and 16 h after death. Mean central:peripheral and liver:peripheral ratios for THC were 1.6 and 2.9, respectively. These data indicate that THC was not prone to substantial postmortem redistribution in the rabbit. This was the first study to consider either cannabinoid distribution or postmortem redistribution after inhaled cannabis administration using an animal model. The findings add substantially to our understanding of postmortem cannabinoid concentrations and can aid forensic toxicologists in the interpretation of cannabinoid findings in death investigations.application/pdfCopyright is held by the author who has granted the Oklahoma State University Library the non-exclusive right to share this material in its institutional repository. Contact Digital Library Services at lib-dls@okstate.edu or 405-744-9161 for the permission policy on the use, reproduction or distribution of this material.Dissertation