[Experimental studies of postmortem diffusion of toluene in blood, brain, muscle and fat of rats exposed to toluene vapor].

This report describes the postmortem diffusion of toluene in blood, brain, muscle and fat of rats exposed to toluene vapor. After exposure to toluene vapor (4,000 ppm) for 15 and 60 min, rats were killed by CO2 exposure and left for 12 and 24 hours in a fresh air. Toluene concentrations in blood, brain, muscle and fat were determined by head space gas chromatography. Postmortem decrease of toluene concentration in blood and increase of that in fat were observed with postmortem interval in both exposure conditions. But an extremely larger postmortem changes in the short exposure than those in the long exposure were observed. These are due to the facts that the value of fat/blood toluene concentration ratio at the time of death in the short exposure (3.3) was extremely smaller than that in the long exposure (10.5). Postmortem increase in muscle was also observed slightly. Postmortem concentrations in brain in both exposure intervals were relatively constant during these experiments. This postmortem stability is attributable to its anatomical features. These results suggest that brain toluene concentration at the autopsy is useful for the estimation of blood toluene concentration at the time of death and by comparison between toluene concentration in blood and that in brain it may be possible to presume the circumstances of death.