Applications for Drowning Identification by Planktonic Diatom Test on Rats in Forensic Medicine

We established a model of drowning, and by investigating diatoms in lung, liver, kidney, and long bone marrow of rats at different time to discuss the cause of death. The organs of 35 rats were extracted 0.5 h, 1 h, 6 h, 12 h, 24 h and 48 h after drowning and the organs of sham-drowning group killed by mechanical asphyxia were extracted 1 h after body immersed in water. The organs were digested by acid, and the diatoms were analyzed by statistics. Results shown the detection rate was 100% in lung, and the positive rate of all the extracted organs was 100% 6 hours after drowning except the sham-drowning group. No diatoms were detected in the liver, kidney and bone marrow of the sham-drowning group, just only one case was positive in the lung. So it is concluded that the detection rate of diatoms could be considered as important evidence in drowning determination.