The Significance of Detecting Diatoms in Spleen Tissue for the Postmortem Diagnosis of Drowning

Abstract

The aim of this study was to elucidate the diatomological investigation and the forensic role of spleen tissue in cases of drowning or non-drowning. Specimens of spleen tissue and other organ tissue from 136 drowning cases, as well as 21 cases where death resulted from causes other than drowning (acting as controls), were examined for the presence of diatoms. The diatom test was performed on all cases using the acid digestion method, involving fumed nitric acid on a hot sand bath. The presence of diatoms in spleen tissue was observed in drowning cases but not in non-drowning cases. Diatoms in spleen tissue showed a positive association with drowning (P=0.011). Among the 136 drowning cases, diatoms were most frequently found in lung tissue (n=134, 99%), followed by spleen (n=33, 24%), kidney (n=28, 21%), liver (n=27, 20%), and heart (n=22, 16%) tissues. Moreover, in 95 cases where putrefaction did not progress, diatoms were detected in spleen tissues in 14 cases, indicating that the highest detection rate among other enclosed organ tissues, excluding lung tissues. Furthermore, a significant correlation was observed between the presence of diatoms in spleen tissue and those in enclosed organs, including the liver, kidney, and heart, but not in lung tissues. Our results revealed a significant correlation between the presence of diatoms in spleen tissue and drowning. Thus, the present study provides evidence that the presence of diatoms in spleen tissue may be a reliable indicator of death by drowning.