Post-mortem Interval of Buried Carcasses in a Tropical Rainforest Vegetation of Nigeria

Abstract

Background: Most of the murder victims in Nigeria are concealed in shallow graves or clandestine paths or bushes. Knowledge of post-mortem interval (PMI) of buried carcasses is useful in estimating time since death for buried homicide scenarios. The PMI of buried remains is different from that of remains on the soil surface. Aims and Objectives: The study aimed at investigating the PMI of buried remains in a tropical rainforest vegetation of Nigeria using matured domestic pigs as human analogs. Materials and Methods: Four animals were used for this study. Animals were sacrificed and buried in one-foot-depth graves. A flat wood was placed on top of the animals before it was covered with sand so that the visible changes can be monitored during the study period. The study was carried out during the rainy and dry seasons. Soil analysis was carried out to ensure that there was no chemical substance inhibiting decomposition. Results: Animals did not completely skeletonize within the study period (168 days). However, four stages of decomposition were identified within the study period – Fresh, bloat, active decay, and advanced decay stages. Conclusions: The PMI was influenced by fungi activities and rain infusion. On the last day of the study, the decomposition was at the advanced decay stage and only few bones of the head, neck, trunk, and limbs were visible with greyish discoloration of the skin and other visceral structures. The visible post-mortem changes of the buried carrions noted in this study may be used to estimate the time of death of buried humans in a tropical rainforest vegetation of Nigeria.