A Comparison of Human Decomposition in an Indoor and an Outdoor Environment

In the medicolegal context, forensic anthropologists assist investigators by gathering information from skeletal remains. While humans decompose in both indoor and outdoor environments, little research has been performed on the differences in the decomposition rate and process between subjects in an indoor environment and subjects in an outdoor environment. Limited accessibility to appropriate facilities for a comparison study between indoor and outdoor decomposition rates has prevented such research from being attempted. Documented through daily notes and photographs, six human subjects were observed from the fresh to the end of the bloat stages of decomposition. Three subjects were placed in an indoor structure. The other three decomposed in an outdoor environment. All subjects were compared to determine if decomposition rates differed between the indoor and outdoor subjects.

From September 2004 through July 2005, six unembalmed, unautopsied human bodies were observed at the Anthropology Research Facility in Knoxville, Tennessee. The indoor structure was heated in winter and air conditioned during the fall. The air conditioner was broken throughout the spring/summer months. Decomposition rates were compared across seven variables and three stages using accumulated degree days (ADD). ADD was calculated for each subject using weather data gathered from an indoor/outdoor thermometer installed in the indoor structure. In the spring, summer, and fall months, indoor subjects decomposed faster than outdoor subjects. During the winter months, the indoor subject decomposed faster. Further research is necessary to determine the exact source of the differences in decomposition rates.