Experimental mummification-In the tracks of the ancient Egyptians

Understanding natural and artificial postmortem alterations in different tissues of the human body is essential for bioarchaeology, paleogenetics, physical anthropology, forensic medicine, and many related disciplines. With this study, we tried to gain a better understanding of tissue alterations associated with the artificial mummification techniques of ancient Egypt, in particular for mummified visceral organs. We used several entire porcine organs and organ sections (liver, lung, stomach, ileum, and colon), which provided a close approximation to human organs. First, we dehydrated the specimens in artificial natron, before applying natural ointments, according to the ancient literary sources and recent publications. We periodically monitored the temperature, pH value, and weight of the specimens, in addition to radiodensity and volumetric measurements by clinical computed tomography and sampling for histological, bacteriological, and molecular analyses. After seven weeks, mummification was seen completed in all specimens. We observed a considerable loss of weight and volume, as well as similar courses in the decay of tissue architecture but varying levels of DNA degradation. Bacteriologically we did not detect any of the initially identified taxa in the samples by the end of the mummification process, nor any fungi. This feasibility study established an experimental protocol for future experiments modeling ancient Egyptian mummification of visceral organs using human specimens. Understanding desiccation and mummification processes in non-pathological tissues of specific visceral organs may help to identify and interpret disease-specific alterations in mummified tissues in ancient Egyptian canopic jars and organ packages contained in whole mummies.