Iceman's Mummification—Implications from Infrared Spectroscopical and Histological Studies

Abstract

A skin sample from the Iceman (Otzi, Similaun Man, Man from Hauslabjoch) was studied by means of IR spectroscopy and histology, and the results were compared to those obtained from nine other more recent human tissue samples with known case reports. Attenuated total reflection IR spectroscopy was used for studying the fate of proteins and lipids in these rare skin tissues. This technique provided a simple yet powerful means for semiquantitative determination of the main compound classes found in skin samples, namely, triacylglycerols, their main breakdown products (fatty acids), and proteins. When combined with histology, I R spectroscopy provided reliable information about the main conditions uader which mummification of the samples had taken place. In the case of the 5300-year-old Iceman, preserved collagen contributed to the conservation of morphological structures of the skin, although no Keywords adipocere * IR spectroscopy -lipidsmummification * skin cellular structures such as nuclei survived. In addition, post-mortal alterations such as hydrolysis of triacylglycerols and phospholipids into fatty acids were unequivocally demonstrated. The solidified fatty acids provided a certain degree of preservation to the tissue characteristic of adipocere. Based on this observation, taken together with the concomitant loss of epidermis, we suggest that Iceman's body was submerged in water for a period of at least several months prior to desiccation. Results from other research disciplines support our conclusions.

Exploration of anthropological specimens by GC‐MS and chemometrics

“…The authors suggest low bacterial activity after the Iceman's death, because they detected only small amounts of fatty acids with uneven carbon numbers, branched fatty acids (both characteristic for bacterial activity), and no trans-fatty acids. Infrared spectroscopic and histological studies supported these conclusions (Bereuter, Mikenda, & Reiter, 1997).…”

“…With high probability the wound caused by the arrow, together with the remote area and the climate at an altitude of 3,200 m in the Alps caused the death. According to one theory (Seidler et al, 1992), the corpse was first desiccated by mountain winds and later enclosed by snow and ice; another theory (Bereuter, Mikenda, & Reiter, 1997) suggests that Iceman's body was first submerged in water for at least several months prior to desiccation. Both theories are supported by observations.…”

Molecular paleontology

“…None of these hypotheses, however, can entirely account for a number of features which are being progressively revealed by the investigations carried out independently in several laboratories since the first exploration of the iceman's site. For example, histological and biochemical analyses have shown an almost complete loss of the iceman's epidermis, acompanied by profound postmortem alterations of skin triacylglycerols, which implies a prolonged (up to several months) immersion in water before dry weather and, possibly, cold winds desiccated the corpse [64]. The Tyrolean iceman has been the object of a detailed molecular analysis by research teams in Munich and Oxford.…”

Evidence of adipocere in a burial pit from the foot and mouth epidemic of 1967 using gas chromatography–mass spectrometry

“…Adipocere is a decomposition product formed by bacterial mediated decay of triacylglycerols in animal and human body fats [1][2][3]. In many countries, the removal of soft tissues from human bodies is unethical and prohibited by law.…”