INVESTIGATION ON THE DEVELOPMENT OF THE USE OF NATRON SALT IN THE ANCIENT EGYPTIAN EMBALMING PRACTICES

Artificial mummification of the bodies in ancient Egypt was practiced making use of Natron as dehydrating agent. It is in the New Kingdom, specifically the 18 th Dynasty (c.1500-1300 BC), when a solution of Natron was used to preserve the elite, rather than dry natron salt as previously supposed. To test this hypothesis we have treated pig skin with Natron prepared following Sandison [1]. The skin was treated with salt in dry conditions (covered with salt) and in the liquid formulation (immersed in a salt saturated solution, 4M, pH 10.93). Both samples were maintained in an oven at about 40°C for total 70 days to mimic the Egyptian environmental conditions. Fourier Transform InfraRed (FTIR) spectra of pig skin treated with Natron were studied in the OH stretching band range (3800-3000 cm-1) and in the Amide I and II region (1700-1500 cm-1), the peptide backbone absorption region. Both the features change in dependence on the treatment with salt. In pig skin maintained in salt solution, the changes in the ν(OH) shape and the dramatic increase in the Amide II band amplitude with respect to Amide I suggested the amino-group involvement in the collagen conformational modifications produced by salt. In pig skin treated with dry Natron a continuous and regular decrease of the ν(OH) intensity was observed as a consequence of the water removal by the salt but Amide II band did not change significantly. Parallel SEM measurements, accomplished by recording the cathodoluminescence emitted by the samples submitted to both the treatments, monitored the time kinetic of salt penetration in the tissues. The main results obtained were compared with those collected from measurements on the skin of a human volunteer successfully embalmed in recent times [2] and on the skin fragments of Egyptian mummies belonging to the IV-XI Dynasties [3]. [1] A. T. Sandison (1963) Journal of Near Eastern Studies 22:259-267 [2] http://www.mirror.co.uk/news/weird-news/mummifying-alan-taxi-driver-alan-86266 [3] C. Stani, A. Baraldi, R. Boano, R. Cinquetti, and M. G. Bridelli (2014). J. Biol. Res. 87: 2133, 26-28. Investigation on the development of the use of Natron salt in the ancient Egyptian embalming practices. Available from: https://www.researchgate.net/publication/303666300_Investigation_on_the_development_of_the_use_of_Natron_salt_in_the_ancient_Egyptian_embalming_practices [accessed Jun 28, 2017].