Rafael Casellas and Drs. Nolan F. Mangelson and Lawrence B. Rees, Chemistry and Biochemistry
Human hair is considered to be a minor excretory organ for trace elements. The literature suggests that in some cases trace elemental concentration varies in different races of people. In addition, hair analysis has been used to assess nutritional status in humans. These characteristics attracted archeologists because of the potential of using hair analysis to understand past cultures.1
In this project, I analyzed hair samples from a Greco-Roman cemetery from Egypt. In this cemetery, two groups of people are believed to be buried: Christians and Egyptians. By analyzing the trace elements of hair samples, I hoped to establish differences between these two groups. I also obtained hair samples from living Egyptians to compare with the cemetery hair samples. All the samples were provided by Drs. Wilfred Griggs, and Marvin Kuchar, BYU professors who have excavated in this cemetery since 19812.To perform the analysis, I first washed fifty hair samples with acetone. I then digested the samples in acid and analyzed them with PIXE (proton induced x-ray emission). This analytical technique is very sensitive and can detect elements in the parts per million range.
The analytical results showed no differences between Christian and Egyptian hair samples. On the other hand, ancient hair, with the exception of sample #3, had trace element concentrations approximately ten times higher when compared to modern hair. My first impression was that mummy hair had absorbed trace elements from the soil. If this was true, hair sample #3 had to have been preserved somehow from being contaminated. By looking in Dr. Griggs’ field books about this particular sample, I found that the skull of this mummy had been covered with a resin during the mummification process. This finding confirmed the hypothesis that mummy hair had been contaminated from the soil with time. An electron micrograph of a modern hair and mummy hair sample # 3 corroborated further the hypothesis. In conclusion, trace elemental hair analysis of archeological samples should be severely questioned unless the hair has been well preserved.
References
- Schroeder A. Henry et al., Trace Elements in Human Hair, The Journal of investigative Dermatology, pp 71-78, 1969.
- C. Wilfred Griggs et al., Evidences of a Christian Population in the Egyptian Fayum and Genetic and Textile Studies of the Akhmim 2
Noble Mummies, BYU Studies 33, no. 2, 1993.