A pre-Hispanic head.
This report on a male head revealed biologic rhythms, as gleaned from hydrogen isotope ratios in hair, consistent with a South-American origin and Atomic Mass Spectrometry radiocarbon dating (AMS) compatible with the last pre-Hispanic period (1418-1491 AD, 95.4% probability). Biopsies showed exceptionally well-preserved tissues. The hair contained high levels of toxic elements (lead, arsenic and mercury) incompatible with life. There was no evidence for lead deposition in bone consistent with post-mortem accumulation of this toxic element in the hair. We propose that the high content of metals in hair was the result of metabolic activity of bacteria leading to metal complexation in extra cellular polymeric substances (EPS). This is a recognized protective mechanism for bacteria that thrive in toxic environments. This mechanism may account for the tissues preservation and gives a hint at soil composition where the head was presumably buried. Our results have implications for forensic toxicology which has, hitherto, relied on hair analyses as one means to reconstruct pre-mortem metabolism and for detecting toxic elements accumulated during life. Our finding also has implications for other archaeological specimens where similar circumstances may distort the results of toxicological studies.
Bianucci
Raffaella
R
Laboratory of Anthropology, Department of Animal and Human Biology, University of Turin, Turin, Italy. raffaella.bianucci@unito.it
Jeziorska
Maria
M
Lallo
Rudy
R
Mattutino
Grazia
G
Massimelli
Massimo
M
Phillips
Genevieve
G
Appenzeller
Otto
O
D000328:Adult; D001808:Blood Vessels / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D005580:Fossils; D006197:Hair / Q000737:chemistry* / Q000378:metabolism* / Q000382:microbiology / Q000648:ultrastructure; D006257:Head; D006630:Hispanic or Latino; D049668:History, 15th Century; D006801:Humans; D006859:Hydrogen; D007150:Immunohistochemistry; D008297:Male; D013058:Mass Spectrometry; D009132:Muscles / Q000378:metabolism; D011041:Poisoning / Q000175:diagnosis; D012867:Skin / Q000166:cytology / Q000648:ultrastructure; D012886:Skull / Q000648:ultrastructure; D013020:South America
D006859:Hydrogen