The impact of moderate heating on human bones: an infrared and neutron spectroscopy study

This study aims to analyse human bones exposed to low/medium temperatures (200-650 degrees C) under experimentally controlled conditions, both oxidizing and reducing, using complementary optical and neutron vibrational spectroscopy techniques. Clear differences were observed between the aerobically and anaerobically heated bones. The organic constituents disappeared at lower temperatures for the former (ca 300 degrees C), while they lingered for higher temperatures in anaerobic environments (ca 450-550 degrees C). Unsaturated non-graphitizing carbon species (chars) were detected mainly for anaerobically heated samples, and cyanamide formation occurred only at 650 degrees C in reducing settings. Overall, the main changes were observed from 300 to 400 degrees C in anaerobic conditions and from 450 to 500 degrees C in aerobic environments. The present results enabled the identification of specific spectroscopic biomarkers of the effect of moderate temperatures (less than or equal to 650 degrees C) on human bone, thus contributing to a better characterization of forensic and archaeological skeletal remains subject to heating under distinct environmental settings. In particular, these data may provide information regarding cannibalism or ancient bone boiling and defleshing rituals.

Automated summary

This study analyzed human bones exposed to low/medium temperatures using optical and neutron vibrational spectroscopy techniques. Clear differences were observed between bones heated in aerobic and anaerobic conditions, with specific spectroscopic biomarkers identified at different temperature ranges.