Human bone probed by neutron diffraction: the burning process

Area of Science:

• Bone Diagenesis
• Materials Science
• Crystallography

Background:

• Understanding heat-induced changes in bone is crucial for forensic and archaeological investigations.
• Previous studies have not comprehensively analyzed burned human bone using neutron diffraction.

Purpose of the Study:

• To elucidate the heat-induced diagenesis process in human bone.
• To investigate chemical and crystallographic changes in bone upon heating.
• To establish the relationship between temperature and bone matrix transformation.

Main Methods:

• Neutron diffraction analysis of human bone samples (femur, humerus, tibia).
• Heating samples to maximum temperatures ranging from 400°C to 1000°C under aerobic conditions.
• Complementary analysis using Fourier transform infrared spectroscopy.

Main Results:

• Significant crystallographic and domain size variations were observed, primarily between 700°C and 900°C.
• Bone heated above 700°C showed an organized, highly symmetric inorganic matrix, lacking carbonates and organic matter.
• Bone heated below 700°C exhibited lower crystallinity with residual carbonates, lipids, and collagen.

Conclusions:

• The study provides the first neutron diffraction data on burned human bone.
• Distinct thermal thresholds (700°C) dictate significant changes in bone's inorganic and organic composition.
• Findings are relevant for archaeology, biomaterials science, and forensic science applications.