Ageing of Human Bone
Dr Peter Zioupos has developed an improved method for determining a person’s age at the time of death, from small samples of bone and with a level of accuracy previously not obtainable.
Age is one of the four important attributes that a forensic anthropologist may be called on to determine in the case of a body or body parts of unknown origin, together with sex, stature and ethnic background. Current methods of age determination are largely qualitative and are only able to categorise individuals within broad age bands. The accuracy of current age determination methods (e.g. chronology of dental eruption, or fusion of the epiphyses at different skeletal sites) decrease with age and are of limited usefulness beyond the age of skeletal maturity (30-35yrs). Approaches based on histomorphology of bone tissue can be quantitative, but again become increasingly inaccurate after skeletal maturity. The only strictly quantitative analytical technique available analyses the variation of optical isomers of aspartic acid present. However, it is an expensive, complex, slow method and has inherent inaccuracies for female remains.
The new method represents a breakthrough in forensic testing and utilises the fact that with increasing age the bone matrix experiences changes, which are of constitutional, compositional, micromechanical and/or physicochemical nature. These ‘material property’ changes enabled the direct linkage of changes in macromechanical properties of the bone (e.g. elastic stiffness) directly to the age of an individual with good predictive power. Using this novel technique a pilot study consistently demonstrated results within ±3 years of actual age values from small bone samples.
The objective of the researchers is to produce a validated technique, which overcomes current qualitative methods and offers accurate age determination that can be applied in a wide range of criminal and civil investigations. This will enable much more effective investigation of incidents where the identity of the victim or victims is unknown e.g. murder victims or occupants of mass graves.
Dr Peter Zioupos
T: +44 (0)1793 785932
E: p.zioupos@cranfield.ac.uk
