[Microprobe study of bones in the determination of individual age]

Potassium and phosphorus levels and the Ca: P ratio were determined in autopsy material taken from the compact bone substance of the right femur of 25 individuals of various age and either sex. Studies were made under a Tesla BS-300 scanning electron microscope connected to an EDAX-149-10 X-ray detector and a BMG-38100 X-ray analyser using 15 kV accelerating voltage, 100 pA test-current and 20 s measuring time. Different bone substances (lamellae, Haversian canals, interstitial bone) showed similatr Ca: P ratios (p greater than 0.05). However, mean mol-ratio was found to decrease with age and this was still significant (p greater than 0.05) at 95% level. The equation of the regression line was: y = -0.0013x + 1.8275, where y represents Ca: P ratio x the age. There was a close correlation between the molar ratio of Ca and P which enables this method to be applied for the assessment of individual age in forensic medicine and paleoanthropology.