Sex- and age-related variation in elemental concentrations of contemporary Japanese ribs.

Twenty elements (Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V, Zn, C and N) in 42 Japanese ribs (forensic medical autopsy cases) were determined using inductively coupled plasma atomic emission spectrometry (ICP-AES), atomic absorption spectrometry (AAS) and carbon and nitrogen analysis to examine sex- and age-related variation in the concentrations of these elements. Bone Fe and Pb concentrations were significantly higher, while P concentrations were lower in males. Elements which showed age-related variation were Ca, P, Al, Fe, Mg, Na, Pb and Zn. Of these, Al, Fe, Pb and Zn linearly accumulate in bone with advancing age. The elements Na and Mg showed the lowest and highest concentrations in the youngest age group (0-19 years), respectively, and reached plateau levels in older age groups. The Ca and P concentrations were highest in the 20-39-year age group, gradually decreasing throughout older age groups, indicating that osteoporotic bone loss occurs in the older subjects. In addition, the results of correlation analysis indicated that the organic matter content of the bone, represented by C or N concentration, was a factor which contributed to the elemental variation of the bone.