title: Age dependence of natural uranium and thorium concentrations in bone.
abstract: The age dependence of the natural concentration of uranium and thorium in the skeleton was investigated using human vertebrae bone collected from two Canadian locations (Winnipeg, Manitoba, and Regina, Saskatchewan). The concentration of both radioelements in digested ashed bone samples was determined using sector-field inductively coupled plasma mass spectrometry. The geometric means for uranium level in bones showed a significant statistical difference between the two locations studied. Similarly for thorium, a statistical difference was observed, although this difference was considered marginal. The thorium concentration differed only marginally with respect to age group, indicating that its behavior in the body could be age-independent. Conversely, the uranium level in bones was found to change for the age groups tested, an indication of age-specific deposition. The age profile for uranium was comparable to the calcium turn-over rate, indicating that uranium deposition is probably, in part, dictated by this metabolic process, showing the role of present uptake into the uranium concentration in bones for populations exposed to significant uranium intake.
authors.affiliation: Radiation Protection Bureau, Health Canada, 775 Brookfield Road, Address Locator 6302D1, Ottawa, ON, Canada, K1A. dominic_lariviere@hc-sc.gc.ca
authors.forename: Dominic
authors.initials: D
authors.lastname: Larivière
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Packer
authors.forename: Leonora
authors.initials: L
authors.lastname: Marro
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: R Jack
authors.initials: RJ
authors.lastname: Cornett
mesh_terms: D000375:Aging; D001417:Background Radiation; D001822:Body Burden; D001842:Bone and Bones / Q000737:chemistry*; D002170:Canada; D006801:Humans; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D012062:Relative Biological Effectiveness; D013910:Thorium / Q000032:analysis*; D014501:Uranium / Q000032:analysis*
chemical_list: D014501:Uranium; D013910:Thorium