title: Internal dosimetry for inhalation of hafnium tritide aerosols.
abstract: Metal tritides with low dissolution rates may have residence times in the lungs which are considerably longer than the biological half-time normally associated with tritium in body water, resulting in long-term irradiation of the lungs by low energy beta particles and bremsstrahlung X rays. Samples of hafnium tritide were placed in a lung simulant fluid to determine approximate lung dissolution rates. Hafnium hydride samples were analysed for particle size distribution with a scanning electron microscope. Lung simulant data indicated a biological dissolution half-time for hafnium tritide on the order of 10(5) d. Hafnium hydride particle sizes ranged between 2 and 10 microns, corresponding to activity median aerodynamic diameters of 5 to 25 microns. Review of in vitro dissolution data, development of a biokinetic model, and determination of secondary limits for 1 micron AMAD particles are presented and discussed.
authors.affiliation: Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
authors.forename: W C
authors.initials: WC
authors.lastname: Inkret
authors.forename: M E
authors.initials: ME
authors.lastname: Schillaci
authors.forename: M K
authors.initials: MK
authors.lastname: Boyce
authors.forename: Y S
authors.initials: YS
authors.lastname: Cheng
authors.forename: D W
authors.initials: DW
authors.lastname: Efurd
authors.forename: T T
authors.initials: TT
authors.lastname: Little
authors.forename: G
authors.initials: G
authors.lastname: Miller
authors.forename: J A
authors.initials: JA
authors.lastname: Musgrave
authors.forename: J R
authors.initials: JR
authors.lastname: Wermer
mesh_terms: D000336:Aerosols; D006195:Hafnium / Q000032:analysis* / Q000493:pharmacokinetics; D006801:Humans; D019570:Inhalation Exposure; D008168:Lung / Q000528:radiation effects*; D008855:Microscopy, Electron, Scanning; D008954:Models, Biological; D008962:Models, Theoretical; D010316:Particle Size; D011829:Radiation Dosage; D014316:Tritium / Q000032:analysis* / Q000493:pharmacokinetics
chemical_list: D000336:Aerosols; D014316:Tritium; D006195:Hafnium