Internal dosimetry for inhalation of hafnium tritide aerosols.
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.
Inkret
W C
WC
Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Schillaci
M E
ME
Boyce
M K
MK
Cheng
Y S
YS
Efurd
D W
DW
Little
T T
TT
Miller
G
G
Musgrave
J A
JA
Wermer
J R
JR
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
D000336:Aerosols; D014316:Tritium; D006195:Hafnium