Probability of cell hits in selected organs and tissues by high-LET particles at the ISS orbit.
The fluence of high-LET particles (HLP) with LET infinity H2O greater than 15 keV micrometers-1 in selected organs and tissues were measured with plastic nuclear track detectors using a life-size human phantom on the 9th Shuttle-Mir Mission (STS-91). The planar-track fluence of HLP during the 9.8-day mission ranged from 1.9 x 10(3) n cm-2 (bladder) to 5.1 x 10(3) n cm-2 (brain) by a factor of 2.7. Based on these data, a probability of HLP hits to a matured cell of each organ or tissue was roughly estimated for a 90-day ISS mission. In the calculation, all cells were assumed to be spheres with a geometric cross-sectional area of 500 micrometers2 and the cell-hit frequency from isotropic space radiation can be described by the Poisson-distribution function. As results, the probability of one or more than 1 hit to a single cell by HLP for 90 days ranged from 17% to 38%; that of two or more than 2 hits was estimated to be 1.3-8.2%.
Yasuda
H
H
National Institute of Radiological Sciences (NIRS), Inage-ku, Chiba, Japan.
Komiyama
T
T
Fujitaka
K
K
D001921:Brain / Q000528:radiation effects; D002477:Cells / Q000528:radiation effects*; D020450:Heavy Ions; D006801:Humans; D018499:Linear Energy Transfer; D019047:Phantoms, Imaging; D011092:Polyethylene Glycols; D011336:Probability; D011829:Radiation Dosage; D011853:Radiobiology; D011874:Radiometry; D013026:Space Flight; D018531:Spacecraft; D013819:Thermoluminescent Dosimetry / Q000295:instrumentation; D001743:Urinary Bladder / Q000528:radiation effects
C028827:CR 39; D011092:Polyethylene Glycols