Abstract Space radiations, especially heavy ions, constitute significant hazards to astronauts. These hazards will increase as space missions lengthen. Moreover, the dangers to astronauts will be enhanced by the persistence, or even the progression, of biological damage throughout their subsequent life spans. To assist in the assessment of risks to astronauts, we are investigating the long-term effects of heavy ions on specific animal tissues. In one study, the eyes of rabbits of various ages were exposed to a single dose of Bragg plateau 20Ne ions (LET∞ ≅ 30 keV/μm). The development of cataracts has shown a pronounced age-related response during the first year after irradiation, and will be followed for two more years. In other studies, mice were exposed to single or fractionated doses of 12C ions (4-cm spread-out Bragg peak; dose-averaged LET∞ = 70–80 keV/μm) or 60Co γ-photons (LET∞ = 0.3 keV/μm). Measurements of the frequency of posterior lens opacification have shown that the tissue sparing observed with dose fractionation of γ-photons was absent when 12C-ion doses were fractionated. Development of posterior lens cataracts was also followed for long periods (up to 21 months) in mice exposed to single doses of Bragg plateau HZE particles (40Ar, 20Ne and 12C ions: LET∞ ≅ 100, 30 and 10 keV/μm, respectively) or 225 kVp X-rays. Based on average cataract levels at the different observation times, the RBE's (RBE = relative biological effectiveness) for the ions were circa 5, 3 and 1–2, respectively, over the range of doses used (0.05–0.9 Gy). Investigations of cataractogenesis are useful for exploring the model of radiation damage proposed by Casarett [1] and by Rubin and Casarett [2] with a tissue not connected directly to the vasculature.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Cataractogenesis from high-LET radiation and the Casarett model


    Beteiligte:
    Cox, A.B. (Autor:in) / Lee, A.C. (Autor:in) / Lett, J.T. (Autor:in) / Ainsworth, E.J. (Autor:in) / Jose, J.G. (Autor:in)

    Erschienen in:

    Erscheinungsdatum :

    1983-01-01


    Format / Umfang :

    9 pages




    Medientyp :

    Aufsatz (Zeitschrift)


    Format :

    Elektronische Ressource


    Sprache :

    Englisch



    Cataractogenesis from high-LET radiation and the Casarett model

    Cox, A. B. / Lee, A. C. / Lett, J. T. et al. | NTRS | 1983


    Helium-ion-induced human cataractogenesis

    Blakely, E.A. / Daftari, I.K. / Meecham, W.J. et al. | Elsevier | 1994


    Helium-ion-induced human cataractogenesis

    Blakely, E. A. / Daftari, I. K. / Meecham, W. J. et al. | NTRS | 1994


    Helium-Ion-Induced Human Cataractogenesis

    Blakely, E.A. | Online Contents | 1994


    Late cataractogenesis in primates and lagomorphs after exposure to particulate radiations

    Cox, A.B. / Lee, A.C. / Williams, G.R. et al. | Elsevier | 1991