Radiation Protection Dosimetry 104:337-346 (2003)
© 2003 Oxford University Press
Relative implications of protective responses versus damage induction at low dose and low-dose-rate exposures, using the microdose approach
In reviewing tissue effects of low-dose radiation (1) absorbed dose to tissue is replaced by the sum of energy deposited with track events in cell-equivalent tissue micromasses, i.e. with microdose hits, in the number of exposed micromasses and (2) induced cell damage and adaptive protection are related to microdose hits in exposed micromasses for a given radiation quality. DNA damage increases with the number of microdose hits. They also can induce adaptive protection, mainly against endogenous DNA damage. This protection involves cellular defenses, DNA repair and damage removal. With increasing numbers of low linear energy transfer (LET) microdose hits in exposed micromasses, adaptive protection first tends to outweigh damage and then (above 200 mGy) fails and largely disappears. These experimental data predict that cancer risk coefficients derived by epidemiology at high-dose irradiation decline at low doses and dose rates when adaptive protection outdoes DNA damage. The dose-risk function should include both linear and non-linear terms at low doses.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
G. Sgouros, S. J. Knox, M. C. Joiner, W. F. Morgan, and A. I. Kassis MIRD Continuing Education: Bystander and Low Dose-Rate Effects: Are These Relevant to Radionuclide Therapy? J. Nucl. Med., October 1, 2007; 48(10): 1683 - 1691. [Abstract] [Full Text] [PDF] |
||||
![]() |
C J Martin Effective dose: how should it be applied to medical exposures? Br. J. Radiol., August 1, 2007; 80(956): 639 - 647. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. E. Leonard Adaptive response by single cell radiation hits--implications for nuclear workers Radiat Prot Dosimetry, December 20, 2005; 116(1-4): 387 - 391. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. E. Feinendegen and R. D. Neumann Physics must join with biology in better assessing risk from low-dose irradiation Radiat Prot Dosimetry, December 1, 2005; 117(4): 346 - 356. [Abstract] [Full Text] [PDF] |
||||
![]() |
L E Feinendegen Evidence for beneficial low level radiation effects and radiation hormesis Br. J. Radiol., January 1, 2005; 78(925): 3 - 7. [Abstract] [Full Text] [PDF] |
||||
![]() |
L E Feinendegen Significance of basic and clinical research in radiation medicine: challenges for the future Br. J. Radiol., January 1, 2005; Supplement_27(1): 185 - 195. [Abstract] [Full Text] [PDF] |
||||


