The relevance of dose for low-energy beta emitters
- 18 August 2009
- journal article
- review article
- Published by IOP Publishing in Journal of Radiological Protection
- Vol. 29 (3), 321-333
- https://doi.org/10.1088/0952-4746/29/3/s01
Abstract
Specific issues in risk assessment for low-energy beta emitters include specification of the radiation weighting factor, values of relative biological effectiveness for specific or accurate risk estimates, non-uniformities of dose within tissues and cells, and use of standard tissue weighting factors for non-uniform situations. Unusual features of low-energy beta emitters include: increased average ionisation density on subcellular (and cellular) scales; short ranges of the beta electrons; non-uniformity of the absorbed dose over subcellular, cellular, and tissue dimensions; reduced hit frequencies; nuclear transmutations; different chemical forms, influencing biokinetics and dose distributions; and large isotopic mass differences, particularly in the case of tritium and hydrogen. Many of these features are not included explicitly in conventional radiation protection dosimetry, although they may be partly included in experimental determinations of relative biological effectiveness. Theoretical and experimental studies have shown low-energy electrons to be particularly efficient in producing double-strand breaks in DNA, including complex double-strand breaks. Hence, on fundamental grounds, tritium beta particles should be expected to have greater biological effectiveness per unit absorbed dose than 60Co gamma-rays or orthovoltage x-rays. For practical purposes, and in view of the paucity of epidemiological estimates of risk from low-energy electrons, consideration should be given to applying a raised relative biological effectiveness, say of value 2, to all low-energy internal emitters, including beta particles and soft x-ray emissions.Keywords
This publication has 16 references indexed in Scilit:
- Internal dosimetry and tritium—the ICRP positionJournal of Radiological Protection, 2008
- Energy deposition stochastics and track structure: what about the target?Radiation Protection Dosimetry, 2006
- Radiation quality of tritiumRadiation Protection Dosimetry, 2006
- Non-exchangeable organically bound tritium (OBT): its real natureAnalytical and Bioanalytical Chemistry, 2004
- Dependence of the Yield of DNA Double-Strand Breaks in Chinese Hamster V79-4 Cells on the Photon Energy of Ultrasoft X RaysRadiation Research, 2001
- Initial Events in the Cellular Effects of Ionizing Radiations: Clustered Damage in DNAInternational Journal of Radiation Biology, 1994
- Current Status of Ultrasoft X Rays and Track Structure Analysis as Tools for Testing and Developing Biophysical Models of Radiation ActionRadiation Protection Dosimetry, 1990
- Relationship of Microdosimetric Techniques to Applications in Biological SystemsPublished by Elsevier BV ,1987
- Low-dose RBE and Q for X-ray Compared to Gamma-ray RadiationsHealth Physics, 1978
- Some Physical Aspects of Relative Biological EfficiencyThe British Journal of Radiology, 1957