Toggle Main Menu Toggle Search

Open Access padlockePrints

Review of relative biological effectiveness dependence on linear energy transfer for low-LET radiations

Lookup NU author(s): Dr Colin Muirhead


Full text for this publication is not currently held within this repository. Alternative links are provided below where available.


Information on Japanese A-bomb survivors exposed to gamma radiation has been used to estimate cancer risks for the whole range of photon (x-rays) and electron energies which are commonly encountered by radiation workers in the work place or by patients and workers in diagnostic radiology. However, there is some uncertainty regarding the radiation effectiveness of various low-linear energy transfer (low-LET) radiations (x-rays, gamma radiation and electrons). In this paper we review information on the effectiveness of low-LET radiations on the basis of epidemiological and in vitro radiobiological studies. Data from various experimental studies for chromosome aberrations and cell transformation in human lymphocytes and from epidemiological studies of the Japanese A-bomb survivors, patients medically exposed to radiation for diagnostic and therapeutic procedures, and occupational exposures of nuclear workers are considered. On the basis of in vitro cellular radiobiology, there is considerable evidence that the relative biological effectiveness (RBE) of high-energy low-LET radiation (gamma radiation, electrons) is less than that of low-energy low-LET radiation (x-rays, betas). This is a factor of about 3 to 4 for 29 kVp x-rays (e.g. as in diagnostic radiation exposures of the female breast) and for tritium beta-rays (encountered in parts of the nuclear industry) relative to Co-60 gamma radiation and 2-5 MeV gamma-rays (as received by the Japanese A-bomb survivors). In epidemiological studies, although for thyroid and breast cancer there appears to be a small tendency for the excess relative risks to decrease as the radiation energy increases for low-LET radiations, it is not statistically feasible to draw any conclusion regarding an underlying dependence of cancer risk on LET for the nominally low-LET radiations.

Publication metadata

Author(s): Hunter N, Muirhead CR

Publication type: Article

Publication status: Published

Journal: Journal of Radiological Protection

Year: 2009

Volume: 29

Issue: 1

Pages: 5-21

Print publication date: 01/03/2009

ISSN (print): 0952-4746

ISSN (electronic): 1361-6498

Publisher: Institute of Physics Publishing Ltd.


DOI: 10.1088/0952-4746/29/1/R01


Altmetrics provided by Altmetric