Protocol for X-ray dosimetry EULEP. Report

Directorate-General For Research And Innovation

Sujets

• Sciences et techniques

Informations

• Publié par: DIRECTORATE-GENERAL-FOR-RESEARCH-AND-INNOVATION
• Nombre de lectures: 28
• EAN13: 928254575
• Langue: English
• Poids de l'ouvrage: 2 Mo

Extrait

Commission of the European Communities
radiation protection
Report
EUR 9507 EN Commission of the European Communities
radiation protection
Protocol for X-ray dosimetry
EULEP
J. Zoetelief, J.J. Broerse
Radiobiological Institute TNO
PO Box 5815
2280 HV Rijswijk
The Netherlands
R.W. Davies
Amersham International PLC
White Lion Road
Amersham, Bucks. HP7 9LL
United Kingdom
Contract No BIO-390-81 F
Directorate-General
Science, Research and Development
1985 EUR 9507 EN Published by the
COMMISSION OF THE EUROPEAN COMMUNITIES
Directorate-General
Information Market and Innovation
Bâtiment Jean Monnet
LUXEMBOURG
LEGAL NOTICE
Neither the Commission of the European Communities nor any person acting on
behalf of then is responsible for the use which might be made of the
following information
Cataloguing data can be found at the end of this publication
Luxembourg, Office for Official Publications of the European Communities, 1985
ISBN 92-825-4575-X Catalogue number:
© ECSC-EEC-EAEC, Brussels · Luxembourg, 1985
Printed in Belgium ABSTRACT
To asses the risks of the applications of ionizing radiation in tech­
nology, diagnostic radiology and cancer therapy, information should be
collected on the late effects of accidental or planned exposures.
For this purpose, a number of European laboratories working on stochas­
tic and non-stochastic effects in experimental animals established an ef­
fective cooperation within the European Late Effects Project group
(EULEP), since 1970. A prerequisite for the exchange of biological re­
sults is the standardization of basic experimental techniques including
quality control of the experimental animals, pathology and dosimetry.
To assist the EULEP laboratories, various committees were established
including the committee for dosimetry of external irradiation. This com­
mittee initiated several activities including dosimetry intercomparisons
and site visits to assist participating institutes in resolving specific do­
simetry problems.
The present protocol is an updated version of the 1972 edition and
is intended to serve as a manual for X-ray dosimetry and exposure
arrangements for radiobiological studies in small experimental animals. It
includes recommendations on irradiation conditions, dosimetry methods,
characteristics of phantoms and factors affecting X-ray dosimetry. X-
irradiation procedures employed by the participating institutes are des­
cribed and the results of five X-ray dosimetry intercomparisons are re­
ported. The EULEP code of practice has already resulted in improve­
ments in exposure arrangements and absolute dosimetry.
This project was partly supported by the Committee of the Euro­
pean Communities under contract no. BI0-390-D
1 2 1
J. Zoetelief , R.W. Davies and J.J. Broerse
Radiobiological Institute TNO1, P.O. Box 5815, 2280 HV Rijswijk, The
Netherlands.
2
Formerly, Physics and Radiobiology Department , Medical College of St.
Bartholomew's Hospital, Charterhouse Square, London, Great Britain.
Present address: Amersham International pic, White Lion Road,
Amersham, Buckinghamshire HP7 9LL, Great Britain.
- Ill -EULEP PROTOCOL FOR X-RAY DOSIMETRY AND EXPOSURE ARRANGEMENTS
Table of contents
1. Introduction !
2. Radiation quantities and units 3
3. Requirements for precision and accuracy of absorbed dose
determinations and for homogeneity of dose distributions 8
4. Irradiation conditions 8
5. EULEP code of practice for X irradiations of small animals
18 (e.g. rats and mice)
6. Acknowledgements 22
Supplement I Absorbed dose determinations with ionization chambers 23 t II Other dosimetry methods including TLD 29
Supplement III Measurement of the half value layer (HVL) 41 t IV Animal phantoms for radiobiological dosimetry5
Supplement V Influence of scattering on the absorbed dose distribution
in a mouse phantom: Monte Carlo simulation studies 53
Supplement VI Examples of exposure arrangements and dosimetry
procedures at institutes participating within EULEP 59
Supplement VII The need for dosimetry intercomparisons: conclusions
from EULEP studies 71
Supplement VIII Factors affecting X-ray dosimetry for radiobiology and
some associated pitfalls4
Supplement IX Some dosimetric and radiobiological aspects of partial body
irradiation for late effect studies in rodents 81
Supplement X Interface dosimetry 89
References 95
Rijswijk - London, May 1984
J. Zoetelief, R.W. Davies and J.J. Broerse
- V 1. Introduction
A prerequisite for the coordination of radiobiological research pro­
grams - including those on late somatic effects of ionizing radiation in
mammalian organisms as carried out within the European Late Effects Pro­
ject Group (EULEP) - is the standardization of basic experimental tech­
niques such as exposure arrangements and dosimetry, pathology and the
quality of experimental animals.
The objectives of dosimetry and dose specification range from inci­
dental estimates of the amount of radiation delivered, to the precise spe­
cification of absorbed dose, its macroscopic and microscopic distributions
and other quantities required in the testing of radiobiological theories
(ICRU, 1979a). It is evident that experimental techniques and the
required dosimetric accuracy vary greatly depending on the phenomena
investigated, and that decisions on these matters must be left to the
experimenter. However, the planning of an experiment and the choice of a
method of measuring and reporting dosimetric parameters should follow
certain general principles to ensure that an optimum amount of information
is made available. Complete specification of dosimetric parameters may be
quite important to an individual wishing to use (reported) data in an
attempt to establish correlations or to test a hypothesis, and neither in­
sufficient dose specifications nor uncertainties with respect to accuracy
should limit such efforts.
The problem of dosimetry has to be considered as an essential part
of experimental design before radiobiological experiments are started. If
individuals other than the ones planning thes are to carry out
the dosimetry and the design of the irradiation arrangement, they should
be consulted early, since often seemingly minor modifications in the
irradiation circumstances may result in simplified and more accurate
dosimetry and dose delivery. Except for studies designed to explore their
effects, arrangements yielding complex or unusual radiation patterns
should be avoided. In the case of X rays this situation occurs e.g., when
very high or very low filtration is employed, or when micro-organisms are
irradiated in direct contact with material or medium of high atomic
number, such as glass (see, supplement X).
To assist the EULEP laboratories, a committee for dosimetry of ex­
ternal irradiation has been established (see, Table 1). This committee Table 1
M_e_mbers_of_the_EU_LEP_Xjir_aj/_dosim
M.W. Aarnoudse, Laboratory for Radiopathology, State University
Groningen, Groningen, The Netherlands.
A.L. Batchelor, MRC Radiobiology Unit, Harwell, Great Britain.
J.J. Broerse, chairman. Radiobiological Institute TNO, Rijswijk, The
Netherlands.
A.M. Dancewicz, Institute of Nuclear Research, Department of Radiobio­
logy, Warszawa, Poland.
R.W. Davies, vice­chairman. Formerly, Physics and Radiobiology Depart­
ment, Medical College of St. Bartholomew's Hospital, London. Present
address: Amersham International pic, Amersham, Great Britain.
J.F. Duplan, Institut National de la Santé et de la Récherche Médicale,
Fondation Bergonié, Bordeaux, France
A. Dixon­Brown, Research Institute, The Churchill Hospital, Headington,
Oxford, Great Britain.
Y. Gunn, Research Institute, The Churchill Hospital, Headington, Oxford
Great Britain.
E.B. Harriss, Abt. f. Klinische Physiologie und Arbeitsmedizin der
Universität Ulm, Ulm, Fed. Rep. of Germany.
G.H. Hofmeester , Laboratory for Radiation Research RIVM, Bilthoven,
The Netherlands.
G. Mattelin, Département de Radiobiologie, C.Ε.Ν./S.C.Κ., Mol, Belgium.
W. Müller, Institut f. Biologie, Gesellschaft f. Strahlen­ und Umwelt­
forschung, Neuherberg, Fed. Rep. of Germany.
G. Scarpa, Division of Physics and Biomidical Siences, ENEA, CRE,
Casaccia Roma AD, Italy.
G. Walinder, Unit of Radiological Oncology, University of Stockholm,
Sundbyberg, Sweden.
J. Zoetelief, secretary, Radiobiological Institute TNO, Rijswijk, The
Netherlands.
deceased, September 1983, succeeded by A.H.L. Aalbers