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PHYS. MED. BIOL., 1976, VoL. 21, No. 6, 903-919.
© 1976
The Observation and Analysis of Cancer Deaths
among Classified Radiation Workers
J. A. RETSSLAND, vip., aaanst.p., P. KAY, pup., a.r.c.s. and
G. W. DOLPHIN, rim.p., p.sc.
National Radiological Protection Board, Harwell, Oxon, ULI.
Received 29 ALarch 1976, tn final form 5 July 1976
Ausrracr. The extent to which occupational radiation exposure contributes to cancer
mortality is an influence on future world energy policy. It is also a factor in deciding
the level of expenditure to reduce radiation levels expericneed by workers. Here we
discuss some of the difficulties In analysing the situation and present the results of
some calculations which estimate the expected age-specific radiation mortalities from
all inducible cancers and also from leuknemian separately, Using » high vatue for the
average occupational exposure and a conservative estimate of the associated risk, we
find that a survey of molality among radiation workers must run over many years
before sufficient dati would be accumulated to resolve the effects of radiation-induced
neoplasins from those arising from other causes. We show tho advisability: of determining the cause of death both of persons who remain employedin the industry and all
persons who enter and subsequently leavo tho industry, perhaps being employedin it
for only a short time. Our estimates are based on maintenance of an occupationally
exposed dose of one rad per person per year during the period of the survey which may
extend over several decades. However, scaling of the estimates to any other exposure
rates is casily performed.
.
We nlso give estimates of the lowest risk cocllicients delectable in a given observation time. Smee for a work force of 3000 these lowest detectable values ave an outer of
magnitude larger than those expected, it is clear (hat only a national or international
survey can produce dato adequate for even modest objectives.
J.
Introduction
The widespread use of radioactive isotopes, X-ray equipment, neutron
generators and the rate of expansion of the nuclear power industry has raised
questions about the carcinogenic effects of radiation at the levels experienced
by operational workers. We are not concerned in this paper with exposure
resulting from accidents, neither are we concerned with the mechanisms of
carcinogenesis. Our prime objectives here are to assess the prospects of drawing
any conclusions from a survey of causes of death of radiation workers; to
identify the factors which influence these prospects; to estimate the effects of
latency of radiation cffects on the age-specific death rate; and to provide basic
information from which the relative magnitude of vadiation-induced and
natural cancers can be estimated. All of these factors arc relevant considera{ions in the sebling up of a survey. The ultimate value of a survey will be
determined by the information contained within the collected data. Before
establishing the data base it is prudent to attempt to anticipate the demands
which will bo made on it. This paper reports such an atlempe6.
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