THE EXTENT AND CONSEQUENCES OF THE
UPTAKE BY PLANTS OF RADIOACTIVE
NUCLIDES’
By R. Scorr Russet.
Agricultural Research Council Radtobiological Laboratory,
Letcombe Regis, WANTAGE, Berkshire, England
INTRODUCTION
The title of this review was chosen by the Editors, who indicated that
it should be interpreted broadly; discussion should not be limited to problems of plant physiology. There are obvious reasons for this directive. The
wide attention which haslately been given to the entry of radioactive nuclides
into plants is due neither to their role in metabolism nor to their effects on
plant growth; the predominant source of interest is the internal radiation
dose which they may deliver to man. The words “extent” and “consequences” in the present title have little meaning outside this context. Because the biological effects of radiation from all sources are additive, the
significance of the radiation dose which man receives from radioactive
materials which pass through food chains into his diet can be judged in
-
.
perspective only when compared with doses from other sources to which he
is simultaneously exposed. Thefirst part of this review is therefore devoted
to a brief summary of current knowledge on the sources and extent of
radiation to which the population lately has been exposed. This will enable
problems of plant physiology and soil science, which are of major practical
importance, to be selected for subsequent discussion.
This approach should not be regarded as suggesting that the behaviour
of individual radioactive substances in plants is not of considerable plant
physiological interest. Rather it takes account of the fact that, in the terminology of a recent review of the organisation of research, investigations in
this field at the present time can usually be described as “objective basic
research” (1). This term is used in contra-distinction to “pure basic re-
search.” The difference between these two categories lies in that whereas
the latter is pursued solely because of its intrinsic scientific interest, the
former though frequently of equal interest, and equally demanding, in addition provides information which serves a specific practical end, and its
pursuit is planned with this end in view.
SOURCES AND MAGNITUDE OF ENVIRONMENTAL RADIOACTIVITY
Natural sources—Our knowledge of the natural sources of radiation to
which man is exposed has increased considerably in recent years, The sec*The survey of literature pertaining to this review was concluded in October
1962.
271
OTD tees ea oF
AI A
sew ee
~
ae
fee
Be
re ee