Bioenvironmental studies form a background against which all atomic
energy research is conducted. The central objective of the Atomic Energy
Commission’s environmental radiation studies is “to determine the fate
and effect of radionuclides in the environment”. This objective calls
for hundreds of concurrent approaches to the interlocking problems of
the air, the sea, and the land. The AEC alone, through its Division of
Biology and Medicine, is supporting research costing about $75 million a
year, about two-thirds of this amount going to biological and medical
programs at AEC laboratories and the remainder to some 650 individual
contract studies at universities, nonprofit institutions, and commercial
research organizations. Additional programs, large and small, are
supported by foundations or other agencies. Work goes on in other
nations. Many programs are international. Although only a fraction of
this total activity is specifically related to environmental problems,
the concern throughout is with the effect, for good or ill, of
radioactivity on man and his world. It is possible to suggest by example
the lines of inquiry.
[Illustration: _A University of Georgia Research Institute ecologist
studying biological specimens in a controlled environment near the AEC
Savannah River Plant, Aiken, South Carolina._]
The Trinity site in New Mexico, scene of the first atomic detonation in
history, was studied for a number of years after 1945, particularly in
relation to the distribution and effects of residual radioactivity in
the desert environment. In 1963 and 1964 scientists from the University
of Missouri undertook to determine the state of revegetation of the
original atomic bomb crater.
The Nevada Test Site, where nuclear programs have been conducted for a
decade and a half, has invited investigations of revegetation. Project
Sedan, an underground thermonuclear detonation in 1962, established
conditions for one such study. The crater produced by this detonation
was 320 feet deep and 1200 feet in diameter. Vegetation growing within
2500 feet of ground zero was almost completely destroyed, and the
original soil was covered by radioactive throwout. Shrubs as far as 5000
feet away from ground zero were damaged by air blast, and, in the weeks
after the detonation, plants within a two-mile radius were covered by
radioactive sand and silt or by deposits of windblown radioactive dust.
Studies in 1963 by scientists from the University of California at Los
Angeles showed that native plants—Russian thistle and various
annuals—had become well established in the zone around the Sedan crater
where the earth was thrown out. This area had remained barren for less
than a year. Some of the shrubs most severely damaged by the blast, and
exposed to cumulative gamma radiation doses of more than 4000 roentgens,
had produced new growth. Populations of creosote bush, evergreen plants
that in 1962 appeared to have been killed by heavy doses of radiation,
were producing leafy branches in the summer of 1963. These developments
permitted no conclusions, of course, for the possible radiation effects
still needed to be identified. Studies were conducted, for example, of
the effect of deliberately depositing nonradioactive dust on healthy
creosote plants, and comparative studies of other phenomena were made.
Since 1959, ecological studies have been carried forward at the Nevada
site by investigators from Brigham Young University who are interested
in the abundance, seasonal occurrence, and ecological influences
affecting the vertebrate and invertebrate animals in plant communities
of the region. Surveys have been made in areas where nuclear explosions
had obliterated natural ecological relationships and in similar areas
undisturbed by nuclear effects. The investigations are concerned
primarily with desert ecology—with the identification of biotic
communities and of predominant animal species.
Among research programs in marine environments is that initiated in 1963
and 1964 by the University of California’s Institute of Marine Resources
at La Jolla, where studies of marine food chains are conducted by a team
of zoologists, chemists, botanists, and microbiologists. The program
studies the interrelations among organisms at the lower levels of the
food chains and the dynamics of marine phytoplankton cell division,
photosynthesis, and excretion of organic matter as related to
temperature, light intensity, and nutrient conditions. The work is
conceived as a basic study of marine ecology. It is focused, however, on
questions found to be significant in studies of radioactivity in the
sea.
The University of California’s Lawrence Radiation Laboratory has
launched a long-term investigation of the effects of the release of
radionuclides on the biosphere, which encompasses the origins,
transport, and final localization of radionuclides in all types of
organs, tissues, cells, and subcellular constituents. The objective is
“to develop the most complete understanding possible of the potential
hazards to man that arise from the release of nuclear radiation and
radionuclides into the biosphere and to apply this knowledge to the
prevention of damage to living forms...”.
In programs such as these—multiplied by hundreds—the problems are being
attacked.