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UNITED STATES
ATOMIC ENERGY COMMISSION

WASHINGTON, D.C. 20545

 

January 22, 1971

Dr. Joshua Lederberg

Department of Genetics

Stanford University School of Medicine
Palo Alto, California 94304

Dear Josh:

Thanks for the items you sent with your note of a few days ago.
Dr. Seaborg has been very much intrigued by your estimation of
mutational load costs as related to radiation exposures and has
had Charlie Edington and Dean Parker help him with the background.

I think it might be good to have your viewpoint carefully set forth
in B.A.S. My regret is that they did not have the editorial good
sense to try something like that first instead of uncritically
printing the Sternglass claims. They laid themselves open to the
charge that they too are interested only in the sensational. The
attempt to present both sides of the question came only after the
damage had been irreparably done.

One thing troubles me about what I have seen so far of your estimates.
Perhaps we are responsible for that since we have stressed the 170 mrem
limit. In fact, it is not the only limit and it is not the most restric-
tive one which is in force with respect to civilian nuclear power reactors.

Probably the most restrictive regulation is the 0.5r exposure limit at

the power plant boundary. Referring to gaseous effluent Knox (UCRL 72765 -
copy enclosed) has estimated that for the population in a radius of 100 km
around a plant to receive an annual average of 170 mr the exposure rate at
the boundary of the plant must be 100 rads yearly. Since the 170 mrem
standard was derived from the 5r and 0.5r limits (applied to successively
larger populations at risk) lowering it 10 fold should result in a
correspondingly lowered boundary exposure limit. It is this restriction
which would probably put some forms of nuclear power in jeopardy.

You might ask why it is necessary to lower both limits but I think the
last sentence in section 1) of your letter to Miss Tocknell has the
answer to that already implied.
Dr. Joshua Lederberg -2- January 22, 1971

In your section 2) of the Tocknell letter you refer to the possibility of
ecosystem concentration resulting in an unforeseen upset of some sort. I
think you underestimate as have many others what has been done in the line

of research and documentation on this subject. The ecological "concentration!
of a radioisotope of an element is limited by its specific activity which
must be diminished continually in relation to its distance from its source

as it mixes with other sources of the same element.

It is only in special circumstances such as in the Columbia River that

very high ratios of reconcentration can occur. There is an enormous

amount of data on specific activities of many dozens of nuclides in
biological material including all of those that are likely to be of
consequence in plants and animals. The only situations that come to mind
that have presented embarrassingly high concentrations are the combination
in which there is little or no supply of theelement in the supporting
medium or when the food chain is very short. Five of these are very well
known: lLodine to grass -» cow —» human; strontium to grain -» cow —» human;
cesium to lichen -—» caribou -> human; phosphate to Columbia River —» algae —»
duck, iron to water —»algae -» zooplankton —>» small fish —»salmon. All
but one of these have only two or at most three links since neither iodine
nor cesium is incorporated into the plant. Strontium is a problem chiefly
while it is still on vegetation from recent fallout. None of these elements
present any especially difficult problem for nuclear power plants.

I suppose my chief worry is that you may be led to discuss a hypothetical
situation in which a large population is supposed to be exposed to the full
limit of a standard. In fact the regulations as now applied would never
permit that level to rise to more than a percent or less of the limit.
Probably the reason standards are being attacked is that those who first
attacked them were not acquainted with the manner of their application and
have avoided a candid and unbiased look at what the real situation is.

They have created a fight which bystanders are dragged into often without
knowing what the fight is all about either. It is true that there might

be exigencies that would tempt people to push for greater exposures but
that is a problem for the generation that it confronts. It is very unlikely
to confront ours since it is difficult to conceive a situation in which

the workers at a plant would subject themselves to near lethal doses.

The real question that might be debated is to my mind, "given the radiation
standards as promulgated what has been the record of the AEC - which is
charged with enforcing the regulations derived from the standards - in
protecting the public against excessive exposure from civilian nuclear

power plant derived radiation sources. Will these regulations be sufficient
to protect the public in the future?”
Dr. Joshua Lederberg - 3. January 22, 1971

I have dwelt at length on some of the problems associated with attempting
to present a reasonably clear picture to readers of B.A.S. I am not sure
my colleagues would agree with my thoughts and the letter should not be

regarded as "official AEC policy.” I do appreciate your invitation to comment.

Sincerely,

  

vision of Biology and Medicine

Enclosure:
UCRL - 72765