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  1. Issue #1 – The NCRP & ICRP had already changed the concept of threshold before BEAR I was formed. The reason BEAR I was formed because even the general public understood there was no threshold and were pressuring the AEC to stop atmospheric fallout testing. The AEC asked the NAS to convene BEAR I.

    Issue #2 – No one cares about a 60 year old paper which only discussed what was already the scientific consensus.

    Issue #3 & #4 – Is Calabrese trustworthy? Is his problem scientific quality or integrity? Well, since he has a fondness for old papers. Here’s one I like (you can just scroll down to conclusions):


    Issue #5: Calabrese ignores the NCRP and the ICRP, because they don’t fit his agenda.

    1. @Bob Applebaum

      The Rockefeller Foundation asked the AEC to convene BEAR 1, not the AEC. See page 506-507 of http://www.nasonline.org/publications/biographical-memoirs/memoir-pdfs/weaver-warren.pdf

      The country’s newspapers during that time had been persistently asking, “What effects will the atomic age have on the human race?” The public was hopelessly confused by the conflicts of opinion being expressed by people it viewed as qualified specialists. At a meeting of the Board of Trustees of the Rockefeller Foundation in 1954, several members asked whether there was any way in which the foundation could help to clear up the confusion. Consequently, the Board asked one of its members, Detlev W. Bronk, who was at that time president of the National Academy of Sciences, whether the Academy would be willing to address itself to some of the scientific aspects of this question. Would the Academy be willing to carry out a survey of the biological effects of atomic radiation and prepare a report that would set forth the best information then available in a form accessible to seriously concerned citizens?

      After consulting his colleagues at the Academy, Bronk agreed to undertake the study. He appointed six committees: genetics, pathology, meteorology, oceanography, and fisheries, agriculture and food supplies, and disposal and dispersal of radioactive wastes. The first committee was chaired by Weaver, who successfully mediated the opposing positions of the two groups of geneticists who were members of the committee and prepared a report that had their unanimous support. After the first summary report was published in 1956, there was virtual editorial unanimity in the nation’s newspapers that “the report should be read in its entirety to be appreciated: and that it deserved the close attention of all concerned citizens.

    2. @Bob Applebaum

      You wrote:

      The NCRP & ICRP had already changed the concept of threshold before BEAR I was formed.

      Since you have quoted Permissible Dose, I presume you have a copy of the book. You can find the following quote on page 24.

      The ICRP met in April 1956 and agreed to lower its suggested maximum occupational dose from external sources to 5 rems per year for whole-body exposure. The previous recommended level had been 0.3 roentgen per week or 15 per year. The ICRP adopted the adjusted limit to conform with the soon to be published report of the National Academy of Sciences, which urged that radiation exposure be kept as low as possible.

      The NCRP set out similar guidelines in a preliminary statement published in January 1957, and, after some revisions, released in final form in April 1958. Like the ICRP, the American committee was influenced not only by scientific considerations, especially the findings of the National Academy of Sciences, but also by the “public clamor” that had arisen over radiation hazards.

  2. No, the AEC asked the NAS. Weaver may not have known all the details. See “Permissible Dose” by U.S. NRC historian J.S. Walker (have to buy it), which has more details Or this long link, which is light on details:


    1. I have Permissible Dose. It was Walker who did not know all of the details and the background, that is why he said that the AEC’s 1955 request was the start of the process. He apparently did not know about the 1954 request from the RF Board of Trustees and Bronk’s consultation with his colleagues about the feasibility.

      The source I quoted was not written by Weaver, but by Mina Rees, an historian working for the National Academy of Sciences with access to their archive materials.

      J. Samuel Walker is a terrific historian, but he might have missed some sources on this topic.

  3. From 1949, Appendix 2 (about 13 pages into document), section “Permissible Dose”:

    “Since it seems well established that there is no threshold dose for the production of gene mutations by radiation, it follow that strictly speaking that there is no such thing as a tolerance dose when all possible effects on the individual and future generations are included”.


    Everyone recognized no threshold in the early 1940’s. Of course, the SORRY members still can’t recognize it, in 2015.

    1. @Bob Applebaum

      You aren’t paying attention.

      As you point out, “there is no threshold dose for the production of gene mutations by radiation.” That is a statement coming from a single easily identifiable group of people who called themselves eugenicists until that name became unfashionable. One of them, Hermann Muller, began asserting that there was no threshold for radiation doses in 1927 based on experiments where the lowest dose used was 50 rad. His experiments were conducted on FRUIT FLIES a species with a life expectancy of about 21 days.

      What evidence did he have for his “no threshold” assertion based on those experiments?

      The lack of evidence didn’t stop Muller from a 30 year long campaign to attract additional followers. Being awarded the 1946 Nobel Prize, immediately after about 15 years of scientific exile in German, the Soviet Union and Amherst College, did not hurt his sales effort.

      It is not true that everyone recognized “no threshold” in the late 1940s. (The Tri-Partite Conferences took place several years after the end of WWII, not in the early 1940s.) What they grudgingly accepted was the geneticists statements that there was no threshold “from a genetic point of view.” That was not their specialty and they had no reason to suspect Muller. They did not have the benefit of hindsight and 20 years worth of research.

      They did not even know what DNA looked like, much less have any way to measure its stability, its reaction to external sources of energy, or its natural repair mechanisms.

  4. Oh, since you have the book, look at pages 10 & 11…”At least for genetic effects, by the time World War II began most scientists had rejected the earlier consensus that exposure to radiation was biologically innocuous below a certain threshold”.

    BEAR I introduced NOTHING significantly new.

    1. @Bob Applebaum

      There is a little more context to that statement.

      Shortly after its reorganization in 1946, the NCRP [of which Hermann Muller was a member] reassessed its position on radiation exposure levels. Largely, but not solely because of genetic considerations, it abandoned the concept “tolerance dose,” which had suggested that exposure to radiation below the specified limits was generally harmless. The findings of H.J. Muller and other geneticists had indicated that reproductive cells were especially vulnerable to even small amounts of radiation and that mutant genes could be inherited from a parent with no obvious radiation-induced injuries. At least for genetic effects, by the time WWII began, most scientists had rejected the earlier consensus that exposure to radiation was biologically innocuous below a certain threshold.

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