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Edward Lewis and Radioactive Fallout: The Impact of Caltech Biologists on the Debate Over Nuclear Weapons Testing in the 1950s and 60s


Caron, Jennifer (2003) Edward Lewis and Radioactive Fallout: The Impact of Caltech Biologists on the Debate Over Nuclear Weapons Testing in the 1950s and 60s. Senior thesis (Major), California Institute of Technology. doi:10.7907/X9VM-Q970.


The work of Caltech biologists, particularly, Edward Lewis, on leukemia and ionizing radiation transformed the public debate over nuclear weapons testing. The United States began testing hydrogen bombs in 1952, sending radioactive fallout around the globe. Earlier more localized fallout was generated starting in 1945 from tests of atomic weapons at Nevada test sites. The Atomic Energy Commission claimed the tests would not harm human health. Geneticists knew from animal and plant experiments that radiation can cause both illness and gene mutations. They spoke out to warn the policymakers and the public. Edward Lewis used data from four independent populations exposed to radiation to demonstrate that the incidence of leukemia was linearly related to the accumulated dose of radiation. He argued that this implied that leukemia resulted from a somatic gene mutation. Since there was no evidence for the existence of a threshold for the induction of gene mutations down to doses as low as 25 r, there was unlikely to be a threshold for the induction of leukemia. This was the first serious challenge to the concept that there would be a threshold for the induction of cancer by ionizing radiation. Outspoken scientists, including Linus Pauling, used Lewis's risk estimate to inform the public about the danger of nuclear fallout by estimating the number of leukemia deaths that would be caused by the test detonations. In May of 1957 Lewis's analysis of the radiation-induced human leukemia data was published as a lead article in Science magazine. In June he presented it before the Joint Committee on Atomic Energy of the US Congress

Item Type:Thesis (Senior thesis (Major))
Subject Keywords:atomic bomb; Edward Lewis ; Beadle; Brown; Caltech; genetics; Hydrogen bomb; Nobel; Pauling; Sturtevant; World War II
Degree Grantor:California Institute of Technology
Division:Humanities and Social Sciences
Major Option:History and Philosophy of Science
Awards:Frank Teruggi Memorial Award, 2002. Eleanor Searle Prize in Law, Politics, and Institutions, 2001. Don Shepard Award, 2000.
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Kormos-Buchwald, Diana L.
Thesis Committee:
  • None, None
Defense Date:8 January 2003
Record Number:CaltechETD:etd-03292004-111416
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:1190
Deposited By: Imported from ETD-db
Deposited On:02 Apr 2004
Last Modified:10 Feb 2021 23:31

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PDF (LewisandFallout.pdf) - Final Version
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