Thyroid Radiation Doses from Fallout

  • E. B. Lewis


Absorbed doses of radiation from fallout, when averaged over yearly periods and over large numbers of individuals, have usually been assumed to be well below the corresponding doses from natural background sources. Although this assumption may be valid for most body organs, it is unlikely to have been valid for the thyroid glands of the average infant and child in the U.S. The purpose of this note is to point out that for the last few years such thyroids probably have received an annual radiation dose (chiefly, from the beta-rays of radioiodine) that is approximately equal to the annual dose which they receive from natural background radiations.


Weapon Test Annual Dose Natural Back Ground Radiation Annual Radiation Dose Radioiodine Activitie 
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    It should be noted that with the cessation of nuclear weapons testing in November, 1958, human thyroid levels of radioiodine should decline exponentially and by January, 1959, there should no longer have been any appreciable contamination of milk with radioiodine from past weapons tests. The level of radioiodine in cow’s milk may well be the most important index of short-term environmental contamination with fission products whether from weapons tests or other sources [see discussion in Safety Aspects of Nuclear Reactors, ed. C. R. McCullough (New York: D. Van Nostrand Co., 1957), 28].Google Scholar

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© Springer Science+Business Media New York 2004

Authors and Affiliations

  • E. B. Lewis
    • 1
  1. 1.Division of BiologyCalifornia Institute of TechnologyPasadenaUSA

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