The Children of Atomic Bomb Survivors A Genetic Study (1991) / Chapter Skim
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Congenital Malformations, Stillbirths, and Early Mortality Among the Children of Atomic Bomb Survivors: A Reanalysis
Congenital Malformations, Stillbirths, and Early Mortality Among the Children of Atomic Bomb Survivors: A Reanalysis
Pages 377-388
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From page 377... ...
A "one-hit" model with appropriate adjustments for extraneous sources of variation results in an almost identical value, namely, 0.00412 (+0.00364~. When the sample is extended to include parents lacking the full array of dose parameters necessary to calculate the DS86 dose, but sufficient for an empirical conversion of the previously employed T65DR dose system to its DS86 equivalent, we find under the linear model that the estimated increase per sievert in untoward pregnancy outcomes is some 31% higher than that published previously, 0.00264 (+0.00277)
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From page 378... ...
Although these changes are diverse, the aim of identifying them is the same- to estimate the probability of mutation per unit exposure to ionizing radiation and to ascertain the public health implications of an increase in the number of mutations. The purpose of this paper is to reexamine one facet of these studies of the offspring of the survivors of the atomic bombing of Hiroshima and Nagasaki: the clinical data on adverse pregnancy outcomes obtained in the years 194853.
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From page 379... ...
It is this latter group, which involves one or both ofthe parents for approximately 14,000 pregnancy terminations, that is the primary focus of the ad hoc doses. The exposure data on these parents were collected between 1948 and 1954 (cf.
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From page 380... ...
If this be so, then the distribution of DS86 doses within the sum groups where both doses are known can be used to provide an ad hoc TABLE IV The Distribution of Joint Parental Gonadal Absorbed Dose Equivalent by City and Dose Category in the Cohort of Births Seen in 1948-1953, Extended (DS86 + ad hoc Dose) Cohorta Dose category (Sv)
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From page 381... ...
, other values for the neutron RBE would not materially alter the results to be described subsequently, for under the DS86 system of dosimetry the neutron contribution is small, and the RBE assigned to neutrons is of minor importance in determining the slope of the dose-response relationship. Statistical Methods In the analysis of untoward pregnancy outcomes, the effects of radiation have been estimated using two overlapping samples of observations.
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From page 382... ...
Based on an Assumed Neutron RBE of 20, Sexes and Cities Combined, DS86 Cohort Only Father's gonadal dose equivalent (Sv) Mother's gonadal dose equivalent (Sv)
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From page 383... ...
Again the regression of untoward pregnancy outcome upon parental radiation ex posure is positive, which would be expected if the exposure had induced deleterious dominant mutations, but the re gression is well below statistical significance, and insignifi cantly lower than that obtained with the DS86 only cohort. Furthermore, none of the components of the untoward pregnancy outcomes gives any hint of responding differen tially to parental radiation (Table X)
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From page 384... ...
Based on an Assumed Neutron RBE of 20, Sexes and Cities Combined, Extended (DS86 + ad hoc Dose) Cohort Father's gonadal dose equivalent (Sv)
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From page 385... ...
With respect to socioeconomic TABLE X Increments or Decrements of Change in the Individual Frequencies of Congenital Malformation, Stillbirths, and Neonatal Deaths in the Original Cohort of Births per Sievert of Joint Parental Gonadal Dose Equivalent Based Upon an Assumed Neutron RBE of 20, Extended (DS86 + ad hoc) Cohort Regression Standard coefficient error Regression model: P
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From page 386... ...
It is important to note that the estimate of genetic damage following exposure to ionizing radiation derived here rests on mutational events manifesting themselves as an untoward pregnancy outcome recognizable between 20 weeks after fertilization and 14 days following birth. Clearly this does not represent all of the mutational damage that could be expressed throughout life or even all of that from fertilization to 14 days postpartum.
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From page 387... ...
L OHARA, Analysis of atomic bomb radiation dose estimation at RERF using data on acute radiation symptoms.
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