Long-Term Effects of Radiation Exposure and the Issue of Reproduction

           The fear of the long-lasting effects of radiation on individual health isolated hibakusha (atomic bomb survivors) as people doomed to continue suffering from the horrors of the atomic bombs as the rest of Japanese society worked to move forward. Such fears were not completely unfounded; in recent years, a study has elaborated on the initial “Life Span Study” of hibakusha, which began in 1950 and worked to chronicle and compile data on how atomic bomb survivors’ quality of life was affected by radiation exposure in the decades following the war. This study factors in data from what it dubs as “missing doses,” or individuals who were not included in the initial study. The majority of these missing doses were within 2 km of the bombing epicenter, an area in which the likelihood and intensity of radiation exposure was higher than areas further away. It was shown that missing doses had a higher adjusted cancer mortality rate, a higher rate of leukemia, and a higher overall mortality rate than those originally included in the Life Span Study.[1] This provides scientific evidence for what many feared at the time; namely, that increased dosages of radiation did increase an individual’s likelihood for developing and dying from cancer, a disease born of genetic mutations in cells.

            In addition to this genetic warping of the adult individuals, radiation’s mutagenic potential presented a chilling prospect for the unborn children exposed to the bombs’ massive quantities of radiation in the womb. A report compiled by the U.S. Atomic Energy commission showed that 13.3% and 4.4% of women in Hiroshima experienced an abortion or had a premature live birth, respectively, while in Nagasaki 22.0% had abortions and 7.3% had premature live births.[2] In the aftermath of the atomic bombs, it would be natural for people to attribute these pregnancy problems with exposure to radiation; however, as this same study mentions, the stress from displacement caused by the bomb could have induced these same effects in expectant mothers. At the time, there was no way in which to conclusively prove the degree to which radiation could affect the unborn children of hibakusha.

            However, to address these failings, later studies have examined the health effects on children exposed to radiation in the womb in Hiroshima and Nagasaki. When testing the intelligence of children who were exposed in the womb and survived until at least 1960, researchers noted that the developing human brain is indeed highly susceptible to radiation, as there was an increased level of severe mental retardation observed among these children.[3] Such effects could be readily observed by hibakusha and other Japanese citizens and attributed to radiation exposure.  As the mechanism for which radiation caused this damage was unknown at the time, hibakusha often lived in fear of radiation damage rearing its ugly head in the bodies of their offspring. This was not limited to children that were in the womb and exposed to radiation; there was also a prevailing paranoia over a parent’s, particularly a mother’s, radiation exposure in Hiroshima or Nagasaki leading to health complications of their children conceived after the fact. An example of this is found in the story of Junko, the young daughter of a hibakusha mother who suddenly fell ill one day in 1966. Immediately, both the mother and hibakusha aunt assume that it was her mother’s experience in Hiroshima that led to the girl’s illness. The doctor assures them that the two cannot possibly be connected, as Junko’s condition is similar to several other cases in different regions of Japan and is therefore unlikely to be radiation related.[4] Nonetheless, this initial reaction is telling; in the minds of many hibakusha, the taint of the atomic bomb can be passed onto the survivors’ children.


[1] Cole, Stephen R., Wing, Steve, and Richardson, David B. “Missing Doses in the Life Span Study of Japanese Atomic Bomb Survivors.” American Journal of Epidemiology 177, no. 6 (2013): 562-568.

[2] United States Atomic Energy Commission, Schneider, B. Aubrey, Rosenbaum, Jack D, Barnett, Henry L, Hammond, E. Cuyler, Liebow, Averill A, Leroy, George V, Oughterson, Ashley W, and the Armed Forces Institute of Pathology. Statistical Analysis of the Medical Effects of the Atomic Bombs: From the Report of the Joint Commission for the Investigation of the Effects of the Atomic Bomb in Japan. 1955.

[3] Schull, William J. “The Somatic Effects of Exposure to Atomic Radiation: The Japanese Experience, 1947-1997.” Proceedings of the National Academy of Sciences of the United States of America 95, no. 10 (1998): 5437-5441,

[4] Sekimori, Gaynor., and Shōno, Naomi. Hibakusha, Survivors of Hiroshima and Nagasaki / Translated by Gaynor Sekimori ; with a Foreword by George Marshall ; and an Introduction by Naomi Shohno. 1st English ed. Tokyo: Kōsei Pub., 1986, 154.