Skin dose from neutron-activated soil for early entrants following the A-bomb detonation in Hiroshima: contribution from β and γ rays

Tanaka, Kenichi; Endo, Satoru; Imanaka, Tadayuki; Shizuma, Kiyoshi; Hasai, Hiromi; Hoshi, Masaharu

doi:10.1007/s00411-008-0172-1

Cited by 19 publications

(29 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Unlike systemic exposure to direct radiation by neutrons and gamma rays from the atomic bombs, residual radioactivity would have involved radioactive material in the surrounding environment of the survivor and would have resulted in different exposure modalities. Examples include contact skin dose from fallout that may have been in rain, or beta dose to skin occurring after the end of rainfall from fallout on the ground or other surfaces in the environment, or external exposure from neutron-activated soil materials nearby or adhering to skin (16,17).…”

Section: Discussionmentioning

confidence: 99%

“…Also, a small sample of Nishiyama and non-exposed residents were tested for radiological body burdens in 1970 and higher 137 Cs counts were observed among the Nishiyama residents. Radiation dose to the skin from fission fallout and neutron-activated soil has been previously estimated based on the following assumptions in Hiroshima (16,17). Endo et al calculated that if the skin was covered with a 26 lm thick layer of soil contaminated with a fallout radionuclide inventory corresponding to an initial ground deposition of 1 kBq/m 2 -137 Cs, the total beta dose to skin would be about 0.5 Sv for continuous exposure over the one-month period after the explosion (16).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Association of Acute Radiation Syndrome and Rain after the Bombings in Atomic Bomb Survivors

Ozasa¹,

Sakata²,

Cullings

et al. 2016

Radiation Research

View full text Add to dashboard Cite

Acute radiation-induced symptoms reported in survivors after the atomic bombings in Hiroshima and Nagasaki have been suspected to be associated with rain that fell after the explosions, but this association has not been evaluated in an epidemiological study that considers the effects of the direct dose from the atomic bombs and other factors. The aim of this study was to evaluate this association using information from a fixed cohort, comprised of 93,741 members of the Life Span Study who were in the city at the time of the bombing. Information on acute symptoms and exposure to rain was collected in surveys conducted by interviewers, primarily in the 1950s. The proportion of survivors developing severe epilation was around 60% at levels of direct radiation doses of 3 Gy or higher and less than 0.2% at levels <0.005 Gy regardless of reported rain exposure status. The low prevalence of acute symptoms at low direct doses indicates that the reported fallout rain was not homogeneously radioactive at a level sufficient to cause a substantial probability of acute symptoms. We observed that the proportion of reported acute symptoms was slightly higher among those who reported rain exposure in some subgroups, however, suggestions that rain was the cause of these reported symptoms are not supported by analyses specific to the known areas of radioactive fallout. Misclassification of exposure and outcome, including symptoms due to other causes and recall bias, appears to be a more plausible explanation. However, the insufficient and retrospective nature of the available data limited our ability to quantify the attribution to those possible causes.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Association of Acute Radiation Syndrome and Rain after the Bombings in Atomic Bomb Survivors

Ozasa¹,

Sakata²,

Cullings

et al. 2016

Radiation Research

View full text Add to dashboard Cite

show abstract

“…Both from the ABCC/RERF data and other reports, there is no consistent and convincing evidence of a particular directional asymmetry in rates of epilation among distal survivors. It was observed that Culling's 50th-percentile dose estimate for epilation is 2 Gy with an assumed neutron dose weight of 1, significantly less than a 3-Gy threshold described below or the 2-Gy threshold mentioned by Tanaka et al (2008).…”

Section: Survivors Who Experienced Epilation and Their Locationsmentioning

confidence: 92%

“…Monte Carlo simulation of electron transport in biological tissue was performed using MCNP-4C code with the EL03 Library of cross sections for electrons, and beta spectra of different neutron-activated radionuclides were accounted for. Using the standing Japanese human phantom, the cumulative beta dose to the skin of the head approached approximately 0.1 Gy, compared with 0.2 Gy in Tanaka et al (2008) for skin on a vertical surface of the torso at the Hiroshima hypocenter.…”

Section: Estimation Of Contact Beta-particle Exposures To Residual Ramentioning

confidence: 99%

Workshop Report on Atomic Bomb Dosimetry—Review of Dose Related Factors for the Evaluation of Exposures to Residual Radiation at Hiroshima and Nagasaki

et al. 2015

Self Cite

View full text Add to dashboard Cite

Groups of Japanese and American scientists, supported by international collaborators, have worked for many years to ensure the accuracy of the radiation dosimetry used in studies of health effects in the Japanese atomic bomb survivors. Reliable dosimetric models and systems are especially critical to epidemiologic studies of this population because of their importance in the development of worldwide radiation protection standards. While dosimetry systems, such as Dosimetry System 1986 (DS86) and Dosimetry System 2002 (DS02), have improved, the research groups that developed them were unable to propose or confirm an additional contribution by residual radiation to the survivor's total body dose. In recognition of the need for an up-to-date review of residual radiation exposures in Hiroshima and Nagasaki, a half-day technical session was held for reports on newer studies at the 59 th Annual HPS Meeting in 2014 in Baltimore, MD. A day-and-a-half workshop was also held to provide time for detailed discussion of the newer studies and to evaluate their potential use in clarifying the residual radiation exposure to atomic bomb survivors at Hiroshima and Nagasaki. The process also involved a re-examination of very early surveys of radioisotope emissions from ground surfaces at Hiroshima and Nagasaki and early reports of health effects. New insights were reported on the potential contribution to residual radiation from neutron-activated radionuclides in the airburst's dust stem and pedestal and in unlofted soil, as well as from fission products and weapon debris from the nuclear cloud. However, disparate views remain concerning the actual residual radiation doses received by the atomic bomb survivors at different distances from the hypocenter. The workshop discussion indicated that measurements made using thermal luminescence and optically stimulated luminescence, like earlier measurements, especially in very thin layers of the samples, could be expanded to detect possible radiation exposures to beta particles and to determine their significance plus the extent of the various residual radiation areas at Hiroshima and Nagasaki. Other suggestions for future residual radiation studies are included in this workshop report.

show abstract

“…Also, activated materials may be likely to have the energy from betas be less than from gamma rays. Tanaka et al (2008) calculated a small skin dose at Hiroshima, for example 0.37 Gy if the hypocenter area is occupied for 7 days after entering 1 h after the bombing. However, only activated soil was considered by Tanaka.…”

Section: Interpreting Excess Tld Dosementioning

confidence: 99%

Gamma-ray thermoluminescence measurements: a record of fallout deposition in Hiroshima?

Egbert

Kerr

2012

Radiat Environ Biophys

View full text Add to dashboard Cite

In certain Hiroshima neighborhoods, radiation measurements using thermoluminescence dosimetry (TLD) exceed what can be explained by the initial gamma-ray doses and uncertainties from the Dosimetry System 2002 (DS02). This problem was not previously recognized as being isolated to certain parts of that city. The ratio between TLD measurements and DS02 dose calculations for gamma rays appear to grow larger than unity up to more than three with increasing ground range, but closer examination shows the excess TLD dose (0.1, 0.2, or possibly up to 0.8 Gray) is correlated with certain neighborhoods and could be due to radioactive fallout. At Nagasaki, the TLD measurements do not show this same excess, probably because there were no TLD measurements taken more than 800 m downwind (eastward) from the Nagasaki hypocenter, so that any small excess TLD dose was masked by larger initial gamma-ray doses of 25-80 Gray in the few downwind samples. The DS02 Report had noted many measurements lower than the DS02 calculation for several Nagasaki TLD samples, independent of ground range. This was explained as being the result of previously unaccounted urban shielding which was observed from Nagasaki pre-bomb aerial photos. However, the Hiroshima excess TLD dose issue was not resolved. If the excess TLD doses at Hiroshima are an indication of fallout, it may be possible to use additional TLD studies to make better estimates of the locations and radiation doses to survivors from the fallout after the bombings at both cities.

show abstract

Skin dose from neutron-activated soil for early entrants following the A-bomb detonation in Hiroshima: contribution from β and γ rays

Cited by 19 publications

References 10 publications

Association of Acute Radiation Syndrome and Rain after the Bombings in Atomic Bomb Survivors

Association of Acute Radiation Syndrome and Rain after the Bombings in Atomic Bomb Survivors

Workshop Report on Atomic Bomb Dosimetry—Review of Dose Related Factors for the Evaluation of Exposures to Residual Radiation at Hiroshima and Nagasaki

Gamma-ray thermoluminescence measurements: a record of fallout deposition in Hiroshima?

Contact Info

Product

Resources

About