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Title: Radiation doses for Marshall Islands Atolls Affected by U.S. Nuclear Testing:All Exposure Pathways, Remedial Measures, and Environmental Loss of 137Cs

Abstract

The United States conducted 24 nuclear tests at Bikini Atoll with a total yield of 76.8 Megatons (MT). The Castle series produced about 60% of this total and included the Bravo test that was the primary source of contamination of Bikini Island and Rongelap and Utrok Atolls. One of three aerial drops missed the atoll and the second test of the Crossroads series, the Baker test, was an underwater detonation. Of the rest, 17 were on barges on water and 3 were on platforms on an island; they produced most of the contamination of islands at the atoll. There were 42 tests conducted at Enewetak Atoll with a total yield of 31.7 MT (Simon and Robison, 1997; UNSCEAR, 2000). Of these tests, 18 were on a barge over wateror reef, 7 were surface shots, 2 aerial drops, 2 under water detonations, and 13 tower shots on either land or reef. All produced some contamination of various atoll islands. Rongelap Atoll received radioactive fallout as a result of the Bravo test on March 1, 1954 that was part of the Castle series of tests. This deposition was the result of the Bravo test producing a yield of 15 MT, about amore » factor of three to four greater than the predicted yield that resulted in vaporization of more coral reef and island than expected and in the debris-cloud reaching a much higher altitude than anticipated. High-altitude winds were to the east at the time of detonation and carried the debris-cloud toward Rongelap Atoll. Utrok Atoll also received fallout from the Bravo test but at much lower air and ground-level concentrations than at Rongelap atoll. Other atolls received Bravo fallout at levels below that of Utrok [other common spellings of this island and atoll (Simon, et al., 2009)]. To avoid confusion in reading other literature, this atoll and island are spelled in a variety of ways (Utrik, Utirik, Uterik or Utrok). Dose assessments for Bikini Island at Bikini Atoll (Robison et al., 1997), Enjebi Island at Enewetak Atoll (Robison et al., 1987), Rongelap Island at Rongelap Atoll (Robison et al., 1994; Simon et al., 1997), and Utrok Island at Utrok Atoll (Robison, et al., 1999) indicate that about 95-99% of the total estimated dose to people who may return to live at the atolls today (Utrok Island is populated) is the result of exposure to {sup 137}Cs. External gamma exposure from {sup 137}Cs in the soil accounts for about 10 to 15% of the total dose and {sup 137}Cs ingested during consumption of local food crops such as drinking coconut meat and fluid (Cocos nucifera L.), copra meat and milk, Pandanus fruit, and breadfruit accounts for about 85 to 90%. The other 1 to 2% of the estimated dose is from {sup 90}Sr, {sup 239+240}Pu, and {sup 241}Am. The {sup 90}Sr exposure is primarily through the food chain while the exposure to {sup 239+240}Pu, and {sup 241}Am is primarily via the inhalation pathway as a result of breathing re-suspended soil particles.« less

Authors:
;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
970676
Report Number(s):
LLNL-JRNL-412571
Journal ID: ISSN 0017-9078; HLTPAO; TRN: US201003%%41
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Journal Article
Journal Name:
Health Physics
Additional Journal Information:
Journal Volume: 98; Journal Issue: 1; Journal ID: ISSN 0017-9078
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; ALTITUDE; COCONUTS; CONTAMINATION; CROPS; DEPOSITION; ENIWETOK; EVAPORATION; EXPLOSIONS; FALLOUT; FOOD; FOOD CHAINS; GROUND LEVEL; INHALATION; ISLANDS; MARSHALL ISLANDS; RADIATION DOSES; RESPIRATION; SOILS; TESTING; WATER

Citation Formats

Robison, W L, and Hamilton, T F. Radiation doses for Marshall Islands Atolls Affected by U.S. Nuclear Testing:All Exposure Pathways, Remedial Measures, and Environmental Loss of 137Cs. United States: N. p., 2009. Web.
Robison, W L, & Hamilton, T F. Radiation doses for Marshall Islands Atolls Affected by U.S. Nuclear Testing:All Exposure Pathways, Remedial Measures, and Environmental Loss of 137Cs. United States.
Robison, W L, and Hamilton, T F. 2009. "Radiation doses for Marshall Islands Atolls Affected by U.S. Nuclear Testing:All Exposure Pathways, Remedial Measures, and Environmental Loss of 137Cs". United States. https://www.osti.gov/servlets/purl/970676.
@article{osti_970676,
title = {Radiation doses for Marshall Islands Atolls Affected by U.S. Nuclear Testing:All Exposure Pathways, Remedial Measures, and Environmental Loss of 137Cs},
author = {Robison, W L and Hamilton, T F},
abstractNote = {The United States conducted 24 nuclear tests at Bikini Atoll with a total yield of 76.8 Megatons (MT). The Castle series produced about 60% of this total and included the Bravo test that was the primary source of contamination of Bikini Island and Rongelap and Utrok Atolls. One of three aerial drops missed the atoll and the second test of the Crossroads series, the Baker test, was an underwater detonation. Of the rest, 17 were on barges on water and 3 were on platforms on an island; they produced most of the contamination of islands at the atoll. There were 42 tests conducted at Enewetak Atoll with a total yield of 31.7 MT (Simon and Robison, 1997; UNSCEAR, 2000). Of these tests, 18 were on a barge over wateror reef, 7 were surface shots, 2 aerial drops, 2 under water detonations, and 13 tower shots on either land or reef. All produced some contamination of various atoll islands. Rongelap Atoll received radioactive fallout as a result of the Bravo test on March 1, 1954 that was part of the Castle series of tests. This deposition was the result of the Bravo test producing a yield of 15 MT, about a factor of three to four greater than the predicted yield that resulted in vaporization of more coral reef and island than expected and in the debris-cloud reaching a much higher altitude than anticipated. High-altitude winds were to the east at the time of detonation and carried the debris-cloud toward Rongelap Atoll. Utrok Atoll also received fallout from the Bravo test but at much lower air and ground-level concentrations than at Rongelap atoll. Other atolls received Bravo fallout at levels below that of Utrok [other common spellings of this island and atoll (Simon, et al., 2009)]. To avoid confusion in reading other literature, this atoll and island are spelled in a variety of ways (Utrik, Utirik, Uterik or Utrok). Dose assessments for Bikini Island at Bikini Atoll (Robison et al., 1997), Enjebi Island at Enewetak Atoll (Robison et al., 1987), Rongelap Island at Rongelap Atoll (Robison et al., 1994; Simon et al., 1997), and Utrok Island at Utrok Atoll (Robison, et al., 1999) indicate that about 95-99% of the total estimated dose to people who may return to live at the atolls today (Utrok Island is populated) is the result of exposure to {sup 137}Cs. External gamma exposure from {sup 137}Cs in the soil accounts for about 10 to 15% of the total dose and {sup 137}Cs ingested during consumption of local food crops such as drinking coconut meat and fluid (Cocos nucifera L.), copra meat and milk, Pandanus fruit, and breadfruit accounts for about 85 to 90%. The other 1 to 2% of the estimated dose is from {sup 90}Sr, {sup 239+240}Pu, and {sup 241}Am. The {sup 90}Sr exposure is primarily through the food chain while the exposure to {sup 239+240}Pu, and {sup 241}Am is primarily via the inhalation pathway as a result of breathing re-suspended soil particles.},
doi = {},
url = {https://www.osti.gov/biblio/970676}, journal = {Health Physics},
issn = {0017-9078},
number = 1,
volume = 98,
place = {United States},
year = {Mon Apr 20 00:00:00 EDT 2009},
month = {Mon Apr 20 00:00:00 EDT 2009}
}