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RESIDUAL CONTAMINATION OF PLANTS, ANIMALS, SOIL, AND WATER OF THE MARSHALL ISLANDS ONE YEAR Research and Development Report USNRDL_454
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RESIDUAL CONTAMINATION OF PLANTS, ANIMALS, SOIL, AND WATER OF THE MARSHALL ISLANDS ONE YEAR FOLLOWING OPERATION CASTLE FALL-OUT Research and Development Report USNRDL-454 Effects of Atomic Weapons Chemical Technology Division Biological and Medical Sciences Division Scientific Director Commanding Officer and Director San Francisco 24, California
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The amount and distribution of radioactive material remaining on several atolls and incorporated into the flora and fauna of the Marsh$ll Islands was determined one year after their contamination by fallout from the March I, 1954 nuclear detonation of Operation Castle. Significant amounts of radioactive contamination were found in animals, food plants, water and soil samples. The highest concentrations of internally deposited activity were found in marine specimens taken from the northern Rongelap lagoon. Most of the activity in the marine specimens was contributed by Zrg5-Nbp5 and Ru’06-Rh’ob. No fractionation of Sra9-SrO” occurred in the tissue of the fish analyzed. Residual soil contamination was confined to the top several inches of soil, with movement indicated down to the i, The major radionuclide found in the tissues of land animals and plants was CS’~‘. The island soil and lagoon water were t contaminated principally by the rare earth elements, specimens analyzed was generaily proportional to the external gamma reading in each of the areas.
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The problem was to determine the amount and distribution of radioactive material remaining on several atolls and incorporated into the C flora and fauna of the Marshall Islands one year after their contamination by fallout from the March 1, 1954 nuclear detonation of Operation Significant amounts of Mar shall Is land animals, . highest concentrations of radioactive contamination were found in the food plants, water and soil samples. The internally deposited activity were found in marine specimens taken from the northern Rongelap lagoon. Most of in the marine specimens was contributed by Zr9’-Nb9’ and No fractionation of SrB9-SrW occurred in the tissue of the Residual soil contamination was confined to the top several inches of soil, with movement indicated down to the lens water. The major radionuclide found in the tissues of land animals and plants was Cs13’. The island soil and lagoon water were contaminated principally by the rare earth elements, Ru’06-Rh106 and Zr9’-Nb*. The amount of activity in the specimens analyzed was generally proportional to the external gamma reading in each of the areas.
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This is the final report of the Atoll Resurvey Project. The resurvey was made by this Laboratory together with Applied Fisheries Laboratory of the University of Washington, under the joint sponsorship of the Bureau of Ships and the Atomic Energy Commission, Bureau of Ships Project Number NS 081-001 and Bureau of Medicine and Surgery Project Number NM 006 -015.04, Technical The work was done jointly by the Chemical Technology and the Biological and Medical Sciences Divisions of this
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The following men assisted in the analytical work described in this Sample collection was expedited by the work of the following personnel on field trips: The authors gratefuliy acknowledge who assisted with the preparations for the help of all the individuals the field trips. ‘support during the initial phase of the ( with administrative and logistic Mr. Jarvis Todd assisted in the,preparation of this report.
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ADMINISTRATIVE INFORMATION ......,......... iv CHAPTER 2 GROSS ACTIVITY IN PLANTS, SOIL, CORAL, 2.2.4 Coral, Lagoon-Bottom Silt, and Algae CHAPTER 3 NATURE OF THE RESIDUAL CONTAMINATION ;N PLANTS, SOIL, CORAL, LAGOON-BOTTOM SILT, 3.1 Results and Discussion. ........... CHAPTER 4 INTERNAL CONTAMINATION OF FISH, -MARINE SPECIMENS, AND BIRDS ............. 4.2 Results and Discussion. ...........
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5.1 Results and Discussion. ........... 23 5.1.2 Surveys at Specific Locations. . ... 24 6.2 Comments on Future Work.
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Summary of Gross Beta Activity in Major Plant Foods . Summary of Gross Beta Activity in Miscellaneous Plant Beta Activity in Soil Samples Taken from Exposed Profiles. . Beta Activity in Core Samples of Soil ............ Gross Beta Activity in Coral and Algae. ........... Summary of Gross Beta Activity in gater .......... Summary of Beta and Gamma Activity Concentration in Fish and Marine Invertebrates. ............... 4.2 Distribution of Gross Beta and Gamma Activity in Tissues 4.3 Summary of the Gross Beta and Gamma Activity in Small Fish and Marine Invertebrates. ............... 4.4 Summary of the Gross Beta and Gamma Activity in Birds 4;5 Radiochemical Analysis of Fish and Chicken ......,.. 5.1 Average Gamma-Dose Rates on Islands ........,..
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As a result of a nuclear detonation in Operation CASTLE, several atolls in the Marshall Islands were accidentally contaminated by radioactive fall-out to such an extent that evacuation of the inhabitants was necessary. ’ Plants, animals, water, and soil were collected from the islands one month after the fall-out occurred. The animals not sacrificed at the site were sent to this laboratory and radiochemical analysis was made of their tissues to provide information on the internal radiation hazard. A report’ of this study has been published. As a follow-up to the original ,study 2 iesurvey of the contaminated Marshall Islands was undertaken one year .after the fall-out. Radiochemical analysis of food plants, fish, water, soil, coral, algae, and birds was made to determine the nature and extent of the internal and external radiation hazard created by the residual contamination on the islands. A gamma dose-rate survey was conducted to determine the external radiation hazard extant. Such data were necessary to determine the possibility of re-occupying the islands. The present report presents the data obtained from the resurvey of the contaminated islands. This work was named the Atoll Resurvey Project, entitled llFollowup Determination of the Extent and Distribution of Fal:-out Contaminatipn on Rongelap and Other Atolls in the Marshall Group. ‘I Its specific a. To provide data upon which a decision can be based as to when the evacuated islands may be safely re-occupied by their former inhabb. To provide information about distribution of the residual contamination on a land area which had been heavily contaminated by fall-out.
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-. Significant amounts of beta and gamma activity were found in the tissues of Marshall Island fish and marine invertebrates collected one year following exposure to the fall-out from Operation CASTLE. The highest concentrations of internally deposited activity was found in marine specimens taken from the northern Rongelap lagoon; lower concentrations of internal activity were found in specimens from the southe rn lagoon. The crabs, clams, and snails contained considerably higher concentrations of radionuclides than were found in the fish from the same area. Most of the activit in the marine specimens was contribSr89-Sr90 in the tissue of the fish analyzgd.’ Residual soil contamination was primarily contained in the top several inches of soil with movement indicated down to the lens water. The activity is being slowly leached off the islands by ocean tides. The major radionuclide found in the land food plants and in the tissues of land animais was Cs13’. The lagoon environment contained principally Radioactivity was found in all food plants on the contaminated islands. Supporting plant systems also contained a large reservoir of activity available for future incorporation into the plants. The amount of activity in the specimens analyzed was generally proportional to the external gamma reading in each of the areas. 6.2 COMMENTS ON FUTURE WORK In the event that future work is carried out along the lines initiated during this project the following suggestion may be helpful.
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Sampling of coconut tree sap, pandanus, and breadfruit would be greatly expedited by scheduling the major survey during the end of the rainy season, preferably in November. This would also allow a better study of the effect of rainfall on the leaching of activity from the soil into the lens water and from there into the lagoon or ocean. Studies on the movement of activity into the supporting plant systems might be broadened to forecast the transfer of more hazardous nuclides into reproductive fractions of the plants.
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Cronkite, E. P., et al., Study of Response of Human Beings Accidentally Exposed to Significant Fallout Radiation, Naval Medical Research Institution and Naval Radiological Defense Laboratory, Operation CASTLE Project 4.1 Final Report No. WT-923 Cohn, S. H., et al., Study of the Internal Radioactive Contamination of Human Beings and Animals and Contamination of the Environment Resulting From Fall-out in Operation CASTLE, Naval Medical Research Institution and Naval Radiological Defense Laboratory, Operation CASTLE Project 4.1 Addendum Report No. WT-936, Nucleonics, Vol. 2, No. 5, pp c-2 to.c-1, November 1951.
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dak Ridge, Tennessee 37830 The enclosed material is in response o your telephone request to /7 Ray Oxendine n Dorothy Eldridge Customer Services Division