Measurement of Pu-240/Pu-239 isotopic ratios in soils from the Marshall Islands using ICP-MS

Nuclear weapons tests conducted by the United States in the Marshall Island s produced significant quantities of regional or tropospheric fallout conta mination. Here we report on some preliminary inductively coupled plasma-mas s spectrometry (ICP-MS) measurements of plutonium isolated from seven compo site soil samples collected from Bikini, Enewetak and Rongelap Atolls in th e northern Marshall Islands. These data show that Pu-240/Pu-239 isotopic si gnatures in surface soils from the Marshall Island vary significantly and c ould potentially be used to help quantify the range and extent of fallout d eposition (and associated impacts) from specific weapons tests. Cs-137 and Co-60 were also determined on the same set of soil samples for comparative purposes. (C) 2001 Elsevier Science B.V. All rights reserved.