Michael E. Ketterer

Plutonium is distributed globally in the Earth's surface environment as a result of atmospheric weapons tests, nuclear accidents, and nuclear fuel reprocessing. Mass spectrometry (MS), in particular, sector field ICP-MS, now is used widely to determine Pu activities and isotope ratios; 240Pu/239 is very useful in determining Pu origin. Determination of Pu by ICP-MS involves dissolution, column separation, and the MS determination; detection limits are 0.1–10 fg for each isotope. Applications of the determination of sector field ICP-MS to studies of environmental Pu include discerning sources of contamination near the Chernobyl reactor, and chronology of recent aquatic sediments.