Supported ²⁴²Cm in the marine environment

Abstract

BOWEN and Livingston¹ have reported the presence of ²⁴²Cm (half-life 163 d) in two samples of sea water which had been kept in sealed containers for 12 yr since the time of collection. Because the ²⁴²Cm originally present in the samples would have decayed completely after this period of storage, they suggested that the ²⁴²Cm which they detect is supported by a long-lived precursor, ^242mAm; this radionuclide would not itself be detectable in these samples because of its much longer half-life (152 yr). They invited other workers in radiochemistry to search for similar evidence for ^242mAm in the environment, and we have done so in some samples collected from the vicinity of the fuel-processing plant at Windscale where controlled discharges of transuranic nuclides to the marine environment are permitted under the provisions of the United Kingdom Radioactive Substances Act, 1960. The radiological implications of these discharges have been discussed by Hetherington et al.².