Abstract
The content of plutonium in sea water collected in the western North Pacific off Japan was determined. Plutonium was analyzed by the a-ray spectrometric method after isolating it from a large volume of sea water by hydroxide coprecipitation and an anion exchanger. The plutonium content in sea water ranged from 1.8 to 22.6x 10-15 g/l in the surface waters. Even in the intermediate or deep waters, comparatively high concentration of plutonium was determined. The ratio of 238Pu/289Pu ranged from 7 to 28%.
