The ¹³⁷Cs contents of papers such as magazines and newspapers printed in Japan were determined by gamma-ray spectrometry. The average ¹³⁷Cs content of weekly general interest magazines was 0.95 Bq kg^-1 and far higher than those of other kinds of samples. The result of phloroglucinol color test showed that the main printed pages of the weekly general interest magazines were chiefly made of mechanical pulp. Possibly the pages held ¹³⁷Cs brought by wood, raw material of paper, and that accounted for the high ¹³⁷Cs content of the magazines. The experimental result suggested that ¹³⁷Cs was removed from wood into aqueous solution in the production of chemical pulp. Cesium-137 radioactivity removed during paper manufacturing in the year 2000 in Japan was estimated to be 15 GBq, and the influence of paper manufacturing on the migration of ¹³⁷Cs in the environment was discussed.

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With a combination of a single anion-exchange column and mixed media of CH₃COOH and other acids (HCl and/or HNO₃), 50 ng each of U, Th, Pb, and the lanthanides were sequentially separated. The mixed media including CH₃COOH were effective for the sequential separation. All of the elements were more than 95% recovered, and the decontamination factor was more than 100. Major elements in geological samples such as alkali metals, alkaline earth metals, and Fe were eliminated from the column. This separation technique reduces separation time and simplifies the complicated traditional processes without any special reagents or equipments. The technique has potential for use in pg (10^-12 g) level trace analysis.

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