[Induced radioactivities in treatment head of 10 MV X-ray linear Accelerator (author's transl)]

The concentration of 60Co and stable cobalt in the shellfishes and seaweeds which were collected from the coast around Japan were obtained by low background beta counting for 60Co and spectrometric determination of stable cobalt. The results obtained were as follows: (1) The 60Co was found in the shellfishes which were enriched in the stable cobalt. (2) The correlation between 60Co and stable cobalt was rather good in the shellfishes. (3) The activities of 60Co was found in the seaweeds taken from seashore near the nuclear power plant. (4) There was great differences in the specific activities between samples collected from contaminated and not contaminated area.