In order to estimate the availability of zeolite, one of the inorganic ion exchangers, as an eliminator for the incorporated radionuclides, wholebody retention of intraperitoneally administrated 54Mn and 65Zn was measured in mice fed a zeolite-added diet at 10 per cent. Wholebody retention of 54Mn and 65Zn was decreased significantly faster than control, and the biological half-life of them was also reduced to 11.3 and 12.7 days, respectively, from 14.1 and 16.8 days in controls. The results suggest that oral administration of zeolite is effective to eliminate the incorporated 54Mn and 65Zn, and if it is used in combination with the chelation therapy of DTPA, it will be more effective.
