CONTENTS 



Page 



I. INTRODUCTION 1 



11. GENERAL NATURE AND PRESENT STATUS 2 



in. PHYSICAL AND RADIOLOGICAL CONSIDERATIONS 3 



IV. SPECIAL PROBLEMS 4 



A. Localization of Radiation 4 



B. Transmutation 4 



C. Relative Biological Effectiveness (RBE) 5 



V. MODES OF ENTRY INTO ANIMALS AND MAN 6 



A. Ingestion 6 



B. Inhalation "7 



C. Skin Absorption 7 



VI. EFFECTS OF RADIONUCLIDES AFTER ABSORPTION 8 



A. Acute and Subacute Effects 8 



B. Chronic Effects 8 



Vn. CONSIDERATION OF PARTICULAR RADIONUCLIDES 10 



A. The Alkaline Earths (Calcium, Strontium, 



Barium, Radium) 10 



1. Radium-226 10 



2. Radiostrontium 11 



B. The Lanthanide and Actinide Rare Earths 



(Including Yttrium) 12 



C. Cesium-137 12 



D. Iodine-131 13 



E. Other Radionuclides 13 



1. Ruthenium- 106, Ruthenium- 103 13 



2. Zinc-65 14 



3. Other Minor Radionuclides 14 



F. General Considerations 14 



VIII. MAXIMUM PERMISSIBLE EXPOSURE (MPE) LEVELS 



FOR RADIOACTIVE MATERIALS 16 



IX. CURRENT AND RECOMMENDED RESEARCH 18 



X. CONCLUSIONS 20 



XI. REFERENCES 21 



V 



