Chapter X 



CONCLUSIONS 



Previous evaluations and conclusions of this Subcommittee have been incorporated 

 in the 1956 and 1960 reports of the Committee on Pathologic Effects of Atomic Radia- 

 tion-^''*. While much new information pertinent to the toxicity of internal emitters has 

 been and is being collected, we feel that, in the light of present knowledge of the sub- 

 ject, the basic principles stated before continue to express our present evaluation of 

 the problem. 



We would emphasize that while progress in such a field as this is necessarily- 

 slow, a number of new trends in research will favor eventual acquisition of data that 

 are necessary for solution of many problems. Among these are (1) the establishment 

 of experimental colonies of large animals, (2) the development of highly sensitive 

 techniques for estimating total body content of radionuclides, and (3) the exploitation 

 of population studies in groups of persons having various degrees of exposure above 

 the average for mankind. 



Certain basic areas of information are also being sought and this will add greatly 

 to the interpretation of empirical data. Studies of the precise localization of deposited 

 radionuclides are progressing along with further investigation of the biological and 

 pathologic importance of localization in terms of the significance of radiation dose rate 

 and of quality of radioactive emission. These may be expected not only to ensure 

 progress in the more practical areas of radiation protection, but to add greatly to 

 our store of knowledge of the nature and etiology of various pathologic processes, 

 including the development of malignant disease. 



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