RADIATION-INDUCED BONE TUMOURS 159 



lameeton: This is a very good question and we would very much like to be able to 

 compare the plutonium and ^^P and X-ray experiments on a basis of dose. Wo have done 

 a certain amount of tliick-section autoradiography in order to look at some aspects of 

 tills problem but we have to recognize that we don't really know what we mean by dose 

 with alpha emitters. With alpha radiation you are getting relatively few cells given a very 

 high dose whereas with X-rays and ^-rays you are getting a very large majority of cells 

 given a much smaller dose. This is just one of the problems. The other is of course that the 

 range of the alpha emitters is only 30-40 [x, and in which cells are we to calculate 

 the dose? 



