DISCUSSION 283 



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DISCUSSION 

 Barron : 



I had no intention of taking part in this discussion. However, at the sugges- 

 tion of Eyring, I will re-emphasize the role of oxygen in ionizing radiations, 

 inasmuch as under normal conditions biological fluids are constantly saturated 

 with oxygen. It is well known that the formation of H2O2 on irradiation of water 

 with x-rays occurs only when oxygen is present. Furthermore, the atomic hy- 

 drogen, formed on the primary ionization of water, may reduce molecular oxygen 



