64 or others with 10 or 15 micrograms had relatively little 2 changes. 3 into consideration as far as permissible levels are 4 iB q 16/1000ths of one per cent of the radium excreted per day. 8 This is a factor adfour to eight when you estimate permissiblp 9 body burdens of radium compared to the more accurate I $8 ra] 13 to keep these factors in consideration, that there is a ge 14 marked biological variation, and also a marked biological 15 elimination of these elements. 16 the near permissible range, I think these people are extremelp 17 important from a long term study, because we know away above 18 this we are going to get tumors and away below we are not 19 going to worry. a 20 21 22 23 ARC 24 25 Tag ei Qenartes Le Hise * permissible levels, think it is very important as far as the humans are concerned 5 ‘ So when we talk in terms of 12 & mo ~ estimates by measurements. 8° | ‘ The other thing is that the excretion studies done by Norris in Chicago, there was a finding of 2000ths to 11 = concerned. 6 10 e This is a factor of 10 or 15, which must be taken OY: WY ~ 7 a ae bacgacaed ey ent moe % This is Since these elements are in the range which we are interested in} - I think these people are extremely important from a long term study in that respect. I an not familiar with all the radio elements there that are of biological and physical half lives. I think Tomorrow I will take the information and refer it to the studies of the people with the late effects, if that is agreeable.