ATTACHMENT 1 

January 5, 1944: Glenn Seaborg to Robert Stone (1 p.)

January 5, 1944

R. E. Stone
G. T. Seaborg

Physiological Hazards of Working with Plutonium

It has occurred to me that the physiological hazards of 
(ILLEGIBLE) with plutonium and its compounds may be very great. 
Due to the alpha radiation and long life it may be that the 
permanent location in the body of even very small amounts, say 
one milligram or less, may be very harmful. The ingestion of such 
extraordinarily small amounts as some few tens of micrograms might 
be unpleasant, in its locates itself in a permanent position. In the 
handlings of the relatively large amounts soon to begin here and 
at Site Y, there are many conceivable methods by which amounts of 
this order might be taken in unless the greatest care is 
exercised.

In addition to helping to set up safety measures in (ILLEGIBLE) so as 
to prevent the occurrence of such accidents, I would like to suggest 
that a program to trace the course of plutonium in the body be 
initiated as soon as possible. In my opinion such a program should 
have the very highest priority.

GTS:RES
c/c to S. K. Allison
A. H. Compton
T. R. Hogness
Central Reading File