Re: Krypton-85

[RuthWeiner@AOL.COM]

Kr-85 has a 10.8 year half-life and is a beta (and gamma) emitter.  It is a fission product and the yield of Kr-85 is uranium fission (as in a nuke plant) is significant.  The decay product would be Rb-85, which is stable.  Commoner's concern was quite real and certainly is justified if one buys the LNT.  Krypton is an ideal gas (like radon, only much less likely to be trapped) and does not chemically combine.  Incidentally, the ability of Xenon to form compounds, under certain conditions, was discovered when I was in graduate school, in (I believe) 1961, but those conditions are certainly much more stringent than the conditions found in the ambient evnironment.  Generally, ideal gases would be trapped by van der Waals forces, not even by the weak chemical bonding that binds some molecules to surfaces.  


Back to Commoner: the projections of nuclear power in the late 1970s, coupled with the ideal gas behavior of Kr-85 and its yield in controlled fission, could have been projected at that time to produce significant exposure from skyshine and groundshine.   It is NOT a question of inhalation, but more of groundshine and especially skyshine.  The skyshine dose conversion factor for Kr-85 is significant.  In fact, I believe one might say that the lack of observed health effects from Kr-85 in the atmosphere shows that the LNT does NOT apply.  PLEASE NOTE: that is my speculation alone -- no one has come up with this idea as far as I know (and no, I haven't surfed the web to find out).    



Ruth Weiner, Ph. D.

ruthweiner@aol.com