Re: Alpha radiation as tests of LNT

[Bernard L Cohen <blc+@pitt.edu>]

	According to most theories, linear - no threshold should be more 
valid for alpha particles than for beta or gamma rays because it is much 
more likely that a single alpha particle can provide the two hits 
required. For beta and gamma, two separate particles providing the two 
hits might be more important, in which case you would get a quadratic 
rather than a linear response. The reason failures are reported for 
alphas is that they are much easier to detect: according to linear -no 
threshold, natural background gamma rays are responsible for only 1% of 
all cancers, but radon in homes is responsible for 10% of all lung 
cancers. Also, radon in homes is very much more variable than natural 
gamma ray background.

Bernard L. Cohen
Physics Dept.
University of Pittsburgh
Pittsburgh, PA 15260
Tel: (412)624-9245
Fax: (412)624-9163
e-mail: blc+@pitt.edu


On Tue, 30 Jul 1996, David Scherer wrote:

> Thanks to David Gooden for helping to broaden public awareness of this question.
> 
> I have a question for those who follow these studies much more closely than
> I.  From what I read on radsafe, the purported failures of LNT seems to show
> up in studies involving alpha emitting nuclides (e.g., Rn and Ra).  Could
> the problem be that the risk coefficient for high LET radiation (i.e. the Q
> factor)?  Or perhaps only this kind of radiation shows a non-linear response?
> 
> I look forward to your insights.
> 
> Dave Scherer
> scherer@uiuc.edu
>