Re: Linear, no-threshold <hwade@aol.com>

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

Our studies show little difference in radon levels for those 
who did "much","little", or "nothing" to reduce heat loss; the ratio of 
radon levels for these was 1.02,0.92,1.00 respectively (Cohen, Hlth Phys 
60.634; 1991). I assume that this was because the principal thing was 
adding insulation which does not affect radon levels. The questionaire 
specifically suggested "weatherstripping, closing gaps under doors, 
sealing windows, etc", but that's how the results came out.
	In any case, such an effect would only change absolute radon levels 
leaving relative radon levels for various counties less affected. Of 
course this effect would be more important in case-control studies 
because having a lung cancer death in a house would encourage people
to do something about ventilation. None of the case-control studies 
investigate this matter.
 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, 16 Jan 1996, Bob Flood wrote:

>  He raises the issue that the measurements were made after the cancer deaths 
> >occurred. This, of course, is a real problem with the case-control 
> >studies that Strom thinks so highly of. But it is much less of a problem 
> >with my studies, which require only that the average radon levels in a 
> >county measured in different time periods are strongly correlated.
> 
> A question, then, about the time dependence (if any) for indoor radon
> concentrations: The oil embargo in the 1973-74 time frame and the increase
> in home heating/cooling costs resulted in a substantial interest in improved
> home insulation. Changes were made in many homes (perhaps a majority of
> homes?) ranging from door or window weather-stripping to full wall and
> celing insulation. It seems (at an intuitive level) that indoor radon levels
> in the 50's, 60's, and early 70's would have been lower than in the 80's.
> This has the potential to lead the observer to compare cancer rates from a
> lower radon exposure period to radon concentrations made higher in response
> to increased energy costs. Has this potential discontinuity been addressed?
> 
> BTW, I am one of those doubting the LNT model.
> Bob Flood
> Unless otherwise noted, all opinions are mine alone.
> (415) 926-3793
> bflood@slac.stanford.edu
>