Re: LNT and Public Fear

[MCNAUGHT@lanl.gov (Mike McNaughton)]

>If I understand the thrust of your comments, the position is 1)that the
>tools of epidemiology cannot be applied to prove a negative finding or
>absence of phenomenon; and/or 2)epidemology cannot confirm that
>_absolutely_no_ occurence will be manifested below a threshold. 

Are we making the assumption that below a "threshold" the effect is zero?
This would be so if each cause is separate and simply adds to the total.

But if (for example) there are interactions among the various causes of
cancer, e.g. involving stimulation or suppression of the immune system, then
epidemiological studies might conceivably demonstrate a negative slope.  In
this case epidemiology could in theory demonstrate a different sort of
"threshold" below which the net benefit exceeds the detriment.