Re: Background radiation and cancer

[Phil Rutherford <pdrutherford@earthlink.net>]

Paul Lavely wrote:
> 
> We have been involved in public meetings regarding radiation and cancer.
> One group has stated that up to 15 percent of ALL human cancers are from
> "background radiation" (their definition excludes ALL man-made sources -
> including medical). Does anyone know the source for a quote such as this?
> 
> Thanks very much for your help.
>_______________________________________________________________


I generally use a figure of 0.0004 lifetime cancer risk per rem (from an
NRC Reg. Guide

which is based on BEIR V risk data). Assuming 0.3 rem/year background
(excluding medical sources), a 75 year average lifetime, AND ASSUMING
THE LINEAR NO THREASHOLD (LNT) MODEL, this gives a lifetime cancer risk
from background radiation of ...



	0.0004 x 0.3 x 75 = 0.9%



This may be compared to California Cancer Registry data which gives ...



	cancer mortality per lifetime = 11%

	cancer morbidity (incidence) per lifetime = 27%



I believe the 0.0004 per rem risk number from NRC is lifetime mortality
risk, in which case one could compare 0.9% to 11% and conclude that,
ASSUMING THE LNT MODEL, background radiation causes 8% of all cancer
deaths.

Although I havn't worked the numbers, this is presumeably the basis for
the EPA assertions for radon induced lung cancer deaths.



One last point.  Morgenstern, Hirsch and Stewart of "Rocketdyne Worker
Health Study" fame would have us believe that low level radiation
exposure is 6 to 8 times more "deadly" then previously thought from
A-bomb survivor data (i.e. BEIR V).  Using this "profound new finding"
plus the BEIR V and LNT results above, one must conclude that the cancer
mortality risk from background radiation is actually ...

	0.9% x (6 to 8) = 5.4% to 7.2%

Thus, when compared to the 11% cancer lifetime mortality rate, one must
conclude that background radiation is responsible for 50% to 65% of all
cancers.  The anti-nukes are digging themselves into a hole with the
illogicality of there own conclusions. Or maybe they really do believe
that essentially all cancer is caused by background radiation??? At this
rate they will be putting out of business all those epidemiologists and
cancer researchers who are making their careers studying the other
causes of cancer including genetics, environmental pollution, diet,
lifestyle, aging, etc. etc.


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These are clearly my own views. 
___________________________________________________________



Phil Rutherford

Manager, Radiation Safety

Rocketdyne Propulsion & Power

Boeing Space Systems

6633 Canoga Ave

P.O. Box 7922, MS T487

Canoga Park, CA 91309-7922



Tel:       (818) 586-6140

Fax:       (818) 586-2190



E-mail:     philip.d.rutherford@boeing.com  (work)

            pdrutherford@earthlink.net      (home)

            

Web Sites:  http://home.earthlink.net/~pdrutherford/  (home)

            http://www.boeing.com/space/rdyne/        (work)

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