[ RadSafe ] RE: Radon and Lung Cancer

[Wesley]

Dear Otto,

 

Let me now address the more difficult issue of causation. That is, given the
decrease in county level average lung cancer with both altitude and county
average radon concentration, what is the cause?  It is not enough to just
conclude from Cohen's work that LNT does not work. The lung cancer rate
differences by county must be caused by something. (Epidemiologists might
argue with this statement.)  I believe you and Prof. Cohen would have to
conclude that increased radon somehow reduces the lung cancer rate. How?
Presumably the radiation from radon stimulates the immune system to fight
off the lung cancer. (Sorry for the broad brush radiobiology here!)
However, radon dose rate is primarily high LET alpha radiation. Everything I
know about radiation hormesis indicates low LET and low dose rate radiation
is effective in stimulating the immune system. Are you saying that high LET
alpha dose has a net hormetic effect for lung cancer?  On the other hand,
oxygen tension, for reasons detailed in my paper, is a plausible biological
cause.

Best regards,

Wes

Wesley R. Van Pelt, PhD, CIH, CHP

 <http://mysite.verizon.net/wesvanpelt/index.html> Wesley R. Van Pelt
Associates, Inc.

  _____  

From: Otto Raabe [mailto:ograabe at ucdavis.edu] 
Sent: Tuesday, February 13, 2007 8:29 PM
To: Wesley; 'RADSAFE'
Cc: 'Bernard L. Cohen'
Subject: Re: Radon and Lung Cancer

 

At 08:36 AM 2/13/2007, Wesley wrote:



I would like to remind you of my paper in Health Physics (October 2003):
EPIDEMIOLOGICAL ASSOCIATIONS AMONG LUNG CANCER, RADON EXPOSURE AND ELEVATION
ABOVE SEA LEVEL - A REASSESSMENT OF COHEN'S COUNTY LEVEL RADON STUDY

****************************
Dear Wes, 

I believe that the cellular oxygen tension is about the same no matter what
altitude you reside. If you grow up at high altitude you will develop bigger
more efficient lungs, If you move to a higher altitude you will have an
increase in red-blood cell concentration. In any case, at the cellular level
there will be about the same biologically balanced oxygen tension. No
radiation effects are expected.

There is a general correlation between higher radon and altitude.  That is
somewhat of a coincidence.  There is also an inverse correlation between
latitude and oxygen concentration. A mathematical regression will treat
decreased oxygen and increased radon as somewhat mathematically correlated
even though they are not related, but decreased oxygen is not necessarily a
causative factor in this relationship. It is just a partial surrogate for
increased radon.

When Prof. Cohen evaluated just the former Confederate (southern) States
where there are few high altitude Counties, he got the same inverse
relationship as for the whole nation. Therefore, I concluded altitude is not
a directly important factor in the inverse radon -lung cancer relationship.

Otto
**********************************************
Prof. Otto G. Raabe, Ph.D., CHP
Center for Health & the Environment
University of California
One Shields Avenue
Davis, CA 95616
E-Mail: ograabe at ucdavis.edu
Phone: (530) 752-7754   FAX: (530) 758-6140
***********************************************