[ RadSafe ] Radon and Lung Cancer

[Wesley]

Dear Otto, Bernie and Radsafe,

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

In this paper I plot the county average lung cancer rate vs. the elevation
above sea level (altitude) and show an inverse association between county
average lung cancer rate and elevation. I postulate that the decrease in
lung cancer rates with higher elevations is caused by the carcinogenic
effect of higher absolute oxygen concentration in the inspired air at lower
elevations. Stratifying Cohen's lung cancer vs. radon data into ten groups
of counties with similar elevations removes some, but not all, of his
inverse association between radon and lung cancer.

This correction for the confounding effects of altitude produces more of a
"flat line" relationship between radon and lung cancer.... i.e., no
association between ambient indoor radon levels and lung cancer. 

Those who are convinced that ambient indoor radon causes lung cancer have
not, in my opinion, satisfactorily explained away Prof. Cohen's study.

Best regards,
Wes
Wesley R. Van Pelt, PhD, CIH, CHP
Wesley R. Van Pelt Associates, Inc.
 
-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf
Of Otto Raabe
Sent: Monday, February 12, 2007 12:02 PM
To: Bernard L. Cohen
Cc: 'RADSAFE'
Subject: Re: [ RadSafe ] Re: Differences in Background radiation and disease
incidence

At 08:28 AM 2/12/2007, Bernard L. Cohen wrote:
>          ---The problem is that the "powers that be" refuse to consider 
> such evidence. My radon study does what you say with tremendous 
> statistical accuracy, and it treats over 500 potential confounding 
> factors, and does a lot of other things with no statistical uncertainty, 
> but it is ignored. They refuse to even consider an ecological study and 
> they ignore all the evidence I have presented.
>>**********************************

February 12, 2007

I believe that Prof. Cohen's studies provide the most reliable available 
information about radon risk to the general public because they are based 
on appropriate dosimetry. In his studies he used overall average 
radon-in-home measurements in each U.S. County as a surrogate for relative 
lifetime average alpha radiation dose rate to the respiratory tract for 
people living in each County. It is the LIFETIME average alpha radiation 
dose rate to the lung that needs to be considered in estimating the risk 
from radon in homes.

In contrast, the case-control studies of indoor radon such as are presented 
in BEIR VI (e.g. Figure G-1, page 377) use selected isolated measurements 
of radon concentration in each individual's home for each case or control 
and there is no way that these measurements can properly represent the 
LIFETIME average alpha radiation dose rate to the lung of any individual in 
contrast to other selected individuals. In addition, the resulting widely 
variable results are used to assign a risk relative to ZERO lifetime alpha 
radiation dose to the lung even though there is not one single person in 
the study whose lifetime dose is zero. Then, with these totally imprecise 
surrogate estimates of lung dose for specific individuals, a regression 
analysis is performed fitting these imprecise data to a log-linear (in the 
case of Figure G-1) or linear function beginning at zero dose. I think the 
results of these types of studies are inherently unreliable.

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
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