RE: Puskin article[Scanned]

["Dr Christoph Hofmeyr" <chofmeyr@nnr.co.za>]

Hi, all,

About the Puskin paper: very interesting, but I decided against hasty comment.  Interested persons should read prof Cohen's detailed response on his website.



I found a more instructive presentation of Cohen's radon data if one orders the counties according to average radon level from 1 to 1600, i.e. plot against 'rank' from smallest to largest, rather than against radon level on a linear scale, as any dependence on high radon would stand out like a sore thumb (the average concentration doubles between rank 1400 and 1600). Lung cancer mortality shows a beautiful ~linear negative slope against 'rank' with no inflection where the county radon levels shoot up (between 1400 and 1600). Only where Cohen tried to deduce smoking prevalence from the lung cancer rates, does smoking show a clear negative dependence on radon rank.  Where he used other methods, any correlation seems absent or very weak negative.  Most other variables used by Cohen show no obvious correlation against radon 'rank'.  I was postulating that age might be a culprit due to the very strong age dependence of cancer.  However, this also drew a blank.  So the plot thickens.  I conclude from the above plot that a doubling of the relevant radon levels between ~3 and 6 pCi/L (high end) most probably has a zero effect on lung cancer mortality.   This contradicts the linear regressions used by Cohen or Puskin in that concentration range, which are clearly dominated by the lower concentration range up to about 3 pCi/L. Interesting?  Own musings.



Chris Hofmeyr

chofmeyr@nnr.co.za

  



-----Original Message-----

From: Michael G. Stabin [mailto:michael.g.stabin@vanderbilt.edu]

Sent: 24 April 2003 12:48

To: radsafe

Cc: radprot@mad.scientist.com

Subject: Puskin article[Scanned]







The following posted at the request of Don Miller. Mr. Miller is not a

listmember, but he can be contacted directly at the email address shown at

the end of the message.





> -----------------------------------------------

> After reading the Radsafe Archives, I was wondering if Dr.Cohen sent out

either the $1,000.00 or $2,500 reward for this in response to this paper

that more than meets the criteria (as can be found in the archives) for his

reward?

>

> Health Phys 2003 Apr;84(4):526-32 ..

>

> Smoking as a confounder in ecologic correlations of cancer mortality rates

with average county radon levels.

>

> Puskin JS.

>

> Office of Radiation and Indoor Air, U.S. EPA, Washington, DC 20460, USA.

puskin.jerome@epa.gov

>

> Cohen has reported a negative correlation between lung cancer mortality

and average radon levels by county. In this paper, the correlation of U.S.

county mortality rates for various types of cancers during the period

1970-1994 with Cohen's radon measurements is examined. In general,

quantitatively similar, strongly negative correlations are found for cancers

strongly linked to cigarette smoking, weaker negative correlations are found

for cancers moderately increased by smoking, whereas no such correlation is

found for cancers not linked to smoking. The results indicate that the

negative trend previously reported for lung cancer can be largely accounted

for by a negative correlation between smoking and radon levels across

counties. Hence, the observed ecological correlation provides no substantial

evidence for a protective effect of low level radon exposure.

>

> Don Miller

> radprot@mad.scientist.com

>





************************************************************************

You are currently subscribed to the Radsafe mailing list. To unsubscribe,

send an e-mail to Majordomo@list.vanderbilt.edu  Put the text "unsubscribe

radsafe" (no quote marks) in the body of the e-mail, with no subject line.

You can view the Radsafe archives at http://www.vanderbilt.edu/radsafe/