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RE: Radon and Never Smokers
Chris,
As you suggested I did take a critical look at the study.
Yes, just a few comments.
In the Executive summary below it states, "BEIR VI recommends that the power
of an indoor radon study to detect an excess risk could be enhanced by
targeting special populations, such a population with high exposures, a
broad range of exposures, and low residential mobility. The preferential use
of non-smokers was not recommended."
This sounds like the Iowa Study published last year met this criteria better
than the Schneesberg Study.
I am not aware that the Schneesberg study has been published yet in the peer
reviewed literature. The last mention I have heard about the study is that
it was rejected by the journal Health Physics. There must have been some
problems with the study for them to reject it. Maybe, it is the limited
sample size of the study.
Jim Nelson
>From: "Christoph Hofmeyr" <chofmeyr@nnr.co.za>
>Reply-To: "Christoph Hofmeyr" <chofmeyr@nnr.co.za>
>To: <radsafe@list.vanderbilt.edu>
>Subject: RE: Radon and Never Smokers
>Date: Wed, 27 Jun 2001 16:34:57 +0200
>
>Tom, Jim, Radsafers,
>Why not have a critical look at the www.precura.de website; under
>Publications you can download the Schneeberg study "High residential
>radon health effects in Saxony". There are long-term exposure
>categories from <50 to >1500 Bq/m^3. In Germany the medical records as
>well as the occupational records are relatively reliable. This report
>does not seem to indicate an increased lung cancer risk up to
>residential radon levels of 1000 Bq/m^3, and suggests a reduced relative
>risk between the lowest category and 1000 Bq/m^3. Any comment? I include
>a summary:
>
>""Analysis of the likelihood of female inhabitants of Schneeberg and
>Schlema (Saxony) contracting lung cancer as a result of radon exposure
>in dwellings arising from mining and geologically-induced factors, and
>studies concerning the reconstruction of exposure".
>J. Conrady, K. Martin, A. Poffijn, M. Tirmarche, J. Lembcke, D.M. Thai,
>H. Martin
>Executive Summary
>The available data from indoor radon studies were considered by BEIR VI
>to be not yet sufficient to develop a general risk-assessment model or
>to estimate precisely the magnitude of risk posed by radon in houses. In
>its conclusions, BEIR VI recommends that the power of an indoor radon
>study to detect an excess risk could be enhanced by targeting special
>populations, such a population with high exposures, a broad range of
>exposures, and low residential mobility. The preferential use of
>non-smokers was not recommended. Otherwise the Schneeberg study
>completely complies with BEIR VI recommendations regarding its
>conditions.
>An increased and significant OR could be established with the Schneeberg
>study by two forms of analysis in the higher exposure-categories only.
>Below a radon-concentration of 48 * 106 (Bqh/m³) accordingly 1000 Bq/m³
>and a residential duration of 20 years the OR is not elevated.
>Significantly elevated OR after both forms of the analysis are
>detectable at the exposition level of > 1500 Bq/m³ .
>The risk estimation of the Schneeberg study for lung cancer from indoor
>radon is not in accordance with the results from miners and population
>studies, which state an excess risk for 10%/100 Bq/m³ radon exposure. If
>such risk estimates are true, in the highly exposed population of
>Schneeberg such lung cancer risks must have been easily established.
>That is not the case. From the risk estimate of the Schneeberg study
>even a safe threshold value was found and a significantly elevated risk
>appeared at >1.500 Bq/m³ only. Great efforts were taken to explain such
>discrepancies in comparison to the results from other studies. One
>reason could be the favourable study conditions of the Schneeberg study
>(highly exposed population, mainly non-smoking women, exposed fraction
>very high and a relatively high power etc.). The other reasons are
>related to characteristics of the other studies especially with the low
>exposure to indoor radon and a high exposure to tobacco smoke and a low
>power. The results from the Schneeberg study are on the other hand
>enough founded to make further research in that key population a top
>priority and hesitate to introduce prematurely legal limits for indoor
>radon."
>
>Chris Hofmeyr
>chofmeyr@nnr.co.za
>
>-----Original Message-----
>From: Tom Mohaupt [mailto:tom.mohaupt@WRIGHT.EDU]
>Sent: Tuesday, June 26, 2001 6:27 PM
>To: Jim Nelson; RadSafe
>Subject: Re: Radon and Never Smokers
>
>
>Indeed an interesting study. Thanks Jim for bringing it to our
>attention.
>Some comments:
>
>1) The relative risks presented in Table 5 adjusted with missing data
>imputed. They state the relative risk as 1.55 for radon concentrations
>greater than 140 Bq/m^3. From Table 4, concentrations greater than 200
>Bq/m^3 (with imputed data) give a RR of 1.067 [Cases: 13/258; Controls:
>23/487]. Big difference. New math?
>
>2) Looking over Table 4, there really isn't a discernible difference
>between the cases and controls. Any differences in percentages can
>easily
>be swayed by one or two cases (or controls) improperly grouped.
>
>3) It doesn't look like Sweden has a genuine radon problem. The control
>distribution of radon concentration should represent the country at
>large.
>In such case, less than 5% of the population is exposed to radon
>concentration more than 200 Bq/m^3 (the European action level for new
>construction) and 0.6% of the population is exposed to radon
>concentrations
>more than 400 Bq/m^3 ( the action level for existing structures).
>
>4) I would have liked to see the authors include higher categories of
>radon
>concentrations, such as 800 and 1200 Bq/m^3, since these levels do exist
>and are biologically more important. Using administrative values as data
>cutoff point is OK as long as higher cutoff values are presented for
>comparison (i.e., 400 Bq/m^3 to infinity represents an enormous spectrum
>of
>concentrations).
>
>Tom
>
>
>
>Jim Nelson wrote:
> >
> > Interesting article recently published.
> > http://www.epidem.com/article.asp?ISSN=1044-3983&VOL=12&ISS=4&PAGE=396
> >
> > Residential Radon and Lung Cancer among Never-Smokers in Sweden
> >
> > Frédéric Lagarde1; Gösta Axelsson2; Lena Damber3; Hans Mellander4;
>Fredrik
> > Nyberg1; Göran Pershagen1,5
> >
> > >From the 1Institute of Environmental Medicine, Karolinska Institutet,
> > Stockholm;
> > 2Department of Environmental Medicine, Göteborg University,
>Gothenburg;
> > 3Department of Oncology, University Hospital, Ume;
> > 4Swedish Radiation Protection Institute, Stockholm; and
> > 5Department of Environmental Health, Stockholm County Council,
>Stockholm,
> > Sweden.
> >
> > EPIDEMIOLOGY 2001;12:396-404
> >
> >
>------------------------------------------------------------------------
>--------
> >
> > In this study, we attempted to reduce existing uncertainty about the
> > relative risk of lung cancer from residential radon exposure among
> > never-smokers. Comprehensive measurements of domestic radon were
>performed
> > for 258 never-smoking lung cancer cases and 487 never-smoking controls
>from
> > five Swedish case-control studies. With additional never-smokers from
>a
> > previous case-control study of lung cancer and residential radon
>exposure in
> > Sweden, a total of 436 never-smoking lung cancer cases diagnosed in
>Sweden
> > between 1980 and 1995 and 1,649 never-smoking controls were included.
>The
> > relative risks (with 95% confidence intervals in parentheses) of lung
>cancer
> > in relation to categories of time-weighted average domestic radon
> > concentration during three decades, delimited by cutpoints at 50, 80,
>and
> > 140 Bq m-3, were 1.08 (0.8-1.5), 1.18 (0.9-1.6), and 1.44 (1.0-2.1),
> > respectively, with average radon concentrations below 50 Bq m-3 used
>as
> > reference category and with adjustment for other risk factors. The
>data
> > suggested that among never-smokers residential radon exposure may be
>more
> > harmful for those exposed to environmental tobacco smoke. Overall, an
>excess
> > relative risk of 10% per 100 Bq m-3 average radon concentration was
> > estimated, which is similar to the summary effect estimate for all
>subjects
> > in the main residential radon studies to date.
> >
> > Keywords: case-control study; lung neoplasms; risk assessment; radon;
> > never-smokers; cocarcinogenesis; tobacco smoke pollution;
>environmental
> > exposures
> >
> > _________________________________________________________________
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> >
> >
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>--
>Thomas Mohaupt, M.S., CHP
>University Radiation Safety Officer
>
>104 Health Sciences Bldg
>Wright State University
>Dayton, Ohio 45435
>tom.mohaupt@wright.edu
>(937) 775-2169
>(937) 775-3761 (fax)
>
>"An investment in knowledge gains the best interest." Ben Franklin
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