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Re: A question of statistical significance vs operational significance
Bill,
The Missouri I study was negative for lung cancer in nonsmoking women.
Alavanja, MC, Residential Radon Exposure and Lung Cancer Among Nonsmoking
Women, J Nat Cancer Inst, Vol 86, No. 24, 12/21/94
There have been several other studies involving never smokers that were
negative. A curious observation is that the Iowa has one of the the highest
average radon concentrations in the US, but one of the lowest incidences of
lung cancer, according the SEER Report. It seems Iowa would be a great
place to study lung cancer etiology in never smokers, of which radon could
be one of the many factors studied. You've mentioned in previous posts that
this study is forthcoming.
Now, what if the EPA is correct and about 18,000 lung cancers per year are
attributable to radon. BEIR VI states that if every home is reduced to
below the EPA action level then only about 1/3 of lung (about 6000) cancers
will go away. Why? Because most of the lung cancer numbers are derived from
smoking and very small risk values applied to the large number of people in
the lowest categories.
In most case-control studies, most of the lung cancers (about 50%-70%)
occur in people who are exposed to < 2 pCi/L; and about 70%-90% of the lung
cancer occur in people with less than 4 pCi/L. Odds ratios cited by authors
on radon levels above 4 pCi/L are based on very small numbers, sometimes as
few as 2 or 3 excess cancers.
Personally, I think there are very good reasons to be skeptical.
Tom
epirad@mchsi.com wrote:
>
> Maury,
>
> You stated,
>
> " When thinking about the increasing weight of
> evidence favoring beneficial health effects from
> exposure to low level radiation (such as household
> radon), I cannot bring myself to get very concerned about
> the EPA radon campaign."
>
> Maury, other than Dr. Cohen's data, which he himself
> says does not suggest hormesis (to do so he says would
> make his findings subject to the ecologic fallacy), can
> you point me to any well designed study that
> demonstrates residential radon exposure decreases lung
> cancer risk?
>
> Please see this reference for my view of this issue:
> http://www.ntp.org.uk/951-TUD.pdf
>
> Bill Field
> >
> >
> > Bill, thanks for taking the trouble to refer me to relevant data. My
> > impressions, however, are that you folks are suggesting with an
> > epidemiological risk factor of 0.5, that out of an annual total lung
> > cancer
> > incidence of 157,400 cases, 18,600 or about 12% are attributable to
> > radon. I
> > don't believe those radon cases could hope to be distinguished from the
> > noise
> > or error variance. When thinking about the increasing weight of
> > evidence
> > favoring beneficial health effects from exposure to low level radiation
> > (such
> > as household radon), I cannot bring myself to get very concerned about
> > the EPA
> > radon campaign -- except for some of my darker suspicions which already
> > have
> > been well-fed over the years by the performance of EPA. I just cannot
> > view
> > radon as a threat and I suspect it might even be beneficial to us.
> > Perhaps my
> > ignorance, but time will tell after I'm long gone.
> >
> > Thanks again for your response to me.
> > Sincerely,
> > Maury maury@webtexas.com
> > ================================
> > epirad@mchsi.com wrote:
> >
> > > Maury,
> > >
> > > Our direct observations
> > > http://www.cheec.uiowa.edu/misc/radon.html are in
> > > agreement with the BEIR VI
> > > (http://www.epa.gov/iaq/radon/beirvi1.html)projections
> > > which estimate that approximately 18,600 lung cancer
> > > deaths each year in the United States are associated
> > > with prolonged radon progeny exposure.
> > >
> > > Bill Field
> > > > Bill,
> > > >
> > > > Would you select an objective, reliable measure of the impact of
> > > > cancer on human health, e.g., mortality, morbidity, longevity, etc. and
> > > > tell me what that observation is today in perhaps the US, or the world,
> > > > or Iowa, or whatever? Then, if we could suddenly cause all radon and its
> > > >
> > > > progeny to disappear completely from the earth while all other
> > > > conditions remain unchanged, what do you see in any hard data, or
> > > > believe would be the observed effect or change in that selected cancer
> > > > measurement in, say, 20 years or so?
> > > > Cheers,
> > > > Maury Siskel maury@webtexas.com
> >
> > ------------------
> > It is the soldier, not the campus organizer, who has given us the
> > freedom to demonstrate. Charles M. Province
> > ************************************************************************
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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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