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RE: Objectivity
-----Original Message-----
From: Les Crable
Jim Muckerheide,
If your postings are to be perceived with at least a hint of
objectivity,
try posting abstracts on both sides of the issue such as these.
<?? We have found no credible studies on the other side of the issue.
Nor have the critics that have used "science innuendo" to challenge
substantial results confirmed in hundreds of analyses.>
I see Tomasek's study did not match cases to controls by smoking status
either.
<Irrelevant. Smoking is a noise level factor in the rsults. It _could_
affect a study. Not enough to change the result. Much less likely to
affect results in two studies, either in the same population, or
separate populations. And a chance of affecting all of many hundreds of
studies is ten to the minus MANY zeros.>
<It's funny that this smoking rhetoric about a minor factor is trumpeted
while the lack of doses to cases destroys the statistical basis for
these small statistical groups that therefore simply vary wildly, and
nothing is said to question this fatal flaw.>
<These arguments are simply dissembling by the LNT-committed (this is
NOT committed to the science, just to the bureaucracies and industries
that gain and provide the funds, as acknowledged in science meetings by
these people). It's just rhetoric without science, and repeated by the
those who don't apply the rhetoric into analysis.>
Regards, Jim Muckerheide
=====================
It looks like they dependent on multivariate analysis like Field.
Radiat Environ Biophys 2001 Sep;40(3):207-11
Microdosimetric calculation oCent Eur J Public Health 2001
Aug;9(3):150-3
Study of lung cancer and residential radon in the Czech Republic.
Tomasek L, Muller T, Kunz E, Heribanova A, Matzner J, Placek V, Burian
I,
Holecek J.
National Radiation Protection Institute, Srobarova 48, 100 00 Prague,
Czech
Republic. ltomasek@suro.cz
Epidemiological evidence of lung cancer risk from radon is based mainly
on
studies of men employed underground in mines where exposures are
relatively
high in comparison to indoor exposure. Risk from residential radon can
be
estimated from occupational studies. Nevertheless, as such
extrapolations
depend on a number of assumptions, direct estimation of the risk is
needed.
The present study of lung cancer mortality was designed as a follow-up
of a
population (N = 12,004) in a radon prone area of the Czech Republic
covering
the period 1960-1999. Information on vital status and causes of death
were
obtained mostly from local authorities and from the national population
registry. Exposure estimates were based on one year measurements of
radon
progeny in most houses of the study area (74%). Exposures outside the
area
(16%) were based on country radon mapping. Mean concentration of 509
Bq/m3
is higher than the country estimate by a factor of 5. By 1999, a total
of
210 lung cancers were observed, somewhat more than the nationally
expected
number (O/E = 1.10) in comparison to generally low numbers corresponding
to
cancers other than lung (O/E = 0.81). The excess relative risk per
standard
radon concentration (100 Bq/m3) was 0.087 (90% CI: 0.017-0.208). This
value
is consistent with risk coefficients derived in other indoor studies.
The
present follow-up demonstrated that increased incidence of lung cancer
depends linearly on exposure in terms of average radon concentration in
the
course of previous 5-34 years. Adjustment for smoking did not
substantially
change this estimate, although the risk coefficient for non-smokers
(0.130)
was higher in comparison to that for ever smokers (0.069), but not
statistically different.f absorption fraction and the resulting dose
conversion factor for radon progeny.
-----------------
Nikezic D, Yu KN.
University of Kragujevac, Faculty of Science, Yugoslavia.
It is an established fact that radon progeny can induce lung cancers.
However, there is a well-known discrepancy between the epidemiologically
derived dose conversion factor for radon progeny (4 mSv/WLM) and the
dosimetrically derived value (15 mSv/WLM) (mSv is a unit of the dose
while
WLM is a unit of exposure to radon progeny). Up to now there is no
satisfactory explanation to this. In the present study we propose that
microdosimetry will help reduce the discrepancy significantly. The ICRP
Human Respiratory Tract Model (HRTM) has been applied to calculate the
effective dose conversion factor. All parameters have been kept at their
best estimates. Modifications were made in the calculation of the
absorbed
fractions of alpha particles. In contrast to the ICRP approach where the
energy has been considered to be deposited in the layer containing the
sensitive cells, we used a microdosimetric approach in which the alpha
particles deposit their energy only in the nuclei of sensitive cells.
This
modification alone has lowered the dose conversion factor by about
one-third
(from 15 mSv/WLM down to approximately 10 mSv/WLM).
Les Crable
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