Re: Ecologic LNT study - reply from Dr. Lubin

[Jim Muckerheide <jmuckerheide@delphi.com>]

Jim Muckerheide wrote:

> However, in addition to other studies identified by Cohen in 1987, see other
> studies at:
> http://cnts.wpi.edu/RSH/Data_Docs/1-2/6/3/1263list.html
> http://cnts.wpi.edu/RSH/Data_Docs/1-2/6/3/Rev%202%201263list.html
> http://cnts.wpi.edu/RSH/Data_Docs/1-2/6/3/1/12631list.html
> http://cnts.wpi.edu/RSH/Data_Docs/1-2/6/3/1/Rev%202%2012631list.html

Also consider the following totally independent study by Ken Bogen.

He used EPA-supported _environmental_ radon data (not home measurements) vs.
lung cancer by county in women 1950-54 (low smoking) that produces the SAME
dose-response as Cohen. (Must be just another confounding effect or competing
risk! :-)

"MATERIALS AND METHODS

"Residential Mortality and Related Smoking Data. 

"Age- and county-specific 1950-54 Lung Cancer Mortality (LCM) rates were
obtained for U.S. white females (WF) in 5-y age intervals ending in 85+ y,
excluding data for Virginia due to unreliability of VA-county-level data at
that time (Marsh et al., 1996). Analyses excluded data on women <40 y, for
whom LCM was quite rare. Only ~11% (vs. ~5%) of WF who died at 40+ (vs. 60+) y
in 1950-54 ever smoked, based on survey data covering this period (Mills and
Porter, 1953; Haenzsel and Shimkin, 1956). 

"Based on the latter studies' account of how those smokers tended to smoke
less and start at a later age relative to subsequent smoking women, it can be
estimated that LCM in all WF who died at 40+ (vs. 60+) y in 1950-54 was
increased by an RR of 1.74 (vs. 1.16) over the baseline rate(s) expected for
WF never-smokers who died during that period. This ~5-fold difference in
expected excess RR for 1950-54 LCM in WF of age 40+ vs. 60+ y indicates that
any ecologic association between radon exposure and LCM in these women due
solely or primarily to confounding by smoking should be reduced in WF aged 60+
vs. 40+ y. 

"Rn-related trends for 1950-54 LCM adjusted for age and other factors were
therefore examined for WF of age 40+ and 60+ y as described below. 

"WF data were modeled for age <80 y only, because the general pattern of LCM
increase (a very nearly cubic function of age) did not hold for the 80-84 and
85+ age groups. The mortality-rate decline in the oldest age groups well known
to pertain to nearly all types of cancer (Armitage and Doll, 1957) may be due,
e.g., to data unreliability (Doll and Peto, 1981) and/or population
heterogeneity in cancer susceptibility, neither of which are addressed by the
CD2 model. 

"For modeling, county-level LCM data adjusted by family income (see below)
were pooled within 6 ranges of mean household radon exposure. 

"Rn-Exposure, Socioeconomic and Climatic Data for U.S. Counties. 

"This study used new estimates of annual geometric mean household radon
concentrations in U.S. counties based on analyses of long-term vs. short-term
U.S. EPA monitoring data adjusted for climatic and other variates (Price,
1997; Price et al., 1998). Geometric mean levels were scaled uniformly to
corresponding arithmetic means assuming lognormal intra-county distributions
with a common geometric standard deviation of 2.0 (Cohen, 1992a; Price, 1997). 

"In addition to VA data as noted, data for major retirement states (AZ, CA,
FL) were dropped in view of survey data indicating the high % of lifetime
spent near residence at time of death in non-retirement states (Cohen, 1992b)
expected even more so for WF dying in 1950-54. 

"For the remaining 2,821 counties, 12 types of 1950 demographic/socioeconomic
data (USBC, 1953) and 5 typical 1953-1975 climatic measures (Apte et al.,
1997) were binned into county quintiles, and were, together with a 3-level
dietary Se index (Clark et al., 1991) and U.S. region (among 9), included
separately and in pairs as factors used together with age in adjusted trend
analyses."

See the Cohen-equivalent dose-response relationship in Fig 2(a) in:
http://www.belleonline.com/n3v72.html

(I'd send the fig, but we know radsafe and html or doc files! :-)

See the fig also as Fig. 1 in Bogen's response to comments that shows tests
vs. with "the cytotoxic potency of D0 = 35cGy assumed was the average of
published values for alpha-induced killing of human lung cells in vitro."
http://www.belleonline.com/n11v72.html

By the way, last year Bogen said that he had no more funding for this work.
Want to ask Lubin about his funding? Note Bogen's note on the occupational
data that Lubin would not give him the individual data. The same is true with
RERF. They're not in or consistent with the DOE CEDR files. They only give
"processed" data sets, even to the BEIR Committee analysts! Does anybody
wonder why? 

Regards, Jim
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