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RE: Apparent anti-correlations between geographic radiation and cance r are not surprising



Dan,  



Had I expected such an avalanche of messages, I would have abstained...



I agree that no clear conclusion can be drawn from comparing the maps.

What I do not understand is why the "negative image" effect appears to

be so consistent over the all USA territory.  If radiation has a very

small influence on cancer incidence, I would have expected randomly

distributed excesses and deficits, without relation, positive or

negative, to radiation levels, that is, neither correlation or

anti-correlation.  



Is it conceivable that important health factors known to influence the

risk of cancer (such as education, socio-economic status, medical

coverage, ... ) be consistently correlated with geography, geology and

elevation?



I may be wrong and I welcome explanations.



Sincerely, happy new year.    



Philippe Duport





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

From: owner-radsafe@list.vanderbilt.edu

[mailto:owner-radsafe@list.vanderbilt.edu] On Behalf Of Strom, Daniel J

Sent: January 1, 2003 2:52 PM

To: RADSAFE Listserver (E-mail)

Cc: Strom, Daniel J

Subject: Apparent anti-correlations between geographic radiation and

cance r are not surprising



Philippe DuPort reads way more into cancer and radiation maps than is

warranted. The apparent geographical anti-correlation of radon and gamma

dose rate with lung cancer and all cancers isn't surprising, given that

neither radon nor other background radiation are predominant causes of

lung

cancer or all cancers.



To understand why, let's start with a look at the statistics (as of

about 2

or 3 years ago):



1) There were 552,200 US cancer deaths in 1999

2) There were 2,339,000 US deaths in the period 4/98-3/99



The ratio of these two numbers shows that 23.6% of all deaths in USA

were

due to cancer in 1999.



3) The population of USA was 274,625,507 as of 20:09 EDT Apr 17, 2000.



>From this one can calculate rates:



0.00852 y?1 	death rate; one in 117 people die each year

0.00201 y?1 	cancer death rate; one in 497 people die of cancer each

year



What proportion of the cancer deaths are attributable to background

radiation and radon decay products? If one assumes 



1)  5% per Sv excess fatal cancer rate and a linear nonthreshold dose

response model (EPA's numbers);

2)  0.002 Sv y-1 from background (NCRP's 1987 Report 93 number of

roughly

0.003 Sv/y (300 mrem/y) is too high because the w_lung was used as 0.08,

not

0.12, and preliminary radon data were used); and

3)  75-year life expectancy,



then one calculates a lifetime fatal cancer risk of 0.75% due to

background

radiation including radon decay products in indoor air. Gamma dose rates

from primordial radionuclides make up a small portion of this, so they

would

be expected to contribute very little to explaining variations in cancer

rates.



So, 23.6% of people die of cancer, and radiation under EPA's LNT model

would

account for 0.75% of deaths. Taking the ratio of these two numbers, we

would

expect that variations in radon and other radiation would explain

0.75/23.6

= 0.032 of the variance in all-cancer rates, that is, radiation would be

causative in 3.2% of cancer deaths. This means that there should be a

correlation coefficient (r-square) of 0.032 between background radiation

and

all cancers. The r-square for radon and lung cancer should be higher,

probably around 0.10 or so. It is not surprising that such a small

portion

of the variability in cancer rates due to radiation and radon decay

products

might be masked by other larger risk factors. Strong cancer causative

factors including diet, genetic predisposition, smoking, and lifestyle

factors are also strongly correlated with geography.



However, all geographic effects, radiation or otherwise, are partly

reduced

by migration and immigration.



Because of these factors, epidemiologists don't take so-called

ecological

correlations (e.g., Cohen's county lung cancer rates associated with

county

radon measurements) very seriously, but rather rely on case-control and

cohort study designs.



- Dan Strom



The opinions expressed above, if any, are mine alone and have not been

reviewed or approved by Battelle, the Pacific Northwest National

Laboratory,

or the U.S. Department of Energy.



Daniel J. Strom, Ph.D., CHP

Environmental Technology Division, Pacific Northwest National Laboratory

Mail Stop K3-56, PO BOX 999, Richland, Washington 99352-0999 USA

Overnight: Battelle for the U.S. DOE, 790 6th St., Richland WA 99352

ATTN:

Dan Strom K3-56

Telephone (509) 375-2626 FAX (509) 375-2019 mailto:strom@pnl.gov

Brief Resume: http://www.pnl.gov/bayesian/strom/strombio.htm

Pagemaster for  http://www.pnl.gov/bayesian   http://qecc.pnl.gov

http://bidug.pnl.gov



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

From: Philippe Duport [mailto:pduport@uottawa.ca]

Sent: Tuesday, December 31, 2002 12:00 PM

To: Jacobus, John (NIH/OD/ORS); 'Jerry Cohen'; 'Ted Rockwell';

BLHamrick@AOL.COM; 'John Cameron'; radsafe@list.vanderbilt.edu

Subject: RE: Not using LNT to calculate risk does not mean there is no

risk.





John,

 

Are low doses harmful?  The USA all cancers and lung cancer maps are the

negative images of both the gamma radiation and radon maps.  Is such a

consistent contrast due to chance alone?  One can accept statistical

fluctuations in some states, but in all states?  Statisticians, please

tell

us what is the probability for this to be due to chance alone in

virtually

all US states.  

 

John, would agree to live in Denver, with annual doses more than half

the

annual dose limit for radiation workers?  Any nuclear facility with such

dose rates lasting for a whole life would be evacuated, don't you think?

Should Denver and all similar places in world be evacuated?

 

Cancer map:

http://www.dceg.cancer.gov/cgi-bin/atlas/mapview2?direct=acccwm70

<http://www.dceg.cancer.gov/cgi-bin/atlas/mapview2?direct=acccwm70> 

 

Lung cancer map:

http://www.dceg.cancer.gov/atlas/download/pdf2/lun-maps.pdf

<http://www.dceg.cancer.gov/atlas/download/pdf2/lun-maps.pdf> 

 

Gamma radiation map:

http:  <http://www.epa.gov/iaq/radon/zonemap.html>

//www.epa.gov/iaq/radon/zonemap.html ;

http://energy.cr.usgs.gov/radon/DDS-9.html

<http://energy.cr.usgs.gov/radon/DDS-9.html> 

 

Radon map:

http://www.epa.gov/iaq/radon/zonemap.html

<http://www.epa.gov/iaq/radon/zonemap.html> 

 

Happy new year to all,

. . .





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