[ RadSafe ] Increase in cancer in Sweden can be traced toChernobyl

Brennan, Mike (DOH) Mike.Brennan at DOH.WA.GOV
Mon Jun 4 16:15:21 CDT 2007


I completely defer to Franz's first-hand knowledge of the living conditions of the Sami; I was going with the best references I had.  I believe we are not in disagreement about the most salient point; that the level of medical attention and record keeping for the rural, isolated population of the area in question before Chernobyl was likely not to the standards of that after Chernobyl, and that this change could produced an apparent increase in cancer rates regardless of whether or not such an increase actually occurred.

I realize that it is much cheaper to do research by taking other people's studies and hammering the data until is bent into a new shape, but I am unenthusiastic about the findings if no new information is added to the mix.  On those occasions that I've done some original research I learned a great deal by going out myself to collect the samples.  Insight gained from actually seeing and experiencing the conditions saved me from falling into some traps, and has allowed me to help some others whose work I've review avoid embarrassing errors.

I am less than in love with "population dose" in general, and even more so when the source of the exposure is highly non-homogeneous, as plume deposition usually is.  Populations don't get cancer from radiation: individuals do.  And individuals get cancer from the dose they personally receive, not because of the average of the dose of a population some researcher chooses to assign them to.  Sometimes simplified models are useful, and sometimes they are all that you have, but they are not reality.

The real world is a multi-dimensional, highly dynamic place.  Simple models can produce useful insights, if you keep in mind the limitations of your model.  If you don't keep the limitations in mind the most likely thing that a simple model will produce is confidence in a conclusion that is wrong, or at least not supported.
  
-----Original Message-----
From: Franz Schönhofer [mailto:franz.schoenhofer at chello.at] 
Sent: Sunday, June 03, 2007 1:10 PM
To: Brennan, Mike (DOH); radsafe at radlab.nl; brickner at smile.com; jim_hoerner at hotmail.com
Subject: AW: [ RadSafe ] Increase in cancer in Sweden can be traced toChernobyl

Mike,

The physorg website mentioned a research done in 2004 and that Tondel will soon defend his thesis. I received an electronic copy of the thesis yesterday, so if you are really interested I can sent it to you and other RADSAFErs interested. I believe that it does not make much sense to speculate what the author might have done or intended, but one should read his publications. The thesis has a very large number of references including the authors papers. I myself have not found time to read the thesis carefully, not to speak about my poor knowledge of epidemiology which prohibits me from judging his findings. Nevertheless I noted even in my hurry some weak points, which might not be so evident for persons less acquainted with the Chernobyl accident, its consequences in Europe and the "non-radioactive" Sweden, including cultural points like reindeer herding. 

The contamination in Sweden was - as all over Europe - extremely inhomogeneous. In the electronic form of the thesis I received I notice that there are no tables, no graphs and no maps. I think that this would be essential in order to describe the geographical distribution of the contamination and to give the reader an impression about the contamination.
I have spent in the late sixties of last century many summers in Sweden, working in cellulose and paper factories, mostly in the north of Sweden and hence I speak fluently Swedish, so I am familiar with the areas and the counties named in the thesis like Swedish readers will be - but hardly anybody outside Sweden. Moreover I have been during and long after the Chernobyl accident in contact with the Swedish Radiation Protection Institute (Svenska Stralskyddsinstitutet, SSI). The most heavily contaminated areas in Sweden were (please consult a map!) the areas of Gaevle (slightly north of Stockholm), the area of Sundsvall (several hundred kilometers north of Stockholm at the coast, location of a cellulose factory I have been working at decades ago) and Oestersund almost exactly in the middle of Sweden. Those areas are  n o t  in the far north of Sweden as written in the thesis!!!!

The northern areas of Sweden (and Finland and Norway) have been heavily affected by the atmospheric nuclear bomb tests of the late fifties and very early sixties of last century, so residual Cs-137 contamination from these nuclear bomb tests is still large. I do not know, whether this has been considered by Tondel. As well I have not been able to verify, whether he distinguishes correctly between external irradiation and internal one. 

I respectfully disagree with your comments on the "nomadic reindeer herders"
of the "far North". What you call a "wrong-headed panic move" of the Swedish government has to be seen in the context of the European Union, public opinion and the various green, antinuclear movements. Such decisions were not made on scientific grounds and will not be done in the future! 

I agree that the Chernobyl accident had a disastrous impact on the reindeer herders - the Sami-population, but please do not claim, that they have been forced to convert an "independent active live to living in settlements".
They have done this already decades ago, temporarily accompaning their reindeer herds. 

Best regards, vaenlig haelsning

Franz  


Franz Schoenhofer, PhD
MinRat i.R.
Habicherg. 31/7
A-1160 Wien/Vienna
AUSTRIA



It would be interesting to see how the study was conducted and what the raw data looked like.  Off hand I can remember other "studies" that found "statistically significant" increases do to whatever the researcher chose to believe was the cause.

In connection with Chernobyl and its effect in the far North there is a factor that would be difficult, perhaps impossible to account for.  In response to Chernobyl a lot more attention was focused on a population that was primarily rural, and some 10% nomadic reindeer herders.  Then Swedish government, in one of those wrong-headed panic moves so typical of responses to radiation issues, confiscated and slaughtered most of the reindeer, because they were eating fallout contaminated vegetation.  The nomads went from living independent active lives to living in settlements, subsisting on the dole.  Between the increased ability of satiations to count illnesses and the effect of lifestyle change (diet and physical activity) and stress it would be difficult say what a true background rate of illnesses, including cancer, would be.  And without a background rate it is hard to know if one is seeing an actual increase.

I am not saying that there has been no cancer increase in connection with Chernobyl.  I am saying that the more confident a researcher is that he has found "a small but statistically significant increase" in cancer rates and that he know just where it came from, the less confident I am that the researcher is actually letting the data speak for itself.

-----Original Message-----
From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf Of Jim Hoerner
Sent: Thursday, May 31, 2007 5:54 PM
To: Know_Nukes at yahoogroups.com
Cc: radsafe at radlab.nl
Subject: [ RadSafe ] Increase in cancer in Sweden can be traced to Chernobyl

Increase in cancer in Sweden can be traced to Chernobyl

The incidence of cancer in northern Sweden increased following the accident at the nuclear power plant in Chernobyl in 1986. This was the finding of a much-debated study from Linköping University in Sweden from 2004.

Was the increase in cancer caused by the radioactive fallout from Chernobyl or could it be explained by other circumstances? New research from Linköping University provides scientific support for the Chernobyl connection.

"This issue is important because the indicated increased risk may come to influence the prevailing exposure limits for the population. Enhanced knowledge of the risks entailed by radioactive radiation is key to work for radiation safety and makes it possible to prevent diseases," says Martin Tondel, a physician and researcher in environmental medicine who will soon be defending his doctoral dissertation Malignancies in Sweden after the Chernobyl Accident in 1986.

In two studies using different methods, Martin Tondel has shown a small but statistically significant increase in the incidence of cancer in northern Sweden, where the fallout of radioactive cesium 137 was at its most intense.

The cancer risk increased with rising fallout intensity: up to a 20-percent increase in the highest of six categories. This means that 3.8 percent of the cancer cases up to 1999 can be ascribed to the fallout. This increased risk, in turn, is 26 times higher than the latest risk estimate for the survivors of the atom bombs in Hiroshima and Nagasaki, whose exposure was many times higher.

[This is not credible, IMO.  Someone needs to scrutinize this work, please. 
- JH]

The increase in Tondel's studies came a remarkably short time after the disaster, since it is usually assumed that it takes decades for cancer to develop. The dissertation discusses the interpretation of the research findings from the perspective of the theory of science.

The conclusion is that there is scientific support for a connection between the radioactive fallout and the increase in the number of cancer cases.  
[That IS credible. - JH]

Source: Linköping University

http://www.physorg.com/printnews.php?newsid=99758918







More information about the RadSafe mailing list