FW: Nashville Tennessean; Mortality vs. Morbidity Studies

["James G. Barnes" <mail15077@pop.net>]

Dear all,

"The reports of illness around various nuclear installations may be more 
illusion than reality.   These reports contrast sharply to the careful 
mortality studies that have been done which show that nuclear workers are 
healthier than the general population and live longer."  (from a posting 
from Robert Holloway)


Mr. Holloway's discussion raises an interesting issue, I think.  I don't 
want to start a firestorm on this, but I wonder if we might be missing how 
the Tennessean is framing the debate.  First, I don't believe that bulk of 
the information presented in the Tennessean is anything other than 
pseudo-epidemiology.  The premise of the article is that persons living in 
the vicinity of nuclear facilities are displaying certain non-fatal 
physical symptoms.  This is probably "journalistic case selection" at work 
as regards the U.S., because I didn't see any interviews with people who 
were "feeling just fine, thank you very much."

But the discussion of these symptoms being seen in Russian territories, 
because of the relatively higher doses to the population from Chernobyl and 
other nuclear disasters, is probably not so trivial.  Some Russian 
researchers do consider that some of these effects may be linked in some 
way to radiation, although stress, chemical contamination, and other 
socio-psychological effects may also be likely causes of the observed 
symptoms.

To my knowledge, most of the studies of radiation effects are based upon 
mortality.  From these studies it has been established that radiation might 
cause cancer in a certain population of people, and that there is some dose 
response relationship between the radiation dose and cancer induction. 
 There does not appear to be an equally vast body of data for morbidity 
studying non-fatal, non-carcinogenic effects.

So without the morbidity data, how does one use mortality data to reject a 
hypothesis that folks exposed to moderate doses (say, for sake of 
discussion, 10 - 50 Rem TEDE) of radiation may be getting sick (but not 
dying) from that exposure.  Just because the doses don't cause fatal 
cancer, does that necessarily prove that there is not some other non-fatal 
effect?  I would think that only after performing a body of morbidity 
studies (fully acknowledging that they are expensive, hard to control, etc. 
etc.), that any kind of scientific statement regarding these types of 
effects could be made.

I'd be interested in others' thoughts about this.

Jim Barnes, CHP
Radiation Safety Officer
Rocketdyne / Boeing

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