AW: AW: [ RadSafe ] Ranger site, uranium in Australia & cancer clusters among aborigines

[John Jacobus]

Dr. Rainer,
Thank you for your comments. I was commenting more on
the statistical aspects of there studies and not the
underlying cause for the increase in leukemia.

--- Rainer.Facius at dlr.de wrote:

> John,
> 
>  
> 
> in the case of childhood leukaemia (which I referred
> to), the clustering is interpreted as the hallmark
> of an 'epidemic', specifically the "rare response to
> a rather common infectious agent". Intensive
> "population mixing" might then trigger such
> clustered outbreaks. Since for about a dozen or so
> cancers the contribution of infectious agents has
> been demonstrated, this might apply to those too.
> 
>  
> 
> Kind regards, Rainer
> 
>  
> 
>  
> 
> Kinlen L J.
> Infection, childhood leukaemia and the Seascale
> cluster.
> Radiol Prot Bull 226#October(2000)9-18
> 
> Abstract
> 
> 
> 
> A significant excess of childhood leukaemias has
> been observed in the village of Seascale near the
> Sellafield nuclear fuel reprocesing plant operated
> by British Nuclear Fuels plc. There is evidence to
> indicate that this and other recent excesses could
> be due to infection. This paper, which formed the
> basis of Professor Kinlen's recent Chilton Seminar,
> reviews the evidence on infection in childhood
> leukaemia both in relation to the Seascale cluster
> and more generally.
> 
>  
> 
>  
> 
> McNally R J Q, Eden T O B.
> An infectious aetiology for childhood leukaemia: a
> review of the evidence.
> Br J Haematology 127#3(2004)243-63.
> 
> Abstract
> 
> There are three current hypotheses concerning
> infectious mechanisms in the aetiology of childhood
> leukaemia: exposure in utero or around the time of
> birth, delayed exposure beyond the first year of
> life to common infections and unusual population
> mixing. No specific virus has been definitively
> linked with childhood leukaemia and there is no
> evidence to date of viral genomic inclusions within
> leukaemic cells. The case-control and cohort studies
> have revealed equivocal results. Maternal infection
> during pregnancy has been linked with increased risk
> whilst breast feeding and day care attendance in the
> first year of life appear to be protective. There is
> inconclusive evidence from studies on early
> childhood infectious exposures, vaccination and
> social mixing. Some supportive evidence for an
> infectious aetiology is provided by the findings of
> space-time clustering and seasonal variation.
> Spatial clustering suggests that higher incidence is
> confined to specific areas with increased levels of
> population mixing, particularly in previously
> isolated populations. Ecological studies have also
> shown excess incidence with higher population
> mixing. The marked childhood peak in resource-rich
> countries and an increased incidence of the
> childhood peak in acute lymphoblastic leukaemia
> (ALL) (occurring at ages 2-6 years predominantly
> with precursor B-cell ALL) is supportive of the
> concept that reduced early infection may play a
> role. Genetically determined individual response to
> infection may be critical in the proliferation of
> preleukaemic clones as evidenced by the human
> leucocyte antigen class II polymorphic variant
> association with precursor B-cell and T-cell ALL.
> 
> 
> 
> ________________________________
> 
> Von: John Jacobus [mailto:crispy_bird at yahoo.com]
> Gesendet: Sa 01.12.2007 20:54
> An: Facius, Rainer; bcradsafers at hotmail.com;
> radsafe at radlab.nl
> Betreff: Re: AW: [ RadSafe ] Ranger site, uranium in
> Australia & cancer clusters among aborigines
> 
> 
> Is the clusing caused by the population, or to the
> studies being done around location, i.e., the
> nuclear
> power plant?  Populations studies are usually based
> on
> incidence per population size, so the bias between
> small populations and large is reduced.
> 
> Of course, you can have populations so small that
> certain types of cancers do not appear.  Certain
> types
> of brain cancers are so rare, that one or two may
> occur over a decade.  Thus, when you have three in
> three years, it becomes an "epidemic."
> 
> --- Rainer.Facius at dlr.de wrote:
> 
> > For leukemia clusters - especially in childhood -
> in
> > populations around nuclear power reactors the
> > contribution of 'migration' of workers with their
> > families to such usually new settlements appears
> to
> > be an established 'cause'.
> >
> > Rainer Facius
> 
> 
> 


+++++++++++++++++++
"Courage is what it takes to stand up and speak, Courage is also what it takes to sit down and listen." -- Sir Winston Churchill

-- John
John Jacobus, MS
Certified Health Physicist
e-mail:  crispy_bird at yahoo.com


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