Lab researchers uncover new effects of radon -Reply

[Mark Hanlon <MarkH@nch.edu.au>]

Dear Jim, and fellow Radsafers,

Hydrogen peroxide and superoxide anions are also part of the normal
host defense response : they are produced (in particular) during the
oxidative burst response of neutrophils, which occurs after normal
neutrophils phagocytose (ingest) "foreign" particles, including bacteria.

Neutrophils have mechanisms which limit the potential for damage by
peroxides and superoxides, including myeloperoxidase and superoxide
dismutase (enzymes), which break down these "reactive oxygen
intermediaries". 

Presumably, "normal" people are encountering, and in fact using, these
radicals all the time, over their whole life span.  

There is an hereditary condition, known as Chronic Granulomatous
Disease, in which individuals lack the capacity to initiate the neutrophil
respiratory burst  -  would it follw that these people will have a lower
cancer rate ?  ( I doubt that enough data have been collected for
statistical analysis, but I'd be very interested if anyone has looked at
this). 


Mark Hanlon,
Radiation Safety Officer,
The New Children's Hospital,
P.O. Box 3515,
PARRAMATTA, NSW, 2124.
Australia.


Phone   61 2 9845 3324              FAX   61 2 9845 0831  


email    markh@nch.edu.au