Re: Radiation - net benefit or detriment?

[Bernard L Cohen <blc+@pitt.edu>]

On Sun, 11 Feb 2001, Bjorn Cedervall wrote:
> 
> All the quantitative work I have seen with radiation induced DNA 
> double-strand breaks (DSBs) point at a linear induction with increasing 
> radiation dose 

	--The fact that the number of DSBs induced by radiation is linear
with dose seems obvious. However, it is estimated that chemical and
thermal effects induce about 200 DSBs per cell per year, whereas 10 rem of
radiation per year induces only about 4 per cell per year, so the
contribution of low level radiation to the body's DSB accumulation is
relatively negligible. This suggests that we consider the positive effects
of low level radiation - stimulation of immune system, stimulated
production of repair enzymes, etc - as relevant factors in deciding
whether the net effect is good or bad.

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