[ RadSafe ] dose RATE of ANY Medicine is the decisive variable

[goldinem at songs.sce.com]

In this discussion (?) of dose versus dose rate, I always considered the
1990 paper by Daniel Billen to be a forerunner.  He compared ("Commentary -
Spontaneous DNA Damage and Its Significance for the 'Negligible Dose'
Controversy in Radiation Protection"  Radiat. Res. 124, 242-245) the rate
of DNA damage due to spontaneous events (metabolism) to those from ionizing
radiation.  His table, with a little interpretation clearly showed that
when you compare rates, spontaneous damage greatly exceeded damage rates
from radiation as long as the radiation was "chronic."  I know that many of
you folks out there will say that measurement of molecular damage doesn't
account for enhanced immunological expression or some other larger-scale
effects (tissue, organ, whatever) but it doesn't take much to point out
that, at least for low LET radiation, you can postulate that repair
mechanisms capable of fixing metabolic damage would obviously be able to
fix damage from chronic radiation but might be overwhelmed by acute doses
(i.e. atomic bomb survivors).

I've spoken with some folks who say this approach is perhaps too simplistic
but it sure holds more water than much of the epidemiology out there.
IMHO.

Eric M. Goldin, CHP
<goldinem at songs.sce.com>