Re[2]: how many sensitive cells?

[tdc@ehssun.lbl.gov]

>Not correct. "D" in any form is energy _concentration_ (energy per unit mass).
>E & E just play around with it. It doesn't provide energy absorbed (energy
>per unit mass times mass of the biological unit of interest - cell,
>organism, or population).

Jim,

I think you mis understand my point - or I mis made it.

I agree Rad dose units are concentration (energy per unit mass) and it is
ASSUMED to be uniform whole body - THUS under such assumption the
concentration need not be multiplied by the total mass for total energy
deposited.  I don't believe I suggested it did to begin with.

BUT my comment was meant to address the issue in the other direction.

I believe the original question asked why BOTH to total mass and total
energy weren't considered.  I suggest that when the exposure is NOT
uniform either through attenuation or localization and then the
EDE calculations are done, they effectively average the dose
(concentration) over the whole body mass.  This is how one gets micro R of
dose from 100's of mR of exposure in dental x-ray for instance.

THIS process mathmatically DOES consider the total energy and total mass
and when used by LNT believers is equated to risk.  Same for population
dose.

Since the basic dose unit is a concentration unit and the risk estimates
are based on this concentration unit - calculation of total energy is
meaningless.

Ted de Castro
tdc@ehssun.lbl.gov
University of California Lawrence Berkeley Laboratory
Bldg 90 Rm 0026B
Berkeley, CA 94720
(510) 486-5256
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