SESSION IV DISCUSSION
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talking about? If these values are used later on for estimation of radiation risks, we must keep in mind that in all these estimations, in one
way or another, a linear relation between dose and probability of effect
is assumed. If this is so, we are almost bound to use average values
and not extreme ones. If we go to high doses, of course, this breaks
down; but, at the low doses we are talking about, I think that it is only
meaningful to uSe mean concentrations for the evaluation of risks.