The nominal annual risk level for fatal
cancer associated with the 100 mrem/yr
dose standard is 5.75 × 10¥5. This is
comparable to the range of risks
represented by national and
international regulations identified by
NAS for EPA to consider, and is
premised on a dose level the NAS has
addressed favorably as a matter of
international regulatory consensus (NAS
Report pp. 40–41, Tables 2–3 and 2–4).
Considering that this standard will
apply for up to 1 million years, we
believe this represents a level of risk
that will protect public health and
safety in the far future. However, for the
reasons described above, we do not
believe it is appropriate to view the
standard through a strict risk
perspective, and caution against doing
so. Further, even if the risk correlations
could be assumed valid over such times,
the nominal risk represented by
projected doses may be a reflection of
the uncertainties inherent in such
projections, and therefore overstated.
ICRP states, for example, that ‘‘as the
time frame increases, some allowance
should be made for assessed dose or risk
exceeding the dose or risk constraint