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• accounting for a number of safety indicators which are not concerned with the individual
but rather with society as a whole.
The assessment of the “risk proper” must also take account of factors such as:
• the estimation of the radioactive inventory and its dispersion: this point is important
because the concepts of half-life and specific activity are important, and one cannot
incorporate a large amount of activity of a long-lived radionuclide without raising a
problem;
• the resources contaminated and the foreseeable contamination times;
• critical groups appropriate to each situation.
Decision making in this field is a complex trade between the conclusions of the experts in the
different scientific disciplines and the sometimes subjective options taken by policy makers who are
influenced by the sociological context of the moment.
4.1.6 Conclusion and recommendations
It is recommended to abandon the term “potential radiotoxicity”, in speaking of nuclear
wastes, because it gives the illusion of a management scenario for these wastes, whereas it is merely an
inventory. It is preferable to express the inventories in Bq/t of fuel (or of heavy metal it contains) or in
Bq/TWhe for each radionuclide. In the final analysis, what is measured is Bq and not Sv, and what is
potential is the risk and not the radiotoxicity. Moreover, this would help to dispel the confusion among
non-health physicists between “doses” (equivalent dose, effective dose and committed effective dose).
To visualise the comparison of the radionuclide inventories in terms of radiotoxicity, the use
of the “radiotoxic inventory” would be preferable to that of “potential radiotoxicity”. It would be easier
to understand in so far as it preserves the correct notion of an inventory, while implicitly incorporating
the weighting coefficients used in health physics. The evaluation of the risk in separation/transmutation
must be based on safety analyses over time, which account for the different aspects: plant, interim
storage and disposal. This risk must be compared with that of other strategies which are similarly
evaluated.
4.2 Radiotoxic inventory of waste
The general strategy of introducing P&T as an additional waste management option is based
on the radiological benefit which is expected from such an option. The ranking of the actinides and
long-lived fission products can be made on the comparison of their intrinsic hazard (effective dose
coefficients, Sv/Bq) coupled with their radioactive concentrations in spent fuel or HLW (Bq/tHM). The
radioactive inventory (Bq) can also be related to drinking water standards [163] as it was defined
initially, or to the more recent ALI (annual limits of intake) for comparison of their relative radiotoxicity
[164,165].
The recent ICRP publication with a comprehensive data overview lists the effective dose
coefficients FD RN in Sv/Bq for workers [165] and the general public [166] in the nuclear field. These
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