|Comments on Draft Document ICRP 02/276/06
1. Item 48:
Speaking about the tissue reactions (¡§deterministic effects¡¨), it seems more preferable to use damaging cells, rather than killing cells. It is also justified by the fact that further Items 50 and 51 broach rather the topic of the damaging of cells, for instance ¡K radiation damage (serious malfunction or death) of a critical population of cells¡K; ¡Klate reactions may be a consequential type if they arise as a result of the earlier cellular damage¡K
2. Item 58:
Such effects of the cell level as adaptive response, induced genomic instability, and bystander effect deal with the low dose exposure. It seems expedient to reinforce this item with the following provision:
¡§At the low dose exposure, there are too many factors of non-radiological nature that cannot be taken into account as a priori by the researcher. On the one hand, they are able to modify radiation effects, and, on the other hand, entail the occurrence of similar ones. Apart from it, a transfer of the data from cell cultures to the population level does not seem to be sufficiently justified.¡¨
3. Items 82-85:
Speaking about genetic predisposition to cancer, it is appropriate to pay attention to the following circumstance, namely:
At some autosomal recessive hereditary diseases, such as ataxia teleangiectasia, Fanconi¡¦s anemia, Bloom¡¦s syndrome, and others, the cancer frequency is increased by hundreds or thousands times, for instance, that of leucosis at ataxia teleangiectasia is by 104 times higher than for the average population. These sick persons also rank last in the human population from the standpoint of radiosensivity, both in vitro and in vivo. Regardless of the fact that the diseases themselves are extremely rare (the frequency of ataxia teleangiectasia is 1:10000 of the new-borns), the share of heterozygous carriers of defective genes makes up several per cents. Along with increased radiosensivity, heterozygotes also have a higher cancer probability. At the same time, the ratio of ƒÑƒ}ƒÒƒncoefficients of dose dependencies was shown not to differ for sure from the one for the entire population, that making the extrapolation of these dependencies to low doses correct.
4. Items 351-357:
Overall, the goal of the new approach to radiation protection is positive. However, as was mentioned in other comments, for instance, those of R.M.Alexakhin, grave issues exist to implement it. Another thing can be mentioned in this connection, namely:
In human population the selection is negligible from the standpoint of a human as the biological species. Unlike the human, other species exist under the conditions of severe competition for the habitat and food covering both intraspecific and interspecific relations.
It is practically impossible to completely exclude these complicated interactions. Apart from it, it is appropriate to take into account that the consequences of any impacts may be harmful for single specimens and be favourable for the population or the entire ecosystem. For this stage of our knowledge development, a practical transfer to the new principles of protection seems to be premature, even if all species are investigated.