The Committee considered another paper on non-cancer effects from external radiation including effects on the developing human brain, cataracts of the eye lens, and late deterministic effects in children, ie effects other than mortality. The doses for these effects were high (>1 Gy) although a recent Swedish paper reported adverse effects on intellectual development at doses down to 100 mSv. The Committee estimated that, in terms of absolute risk, the lifetime risk due to radiation may be around 10% at 1 Sv for non-cancer mortality for those exposed as children, i.e. roughly half the corresponding value for solid cancer mortality. For people exposed at age 50, the lifetime risks for non-cancer and for solid cancer mortality may be similar (i.e. around 3% to 4% at 1 Sv). UNSCEAR (2000) had not reported clear evidence of these effects from internal radiation, however a number of reports did exist according to a Committee member and these were circulated.


The Committee considered three draft chapters for their Final Report. These included chapter 2 on radiation risks of internal emitters, chapter 3 on evidence from radiation biology, and chapter 4 on evidence from epidemiology. It was agreed that the conclusions and recommendations should be at the end of the report, rather than after each chapter. It was also agreed to have separate annexes for alpha emitters, as well as for auger emitters and tritium in chapter 2 on risks.


The Committee discussed correspondence on the issue of radon. The Committee recognised that they had not considered the matter of radon in detail. This was because radon doses and risks had been comprehensively examined in BEIR VI in 1999, and there were not large deviations in the findings from many studies. Also radon exposures and risks in the UK were currently under review by the NRPB's Advisory Group on Ionizing Radiation (AGIR). The Committee felt that there was little they could usefully add to these comprehensive examinations, especially in view of its own heavy work programme and there being no disagreements amongst members on the current approaches.


The Committee considered a number of papers on epidemiology studies of test veterans. In essence, the arguments made by one member about high radiation exposures and effects had been countered in a paper by another member. As these refutations had not been answered the arguments were considered to be unsubstantiated. The Committee did not consider the matter further.


The Committee considered a report of the latest meeting of their sub Committee on Epidemiology.

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