Uncertainties in Seascale internal dose estimates are sufficiently large that it would be unwise to rule out radiation as a contributory factor for the effects seen at Seascale, as concluded by several CERRIE members. (Committee Examining Radiation Risks of Internal Emitters)
CERRIE was established by the Government in 2001 because of concern that public perception of the risks of exposure to radiation from radionuclides deposited within the body may be at variance with official scientific advice. In 2001, the then Environment Minister, Michael Meacher announced that the working group would “consider present risk models for radiation and heath that apply to exposure from internal radionuclides in the light of recent studies and to identify any further research that may be needed”.
In the Committee’s Draft Final Report, due to be published in September but leaked to CORE, the Committee agreed that the ICRP (Int. Cttee of Radiolgical Protection) models could be wrong by a factor of 2 or 3 for radionuclides for which good data exist, and by a factor of well over 10 for Plutonium and Americium. Almost half the Committee members were of the view that recently discovered biological mechanisms (genomic instability and bystander effect) were not adequately reflected in ICRP models and that these underestimates could account for some epidemiological findings especially at Seascale.
A CORE spokesperson said today: “After 20 years of BNFL insisting that radiation from Sellafield had nothing to do with the Seascale leukaemia cases, we welcome the findings of the Committee that there is still a great deal of uncertainty about the health effects of internal radiation like plutonium and americium.
The acknowledgement that they don’t know everything and their recommendations for further research into internal dose, can only be good news for BNFL workers and for us living around the plant. With the annually rising radiation dose from Americium to the critical group as a result of Sellafield’s unacceptably high historial plutonium discharges, we need to feel protected and as far as we’re concerned, uncertainty justifies much further research”.
The CERRIE Committee’s recommendations for further work include studies of nuclear workers, Chernobyl clean-up workers. It considers that a valuable complement to epidemiological studies of those exposed to internal emitters is the measurement of radionuclides in urine or in teeth (removed for orthodontic purposes) from members of the public resident in various parts of the country, to determine general levels of radionuclides around, and distant from, nuclear sites.