Nord-cotentin radioecological study - sensitivity and uncertainty analysis

A radioecological study has been performed by the Nord Cotentin Radioecology Group to assess the radiation-induced leukaemia risk in the Beaumont-Hague canton of the Nord-Cotentin region. Results were published in July 1999. One important figure was the number of leukaemia cases in excess for young people aged 0 to 24, living in the Beaumont-Hague canton and exposed to radioactive discharges from nuclear facilities located in the Nord-Cotentin region, that was estimated at some 0,002 for the years 1978 to 1996. This number is low in comparison with the incidence of leukaemia recorded by recent epidemiological studies for the same period (4 cases observed versus 2 expected). Nevertheless, this result caused debate, particularly because the uncertainty associated with it had not been estimated. This led to launch a study to estimate the uncertainty of the number of excess cases of leukaemia. In this paper the methodological approach retained for the sensitivity and uncertainty analysis is presented and the results are discussed. (orig.)