The measurement of radioactivity in people living near the Dounreay Nuclear Establishment, Caithness, Scotland

Abstract

In 1986, a statistically significant excess of leukaemia was reported in young people living near the Dounreay Nuclear Establishment in northern Scotland. The Committee on Medical Aspects of Radiation in the Environment (COMARE) confirmed this finding and concluded that, based on conventional dose and risk estimates, the radioactive discharges from the plant could not be held responsible. However, COMARE, recognizing the uncertainties involved in the dose and risk calculations, recommended that levels of radioactivity should be measured in the general population living near the plant. Alpha-emitting contamination has been measured by urinary 239Pu analysis and 241Am in-vivo skull measurements in 66 subjects associated with the Dounreay area and in 42 subjects living remote from reprocessing plants. Whole-body counting was employed to check for gamma ray-emitting contamination. Urinary 90Sr and chromosome abnormality analyses were also carried out on subsets of the study group. No significant inter-group differences for measurements of contamination were demonstrated for groups of leukaemia cases, siblings, parents, matched local controls and controls living remote from reprocessing plants. The findings suggest that it is unlikely that the observed increased incidence in leukaemia is due to the single factor of personal radioactive contamination from the Dounreay Nuclear Establishment.