FATHERS OCCUPATIONAL EXPOSURE TO RADIATION AND THE RAISED LEVEL OF CHILDHOOD LEUKEMIA NEAR THE SELLAFIELD NUCLEAR-PLANT

The first indications that childhood leukemia rates may be raised near the Sellafield nuclear plant in West Cumbria, England, came from largely anecdotal evidence in a television program "Windscale: The Nuclear Laundry" shown during 1983. During subsequent years, various epidemiological studies have investigated the claim in more detail. Geographical analyses of childhood leukemia incidence in the northern region and mortality in England and Wales using routinely available data made the first contribution. As a result, it was confirmed that leukemia rates in the area, particularly the neighboring village of Seascale, were high compared to other districts, although not totally extreme. Cohort studies of children born in Seascale or attending schools in Seascale were carried out to resolve some of the difficulties of interpretation of geographical analysis. Cohort studies indicated that the excess of leukemia was concentrated among children born in Seascale and was not found among those moving in after birth and suggested that any causal factors may be acting before birth or very early in life. A case-control study of leukemia (and lymphoma) among young people in West Cumbria has examined potentially important individual factors in detail. The study demonstrated a relationship between the raised incidence of leukemia in children and father's recorded external radiation dose during work at Sellafield before his child's conception. The association can effectively explain statistically the observed geographical excess.