Childhood leukaemia clusters around Sellafield and Dounreay

In 1983, a television programme identified a striking cluster of childhood leukaemia in the coastal village of Seascale, adjacent to the Sellafield nuclear complex in England. Excesses of childhood leukaemia near certain other nuclear installations in Britain were later reported during the 1980s, notably a cluster in west Thurso near Dounreay in Scotland. Detailed radiological investigations demonstrated that radiation exposures from discharged radioactive material were most unlikely to be the cause of these excesses and no serious deficiencies in these assessments have been discovered despite exhaustive searches. In 1990, a report was published suggesting that occupational radiation exposure of men before the conception of their children could be responsible for the Seascale cluster. Extensive research has not supported a causal link between paternal preconceptional radiation dose and childhood leukaemia, and the idea that radiation exposure of fathers materially increases the risk of leukaemia in offspring and could account for the clusters has now effectively been abandoned. In contrast, evidence has mounted that childhood leukaemia has an infectious basis and that unusual population mixing increases the risk of the disease. It now seems that population mixing is the explanation for the excesses of childhood leukaemia near nuclear sites and at other locations with no enhanced exposure to radiation