A study found that the Sellafield workers' children born in Seascale (the village near the Sellafield nuclear reprocessing plant) ran an average 15 times higher risk of developing leukaemia and non--Hodgkins lymphoma and that the Sellafield workers' children outside Seascale ran an average twofold higher risk. The risks rose in line with the amount of exposure their fathers had experienced prior to the children's conception. These findings confirmed Martin Gardner's 1989 findings.

The lead researchers, Heather Dickinson and Louise Parker from the North of England Children's Cancer Research Unit also re-examined the evidence for the controversial External Workers' Virus hypothesis (see below) and considered it inadequate.

In 1989 the late Professor Martin Gardner found a direct link between a child's risk of developing leukaemia and the amount of radiation to which their fathers had been exposed whilst working at Sellafield. He found up to an eightfold increased risk.

The finding was rubbished by the nuclear industry whose scientists dreamed up several other explanations for the child leukaemia clusters identified within a few miles of the plant. One of these was that workers moving into the area to build and work at Sellafield had brought with them viruses to which the local inhabitants had little resistance (leukaemia can be caused by viruses). What the industry scientists did not explain was why other major building projects involving external workers around the world had not shown similar leukaemia clusters.

Work by the Institute of Evolution and the Kaput Holim National Cancer Control Centre in Israel and the Research Centre for Radiation Medicine in the Ukraine gives strong support to Martin Gardner's theory. They found a sevenfold increase in DNA mutation in children born to fathers who had worked as 'liquidators' (clearer uppers) after the Chernobyl accident. The mutation increases the risk of cancer as well as of genetic instability in the children's own descendants, and occurs even at the lowest levels of exposure.