Leukaemia and paternal radiation exposure.

OBJECTIVE

Recently, Gardner and colleagues inferred, from a case-control study of leukaemia incidence in young people near the Sellafield nuclear facility in West Cumbria, that an increase near Sellafield was real, and was probably caused by occupational exposure of the father to ionising radiation at the Sellafield plant. The intent of this paper is to dispute that attribution, and to suggest that confirmation of such an alarming and prejudicial conclusion should precede its dissemination. MATERIAL CONSIDERED: Critical comment is limited to the paper by the Gardner group presenting their results, the accompanying paper outlining their methods, a review from Mathews that provides some support for the Gardner proposal by suggesting a pathogenetic mechanism, and some observations on inherited tumours by Nomura that are quoted by Gardner et al. and Mathews in support of their beliefs. Other material quoted is from the general medical literature of the past 20 years relating to radiation biology, mutagenesis and carcinogenesis with some relevance to the Gardner contention; it is not exhaustive.

MAIN RESULTS

Statistical arguments suggest that it is almost impossible to be sure that a specific leukaemia "cluster", such as that near Sellafield, is not a chance finding. The study by Gardner et al. provides only weak statistical evidence for an association between leukaemia in children and parental occupational radiation exposure at Sellafield. The postulate of a causal relation between parental exposure at Sellafield and leukaemia in progeny is incompatible with what is known of the role of genetic mechanisms in leukaemia, with current views on the quantitative relation between radiation dose and mutagenetic effect, and with observations on the children of people exposed to radiation by the nuclear bombs used in Japan in 1945.

CONCLUSIONS

The suggestion that occupational exposure to ionising radiation of a father may be responsible for an increased risk of leukaemia in his children cannot be substantiated. It would be proper to seek confirmation from other groups of occupationally exposed persons before undertaking precipitous, and inevitably disturbing, action to remedy the supposed problem.