:: Populations living near nuclear installations
Various studies have been carried out of cancer rates in the vicinity of nuclear installations in recent years, mostly in Western Europe and North America. Doses to populations around these installations were generally several orders of magnitude lower than those to persons living near the Techa River in Russia at the time of high discharges from the Mayak plant. There is evidence of raised cancer risks in this latter group, although quantification is difficult.
There does not appear to have been a general increase in rates of adult cancers around nuclear installations. Some, but not all, studies have indicated increased rates of childhood cancers and particularly childhood leukaemia. The evidence for such increases has tended to be strongest in the vicinity of nuclear reprocessing plants; in particular, Sellafield and Dounreay in the UK and, to a lesser extent, La Hague in France. Interpretation of these studies has been hindered in part by small numbers of cases and by the ecological (correlation) study design used in many instances. Assessments of radiation doses to those living near these installations do not suggest that the raised childhood leukaemia risks can be explained on the basis of radioactive discharges. Case–control studies generally do not demonstrate clear links with habits that might give rise to enhanced environmental exposures. A case– control study around Sellafield suggested a link between childhood leukaemia and paternal occupational radiation exposure prior to conception. However, this has not been replicated in larger studies elsewhere, and may have been a chance finding. Non-radiation factors such as population mixing have been mentioned as possible explanations for the raised risks, but it is unclear whether these factors could explain all the results.
At present, specific actions are not indicated over and above existing guidelines on radiation exposures to members of the public. However, continued monitoring of environmental radioactivity and cancer rates around nuclear installations is desirable.