Mortality in the French cohort of nuclear workers

International audiencePopulations of nuclear workers are particularly relevant to study health effects of protracted exposures to low doses at low dose-rates of ionizing radiation. In France, a cohort of nuclear workers employed by the Commissariat à l'énergie atomique et aux énergies alternatives (CEA), AREVA Nuclear Cycle (AREVA NC), or Électricité de France (EDF), and badge-monitored for external radiation exposure, has been followed-up for several decades. Annual exposure to penetrating photons was reconstructed for each worker. Standardized mortality ratios were calculated using national mortality rates as the reference. Estimates of radiation dose-mortality associations were obtained using linear excess relative risk models. Mortality of 59 004 workers was followed-up between 1968 and 2004, for an average of 25 years. The mean cumulative photon Hp(10) dose was 18.4 mSv in the whole cohort (median value 2.1 mSv) and 25.7 mSv among exposed workers. At the end of the follow-up, workers were 56 years old on average and 6310 workers had died. A strong healthy worker effect was observed. Estimated dose-risk relationships were consistent with those from other worker studies for all solid cancers and leukaemia excluding chronic lymphocytic leukaemia, but remained associated to a large uncertainty. This cohort is the most informative study ever conducted in France among nuclear workers. © EDP Sciences 2017