Background There is much uncertainty about the risks of leukaemia and lymphoma after repeated or protracted lowdose
radiation exposure typical of occupational, environmental, and diagnostic medical settings. We quantifi ed
associations between protracted low-dose radiation exposures and leukaemia, lymphoma, and multiple myeloma
mortality among radiation-monitored adults employed in France, the UK, and the USA.
Methods We assembled a cohort of 308 297 radiation-monitored workers employed for at least 1 year by
the Atomic Energy Commission, AREVA Nuclear Cycle, or the National Electricity Company in France,
the Departments of Energy and Defence in the USA, and nuclear industry employers included in the
National Registry for Radiation Workers in the UK. The cohort was followed up for a total of 8·22 million personyears.
We ascertained deaths caused by leukaemia, lymphoma, and multiple myeloma. We used Poisson regression
to quantify associations between estimated red bone marrow absorbed dose and leukaemia and lymphoma
Findings Doses were accrued at very low rates (mean 1·1 mGy per year, SD 2·6). The excess relative risk of leukaemia
mortality (excluding chronic lymphocytic leukaemia) was 2·96 per Gy (90% CI 1·17–5·21; lagged 2 years), most
notably because of an association between radiation dose and mortality from chronic myeloid leukaemia (excess
relative risk per Gy 10·45, 90% CI 4·48–19·65).
Interpretation This study provides strong evidence of positive associations between protracted low-dose radiation
exposure and leukaemia.
Klervi Leuraud, David B Richardson, Elisabeth Cardis, Robert D Daniels, Michael Gillies, Jacqueline A O’Hagan, Ghassan B Hamra, Richard Haylock,
Dominique Laurier, Monika Moissonnier, Mary K Schubauer-Berigan, Isabelle Thierry-Chef, Ausrele Kesminiene
Institut de Radioprotection et de Sûreté Nucléaire, Fontenayaux-Roses, France (K Leuraud PhD, D Laurier PhD);
Department of Epidemiology, University of North Carolina, Chapel Hill, NC, USA (D B Richardson PhD);
Center for Research in Environmental Epidemiology, Barcelona, Spain (Prof E Cardis PhD);
Universitat Pompeu Fabra, Barcelona, Spain (Prof E Cardis);
CIBER Epidemiología y Salud Pública, Madrid, Spain (Prof E Cardis);
National Institute for Occupational Safety and Health, Cincinnati, OH, USA (R D Daniels PhD, M K Schubauer-Berigan PhD);
Public Health England Centre for Radiation, Chemical and Environmental Hazards, Chilton, UK (M Gillies MSc,J A O’Hagan HNC, R Haylock PhD);
Department of Environmental and Occupational Health, Drexel University School of Public Health, Philadelphia, PA, USA (G B Hamra PhD);
International Agency for Research on Cancer, Lyon, France (M Moissonnier BSc, I Thierry-Chef PhD, A Kesminiene MD)
Dr Klervi Leuraud, Institute for Radiological Protection and Nuclear Safety, Radiation Protection Division – Radiological Protection and Health, Radiobiology and Epidemiology Department, IRSN/PRP-HOM/SRBE, BP 17, Fontenay-aux-Roses Cedex, France