The latest update to the International Nuclear Workers Study (INWORKS) enhances the understanding of the link between low-dose ionising radiation and mortality from haematological malignancies. This comprehensive study examines associations between radiation exposure and deaths due to various blood cancers, offering critical insights into radiation protection standards.
The study involved a cohort of 309,932 radiation-monitored workers from France, the UK, and the USA, spanning from January 1, 1944, to December 31, 2016. These workers, predominantly male (87%), accumulated a total of 10.72 million person-years of follow-up. They were monitored for external radiation exposure, and the research focused on radiation dose-related mortality for a range of haematological cancers, including leukaemia, myelodysplastic syndromes, lymphomas, and multiple myeloma.
Key findings revealed a significant linear association between cumulative radiation dose to the red bone marrow and mortality from leukaemia, excluding chronic lymphocytic leukaemia (CLL). The excess relative rate (ERR) per Gy of radiation dose was calculated at 2.68 (90% CI 1.13 to 4.55), based on 771 cases. This association persisted irrespective of neutron exposure or monitoring status. Specific types of leukaemia, such as chronic myeloid leukaemia, showed even stronger associations, with an ERR of 9.57 (4.00 to 17.91) for 122 cases.
Other malignancies, including multiple myeloma, also displayed a positive association with radiation exposure (ERR 1.62, 0.06 to 3.64). However, the study found no significant correlation with acute lymphoblastic leukaemia, CLL, non-Hodgkin lymphoma, or Hodgkin lymphoma mortality.
Despite these associations, the overall risk remains low, with an estimated excess of one leukaemia death per 10,000 workers over 35 years. These findings underscore the need for continued refinement of radiation protection standards and contribute valuable data to the broader discussion on radiation safety and public health.
Katie Wright, EMJ
Reference
Leuraud K et al. Leukaemia, lymphoma, and multiple myeloma mortality after low-level exposure to ionising radiation in nuclear workers (INWORKS): updated findings from an international cohort study. Lancet Haematol. 2024;DOI:10.1016/S2352-3026(24)00240-0.