Risk of cancer after low doses of ionising radiation: retrospective cohort study in 15 countries
- PMID: 15987704
- PMCID: PMC558612
- DOI: 10.1136/bmj.38499.599861.E0
Risk of cancer after low doses of ionising radiation: retrospective cohort study in 15 countries
Abstract
Objectives: To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental, occupational, and medical diagnostic exposures.
Design: Multinational retrospective cohort study of cancer mortality.
Setting: Cohorts of workers in the nuclear industry in 15 countries.
Participants: 407 391 workers individually monitored for external radiation with a total follow-up of 5.2 million person years.
Main outcome measurements: Estimates of excess relative risks per sievert (Sv) of radiation dose for mortality from cancers other than leukaemia and from leukaemia excluding chronic lymphocytic leukaemia, the main causes of death considered by radiation protection authorities.
Results: The excess relative risk for cancers other than leukaemia was 0.97 per Sv, 95% confidence interval 0.14 to 1.97. Analyses of causes of death related or unrelated to smoking indicate that, although confounding by smoking may be present, it is unlikely to explain all of this increased risk. The excess relative risk for leukaemia excluding chronic lymphocytic leukaemia was 1.93 per Sv (< 0 to 8.47). On the basis of these estimates, 1-2% of deaths from cancer among workers in this cohort may be attributable to radiation.
Conclusions: These estimates, from the largest study of nuclear workers ever conducted, are higher than, but statistically compatible with, the risk estimates used for current radiation protection standards. The results suggest that there is a small excess risk of cancer, even at the low doses and dose rates typically received by nuclear workers in this study.
Figures
References
-
- BEIR V. Committee on the Biological Effects of Ionizing Radiation. The effects on populations of exposure to low levels of ionizing radiation. Washington, DC: National Academy of Sciences, 1990.
-
- International Commission on Radiological Protection ICRP. Recommendations of the international commission on radiological protection. Oxford: Pergamon Press, 1991. (ICRP publication 60.)
-
- United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Sources and effects of ionizing radiation. New York: United Nations, 2000.
-
- Berrington de González A, Darby S. Risk of cancer from diagnostic X-rays: estimates for the UK and 14 other countries. Lancet 2004;363: 345-51. - PubMed
-
- IARC Study Group on Cancer Risk among Nuclear Industry Workers. Direct estimates of cancer mortality due to low doses of ionising radiation: an international study. Lancet 1994;344: 1039-43. - PubMed
Publication types
MeSH terms
Grants and funding
LinkOut - more resources
Full Text Sources
Other Literature Sources
Medical