High dose rate exposures to ionizing radiation are thought to be more dangerous than low dose rate exposures. A cohort study of nuclear industry workers from France, the United Kingdom, and the United States suggest there is a linear relationship between increasing radiation exposure and cancer rates. The study was published online in BMJ.
High dose rate exposures to radiation are considered more dangerous than low dose rate exposures. But is there an association between extended exposure to low dose radiation and an increase in risk for solid cancers?
An international team of researchers conducted a cohort study of 308 297 nuclear industry workers from France, the United Kingdom, and the United States. The team linked detailed monitoring data on external exposure to ionizing radiation with death registries.
The researchers estimated excess relative rate per Gy of radiation for mortality from cancer. Average cumulative dose colon dose for exposed workers was 20.9 mGy (media 4.1 mGy).
Mortality from all cancers excluding leukemia was estimated to increase by 48% per Gy, lagged by 10 years. Results were similar across all solid cancers (47% [18% to 79%]), and within each country.
These results suggest a linear relationship between an increase in cancer rates and increasing radiation exposure.
1. Richardson DB, Cardis E, Daniels RD, et al. Risk of cancer from occupational exposure to ionizing radiation: retrospective cohort study of workers in France, the United Kingdom, and the United States (INWORKS). BMJ. 2015;351:h5359.