What is the estimated lifetime risk of fatal cancer from radiation exposure of 1 Sv?

The estimated lifetime risk of fatal cancer from radiation exposure of 1 Sv is often regarded as approximately a 5% increased risk. This value is derived from epidemiological studies, particularly those involving atomic bomb survivors and various occupational exposure populations. The linear no-threshold model is commonly used to extrapolate risks, suggesting that even low doses of radiation have the potential to increase cancer risk linearly.

The assumption of a 5% increase in cancer risk per Sv is based on statistical models that take into account the background rates of cancer and the additional risk posed by ionizing radiation. It reflects the consensus in health physics and radiation protection fields regarding the correlation between radiation exposure and cancer incidence.

Higher percentages for lifetime risk, such as 10% or more, do not align with established findings from major studies and represent overestimations based on current data. Similarly, suggesting a lower percentage such as 2% does not reflect the comprehensive understanding derived from detailed research on radiation effects. Therefore, the 5% increased risk is the widely accepted figure in the context of radiation exposure at the level of 1 Sv.