on the risk of dying from cancer have been based primarily on studies of survivors of atomic bombs dropped on Japan at the end of the Second World War.
The researchers therefore tracked and analyzed deaths among 309,932 workers in the nuclear industry in the UK, France, and the US for whom individual monitoring data for external exposure to ionizing radiation were available. They estimated that this risk increased by 52% for every unit of radiation workers had absorbed. A dose of one Gray is equivalent to a unit of one Joule of energy deposited in a kilogram of a substance.
Similarly, restricting the analysis only to workers hired in more recent years when estimates of occupational external penetrating radiation dose were more accurate also increased the risk of death from solid cancer per unit Gy absorbed.