Ages at the Time of Radiation Exposure and Risks by Type of Cancer

These figures show excess relative risks of developing cancer (values indicating how cancer risks have increased among a group of people exposed to radiation compared with a group of non-exposed people) per gray as of age 70, using the results of the surveys targeting atomic bomb survivors.

For example, the excess relative risk of developing solid cancer as a whole for the age group of 0 to 9 years old is approx. 0.7, which means that the excess relative risk increases by 0.7 among a group of people exposed to 1 Gy compared with a group of non-exposed people. In other words, supposing the risk for a group of non-exposed people is 1, the risk for a group of people aged 0 to 9 who were exposed to 1 Gy increases by 1.7 times. The excess relative risk of developing solid cancer as a whole for people aged 20 or older is approx. 0.4 and the risk for a group of people exposed to 1 Gy will be 1.4 times larger than the risk for a group of non-exposed people.

As shown in the figures above, risks differ by age at the time of radiation exposure and type of cancer.
(Related to p.99 of Vol. 1, “Relative Risks and Attributable Risks”)

• Included in this reference material on March 31, 2013
• Updated on March 31, 2019