Accidents at Nuclear Power Plants and Cancer Risk
1. Ionizing radiation is a form of energy that is present naturally in the environment at low levels. Natural sources of ionizing radiation include radioactive minerals in the earth and cosmic rays from outer space. Ionizing radiation is also given off, or emitted, by medical x-ray machines, by some other man-made devices, and by radioactive isotopes produced in nuclear reactors and explosions of nuclear weapons (see Question 1).
2. At high doses, ionizing radiation can cause immediate damage to a person’s body, including radiation sickness and death. Lower doses may cause cancer, usually many years later. The cancer risk depends on the amount of radiation, the type of radiation, and the parts of the body exposed (see Questions 1 and 2).
3. Accidents that cause severe damage to nuclear power plants may result in the release of radioactive materials into the environment and associated exposures to ionizing radiation. The two radioactive isotopes released in such accidents that generally pose the greatest cancer risks are iodine 131 (I-131) and cesium 137 (Cs-137) (see Question 2).
4. For decades, the National Cancer Institute has been studying groups of people who were exposed to ionizing radiation from nuclear accidents and above-ground atomic weapons explosions to learn about the cancer risks from these exposures. This information will help researchers understand and minimize the health effects of future nuclear accidents (see Questions 3, 4, and 7).
5. Cancer patients residing near nuclear power plants at the time of an accident should be relocated immediately so their treatments may continue without interruption (see Question 6).
Accidents at Nuclear Power Plants and Cancer Risk - National Cancer Institute