Inside the body, I-131 accumulates in the thyroid gland, which is an organ in the neck. People may also be exposed by breathing dust particles in the air that are contaminated with I-131. Human exposure to I-131 released from nuclear power plant accidents comes mainly from consuming contaminated water, milk, or foods. In the most severe kinds of accidents, such as the Chernobyl accident in 1986, other dangerous radioactive isotopes, such as strontium-90 (Sr-90) and plutonium-239, may also be released. The radioactive isotopes released in nuclear power plant accidents include iodine-131 (I-131), cesium-134 (Cs-134), and Cs-137. the person’s age (with those exposed at younger ages generally at higher risk of cancer).how a person comes in contact with the released radioactive materials (such as through contaminated food, water, air, or on the skin).how much radiation someone is exposed to and for how long.the specific types and quantities of radioactive materials, or isotopes, released.If the fuel and surrounding containment structures are severely damaged, radioactive materials and ionizing radiation may be released, potentially posing a health risk for people. In nuclear power plants, specially designed fuel rods and containment structures enclose the radioactive materials to prevent them, and the ionizing radiation they produce, from contaminating the environment. Additional radioactive isotopes are produced during this process. Nuclear power plants use energy released by the decay of certain radioactive isotopes to produce electricity. What are the health hazards of exposure to ionizing radiation? from cosmic rays originating in the sun and other extraterrestrial sources and from technological devices ranging from dental and medical x-ray machines to the picture tubes of old-style televisionsĮveryone on Earth is exposed to low levels of ionizing radiation from natural and technological sources in varying proportions, depending on their geographic location, diet, occupation, and lifestyle.These isotopes are also produced in nuclear reactors and nuclear weapons explosions. Radioactive isotopes occur naturally in the Earth’s crust, soil, atmosphere, and oceans. Unstable isotopes, which are also called radioactive isotopes, give off (emit) ionizing radiation as part of the decay process. from the spontaneous decay (breakdown) of unstable isotopes.Ionizing radiation can arise in several ways, including These particles and waves have enough energy to strip electrons from, or ionize, atoms in molecules that they strike. Ionizing radiation consists of subatomic particles (that is, particles that are smaller than an atom, such as protons, neutrons, and electrons) and electromagnetic waves.

Spontaneous fission accident