Radiation injury

[Merna]

Radiation injury is damage to tissues caused by exposure to ionizing radiation.

Large doses of ionizing radiation can cause acute illness by reducing the production of blood cells and damaging the digestive tract.
A very large dose of ionizing radiation can also damage the heart and blood vessels (cardiovascular system), brain, and skin.
Radiation injury due to large and very large doses is referred to as a tissue reaction. The dose needed to cause visible tissue injury varies with tissue type.
Ionizing radiation can increase the risk of cancer.
Radiation exposure of sperm and egg cells carries little increased risk of genetic defects in offspring.
Doctors remove as much external and internal (material that is inhaled or ingested) radioactive material as possible and treat symptoms and complications of radiation injury.

In general, ionizing radiation refers to high-energy electromagnetic waves (x-rays and gamma rays) and particles (alpha particles, beta particles, and neutrons) that are capable of stripping electrons from atoms (ionization). Ionization changes the chemistry of affected atoms and any molecules containing those atoms. By changing molecules in the highly ordered environment of the cell, ionizing radiation can disrupt and damage cells. Cellular damage can cause illness, increase the risk of developing cancer, or both.
Ionizing radiation is emitted by radioactive substances (radionuclides), such as uranium, radon, and plutonium. It is also produced by devices, such as x-ray and radiation therapy machines.
Radio waves, such as from cell phones and AM and FM radio transmitters, and visible light also are forms of electromagnetic radiation. However, because of their lower energy, these forms of radiation are not ionizing, and thus public exposure levels from these common sources do not damage cells. In this discussion, “radiation” refers exclusively to ionizing radiation.