nuclear RADIATION: Hazardous
The radiation produced by nuclear reactions interacts with living tissue in many ways depending on the type of radiation. This radiation includes high-energy, charged particles (alpha and beta), neutrons of various energies, and photons (gamma and x-rays). In addition to this primary radiation, fission also produces radioactive isotopes of many elements, which in turn can emit particles and photons, known as secondary radiation. Many of these isotopes, such as strontium and iodine, can enter the body, where they replace nonradioactive elements and remain there emitting ionizing radiation. In many ways, the presence of these radioactive isotopes is more insidious than direct radiation from external sources that is more easily detected and reduced by proper shielding.