People are concerned about the potential hazards and risks of human health effects from radiation exposure. To address those concerns, we must look at what radiation is, what the potential health effects might be, how potential health risks can be assessed and managed, and how these risks could be compared to the benefits of using radioactive materials. Ionizing radiation can give off enough localized energy to tissue to remove electrons from atoms and molecules in its path, ionizing the material. Electromagnetic ionizing radiation includes x-rays and gamma rays. Ionizing radiation comes from natural sources such as radioactive elements in soil or bedrock.
Examples are radon, uranium, radium, and potassium isotopes.
Other natural radiation sources include cosmic radiation, which comes from the sun and stars, and internal radiation from the water and food we consume and the air we breathe. Nonionizing radiation, such as ultraviolet radiation, simply transfers energy but does not ionize other atoms. Society has also created sources of ionizing radiation. Radioactive substances differ in the type of radiation they emit and the strength or energy level of that radiation. As radiation is emitted, the substance loses part of its total amount of radioactivity.