Life would not exist without radiation.
The sun releases radiation and so do humans, who have naturally occurring radioactive isotopes in their bodies. What's more, the natural radiation in the environment is about the same today as it was 10,000 years ago.
Humans have also harnessed the power of radiation to use every day. In the United States, there is a 20 percent chance that the electricity used to heat and light a home comes from nuclear power. Radiation processes sewage to use as fertilizer. Radiation is used to sterilize medical supplies and contact lens solution, to gauge the thickness of sheet steel and paper and to inspect welds and airline baggage.
Americans benefit from the use of ionizing radiation in diagnostic tests and therapeutic medicine. Radioactive tracers are necessary in biology and medicine. Radiation is important for understanding the behavior of trace elements in the environment and human nutrition.
Last updated July 10, 2012, 4:00pm CDT.