U.S. National Library of MedicineNational Institutes of Health
Skip navigation
MedlinePlus Trusted Health Information for You MedlinePlus Trusted Health Information for You MedlinePlus Trusted Health Information for You
Contact Us FAQs Site Map About MedelinePlus
español

Printer-friendly version E-mail this page to a friend
Photograph of a radioactive warning sign

Radiation is energy that travels in the form of waves or high-speed particles. It occurs naturally in sunlight and sound waves. Man-made radiation is used in X-rays, nuclear weapons, nuclear power plants and cancer treatment.

If you are exposed to small amounts of radiation over a long time, it raises your risk of cancer. It can also cause mutations in your genes, which you could pass on to any children you have after the exposure. A lot of radiation over a short period, such as from a radiation emergency, can cause burns or radiation sickness. Symptoms of radiation sickness include nausea, weakness, hair loss, skin burns and reduced organ function. If the exposure is large enough, it can cause premature aging or even death. You may be able to take medicine to reduce the radioactive material in your body.

Environmental Protection Agency

Start Here