How Does Radiation Affect the Human Body?
Radiation is a carcinogen (kar-SIN-o-jen), which means it is a cancer-causing agent. Because radiation occurs naturally from sources such as our bodies, space, rocks, soil, and radon gas, some exposure is unavoidable. The dose that the average American is exposed to during a year is considered safe, and both small and large doses of certain types of radiation are used in health care. For example, x-rays and CT scans (computerized axial tomography) are used to diagnose illnesses, and radiotherapy (high doses of radiation targeted at tumors) is used to kill cancer cells. Exposure to very high doses of radiation, or long-term exposure to smaller amounts, however, increases the risk of injury or illness.
