Every day, people are exposed to radiation from natural sources (such as radon and solar and ultraviolet radiation) and man-made sources (such as cell phones, electromagnetic fields and medical radiation).
Radiation is energy that travels through space in the form of waves or particles. There are two types of radiation: ionizing and non-ionizing.
Ionizing radiation has enough energy to break chemical bonds between molecules or to form charged molecules (cause ionization). This means that ionizing radiation is strong enough to damage cells and DNA and strong enough to increase the chance of developing cancer.
Sources of ionizing radiation exposure include:
- natural background radiation (sources of exposure include cosmic rays from the solar system and radioactive materials in the soil and rocks)
- background radiation from human activities (includes testing and using nuclear weapons as well as generating nuclear power)
- medical radiation
Non-ionizing radiation isn’t as strong as ionizing radiation, and it doesn’t have enough energy to break bonds between molecules. But being exposed to some types of non-ionizing radiation can still harm you.
Sources of non-ionizing radiation exposure include:
- radiofrequency fields (including cell phones, cell phone towers and microwave ovens)
- electromagnetic fields (including power lines and household appliances)
- ultraviolet (UV) rays (including the sun and indoor tanning beds)