Join the movement.
Complete the Catch assessment and discover your cancer score now.
You may have heard that radiation exposure can cause health problems, but it may surprise you to learn how prevalent radiation really is. Everyone on earth is exposed to radiation on a daily basis, primarily from sources outside of our control[1], such as radon in the air, cosmic radiation (from space), and even radiation that naturally occurs in the human body.
When we talk about radiation exposure, there are two main types of radiation to consider:
People are exposed to ionizing radiation via both natural and manmade sources. Natural sources of exposure–i.e., those that can’t be completely controlled for–include[2]:
Your exposure to radon and cosmic radiation can vary significantly. Radon gas forms naturally, and can become trapped in buildings, concentrating your exposure. Testing your home or workplace is the only way to know your exposure level [4]. Cosmic radiation comes from space, but most of it is absorbed by the earth’s atmosphere. However, living at higher elevations, or jobs that require significant travel–particularly long-haul flights and flights over the poles–can increase your exposure. This is due to the fact that less of the radiation is dispersed by the atmosphere at higher elevations.
Man-made sources of ionizing radiation account for an estimated 48% of the average individual’s exposure[1]. Man-made sources include:
The exposure from each of these tests can vary widely based on the type of imaging being performed, the machine used, the duration of the scan, and the size of your body[5]. It should be noted that in real terms, the amount of exposure from these tests is low. For reference, the amount of ionizing radiation from a single cross-country flight ranges from 0.02-0.05 mSv[6]
Like ionizing radiation, non-ionizing radiation has both natural and manmade sources. Ultraviolet radiation from the sun (or from artificial sources such as tanning beds and black lights) is the highest-frequency form of non-ionizing radiation, and the only form of non-ionizing radiation that has been definitively linked with cancer[7].
Radiofrequency and microwave radiation are also common, and can be both naturally occurring or manmade. Some common sources of radiofrequency include[8]:
Both ionizing and non-ionizing radiation can pose significant health risks, though the risks from ionizing radiation are better established and much more serious.
There are many ways to reduce exposure to both ionizing and non-ionizing sources of radiation:
Radiation exposure, particularly exposure to ionizing radiation, is convincingly tied to an increased risk of cancer and other serious health issues. Reducing your exposure when possible is recommended.
[1] Radiation Sources and Doses. Environmental Protection Agency. November 22, 2024.
[2] About Ionizing Radiation. Centers for Disease Control. February 19, 2024.
[3] Facts About Radiation from Space (Cosmic Radiation). Centers for Disease Control. February 20, 2024.
[4] Radon and Your Health. Centers for Disease Control. February 16, 2024.
[5] Radiation Risk from Medical Imaging. Harvard Health Publishing. September 30, 2021.
[6] Cosmic Radiation. US Environmental Protection Agency. October 28, 2024.
[7] Facts About Ultraviolet Radiation. Centers for Disease Control. February 20, 2024.
[8] Radiofrequency (RF) Radiation. American Cancer Society. October 28, 2022.
[9] Ionising radiation and cancer risks: What have we learned from epidemiology? International Journal of Radiation Biology. October 8, 2009.
[10] Toxicological Profile for Ionizing Radiation. Agency for Toxic Substances and Disease Registry. September 3, 1999.
[11] Accidents at Nuclear Power Plants and Cancer Risk. National Cancer Institute. May 12, 2022.
[12] Non-Ionizing Radiation from Wireless Technology. Environmental Protection Agency. November 12, 2024.