Natural & Man-Made Sources of Radiation Exposure

Radiation is energy that is emitted as particles, rays, or waves from a single source. In large doses, radiation can have harmful effects on the human body, including radiation sickness. Radiation sickness results from prolonged exposure to ionized radiation found in a variety of radioactive chemicals and nuclear weapons and explosions. Mild radiation sickness may cause the person to experience vomiting, nausea, and hair loss. Greater exposure may cause different types of cancer, sterility, and cataracts. There are a few different sources of radiation, both natural and manufactured; these sources include the naturally produced radon, cosmic radiation, terrestrial radiation, internal radiation, and radiation from controlled sources, including x-rays and medical treatments, consumer products, and nuclear chemicals.

Natural Sources of Radiation

There are three main sources of natural radiation: cosmic radiation, terrestrial radiation, and internal sources of radiation. Cosmic radiation is a product of the sun and outer space and includes particles with positive charges and gamma radiation. The approximate amount of cosmic radiation at seas level is 26 mrem/yr; as the amount of cosmic radiation of an area increases as the elevation increased.

Terrestrial radiation is radiation emitted by elements that occur naturally in the Earth’s crust. Sources of terrestrial radiation include water, rocks, elements such as: thorium, radium, uranium. Radon, a source of alpha radiation, emits a gas that has caused major health concerns in the medical community. Radon gas is a result of decaying uranium and is known to seep through the soil and build up around homes and other buildings. People are exposed to approximately 200 mrem/yr from radon in and around their homes and industrialized environments. The human body accounts for only a small portion of naturally occurring radiation. The body emits about 40 mrem/yr; a very small fraction compared to other sources.

Radon

  • Radon: A very thorough site regarding radon outlining the average exposure, sources of radon, health effects, mitigation strategies, and EPA recommendations regarding radon.
  • Radon and Cancer: An explanation of radon, how people are generally exposed, and whether the exposure to radon increases the risk of cancer in individuals.
  • Radon in Water: Introduces the fact that there is radon in groundwater in North Carolina, as well as most places, the health effects of the radon, and how this is treated.
  • Radon in the Home: This site concentrates on the dangers of radon in the home, beginning with a description of radon, going through ways to test for radon, and ending with ways to reduce radon in the home.
  • Radon: radon for kids: Directed towards kids, this page takes a simplistic view of radon and its effects on the environment and humans.

Cosmic Radiation

  • The Cosmic Background Radiation: Article with images and diagrams explaining the evidence of cosmic radiation in the universe and how this fits in with the “big bang” theory.
  • What Are Cosmic Rays?: An extensive site documenting the discovering of cosmic rays, the way cosmic rays are studied, different types of cosmic radiation, etiology of the rays, and the way the radiation detectors work.
  • ARPANSA – Cosmic Radiation Exposure: Discussion on cosmic radiation that may be encountered during domestic airplane flight, documenting the exposure and possible health risks associated with it.
  • Cosmic Rays: Learn more about the elements and particles in cosmic rays.

Terrestrial Radiation

Internal Radiation

Man-Made Sources of Radiation

While the human body does not produce a significant amount of radiation, the things we produce do. Radiation is commonly found in medical items, and is frequently used in radial treatment and x-ray scanning. Outside the controlled use of radiation, consumer products and the production of consumer products also produce a considerable amount of radiation. Items such as televisions, computers, microwaves, and appliances account for 10 mrem/yr. Nuclear weapons manufacturing and testing also influences radiation exposure. Weapons testing from the 1950s and 60s still accounts for approximately 2 mrem/yr from residual sources and byproducts.

Medical X-rays

  • Medical X-Rays: The U.S. Department of Health & Human Services explains the use, benefits, and risks of medical radiation.
  • X-Ray Radiation Safety: It is important to practice safety when around x-ray radiation, learn proper safety measures here.

Nuclear Medicine

  • Nuclear Medicine: Learn about the uses of and advances in the field of nuclear medicine.

Consumer Products

  • Radiation Emitting Devices: This Canadian act is provides consumers with important information regarding radiation and consumer products.

Other Man-Made Sources

  • Radiation Threat: Learn to do in the event of a “Dirty Bomb” or radiation threat.
  • Nuclear Waste: A detailed article about nuclear waste and the danger it poses to the environment.