These radioactive and non-radioactive elements are used in building and maintaining our bodies. Natural radioisotopes continually expose us to radiation. The table below identifies the amount of radioactivity from potassium contained in about grams of different food products.
A becquerel is a unit of radioactivity, equal to one transformation decay per second. CRC Press The human body also contains several radioactive isotopes. The table below contains a list of some of the isotopes naturally found in the body.
Return to table 2 note 1 referrer. Academic Press, Inc. Return to first table 2 note 2 referrer. Return to first table 2 note 3 referrer.
Return to table 2 note 4 referrer. The atmospheric testing of atomic weapons from the end of the Second World War until as late as released radioactive material, called fallout, into the air. As the fallout settled to the ground, it was incorporated into the environment. Much of the fallout had short half-lives and no longer exists, but some continues to decay to this day.
People and the environment receive smaller and smaller doses from the fallout every year. Radiation has many uses in medicine. The most well known use is in X-ray machines, which use radiation to find broken bones and diagnose disease.
X-ray machines are regulated by Health Canada and provincial authorities. Another example is nuclear medicine, which uses radioactive isotopes to diagnose and treat diseases such as cancer. These applications of nuclear medicine, as well as the related equipment, are regulated by the CNSC. The CNSC also licenses those reactors and particle accelerators that produce isotopes destined for medical and industrial applications.
Radiation has a variety of industrial uses that ranges from nuclear gauges used to build roads to density gauges that measure the flow of material through pipes in factories. It is also used in smoke detectors and some glow-in-the dark exit signs, and to estimate reserves in oil fields.
Radiation is also used for sterilization in which large, heavily shielded irradiators are used. Official websites use. Share sensitive information only on official, secure websites. JavaScript appears to be disabled on this computer. Please click here to see any active alerts. Sources of radiation radiation Energy given off as either particles or rays. Some are natural and some are man-made. The amount of radiation absorbed by a person is measured in dose.
A dose is the amount of radiation energy absorbed by the body. See Radiation Basics for information about dose. Click the image below to enlarge the periodic table and see which exist only as radioactive isotopes and are sources of radiation. Background radiation Background radiation Radiation that is always in the environment.
The majority of background radiation occurs naturally and a small fraction comes from man-made elements. Man-made radiation sources are classified onto radionuclide radiation sources and generators of ionising radiation. The mankind has created the hundreds of artificial radionuclides and got mastered to use the atomic energy both for military and for civil purposes —for energy production, in health care, etc. These activities increase exposure as individuals as well as the Earth population at all.
Individual doses of different people from man-made sources vary in a broad band. In majority of cases these doses are negligible, but sometimes the technogenic exposure has intensity that in thousands times more than natural one. But, it should be noted, that doses formed by technogenic sources are easier to be controlled than doses related to radioactive sediments from nuclear bangs and accidents at NPPs, as well as the doses predetermined by cosmic and on-Earth natural radiation sources.
There multiple and wide uses of man-made sources that one may encounter with. They are:. In relation to exposure from man-made sources the two distinct groups of people are considered:. Medical procedures , such as X-rays diagnostics, nuclear medicine, and radiation therapy, are the most significant contributors in man-made exposure by ionising radiation to the public.
To a lesser degree, members of the public are exposed to radiation from consumer products, building materials, combustible fuels, X-ray security systems, etc. For more information on radon, click here. Naturally occurring radioactive elements such as carbon, potassium, uranium, thorium, and radium can be found in the soil and find their way into our food and drinking water and can be ingested. You can also ingest radon through the water supply. However, ingesting radon poses less of a threat than inhaling it.
Radon in groundwater can also contribute to radon levels in indoor air. On average, a person in the United States inhales enough radioactive materials to cause a radiation dose of 2.
This is mostly in the form of radon, which is the largest source of natural radiation exposure. This yearly amount of radiation is similar to the amount of radiation from twenty chest x-rays.
The overall levels of ingested radioactive materials are low for most people. On average, a person in the United States ingested enough natural sources of radiation to cause a small dose of about 0. This yearly amount of radiation is similar to the amount of radiation from two chest x-rays. Unless food products are contaminated as the result of a radiation emergency , levels of ingested radioactive material in the environment are low and are unlikely to affect human health.
Inhaled radioactive material in the form of radon could affect health, and radon levels in buildings should be tested and fixed if they are elevated. The amounts of radon you are exposed to may differ depending on where you live.
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