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Thorium is a natural, radioactive element. In the environment, Thorium is present in combination with other metals, such as silicon. Small amounts of thorium are found in all rocks, in soil, in water, in plants and in animals. Soil contains an average of about 6 parts of thorium per million parts of soil (6 ppm). More than 99% of the natural thorium is present in the form of Th-232 (232Th). The 232Th is split into two parts, a small part called "alpha radiation" and a larger part called "cleavage product". The cleavage product is also unstable and is still cleavable and a series of subsequent cleavage products eventually results in a stable product. During these cleavage processes, radioactive substances including radium and radon are produced.

Thorium is used in the production of ceramic and metal alloys used in the gas industry, aerospace industry and nuclear reactors. Thorium can also be used as fuel for nuclear power generation. Thorium is a radioactive substance naturally present in the environment. It has been shown to cause lung, pancreatic, and blood cell cancers in workers exposed to high levels of thorium in the air.

How does thorium enter the environment?
  • Thorium is a natural part of the environment.
  • Thorium is converted very slowly to other radioactive substances. It takes approximately 14 billion years for half of Thorium-232 to change to new forms.
  • As rocks are eroded by air and water, thorium and all other rock components become part of the soil.
  • Thorium in the soil can be moved to rivers and lakes.
  • Dust and volcanic eruptions are the natural sources of thorium in the air.
  • Combustion of carbon can release small amounts of thorium into the air.
  • Mines that extract thorium-containing rocks or industries that process thorium-containing products may also release thorium into the environment.
How is one exposed to thorium?
  • All have been exposed to small amounts of thorium from air, water and food.
  • By breathing air near the facilities where minerals containing uranium, phosphorus or tin are processed.
  • Residents of houses built on ground with high levels of thorium.
  • Workers in the uranium, thorium, tin and phosphate mining industries and in the metal manufacturing industries may be exposed to higher levels of thorium.
  • Living near radioactive waste disposal sites.
How can thorium affect health?

Studies of workers in thorium processing industries have shown that inhalation of high thorium dust concentrations results in an increased likelihood of lung disease. People who inject Thorotrast, a compound of thorium used as a contrast agent (for x-rays) between 1928 and 1955, developed liver and blood diseases.

Thorium is odorless and tasteless and is naturally present in very small quantities almost everywhere on Earth. The average person contains about 100 micrograms of thorium and usually consumes 3 micrograms of thorium each day. After ingestion, thorium is removed from the body by 99.98%. Of the thorium that remains in the body, 75% accumulates in the bones.

How can one determine if one has been exposed to thorium?

We can measure the levels of thorium (not its radioactivity) in blood and most biological materials.

Determination of metals is done by ICP-MS (Inductively Coupled Plasma Mass Spectrometry, Inductively Coupled Argon Plasma Mass Spectrometry), a method that enables the simultaneous detection of many metals. Its sensitivity and accuracy are significantly better than conventional atomic absorption, with the ability to measure metals at concentrations up to 1 in 1015 (1 in 1 quadrillion, ppq)!



Important Note

Laboratory test results are the most important parameter for the diagnosis and monitoring of all pathological conditions. 70%-80% of diagnostic decisions are based on laboratory tests. Correct interpretation of laboratory results allows a doctor to distinguish "healthy" from "diseased".

Laboratory test results should not be interpreted from the numerical result of a single analysis. Test results should be interpreted in relation to each individual case and family history, clinical findings and the results of other laboratory tests and information. Your personal physician should explain the importance of your test results.

At Diagnostiki Athinon we answer any questions you may have about the test you perform in our laboratory and we contact your doctor to get the best possible medical care.

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