Thorotrast

Thorotrast is a radiocontrast agent that was used in radiography during the mid-20th century. It is a suspension of thorium dioxide particles and was introduced by Anton von Hevesy in 1931. Due to its radioactive properties and the health risks associated with it, the use of Thorotrast was discontinued in the 1950s.

History

Thorotrast was first introduced in 1931 by Anton von Hevesy, a Hungarian radiochemist. It was widely used as a contrast medium in angiography, a medical imaging technique used to visualize the inside of blood vessels. The use of Thorotrast was discontinued in the 1950s when it was discovered that it could cause serious health problems due to its radioactive properties.

Composition

Thorotrast is a suspension of thorium dioxide (ThO2) particles. Thorium dioxide is a radioactive compound that emits alpha particles. The suspension also contains a small amount of thorium-230, which is a decay product of thorium-232.

Use in Radiography

Thorotrast was used as a radiocontrast agent in radiography. It was particularly useful in angiography, as it provided a high degree of contrast between blood vessels and surrounding tissues. However, due to its radioactive properties, the use of Thorotrast was associated with a number of health risks.

Health Risks

The use of Thorotrast has been linked to an increased risk of several types of cancer, including liver cancer, bile duct cancer, and pancreatic cancer. The risk of developing these cancers is believed to be due to the radioactive properties of thorium dioxide and its decay products. In addition, Thorotrast can remain in the body for many years after administration, leading to prolonged exposure to radiation.

Discontinuation

The use of Thorotrast was discontinued in the 1950s when the health risks associated with its use became apparent. Today, safer contrast agents are used in radiography, and the use of Thorotrast is generally considered to be a historical footnote in the field of medical imaging.