Thorotrast

High Quality Content by WIKIPEDIA articles! High Quality Content by WIKIPEDIA articles! Thorotrast is a suspension containing particles of the radioactive compound thorium dioxide, ThO2, used as a contrast medium in X-ray diagnostics in the 1930s and 40s (use in some countries, such as the U.S., continued into the 1950s). The naturally abundant thorium nuclide 232Th is slightly unstable and decays through the emission of an alpha particle. Thorium compounds produce excellent images because of thorium's high opacity to X-rays (it has a high cross section for absorption). Because the suspension offered high image quality and had virtually no immediate side-effects compared to the alternatives available at the time, Thorotrast became widely used after its introduction in 1931.