Uranium and Thorium

Abstract Uranium is a radioactive metal, the 92nd element in the periodic table, and a member of the actinide series. With the advent of the nuclear age, uranium now occupies a key position in nuclear weapons and energy. Uranium in its depleted form has also been used for military armament and weaponry. Small amounts of uranium are also used in chemicals, ceramics, glass, and photography. Due to uranium's natural radioactivity, both radiological and chemical methods are available for quantitative measurements of uranium in environmental samples and human tissues. Kidney damage has been seen in humans and animals after inhaling or ingesting uranium compounds. Studies in animals have shown that inhalation exposure to insoluble uranium compounds can result in lung damage . Thorium is the 90th element in the periodic table and also a member of the actinide series. Thorium is used as a source of atomic fuel, in the production of incandescent mantles, as an alloying element with magnesium, tungsten, and nickel, and in the past was used as a diagnostic agent for systemic radiological studies. Thorium is primarily a radioactive hazard in humans; but, like uranium, also has chemical toxicity. Breathing high levels of thorium dust results in an increased risk of lung disease. Liver diseases and effects on the blood were found in people injected with thorotrast, a thorium compound injected into the body as a radiographic contrast medium between the years 1928 and 1955.