what is thallium used for

Thallium is a heavy metal that is used in various industries, including electronics, fiber optics, glass lens, and semiconductor industries. It is also used in the manufacture of electronic components, optical lenses, semiconductor materials, alloys, gamma radiation detection equipment, imitation jewelry, artists paints, low-temperature thermometers, and green fireworks. Trace amounts of thallium are used as a contrast agent in the visualization of cardiac function and tumors. Thallium was also used historically as a rodenticide, but has since been banned in the United States due to its toxicity from accidental exposure. Thallium has been used as a pesticide in other countries, such as in Africa, causing poisoning through contaminated foods. In the past, thallium was used as a therapeutic agent to treat syphilis, gonorrhea, tuberculosis, and ringworm, and it was also used as a depilatory for excess hair. However, due to its toxicity, its use has been limited.