4. Alongside the two stable isotopes, there are a further 23 radioisotopes, though most of them with fleeting half lives. Thallium in the environment. The element is widely dispersed, mainly in potassium minerals such as sylvite and pollucite. Thallium is a metal element widely used in electronics. It is a soft, heavy, inelastic metal. It’s also suspected as being carcinogenic. In this kind of test, the initial thallium injection is administered while the patient is walking on a treadmill. Thallium is element 81 on the periodic table. Thallium is not a rare element; it is 10 times more abundant than silver. It has the chemical abbreviation Tl and is a soft, grayish metal that resembles tin. A thallium stress test is a nuclear imaging study that shows how well blood flows to the heart muscle. What is Thallium. The chemical symbol for Thallium is Tl.. Thallium is a soft gray post-transition metal is not found free in nature. DESCRIPTION: Thallium was discovered by Sir William Crookes in 1861. The thallium scan is often combined with an exercise test. Thallium is also being tested in high-temperature ceramic superconductors. Small amounts of thallium are used to make certain medical agents and electronics. Thallium, a soft, bluish-gray, malleable heavy metal, was discovered by Sir William Crookes in 1861 while he was making spectroscopic determinations for tellurium on residues from a sulfuric acid plant. Classified as a post-transition metal, Thallium is a solid at room temperature. Thallium is tasteless and odorless and has been used by murderers as a difficult to detect poison. Sources of thallium. It is a soft, heavy, inelastic metal. A further injection is given at another time, when the heart is at rest. These can be readily absorbed through the skin. In some instances, thallium poisoning leads to death. Thallium is readily absorbed through the skin, respiration, and the digestive tract. Commercially, thallium is produced as a byproduct from refining of heavy metal sulfide ores. Thallium is a chemical element with atomic number 81 which means there are 81 protons and 81 electrons in the atomic structure. Thallium contamination of the environment has been reported to be caused by coal-burning power plants, emission from cement factories and water contamination by leaching of thallium from ore processing plants. Thallium is a metal found in small amounts in soil and some minerals. World production of thallium compound is around 30 tonnes per year. Thallium is a potential human carcinogens [4]. Thallium is a chemical element with symbol Tl and atomic number 81. Thallium minerals are rare, but a few are known, such as crookesirte and lorandite. A thallium scan can ensure the heart is receiving enough blood. What is Thallium? In the past, thallium was used in rodent killers and hair removal products. Thallium poisoning foments adverse effects on the nervous system and may cause vomiting, diarrhea, temporary hair loss, and impediments to the lungs, heart, liver, and kidneys. Thallium is a toxic metal and should not come into direct contact with skin. Thallium Poisoning Symptoms. It was once dubbed “Inheritance Powder” due to the ease with which poisoners used it to bump off relatives. Although the metal is reasonably abundant in the Earth's crust at a concentration estimated to be about 0.7 part per million, it exists mostly in association with potassium It usually is combined with an exercise stress test on a treadmill or stationary bicycle. One of them, thallium 201, is useful in nuclear medicine.