Thallium Stress Test: What Is Thallium?
Thallium is a naturally occurring element found in nature. It was first isolated from its ore, which is called thallium sulfate (Sb 2 S 3 ). Its name comes from the Latin word “thalamus”, meaning “earth”. It is a soft white metal with a melting point of -196°C (-302°F). It is chemically similar to lead, but it does not react with water or other liquids.
The most common use of thallium is in batteries. It is used in flashlights and torches because of its low toxicity and high energy density. Other uses include medical devices such as pacemakers, dental fillings, hearing aids, and heart valves. Thallium has been used since ancient times for making silver objects such as rings and coins. It was also used in medicines until the 19th century when it became known that its chemical structure could cause cancer.
It is still being mined today, mostly in China where it is a valuable material for making batteries and catalysts. However, there are concerns about environmental contamination due to poor mining practices and illegal dumping of waste rock into nearby rivers.
Thallium is a heavy metal and can stay in the environment for a long time. It is also known to bioaccumulate. This means that it can build up to toxic levels in humans or animals higher up in the food chain.
Thallium poisoning in humans was first described in 1852 after a British doctor noticed white spots on the skin of a man who had been handling thallium sulfate. This is the most toxic and soluble form of thallium. He died a painful death from internal bleeding, convulsions, and paralysis after only one week. In 1861, a London doctor reported the first case of thallium poisoning in a chemist.
It was also found that thallium could be used to kill rodents such as rats and mice. In fact, it can be used as an effective rat poison. It is odorless and colorless, so a nibbling rodent may be poisoned before it is found.
Thallium acetate (TCA) is slightly less toxic than thallium sulfate. It was once used to kill pests such as rats, but it is no longer allowed in the market due to safety concerns. It was discovered in 1865 by Scottish physician Nathaniel Hodges. He used it to successfully treat an eye infection in a farmer. The farmer’s wife had tried to poison him by putting TCA in his tea, but the dosage was too low to have an effect.
The poison was detected when Hodges tasted the tea and found it to be bitter. He later used thallium acetate to treat other patients, including a woman who had lost her vision after an accident.
Thallium is still used as a pesticide in some parts of the world, particularly in India and China. It is sometimes added to irrigation water or mixed with grain to kill rodents. This practice is banned in the United States and in most developed countries.
Thallium poisoning can occur by inhalation of thallium dust or fumes, by swallowing, injection, or skin contact. Even though it cannot be absorbed through the skin, thallium may cause a rash or irritation. Thallium poisoning symptoms include hair loss, diarrhea and vomiting, insomnia, muscle weakness, lack of energy, and sensory problems. Other signs and symptoms may include slow heart rate, low blood pressure, anemia, and damage to the nervous system.
Since thallium is very similar to potassium, it can interfere with its transport inside cells. This causes potassium levels to drop and induces various effects including heartbeat irregularities and paralysis. If untreated, thallium poisoning is always fatal.
Although there is no known antidote for thallium poisoning, it can be treated if caught in time by removing the thallium source from the body and supplying potassium. Patients may need supportive measures such as a breathing tube or a feeding tube. Removing thallium from the body can be done by forcing the patient to vomit, eliminating bowel movements, and/or administering the drug Prussian Blue.
Thallium was once used in rat poison and known as a woman’s weapon. Some women used it to eliminate their husbands’ mistresses or to kill rival wives. In this case, a little thallium goes a long way and the victim would suffer hair loss, diarrhea, and vomiting. Death occurs when the patient’s heart stops beating.
In 1968, a British woman was found guilty of murdering her husband with thallium. She dissolved thallium chips in water and added it to his tea. He suffered hair loss, nausea, and diarrhea before he died. She was released after her sentence was commuted.
In 1983, a woman from London was found not guilty of murdering her husband by adding thallium to his tea. He had lost most of his hair, had diarrhea and vomiting, and developed a racing heartbeat before he died. The defense claimed that he was a drug addict who may have died from an overdose.
In 1985, a woman from Philadelphia killed her husband by adding thallium to his tea. He suffered from hair loss, diarrhea, and a racing heartbeat before he died. An autopsy revealed that he had ten times the lethal dose of thallium in his body. She was found guilty of first-degree homicide and is currently awaiting her sentencing.
In 2011, a woman from West Sussex pleaded guilty to murdering her boyfriend by putting thallium in his coffee. He had severe stomach pains, lost most of his hair, and suffered from diarrhea before he died.
In September 2013, a woman from Birmingham was sentenced to eight years in jail for poisoning her husband with thallium. She had mixed it into his food to avenge years of alleged abuse. He lost most of his hair, had diarrhea and vomiting, and suffered from a racing heart rate before he died.
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Improved diagnostic accuracy of thallium-201 stress test using multiple observers and criteria derived from interobserver analysis of variance by RD Okada, CA Boucher, HK Kirshenbaum… – The American journal of …, 1980 – Elsevier
Prognostic significance of silent myocardial ischemia on a thallium stress test by LI Heller, M Tresgallo, RR Sciacca, DK Blood… – The American journal of …, 1990 – Elsevier