Significance and Uses
- Thallium is widely used in making various electronics, and about 70% of the thallium produced world wide is used in this industry. ...
- Thallium is used in glass industry.
- Thallium is used in pharmaceutical industry to make various drugs and medicines.
- Thallium is used as detectors in infrared devices.
What are the important uses for thallium?
Uses of Thallium. Some of the uses of thallium include: Catalyst during organic reactions. For producing optic laser and related equipment. Radioisotopes and Mercury Lamps. Used in Infra-Red Photocells. It is also beneficial in detecting gamma radiation. It is also used manufacturing glasses.
How is thallium used in everyday life?
Thallium is a bluish-white hued metal found in trace amounts throughout the Earth’s crust. Thallium uses today commonly include the production of electronic devices, fiber optics, camera lenses, switches, and closures. Thallium metal is used most notably by the semiconductor, fiber optic, and the glass lens industries.
Is thallium a metal or nonmetal?
Is thallium a metal or nonmetal? Thallium (Tl), chemical element, metal of main Group 13 (IIIa, or boron group) of the periodic table, poisonous and of limited commercial value. Like lead, thallium is a soft, low-melting element of low tensile strength. Freshly cut thallium has a metallic lustre that dulls to bluish gray upon exposure to air.
Is thallium a metal?
Thallium is a post-transition metal that is not found free in nature. Thallium is primarily used for its electrical conductivity as thallium sulfide, which changes with exposure to infrared light. This ability makes the compound useful in photocells. Thallium bromide-iodide crystals have been used as infrared optical materials.
What is thallium used for in everyday life?
Thallium uses today commonly include the production of electronic devices, fiber optics, camera lenses, switches, and closures. Thallium metal is used most notably by the semiconductor, fiber optic, and the glass lens industries.
What is thallium used for in medicine?
Thallium-201 is a radiopharmaceutical agent used in the diagnosis of coronary artery disease and parathyroid hyperactivity. Other useful applications for a thallium-201 scan, like tumor diagnosis and olfacto-scintigraphy, are being explored and have shown promising results in various studies.
Where is thallium commonly found?
Thallium is found as a mineral in the elements crooksite, lorandite and hutchinsonite. It's also found as a trace element in iron pyrite and obtained from this ore by roasting the mineral. Small amounts of thallium are found in manganese nodules on the ocean floor.
What products have thallium in them?
Thallium is a heavy metal used in the manufacture of electronic components, optical lenses, semiconductor materials, alloys, gamma radiation detection equipment, imitation jewelry, artist's paints, low temperature thermometers, and green fireworks.
What foods contain thallium?
The four vegetables with the highest thallium levels (watercress, radish, turnip and green cabbage) were all Brassicaceous plants, followed by the Chenopods beet and spinach. At a thallium concentration of 0.7 mg/kg in the soil only green bean, tomato, onion, pea and lettuce would be safe for human consumption.
How can you tell if someone is slowly poisoned?
feeling agitated. low blood pressure, which can cause symptoms such as lightheadedness and fainting. chest pain. a slow heartbeat (below 60 beats per minute)
Is thallium toxic to humans?
Thallium is considered a cumulative poison that can cause adverse health effects and degenerative changes in many organs. The effects are the most severe in the nervous system.
How can I get thallium?
Thallium is mainly obtained as a by-product from the smelting of copper, zinc and lead ores. Its main entry into the environment is from coal-burning and smelting where it stays in the air, water and soil for a long time.
What does thallium do to the brain?
Thallium intoxication can severely affect the nervous system, including peripheral (sensorimotor neuropathy), central (altered mental status, convulsions, and extrapyramidal and cerebellar dysfunctions), and autonomic (tachycardia, hypertension, and urinary retention) neural systems.
Does the human body use thallium?
It does not have a known biological use and does not appear to be an essential element for life. It has been considered one of the most toxic heavy metals. Occasionally, there are reports on thallium poisoning as results of suicide or murder attempt or accident.
When was thallium banned?
The odorless and tasteless thallium sulfate was also used as rat poison and ant killer. Since 1975, this use in the United States and many other countries is prohibited due to safety concerns.
What is Thallium?
Thallium is element 81 on the periodic table. It has the chemical abbreviation Tl and is a soft, grayish metal that resembles tin. Thallium isn't found freely in nature, and it has kind of a bad reputation as a toxic element. In fact, it's often referred to as 'the poisoner's poison' because it's often difficult to trace in the body and is often discovered too late to save someone who's been poisoned with it. Historically, thallium has been used in rat poison and insecticides.
What is the most important thing to remember about thallium?
Although thallium has a lot of uses, as discussed above, one of the most important things to remember about this element is its toxicity . Let's say you are exposed to high levels of thallium -- how will you know? What treatments are available? Will you die right away? These are some of the questions that might come to mind when thinking about the hazardous nature of the element.
How long does it take for thallium to kill you?
To answer these questions, and to explore more facts of thallium, you can usually tell if you have been affected by the element within 1 to 5 days. If left untreated, high levels of thallium exposure can cause death in about eight days. The effects of thallium poisoning cannot be reversed. Thallium is also so toxic that it can be easily absorbed through the skin. Therefore, one must use extreme caution when dealing with thallium.
Where can thallium be found?
It can be found in small amounts in glass, electronics, and optics , and we even consume very tiny amounts each day. Although the effects of thallium exposure are irreversible, if caught in the first few days of exposure, thallium poisoning can be treated.
Is thallium a solid?
Like most other metals in the periodic table, thallium has a high relative melting point and a high boiling point. It is a soft, solid material at room temperature and possesses a high density. Thallium is so soft that it can be cut with a knife at room temperature. Therefore, it is highly malleable and can easily be shaped. Its appearance is highly lustrous, and thallium can easily be oxidized upon exposure to air. That means that thallium can easily form an oxide layer on its surface unless it is preserved in oil.
What is thallium used for?
One of the most important and relatively newer uses of thallium involves diagnostic testing procedures requiring trace materials for labeling purposes—specifically, this element has gained wide acceptance in the field of myocardial perfusion imagery (MPI) in some countries.
Why is thallium important?
Some sources report that thallium in this century does play an important role in certain types of commercial mining procedures. For example, in some countries, mining firms use thallium to assist with separating gemstones from ores. It is sometimes a byproduct following the smelting of certain metals also.
What group is thallium in?
The element holds an atomic number of 81, and it is classified within Group 13 in the Periodic Table.
What industries use thallium?
Today, thallium compounds do play a role in certain industries, including: electronic parts manufacturing, mining, medical diagnostic testing, optics and the pesticide manufacturing. These uses have caused some companies to sell thallium commercially in some parts of the world.
Where does thallium come from?
Somewhat similar to lead in appearance, thallium occurs naturally in trace amounts in the Earth’s crust. It develops a metallic blue-gray sheen upon exposure to air. For many years, people produced thallium mainly as an industrial byproduct.
Is thallium radioactive?
Cardiologists seeking to examine blood flow in arteries of the heart have found that radioactive thallium compounds in trace quantities may greatly assist certain diagnostic procedures. This application, of course, did not become widespread until comparatively recently.
Is thallium a metal?
Some industries in this century employ compounds of thallium, a toxic metallic element, for a variety of commercial purposes. However, certain properties of this substance probably restrict its overall usefulness in the marketplace. Thallium often figures amongst the harmful materials which must be removed from environmentally contaminated sites.
What is thallium used for?
Thallium (I) bromide and thallium (I) iodide crystals have been used as infrared optical materials, because they are harder than other common infrared optics, and because they have transmission at significantly longer wavelengths. The trade name KRS-5 refers to this material. Thallium (I) oxide has been used to manufacture glasses that have a high index of refraction. Combined with sulfur or selenium and arsenic, thallium has been used in the production of high- density glasses that have low melting points in the range of 125 and 150 °C. These glasses have room temperature properties that are similar to ordinary glasses and are durable, insoluble in water and have unique refractive indices.
What are the minerals that make up thallium?
In addition, several other thallium minerals, containing 16% to 60% thallium, occur in nature as complexes of sulfides or selenides that primarily contain antimony, arsenic, copper, lead, and/or silver. These minerals are rare, and they have had no commercial importance as sources of thallium.
How is thallium leached?
The thallium is leached either by the use of a base or sulfuric acid from the material. The thallium is precipitated several times from the solution to remove impurities. At the end it is converted to thallium sulfate and the thallium is extracted by electrolysis on platinum or stainless steel plates.
What is the most stable isotope of thallium?
Thallium has 41 isotopes which have atomic masses that range from 176 to 216. 203 Tl and 205 Tl are the only stable isotopes and make up nearly all of natural thallium. 204 Tl is the most stable radioisotope, with a half-life of 3.78 years. It is made by the neutron activation of stable thallium in a nuclear reactor. The most useful radioisotope, 201 Tl (half-life 73 hours), decays by electron capture, emitting X-rays (~70–80 keV), and photons of 135 and 167 keV in 10% total abundance; therefore, it has good imaging characteristics without excessive patient radiation dose. It is the most popular isotope used for thallium nuclear cardiac stress tests.
Why do you add thallium salts to gold plating?
Soluble thallium salts are added to gold plating baths to increase the speed of plating and to reduce grain size within the gold layer. A saturated solution of equal parts of thallium (I) formate (Tl (CHO 2 )) and thallium (I) malonate (Tl (C 3 H 3 O 4 )) in water is known as Clerici solution.
How many electrons does thallium have?
A thallium atom has 81 electrons, arranged in the electron configuration [Xe]4f 14 5d 10 6s 2 6p 1; of these, the three outermost electrons in the sixth shell are valence electrons. Due to the inert pair effect, the 6s electron pair is relativistically stabilised and it is more difficult to get them involved in chemical bonding than for the heavier elements. Thus, very few electrons are available for metallic bonding, similar to the neighboring elements mercury and lead, and hence thallium, like its congeners, is a soft, highly electrically conducting metal with a low melting point of 304 °C.
What is the atomic number of thallium?
Thallium is a chemical element with the symbol Tl and atomic number 81 . It is a gray post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. Chemists William Crookes and Claude-Auguste Lamy discovered thallium independently in 1861, in residues of sulfuric acid production.
What is thallium used for?
Small amounts of thallium are used to make certain medical agents and electronics. In the past, thallium was used in rodent killers and hair removal products.
How does thallium affect people?
How Thallium Affects People’s Health. The human health effects from exposure to low environmental levels of thallium are unknown. Hair loss and nerve damage have occurred after a person has consumed large amounts of thallium. Other effects of consuming unusually large amounts of thallium include nausea and vomiting followed by the failure ...
Is thallium in urine?
CDC scientists found measurable levels of thallium in the urine in most participants, indicating widespread exposure. The 2003–2004 levels were similar to those in previous survey periods of the Fourth Report.
Does thallium cause health problems?
Finding measurable amounts of thallium in urin e does not imply that the levels of thallium cause an adverse health effect . Biomonitoring studies on levels of thallium provide physicians and public health officials with reference values so that they can determine whether people have been exposed to higher levels of thallium than are found in the general population. Biomonitoring data can also help scientists plan and conduct research on exposure and health effects.
What is thallium found in?
Thallium is an abundant element and is present in about 0.7 mg/kg of the Earth’s crust. Thallium does not exist in free elemental form in nature. it mostly exists in the form of ores with other elements, mostly potassium. Commercially, thallium is extracted from its sulfide-ores of heavy metals, such as zinc, lead, copper etc., which contain 16% to 60 of thallium. The mineral crookesite, lorandite (TlAsS 2) and hutchinsonite (TlPbAs 5 S 9) are common minerals of thallium. It is also found in ocean beds in combination with manganese nodules. Annually, about 10 metric tons of thallium is produced worldwide as a byproduct during the smelting of lead, zinc and copper ores [2]. Large deposits of thallium are found in southern Macedonia where active mining of thallium is carried out.
How many isotopes are there in thallium?
There are twenty-five isotopes of thallium. Their atomic masses range from 184 to 210. Naturally occurring thallium have two stable isotopes, thalium-203 and thalium-205. These two isotopes make all naturally occurring thallium. Among the radioactive isotopes, thallium-204 is the most stable isotope and have a half-life of 3.78 years [5].
When was thalassium discovered?
Thallium was discovered independently in 1986 by William Crookes and Claude-Auguste Lamy. Due to its toxic nature, it has been historically used as ant killer and rat poison.
Is thallium a strong oxidizing agent?
Thallium exists in two oxidation states, +3 and +1. Thallium compounds with +3 oxidation state are strong oxidizing agents. They are relatively unstable. Thallium reacts with halogens and thallium halides are stable in nature. thallium reacts with water to form thallium hydroxide. It dissolves in nitric acid and sulfuric acid and forms salts of nitrate and sulphate [3].
Is thallium a metal?
Thallium is a greyish color post-transition metal. It is soft and can be cut with a knife. Thallium is malleable. Freshly isolated thallium looks like tin and is readily discolored (becomes bluish-grey) and loses it shine when exposed to air. It is quite dense and have a density of 11.85 g/cm 3. Thallium has a high boiling point, 1473 ° C and a melting point of 304 °C.
When was Darmstadtium synthesized?
Darmstadtium is an artificial element that was synthesized in 1994. It is highly radioactive and…
Is thallium a toxic substance?
Certain compounds of thallium are highly toxic. They have been used as insecticides and rat poison. However, due to the dangers of their non-selective poisoning, the use of thallium-based poisons has been banned in various countries. Thallium compounds are highly soluble in water that increases their risk of toxicity. 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. These can be readily absorbed through the skin. Thallium is a potential human carcinogens [4].
What are the characteristics of thalium?
DESCRIPTION: Thallium was discovered by Sir William Crookes in 1861. It is a soft, heavy, inelastic metal. Thallium is tasteless and odorless and has been used by murderers as a difficult to detect poison.
Why can't thalium be used in water?
Water: Thallium cannot be used to contaminate water because it does not dissolve in water.
How long does it take for thallium to cause alopecia?
This is followed by a neurological phase 2 to 5 days or more after ingestion, although it may occur as early as 12 hours after massive ingestion. In acute toxicity, alopecia may occur 2 to 3 weeks after exposure . Death may occur in severe cases 5 to 7 days following exposure due to respiratory paralysis and failure.
What is the purpose of decontamination?
INTRODUCTION: The purpose of decontamination is to make an individual and/or their equipment safe by physically removing toxic substances quickly and effectively . Care should be taken during decontamination, because absorbed agent can be released from clothing and skin as a gas. Your Incident Commander will provide you with decontaminants specific for the agent released or the agent believed to have been released.
Is thalium a rodenticide?
It also has use in some chemical reactions and medical procedures. Thallium was used historically as a rodenticide, but has since been banned in the United States due to its toxicity from accidental exposure. METHODS OF DISSEMINATION : Indoor Air: Thallium can be released into indoor air as fine particles (aerosol).
Can thallium be released into the air?
Agricultural: If thallium is released into the air as fine particles (aerosol), it has the potential to contaminate agricultural products.
What is thallium?
Pure thallium is a bluish-white metal that is found in trace amounts in the earth's crust. In the past, thallium was obtained as a by-product from smelting other metals; however, it has not been produced in the United States since 1984. Currently, all the thallium is obtained from imports and from thallium reserves.
What is thalassium used for?
Thallium is used mostly in manufacturing electronic devices, switches, and closures, primarily for the semiconductor industry. It also has limited use in the manufacture of special glass and for certain medical procedures.
What happens to thallium when it enters the environment?
Thallium enters the environment primarily from coal-burning and smelting, in which it is a trace contaminant of the raw materials. It stays in the air, water, and soil for a long time and is not broken down. Some thallium compounds are removed from the atmosphere in rain and snow. It's absorbed by plants and enters the food chain. It builds up in fish and shellfish.
How likely is thallium to cause cancer?
The Department of Health and Human Services, the International Agency for Research on Cancer, and the Environmental Protection Agency (EPA) have not classified thallium as to its human carcinogenicity.
What is thallium odorless?
In its pure form, thallium is odorless and tasteless. It can also be found combined with other substances such as bromine, chlorine, fluorine, and iodine. When it's combined, it appears colorless-to-white or yellow.
What element was used in the 2007 poisoning of a woman?
Medical Editor: William C. Shiel Jr., MD, FACP, FACR. The March 2007 poisoning of an American woman and her daughter in Russia with the element thalliumsparked widespread media attention. After the women became ill in Moscow, they returned to the U.S. for treatment, where the diagnosis of thallium poisoning was confirmed.
How much thallium should be discharged?
The EPA requires that discharges or accidental spills into the environment of 1,000 pounds or more of thallium be reported.
Why do doctors order thallium tests?
Your doctor may order a thallium test for a variety of reasons, including: if they suspect your heart isn’t getting enough blood flow when it’s under stress — for example, when you exercise.
What is a thallium stress test?
A thallium stress test is a nuclear imaging test that shows how well blood flows into your heart while you’re exercising or at rest. This test is also called a cardiac or nuclear stress test. During the procedure, a liquid with a small amount of radioactivity called a radioisotope is administered into one of your veins.
What is the radioactive material on a heart test?
The radioactive material marks your blood flow and is picked up by the gamma camera. The test includes an exercise and resting portion, and your heart is photographed during both. The doctor administering your test will determine the order that these tests are performed in.
Where to do a thallium test?
The test must be done at a hospital, medical center, or doctor’s office. A nurse or healthcare professional inserts an intravenous (IV) line, usually on the inside of your elbow. A radioisotope or radiopharmaceutical medication, such as thallium or sestamibi, is injected through the IV.
Can you feel a sting from a thallium stress test?
Most people tolerate the thallium stress test very well. You may feel a sting as the medication that simulates exercise is injected, followed by a warm feeling. Some people may experience headache, nausea, and a racing heart. The radioactive material will leave your body through your urine.
What does a thallium stress test mean?
What Do Your Thallium Stress Test Results Mean? The thallium stress test is an imaging study that shows your doctor how well blood flows to your heart. It measures your blood flow during rest and after exercise. The thallium stress test is also called a nuclear stress test, a treadmill test, a stress perfusion test, or a cardiac SPECT.
What does it mean when there is no thallium in your heart?
No thallium visible in parts of the heart. If there is no radioactive dye visible in a certain part of your heart, this is a sign of damage from a heart attack. Share on Facebook Share on Twitter Share on Pinterest Email Print. Pagination.
What Are the Risks of Thallium Stress Test?
The thallium stress test is a very safe procedure, and you’re closely monitored the whole time. But it may have some risks, including:
How long does it take to do a thallium stress test?
The thallium stress test has two parts: at rest and while exercising. It takes about 4 hours to do both parts of the test. Thallium stress tests are done in a hospital, an imaging center, or a cardiologist’s clinic. Follow your doctor’s instructions to prepare.
Overview
Thallium is a chemical element with the symbol Tl and atomic number 81. It is a gray post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. Chemists William Crookes and Claude-Auguste Lamy discovered thallium independently in 1861, in residues of sulfuric acid production. Both used the newly developed method of flame spect…
Characteristics
A thallium atom has 81 electrons, arranged in the electron configuration [Xe]4f 5d 6s 6p ; of these, the three outermost electrons in the sixth shell are valence electrons. Due to the inert pair effect, the 6s electron pair is relativistically stabilised and it is more difficult to get these involved in chemical bonding than it is for the heavier elements. Thus, very few electrons are available for metallic bonding, similar to the neighboring elements mercury and lead. Thallium, then, like its co…
Compounds
Thallium(III) compounds resemble the corresponding aluminium(III) compounds. They are moderately strong oxidizing agents and are usually unstable, as illustrated by the positive reduction potential for the Tl /Tl couple. Some mixed-valence compounds are also known, such as Tl4O3 and TlCl2, which contain both thallium(I) and thallium(III). Thallium(III) oxide, Tl2O3, is a black solid which decomposes above 800 °C, forming the thallium(I) oxide and oxygen.
History
Thallium (Greek θαλλός, thallos, meaning "a green shoot or twig") was discovered by William Crookes and Claude Auguste Lamy, working independently, both using flame spectroscopy (Crookes was first to publish his findings, on March 30, 1861). The name comes from thallium's bright green spectral emission lines.
After the publication of the improved method of flame spectroscopy by Robert Bunsen and Gusta…
Occurrence and production
Although thallium is a modestly abundant element in the Earth's crust, with a concentration estimated to be 0.7 mg/kg, mostly in association with potassium-based minerals in clays, soils, and granites, thallium is not generally economically recoverable from these sources. The major source of thallium for practical purposes is the trace amount that is found in copper, lead, zinc, and other heav…
Applications
The odorless and tasteless thallium sulfate was once widely used as rat poison and ant killer. Since 1972 this use has been prohibited in the United States due to safety concerns. Many other countries followed this example. Thallium salts were used in the treatment of ringworm, other skin infections and to reduce the night sweating of tuberculosis patients. This use has been limited due to their n…
Toxicity
Thallium and its compounds are extremely toxic, with numerous recorded cases of fatal thallium poisoning. The Occupational Safety and Health Administration (OSHA) has set the legal limit (permissible exposure limit) for thallium exposure in the workplace as 0.1 mg/m skin exposure over an eight-hour workday. The National Institute for Occupational Safety and Health (NIOSH) also set a recommended exposure limit (REL) of 0.1 mg/m skin exposure over an eight-hour work…
See also
• Chemistry portal
• Myocardial perfusion imaging
How People Are Exposed to Thallium
- People may be exposed to thallium from coal-burning and smelting processes that produce fine particles of the metal. The tiny particles can be inhaled from the air or consumed in food or drink.
How Thallium Affects People’s Health
- The human health effects from exposure to low environmental levels of thallium are unknown. Hair loss and nerve damage have occurred after a person has consumed large amounts of thallium. Other effects of consuming unusually large amounts of thallium include nausea and vomiting followed by the failure of multiple body organs, brain injury, and deat...
Levels of Thallium in The U.S. Population
- In the Fourth National Report on Human Exposure to Environmental Chemicals (Fourth Report), CDC scientists measured thallium in the urine of 2,558 participants aged six years and older who took part in the National Health and Nutrition Examination Survey (NHANES) during 2003–2004. Prior survey periods of 1999–2000 and 2001–2002 are also included in the Fourth Report. By m…
Additional Resources
- Agency for Toxic Substances and Disease Registry
1. Public Health Statement for Thallium - Environmental Protection Agency
1. Consumer Factsheet on: Thalliumpdf iconexternal icon