| Identification | More | [Name]
THALLIUM | [CAS]
7440-28-0 | [Synonyms]
Ramor
TALLIUM
TL007921
TL007915
THALLIUM
Aids072434
Aids-072434
rod,99.999%
Thallium, rod
THALLIUM, LUMP
THALLIUM METAL
THALLIUM 99.9%
Thallium element
Thallium (L) ion
Thallium granules
thallium metallic
THALLIUM STANDARD
thallium,elemental
Tl Standard Solution
Thallium, lump, 99+%
THALLIUM ICP STANDARD
Thallium, rod, 99.999%
Thalliumgranules(99.9%)
THALLIUM, INGOT, 99.99%
Thallium powder, 99.999%
RINGERS SOLUTION 20X10ML
Thalliumgranules(99.999%)
THALLIUM STANDARD SOLUTION
Thallium, soluble compounds
Thallium standard for AAS
Thallium standard for ICP
THALLIUM, SHOT, - 6MM, 99.9%
Thallium(I) nitrate solution
THALLIUM, AAS STANDARD SOLUTION
THALLIUM SINGLE ELEMENT STANDARD
THALLIUM METALLO-ORGANIC STANDARD
THALLIUM PLASMA EMISSION STANDARD
THALLIUM, PLASMA STANDARD SOLUTION
THALLIUM, GRANULATED (UNDER WATER)
Thallium rod, 12.7mm (0.5 in.) dia.
THALLIUM AA SINGLE ELEMENT STANDARD
THALLIUM ATOMIC ABSORPTION STANDARD
THALLIUM ATOMIC SPECTROSCOPY STANDARD
THALLIUM SINGLE ELEMENT PLASMA STANDARD
THALLIUM, ORGANIC AAS STANDARD SOLUTION
Thallium, Rod 1.27Cm Dia. X 15Cm Long, 225G
THALLIUM ATOMIC ABSORPTION STANDARD SOLUTION
Thallium, AAS standard solution, Tl 1000μg/mL
Thallium, granules, 1-5mm, 99.9+% metals basis
THALLIUM PLASMA EMISSION SPECTROSCOPY STANDARD
Thallium plasma standard solution, Tl 1000μg/mL
Thallium plasma standard solution, Tl 10000μg/mL
Thallium granules, ≤6mm, 99.99% trace metals basis
THALLIUM, ROD, 8 MM DIAM. X 50 MM LENGTH , 99.999%
THALLIUM ATOMIC ABSORPTION SINGLE ELEMENT STANDARD
Thallium, Rod 1.27Cm Dia. X 15Cm Long, 225G 99.999%
Thallium, rod, 1.27 cm dia x 15 cm long, 225 gm/rod
Thallium rod, 12.7mm dia., 99.99% trace metals basis
Thallium rod, 12.7mm (0.5in) dia, 99.9% (metals basis)
Thallium rod, 12.7mm (0.5in) dia, 99.99% (metals basis)
Thallium rod, 12.7mm (0.5in) dia, 99.999% (metals basis)
Thallium, AAS standard solution, Specpure(R), Tl 1000μg/ml
ThalliuM granules, 6MM (0.2in) & down, 99.99% (Metals basis)
ThalliuM granular, 1-5 MM diaMeter, 99.99% trace Metals basis
Thallium granules, 6mm (0.2in) & down, 99.999% (metals basis)
Thallium, plasma standard solution, Specpure(R), Tl 1000μg/ml
Thallium, plasma standard solution, Specpure(R), Tl 10,000μg/ml
Thallium, Organic AAS standard solution, Specpure|r, Tl 1000^mg/g | [EINECS(EC#)]
231-138-1 | [Molecular Formula]
Tl | [MDL Number]
MFCD00134063 | [Molecular Weight]
204.38 | [MOL File]
7440-28-0.mol |
| Chemical Properties | Back Directory | [Appearance]
Thallium is a soft, bluish-white, heavy, very soft metal insoluble in water and organic solvents. It turns gray on exposure to air. | [Melting point ]
303 °C(lit.)
| [Boiling point ]
1457 °C(lit.)
| [density ]
1.01 g/mL at 25 °C
| [solubility ]
insoluble in H2O; reacts with acid solutions | [form ]
rod
| [color ]
Clear colorless | [Specific Gravity]
11.85 | [Stability:]
Stable. | [Resistivity]
18 μΩ-cm, 20°C | [Water Solubility ]
insoluble H2O; reacts with HNO3, H2SO4 [MER06] | [Merck ]
13,9327 | [Exposure limits]
TLV-TWA 0.1 mg/m3 (thallium and its soluble
salts) (ACGIH, MSHA, and OSHA);
IDHL 10/mg/m3. | [History]
Thallium was discovered spectroscopically
in 1861 by Crookes. The element was named after the
beautiful green spectral line, which identified the element.
The metal was isolated both by Crookes and Lamy in 1862
about the same time. Thallium occurs in crooksite, lorandite,
and hutchinsonite. It is also present in pyrites and is recovered
from the roasting of this ore in connection with the production
of sulfuric acid. It is also obtained from the smelting
of lead and zinc ores. Extraction is somewhat complex and
depends on the source of the thallium. Manganese nodules,
found on the ocean floor, contain thallium. When freshly
exposed to air, thallium exhibits a metallic luster, but soon
develops a bluish-gray tinge, resembling lead in appearance.
A heavy oxide builds up on thallium if left in air, and in the
presence of water the hydroxide is formed. The metal is very
soft and malleable. It can be cut with a knife. Forty-seven isotopes
of thallium, with atomic masses ranging from 179 to 210
are recognized. Natural thallium is a mixture of two isotopes.
The element and its compounds are toxic and should be handled
carefully. Contact of the metal with skin is dangerous,
and when melting the metal adequate ventilation should be
provided. Thallium is suspected of carcinogenic potential for
man. Thallium sulfate has been widely employed as a rodenticide
and ant killer. It is odorless and tasteless, giving no warning
of its presence. Its use, however, has been prohibited in
the U.S. since 1975 as a household insecticide and rodenticide.
The electrical conductivity of thallium sulfide changes with
exposure to infrared light, and this compound is used in photocells.
Thallium bromide-iodide crystals have been used as infrared
optical materials. Thallium has been used, with sulfur
or selenium and arsenic, to produce low melting glasses which
become fluid between 125 and 150°C. These glasses have
properties at room temperatures similar to ordinary glasses
and are said to be durable and insoluble in water. Thallium
oxide has been used to produce glasses with a high index of
refraction. Thallium has been used in treating ringworm and
other skin infections; however, its use has been limited because
of the narrow margin between toxicity and therapeutic
benefits. A mercury–thallium alloy, which forms a eutectic at
8.5% thallium, is reported to freeze at –60°C, some 20° below
the freezing point of mercury. Thallium metal (99.999%) costs
about $2/g. | [CAS DataBase Reference]
7440-28-0(CAS DataBase Reference) | [EPA Substance Registry System]
Thallium (7440-28-0) |
| Hazard Information | Back Directory | [Chemical Properties]
silver-grey metal, tarnishing quickly in air | [Chemical Properties]
Thallium is a soft, bluish-white, heavy, very soft metal insoluble in water and organic solvents. It turns gray on exposure to air. | [Definition]
ChEBI: A metallic element first identified and named from the brilliant green line in its flame spectrum (from Greek thetaalphalambdalambdaomicronsigma, a green shoot). | [Uses]
In semi-conductor industry; alloyed with mercury for switches and closures which operate at subzero temperetures. In manufacture of highly refractive optical glass. Has been used in admixture with 97-98% of inert substances as poison for rats and other rodents. | [General Description]
Bluish-white soft malleable metal or gray granules. Density 11.85 g/cm3. Emits toxic fumes when heated. May be packaged under water. | [Hazard]
Forms toxic compounds on contact with
moisture; keep from skin contact. Gastrointestinal
damage and peripheral neuropathy. | [Reactivity Profile]
THALLIUM(7440-28-0) is a reducing agent. Reacts so vigorously with fluorine that the metal becomes incandescent [Mellor 5:421 1946-47]. | [Air & Water Reactions]
Flammable in the form of powder or dust. Insoluble in water. | [Potential Exposure]
Thallium is usually obtained as a byproduct from the flue dust generated during the roasting of pyrite ores in the smelting and refining of lead and zinc. Thallium has not been produced in the United States since 1984, but is imported for use in the manufacture of electronics, optical lenses, and imitation precious jewels. It also has use in some chemical reactions and medical procedures. Thallium and its compounds are used as a rodenticide and fungicide; in the manufacture of plates and prisms, high-density liquids; as insecticides, catalysts; in certain organic reactions, in phosphor activators; in bromoiodide crystals for lenses, plates, and prisms in infrared optical instruments; in photoelectric cells; in mineralogical analysis; alloyed with mercury in low-temperature thermometers, switches and closures; in high-density liquids; in dyes and pigments; in fire-works; and imitation precious jewelry. It forms a stainless alloy with silver and a corrosion-resistant alloy with lead. Its medicinal use for epilation has been almost discontinued. Highly persistent in the environment. Note: Thallium was used in the past as a rodenticide, it has been banned in the United States due to its toxicity from accidental exposure. In some countries, thallium(I)sulfate(2:1) is still used as a rat poison and ant bait. | [First aid]
Move victim to fresh air. Call 911 or emergency medical service. Give artificial respiration if victim is not breathing. Do not use mouth-to-mouth method if victim ingested or in haled the substance; give artificial respiration with the aid of a pocket mask equipped with a one-way valve or other proper respiratory medical device. Administer oxygen if breathing is difficult. Skin : If this chemical contacts the skin, remove contaminated clothing and immediately flush skin or eyes with running water for at least 20 minutes. For minor skin contact, avoid spreading material on unaffected skin. Keep victim warm and quiet. Effects of exposure to substance may be delayed. The symptoms of acute thallium poisoning (except for gastrointestinal symptoms) may not become manifest until 12 hours to 4 days after exposure. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Medical observation is also recommended for at least 24 to 48 hours after breathing overexposure as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or otherinhalation therapy. Cigarette smoking may exacerbate pulmonary injury and should be discouraged for at least 72 hours following exposure. Eyes: If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. Inhalation: If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. Ingestion: Get medical attention. If patient is conscious, give a slurry of activated charcoal in water to drink and induce vomiting. Do not make an unconscious person vomit. Note for qualified medical personnel: For severe poisoning consider BAL (British Anti-Lewisite), dimercaprol, dithiopropanol (C3H8OS2) which has been used to treat toxic symptoms of certain heavy metals poisoning. In the case of thallium it may have some value. Although BAL is reported to have a large margin of safety, caution must be exercised, because toxic effects may be caused by excessive dosage. Most can be prevented by premedication with 1-ephedrine sulfate (CAS: 134-72-5). | [Shipping]
Thallium: UN3288 Toxic solids, inorganic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. UN1707 Thallium compounds, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. | [Incompatibilities]
Varies. Cold thallium ignites on contact with fluorine. Thallium metal reacts violently with strong acids (such as hydrochloric, sulfuric, and nitric) and strong oxidizers (such as chlorine, bromine, and fluorine). Cold thallium ignites on contact with fluorine. Reacts with other halogens at room temperature. | [Description]
Thallium was discovered in 1861 by Sir William Crookes (and
independently by Claude-Auguste Lamy a year later) and
occurs in the lithosphere at 0.7 ppm. The name thallium is in
reference to the particularly bright green spectral lines seen in
the spectra resultant from a flame spectroscopy test (from
Greek thallos, meaning a green shoot or twig), the one used in
its discovery. Thallium is a heavy metallic element that exists in
the environment mainly combined with other elements
(primarily oxygen, sulfur, and the halogens) in inorganic
compounds. | [Waste Disposal]
Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal. Dilute thallium solutions may be disposed of in chemical waste landfills. When possible, thallium should be recovered and returned to the suppliers. | [Isotopes]
There are a total of 55 isotopes for thallium. All are radioactive with relativelyshort half-lives, and only two are stable. The stable ones are Tl-203, which constitutes29.524% of the element’s existence in the Earth’s crust, and Tl-205, which makes up70.476% of the element’s natural abundance found in the Earth’s crust. | [Origin of Name]
From the Greek word thallos, meaning “young shoot” or “green twig.”
Named for the green spectral line produced by the light from the element in a spectroscope. | [Occurrence]
Thallium is the 59th most abundant element found in the Earth’s crust. It is widely distributedover the Earth, but in very low concentrations. It is found in the mineral/ores ofcrooksite (a copper ore; CuThSe), lorandite (TlAsS2), and hutchinsonite (lead ore, PbTl). Itis found mainly in the ores of copper, iron, sulfides, and selenium, but not in its elementalmetallic state. Significant amounts of thallium are recovered from the flue dust of industrialsmokestacks where zinc and lead ores are smelted. | [Characteristics]
Elemental thallium metal is rare in nature mainly because it oxidizes if exposed to air (oxygen)and water vapor, forming thallium oxide, a black powder. Although some compounds ofthallium are both toxic and carcinogenic, they have some uses in the field of medicine. Somecompounds have the ability to alter their electrical conductivity when exposed to infraredlight. | [Production Methods]
Thallium sulfide is insoluble in alkaline solution, but soluble in acid,
allowing its separation from group I elements. Thallium
chloride is only slightly soluble in cold water, which permits
its separation from chlorides of cadmium, copper, tellurium,
and zinc.
Thallium metal may be obtained from the compounds in
several ways: by electrolysis of carbonates, sulfates, or
perchlorates; by precipitation of metallic thallium with
zinc; and by reduction of thallous oxalate or chloride. A
number of industrial processes for the recovery of thallium
have been described in the literature. Several of them depend
on the extraction of thallium from flue dust by boiling it in
acidified water. | [Health Hazard]
Thallium and its soluble compounds arehighly toxic in experimental animals. Theacute toxic symptoms in humans are nausea,vomiting, diarrhea, polyneuritis, convulsion,and coma. Ingestion of 0.5 g can be fatalto humans. Severe chronic toxicity can leadto kidney and liver damage, deafness, andloss of vision. Other signs of toxicity fromchronic exposure include reddening of theskin, abdominal pain, polyneuritis, loss ofhair, pain in legs, and occasionally cataracts.Ingestion of thallium salts in children hascaused neurological abnormalities, mentalretardation, and psychoses.
Hoffman (2000) reviewed thallium poisoningin women during pregnancy and cited acase that began in the first trimester of pregnancyresulting in fetal demise. John Peter andViraraghavan (2005) have reviewed toxicityof thallium and public health risk and discussedenvironmental concerns and variousremoval technologies from aquatic system.
. | [Carcinogenicity]
Female mice treated orally or
cutaneously with high doses of thallium showed a degenerative
process in the genital tract similar to that found in
castrated animals or after uterine denervation. The diagnoses
were papilloma, precancerous lesions, and cancer. The control
mice did not develop cancer. | [Environmental Fate]
Metallic thallium (TI) is bluish white or gray; it is very soft
and malleable. The element can exist in the environment
mainly combined with other elements (primarily oxygen,
sulfur, and the halogens) in inorganic compounds. Thallium
exists in monovalent (thallous, thallium (I), Tl+1) and
trivalent (thallic, thallium (III), Tl+3) states. Monovalent
thallium ions also are more stable in aqueous solution, but
trivalent thallium (Tl+3) can be stabilized by complexing
agents. Monovalent thallium is similar to potassium (K+) in
ionic radius and electrical charge, which contribute to its
toxic nature.
Compounds of thallium, however, are generally soluble in
water and the element is found primarily as the monovalent
ion (Tl+). Thallium tends to adsorb to soils and sediments,
and to bioconcentrate in aquatic plants, invertebrates, and
fish. Terrestrial plants can also absorb thallium from soil. Thallium is quite stable in the environment because it is
neither transformed nor biodegraded. However, thallium may
be bioconcentrated by organisms from water. The US Environmental
Protection Agency has identified several National
Priorities List sites polluted by thallium. | [Toxicity evaluation]
Several mechanisms have been postulated for the toxic action
of thallium; however, the exact mechanism or mechanisms of
toxicity are unknown. Thallium’s mechanism of toxicity is
related to its ability to interfere with potassium ion functions
because both obtain similar ionic radii. In addition, there is
evidence that thallium interferes with energy production at
essential steps in glycolysis, the Kreb’s cycle, and oxidative
phosphorylation that adversely affects protein synthesis. Other
effects include inhibition of sodium–potassium–adenosine
triphosphatase and binding to sulfhydryl groups. |
| Safety Data | Back Directory | [Hazard Codes ]
Xn,T+ | [Risk Statements ]
R26/28:Very Toxic by inhalation and if swallowed .
R33:Danger of cumulative effects.
R53:May cause long-term adverse effects in the aquatic environment.
R36/37/38:Irritating to eyes, respiratory system and skin .
R20/22:Harmful by inhalation and if swallowed .
R36/38:Irritating to eyes and skin . | [Safety Statements ]
S13:Keep away from food, drink and animal feeding stuffs .
S28:After contact with skin, wash immediately with plenty of ... (to be specified by the manufacturer) .
S45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) .
S61:Avoid release to the environment. Refer to special instructions safety data sheet .
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection .
S36/37:Wear suitable protective clothing and gloves .
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice . | [RIDADR ]
UN 3288 6.1/PG 2
| [WGK Germany ]
3
| [RTECS ]
XG3425000
| [F ]
23 | [TSCA ]
Yes | [HazardClass ]
6.1 | [PackingGroup ]
II | [Safety Profile]
Human poison by unspecified route. Human systemic effects by ingestion: nerve or sheath structural changes, extra-ocular muscle changes, sweating, and other effects. Flammable in the form of dust when exposed to heat or flame. Violent reaction with F2. When heated to decomposition it emits toxic fumes of Tl. Used as a rodenticide and fungicide, and in lenses and prisms, in highdensity liquids. See also THALLIUM COMPOUNDS and POWDERED METALS. | [Hazardous Substances Data]
7440-28-0(Hazardous Substances Data) |
| Questions And Answer | Back Directory | [History and Uses]
Thallium was discovered spectroscopically by Sir William Crookes in 1861. While searching for tellurium, he observed a beautiful green line in the spectrum of residues of a German sulfuric acid manufacturing plant. He named this element after the Latin word thallos meaning the budding green twig. In the following year, in 1862, both Crookes and Lamy independently isolated the metal.
Thallium occurs in nature in potash minerals and many sulfide ores. It is found in pyrites from which the metal is recovered. The metal also occurs in the minerals cooksite, lorandite, and hutchinsonite. The average concentration of thallium in the earth’s crust is estimated to be 0.85 mg/kg.
Thallium and its compounds have limited applications. It is used in insecticides and rodenticides. Thallium-mercury alloys are used for switches and closures for use at sub-zero temperatures. Another application is in making low melting glasses for electronic encapsulation. Thallium sulfide is used in photocells.
| [Physical Properties]
Metallic luster when freshly cut but attains a bluish-gray tinge on exposure to air resembling lead in appearance; tetragonal crystals; density 11.85 g/cm3 at 20°C; melts at 303.5° C; vaporizes at 1473° C; electrical resistivity 18 microhm–cm at 0°C and 74 microhm–cm at 303°C; tensile strength 1300 psi; surface tension at 327°C, 401 dynes/cm; insoluble in water; soluble in nitric and sulfuric acids; slightly soluble in hydrochloric acid.
| [Sources]
In the past, thallium was obtained as a by-product from smelting other metals. Thallium is a non-volatile heavy metal and, if released to the atmosphere by anthropogenic sources, may exist as an oxide (thallium oxide), hydroxide (TlOH), sulphate (thallium sulphate), or sulphide. Thallium exists in two chemical states (thallous and thallic). The thallous state is the more common and stable form. Thallous compounds are the most likely form to which common exposures occur in the environment. Thallium is present in air, water, and soil. Thallium is used mostly in the manufacture of electronic devices, switches, and closures. It also has limited use in the manufacture of special glasses and in medical procedures that evaluate heart disease. The levels of thallium in air and water are very low. The greatest exposure occurs from food, mostly home-grown fruits and green vegetables, contaminated by thallium. Small amounts of thallium are released into the air from coal-burning power plants, cement factories, and smelting operations. This thallium falls out of the air onto nearby fruit and vegetable gardens. Thallium enters food because it is easily taken up by plants through the roots. Very little is known on how much thallium is in specific foods grown or eaten. Cigarette smoking is also a source of thallium. People who smoke have twice as much thallium in their bodies than non-smokers. Although fish take up thallium from water, we do not know whether eating fish can increase thallium levels in our body. It has been estimated that the average person eats, on a daily basis, 2 parts thallium per billion parts (ppb) of food. Even though rat poison containing thallium was banned in 1972, accidental poisonings from old rat poison still occur, especially in children. Thallium is a heavy metallic element that exists in the environment mainly combined with other elements (primarily oxygen, sulphur, and halogens) in inorganic compounds. Thallium is quite stable in the environment, since it is neither transformed nor biodegraded.
| [Reactions]
Thallium forms all its compounds in two valence states, +1 (thallous) and +3 (thallic). The metal oxidizes slowly in air at ambient temperature but rapidly on heating, forming thallous oxide, Tl2O. This oxide oxidizes further on heating to form thallic oxide, Tl2O3. When exposed to air at ambient temperatures for several days thallium forms a heavy oxide crust.
Thallium reacts with water containing oxygen to form thallous hydroxide, TlOH, which is a relatively strong base, absorbing carbon dioxide and attacking glass.
The metal dissolves in nitric and sulfuric acid. The solution on evaporation crystallizes to yield thallous nitrate and sulfate. Reaction with hydrochloric acid is very slow.
Thallium burns in fluorine with incandescence. Reactions with other halogens form halides. Thallium combines with several elements forming binary compounds.
| [Toxicity]
Thallium and its compounds (particularly soluble salts) can cause serious or fatal poisoning from accidental ingestion or external application. Acute symptoms are nausea, vomiting, diarrhea, weakness, pain in extremities, convulsions, and coma. Chronic effects are weakness, pain in extremities, and rapid loss of hair. Thallium and its compounds are listed under Federal toxics regulations. It is listed by the US EPA as a priority pollutant metal in the environment.
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