Record Information
Version2.0
Creation Date2009-03-06 18:58:05 UTC
Update Date2014-12-24 20:21:06 UTC
Accession NumberT3D0101
Identification
Common NameThorium
ClassSmall Molecule
DescriptionThorium is a natural radioactive chemical element with the symbol Th and atomic number 90. In nature, virtually all thorium is found as thorium-232, and it decays by emitting an alpha particle, and has a half-life of about 14.05 billion years (other, trace-level isotopes of thorium are short-lived intermediates of decay chains). It is estimated to be about four times more abundant than uranium in the Earth's crust and is a by-product of the extraction of rare earths from monazite sands. -- Wikipedia.
Compound Type
  • Food Toxin
  • Industrial/Workplace Toxin
  • Inorganic Compound
  • Metabolite
  • Metal
  • Natural Compound
  • Pollutant
  • Radioactive
  • Radioactive Isotope
  • Thorium Compound
Chemical Structure
Thumb
Synonyms
Synonym
232Th
90Th
Thorium 232
Thorium, isotope of mass 232
Thorium-232
Chemical FormulaTh
Average Molecular Mass232.038 g/mol
Monoisotopic Mass232.038 g/mol
CAS Registry Number7440-29-1
IUPAC Namethorium
Traditional Namethorium
SMILES[Th]
InChI IdentifierInChI=1S/Th
InChI KeyInChIKey=ZSLUVFAKFWKJRC-UHFFFAOYSA-N
Chemical Taxonomy
Description belongs to the class of inorganic compounds known as homogeneous actinide compounds. These are inorganic compounds containing only metal atoms,with the largest atom being a transition metal atom.
KingdomInorganic compounds
Super ClassHomogeneous metal compounds
ClassHomogeneous actinide compounds
Sub ClassNot Available
Direct ParentHomogeneous actinide compounds
Alternative ParentsNot Available
Substituents
  • Homogeneous actinide
Molecular FrameworkNot Available
External Descriptors
Biological Properties
StatusDetected and Not Quantified
OriginExogenous
Cellular Locations
  • Cytoplasm
  • Extracellular
Biofluid LocationsNot Available
Tissue LocationsNot Available
PathwaysNot Available
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
StateSolid
AppearanceThorium is an air-stable silvery-white solid metal. (2)
Experimental Properties
PropertyValue
Melting Point2115°K (1842°C, 3348°F)
Boiling Point5061°K (4788 °C, 8650 °F)
SolubilityNot Available
LogPNot Available
Predicted Properties
PropertyValueSource
logP0ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count0ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area0 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity0 m³·mol⁻¹ChemAxon
Polarizability1.78 ųChemAxon
Number of Rings0ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash KeyDeposition DateView
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-001i-0090000000-d036f293e0cb3833940e2016-08-02View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-001i-0090000000-d036f293e0cb3833940e2016-08-02View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-001i-0090000000-d036f293e0cb3833940e2016-08-02View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-001i-0090000000-74094fab40130bbbe2aa2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-001i-0090000000-74094fab40130bbbe2aa2016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-001i-0090000000-74094fab40130bbbe2aa2016-08-03View Spectrum
Toxicity Profile
Route of ExposureInhalation (2)
Mechanism of ToxicityThe ionizing radiation produced by thorium causes cellular damage that includes DNA breakage, accurate or inaccurate repair, apoptosis, gene mutations, chromosomal change, and genetic instability. This leads to loss of normal cell and tissue homeostasis, and development of malignancy. Ionizing radiation that does not directly damage DNA can produce reactive oxygen intermediates that directly affect the stability of p53, an important enzyme in cell-cycle regulation, and produce oxidative damage to individual bases in DNA and point mutations by mispairing during DNA replication. (3)
MetabolismExposure to thorium can occur following inhalation, ingestion, or dermal exposure. Once in the body thorium accumulates mainly in the liver, spleen, lymph nodes, lungs, and bone. Transferrin plays a major role in the transport and cellular uptake of thorium. Thorium may combine with oxygen to form thorotrast (thorium dioxide), a colloid which may affect protein uptake. Thorium and thorotrast are excreted mainly in the faeces. (4)
Toxicity ValuesNot Available
Lethal DoseNot Available
Carcinogenicity (IARC Classification)1, carcinogenic to humans. (1)
Uses/SourcesThorium can also be used as a fuel for generating nuclear energy. Thorium is used as an alloying element in magnesium, used in aircraft engines, imparting high strength and creep resistance at elevated temperatures. Thorium is also used as an alloying agent in gas tungsten arc welding (GTAW) to increase the melting temperature of tungsten electrodes and improve arc stability. Thorium is used to coat tungsten wire used in electronic equipment, improving the electron emission of heated cathodes. Thorium is used as a fertile material for producing nuclear fuel. Thorium is a very effective radiation shield, although it has not been used for this purpose as much as lead or depleted uranium. Uranium-thorium age dating has been used to date hominid fossils. (2)
Minimum Risk LevelNot Available
Health EffectsLungs and other internal organs can be penetrated by the alpha radiation produced by thorium. As a result, exposure to an aerosol of thorium can lead to increased risk of cancers of the lung, pancreas and blood. Exposure to thorium internally leads to increased risk of liver diseases. (2)
SymptomsExposure to high doses of ionizing radiation results in acute radiation syndrome, which can cause skin burns, hair loss, nausea, vomiting, dizziness, disorientation, low blood pressure, headache, fatigue, weakness, fever, birth defects, illness, infection, and death. (3, 5)
TreatmentTreatment reversing the effects of irradiation is currently not possible. Anaesthetics and antiemetics are administered to counter the symptoms of exposure, as well as antibiotics for countering secondary infections due to the resulting immune system deficiency. (5)
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
HMDB IDHMDB29215
PubChem Compound ID23960
ChEMBL IDNot Available
ChemSpider ID22399
KEGG IDC19157
UniProt IDNot Available
OMIM ID
ChEBI ID33385
BioCyc IDNot Available
CTD IDD013910
Stitch IDThorium
PDB IDNot Available
ACToR ID7977
Wikipedia LinkThorium
References
Synthesis ReferenceNot Available
MSDST3D0101.pdf
General References
  1. International Agency for Research on Cancer (2014). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. [Link]
  2. Wikipedia. Thorium. Last Updated 7 July 2009. [Link]
  3. ATSDR - Agency for Toxic Substances and Disease Registry (1999). Toxicological profile for ionizing radiation. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). [Link]
  4. ATSDR - Agency for Toxic Substances and Disease Registry (1990). Toxicological profile for thorium. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). [Link]
  5. Wikipedia. Radiation poisoning. Last Updated 22 August 2009. [Link]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available

Targets

1. DNA
General Function:
Used for biological information storage.
Specific Function:
DNA contains the instructions needed for an organism to develop, survive and reproduce.
Molecular Weight:
2.15 x 1012 Da
References
  1. ATSDR - Agency for Toxic Substances and Disease Registry (1999). Toxicological profile for ionizing radiation. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). [Link]