Thallium

CAS ID #: 44-28-0

Affected Organ Systems: Gastrointestinal (Digestive), Hepatic (Liver), Neurological (Nervous System), Renal (Urinary System or Kidneys)

Cancer Classification: EPA: Inadequate information to assess carcinogenic potential. IARC: Not evaluated. NTP: Not evaluated

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Chemical Classification: Inorganic substances

Summary: 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.. 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.. 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.