Thiourea

**Semantic type:** Hazardous or Poisonous Substance

**Definition:** A white crystalline solid, both naturally occurring and synthetic, that is soluble in water, ammonium thiocyanate solution and ethanol. In the past, it was used as a photographic toning agent, a component of hair preparations and a dry cleaning agent. Currently, it is only used in animal glue liquefiers and silver tarnish removers. When heated to decomposition, thiourea emits toxic fumes of nitrogen oxides and sulfur oxides. Long-term exposure of humans to thiourea may cause bone marrow damage, resulting in reduced levels of red blood cells, white blood cells and/or platelets. It is reasonably anticipated to be a human carcinogen. (NCI05)

**Synonyms:** - 2-Thiourea - Isothiourea - Pseudothiourea - Sulfourea - THIOUREA - THU - Thiocarbamide - USAF EK-497