Thiourea

Thiourea was investigated as a food preservative and antioxidant. It is prohibited from use in human food in the United States.

Where it is and isn’t permitted

Status of Thiourea by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationProhibited21 CFR 189.190retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFANot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.

What it is made from

Manufactured from ammonium thiocyanate or by reacting hydrogen sulfide with cyanamide. Its uses today are industrial rather than alimentary.

  • Vegan
  • Vegetarian
InChIKey
UMGDCJDMYOKAJW-UHFFFAOYSA-N
PubChem
CID 2723790

Every name it appears under

61 recorded names. A label may use any of them.

CAS registry number

  • 17356-08-0
  • 62-56-6

As it appears in regulation

  • Thiourea

Other names

  • .beta.-Thiopseudourea
  • 2-Thio-Pseudourea
  • 2-Thio-Urea
  • 2-Thiopseudourea
  • 2-Thiourea
  • aminothioamide
  • aminothiocarboxamide
  • beta-Thiopseudourea
  • Carbamimidothioic acid
  • carbonothioic diamide
  • CAS-62-56-6
  • Caswell No. 855
  • CCRIS 588
  • EPA Pesticide Chemical Code 080201
  • GYV9AM2QAG
  • HSDB 1401
  • Isothiourea
  • Propylthiouracil EP Impurity A
  • PROPYLTHIOURACIL IMPURITY A [EP IMPURITY]
  • Pseudothiourea
  • Pseudourea, 2-thio-
  • RCRA waste no. U219
  • RCRA waste number U219
  • sulfocarbamide
  • Sulfourea
  • Sulfouren
  • Sulourea
  • thio-urea
  • Thiocarbamid
  • Thiocarbamide
  • Thiocarbonic acid diamide
  • Thiocarbonic diamide
  • Thioharnstoff
  • Thiokarbamid
  • Thiomocovina
  • thiopseudourea
  • THIOUREA
  • Thiourea ACS Reagent Grade
  • Thiourea, 99%
  • Thiourea, >=99.999% (metals basis)
  • THIOUREA, ACS
  • Thiourea, ACS reagent, >=99.0%
  • Thiourea, JIS special grade, >=98.0%
  • Thiourea, LR, >=98%
  • Thiourea, p.a., ACS reagent, 99.0%
  • Thiourea, ReagentPlus(R), >=99.0%
  • Thiourea-(1)N2
  • Thiourea-1?N2
  • Thiourea; Propylthiouracil EP Impurity A
  • thiourea; thiocarbamide
  • Thiuronium
  • TOU
  • Tsizp 34
  • Urea, 2-thio-
  • Urea, thio-
  • Urea, thio- (8CI)
  • USAF EK-497
  • WLN: ZYZUS

Hazard reference values

No reference value for this substance in the sources we hold.

Evidence and how bodies read it

Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.

Sources for this page

  • ecfr retrieved 2026-09-07

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable:/api/v1/additives/thiourea.json