Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Thiourea

Thiourea is a white solid which crystallizes in a rhombic bipyramidal structure and is odorless.

CAS 62-56-6 Warning

01 · Identification

What Thiourea is

Thiourea is a white solid which crystallizes in a rhombic bipyramidal structure and is odorless. It boils at 155 °C, melts at 182 °C.

Under the GHS it carries the signal word Warning. It is classed as carcinogens.

02 · Identifiers

Thiourea identifiers and molecular data

Thiourea CAS number and EC number

CAS number62-56-6
EC number200-543-5
Index number (CLP Annex VI)612-082-00-0

Thiourea molecular formula and molecular weight

Chemical class Carcinogens

Other names for Thiourea

  • thiocarbamide

03 · GHS classification

Thiourea hazard classification

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Thiourea pictograms and signal word

Signal wordWarning

Thiourea hazard class and category

GHS hazard classes Thiourea falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07
Carcinogenicity GHS chapter 3.6 Category 2 H351 GHS08
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 2 H411 GHS09

Thiourea hazard statements (H-codes)

Hazard statements assigned to Thiourea
CodeHazard statement
H351 Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H361d Suspected of damaging the unborn child.
H302 Harmful if swallowed.
H411 Toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to Thiourea. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for Thiourea

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Thiourea issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

Thiourea precautionary statements

CLP Annex VI assigns 11 precautionary statements to Thiourea. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Disposal

What has to happen to the contents and the empty container.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

Thiourea name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български тиоуреа тиокарбамид
Spanish español Tiourea tiocarbamida
Czech čeština thiomočovina thiokarbamid
Danish dansk thiourea thiourinstof
German Deutsch Thioharnstoff Thiocarbamid
Estonian eesti tiokarbamiid
Greek ελληνικά θειουρία θειοκαρβαμίδιο
English English thiourea thiocarbamide
French français thiourée thiocarbamide
Croatian hrvatski tiourea tiokarbamid
Italian italiano tiourea tiocarbammide
Latvian latviešu tiourīnviela tiokarbamīds
Lithuanian lietuvių tiošlapalas tiokarbamidas
Hungarian magyar tiourea tiokarbamid
Maltese Malti tijourea tijokarbammid
Dutch Nederlands thioureum thiocarbamide
Polish polski tiomocznik tiokarbamid
Portuguese português tioureia tiocarbamida
Romanian română tiouree tiocarbamidă
Slovak slovenčina tiomočovina tiokarbamid
Slovenian slovenščina tiosečnina tiokarbamid
Finnish suomi tiourea tiokarbamidi
Swedish svenska tiourea tiokarbamid

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

Thiourea GHS label elements

Everything CLP Annex VI fixes for Thiourea, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS08 Health hazard pictogramGHS07 Exclamation mark pictogramGHS09 Environment pictogram

Warning

Thiourea

  • Suspected of causing cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Suspected of damaging the unborn child.
  • Harmful if swallowed.
  • Toxic to aquatic life with long lasting effects.
  • Obtain special instructions before use.
  • Do not eat, drink or smoke when using this product.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF SWALLOWED:
  • IF exposed or concerned:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Get medical advice/attention.
  • Rinse mouth.
  • Collect spillage.
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Thiourea in the GHS label constructor →

07 · Health hazards

Thiourea health hazards and exposure limits

Thiourea hazard summary

Thiourea (thiocarbamide) has been used as a fixative in photography and photocopying. It has also been used as a rubber and neoprene antioxidant. Photocontact dermatitis caused by thiourea has been observed in users of shoe insoles, adhesive tape, wet suits, and neoprene weather strips. Alkylated thioureas include diethylthiourea (DTU), Diphenylthiourea (DPTU), Ethylenethiourea (ETU), Dimethylthiourea (DMTU), and ethylbutylthiourea (EBTU). [Marks, 239-40] Danger of skin sensitization and photo-contact sensitization; [MAK] See Ethylene thiourea,

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

Thiourea carcinogenicity classification

IARC classification Group 3 — Not classifiable as to its carcinogenicity to humans
IARC monographs Volume 79: (2001) Some Thyrotropic Agents

The Human Health Assessment Group in EPA's Office of Health and Environmental Assessment has evaluated thiourea for carcinogenicity. According to their analysis, the weight-of-evidence for thiourea is group B2, which is based on sufficient evidence in animals. No data available in humans. As a group B2 chemical, thiourea is considered a probable human carcinogen..

Source: Hazardous Substances Data Bank (HSDB)

Evaluation: There is inadequate evidence in humans for the carcinogenicity of thiourea. There is limited evidence in experimental animals for the carcinogenicity of thiourea. Overall evaluation: Thiourea is not classifiable as to its carcinogenicity to humans (Group 3).

Source: Hazardous Substances Data Bank (HSDB)

An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.

08 · Physical and chemical properties

Thiourea properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Thiourea boiling point

Property Value Conditions Source
Boiling point 155 °C (311 °F) range, midpoint shown CAMEO
Decomposes at boiling point decomposes HSDB

Thiourea melting point

Property Value Conditions Source
Melting point 182 °C (359.6 °F) ICSC
178 °C (352.4 °F) DOE PAC
177 °C (350.6 °F) range, midpoint shown HSDB

Thiourea density

Property Value Conditions Source
Density 1.4 g/cm³ ICSC
1.405 g/cm³ at 20 °C CAMEO
1.405 g/cm³ at 25 °C HSDB

Thiourea solubility

Property Value Conditions Source
Solubility Soluble in alcohol; sparingly soluble in ether. HSDB
In water, 1.42X10+5 mg/L at 25 °C at 25 °C HSDB
Soluble in water at 25 °C: 1 part in 11 at 25 °C HSDB

Thiourea vapor pressure

Property Value Conditions Source
Vapor pressure 1.41e-7 mmHg at 25 °C HSDB
0.0028 mmHg Haz-Map

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

09 · Handling and storage

Thiourea storage and handling

Thiourea safe storage

Separated from acids, food and feedstuffs, acrolein and oxidants. Cool. Well closed. Keep in a well-ventilated room.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

Thiourea storage conditions

Keep container tightly closed in a dry and well-ventilated place. Handle and store in inert gas. Storage class (TRGS 510): Non Combustible Solids.

Source: Hazardous Substances Data Bank (HSDB)

Thiourea incompatible materials

The solid peroxide produced by action of hydrogen peroxide & nitric acid on thiourea (& possibly a hydrogen peroxidate of thiourea dioxide) decomposed violently on drying in air, with evolution of sulfur dioxide & free sulfur.

Source: Hazardous Substances Data Bank (HSDB)

Thiourea reactivity

THIOUREA is a white crystalline material or powder, toxic, carcinogenic. When heated to decomposition it emits very toxic fumes of oxides of sulfur and oxides of nitrogen. Violent exothermic polymerization reaction with acrylaldehyde (acrolein) [MCA SD-85, 1961], violent decomposition of the reaction product with hydrogen peroxide and nitric acid [Bjorklund G. H. et al., Trans. R. Soc. Can.,1950, 44, p. 28], spontaneous explosion upon grinding with potassium chlorate [Soothill, D., Safety Management, 1992, 8(6), p. 11].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Thiourea in the storage compatibility matrix →

10 · Questions

Thiourea — frequently asked questions

What is the CAS number of Thiourea?

The CAS number of Thiourea is 62-56-6. Its EC number is 200-543-5.

What does a Thiourea label have to show?

Under CLP Annex VI the label for Thiourea carries the pictograms Health hazard, Exclamation mark and Environment and the signal word is Warning.

Is Thiourea flammable?

CLP Annex VI assigns Thiourea no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.

Is Thiourea a carcinogen?

CLP Annex VI assigns Thiourea H351 — suspected of causing cancer. That is category 2: the evidence points that way but is not conclusive. IARC places it in Group 3: not classifiable as to its carcinogenicity to humans.

What is the boiling point of Thiourea?

The boiling point reported for Thiourea is 155 °C (311 °F), range, midpoint shown (CAMEO).

What is the melting point of Thiourea?

The melting point reported for Thiourea is 182 °C (359.6 °F) (ICSC).

How should Thiourea be stored?

Keep container tightly closed in a dry and well-ventilated place. Handle and store in inert gas. Storage class (TRGS 510): Non Combustible Solids. (Hazardous Substances Data Bank (HSDB))

Nearby

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