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

Ethylenethiourea

Ethylenethiourea is needles, prisms from alcohol or amyl alcohol with a faint, amine odor.

CAS 96-45-7 C3H6N2S 102.16 g/mol Danger

01 · Identification

What Ethylenethiourea is

Ethylenethiourea is needles, prisms from alcohol or amyl alcohol with a faint, amine odor. Its molecular formula is C3H6N2S and its molecular weight is 102.16 g/mol. It boils at 271 °C, melts at 203 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

02 · Identifiers

Ethylenethiourea identifiers and molecular data

Ethylenethiourea CAS number and EC number

CAS number96-45-7
EC number202-506-9
Index number (CLP Annex VI)613-039-00-9

Ethylenethiourea molecular formula and molecular weight

Molecular formulaC3H6N2S
Molecular weight102.16 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for Ethylenethiourea

  • ethylene thiourea
  • imidazolidine-2-thione
  • 2-imidazoline-2-thiol

03 · GHS classification

Ethylenethiourea hazard classification

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

Ethylenethiourea pictograms and signal word

Signal wordDanger

Ethylenethiourea hazard class and category

GHS hazard classes Ethylenethiourea falls into
Hazard class Category From code Pictogram
Acute toxicity - oral GHS chapter 3.1 Category 4 H302 GHS07

Ethylenethiourea hazard statements (H-codes)

Hazard statements assigned to Ethylenethiourea
CodeHazard statement
H360D May damage the unborn child.
H302 Harmful if swallowed.

This page lists only the codes assigned to Ethylenethiourea. 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 Ethylenethiourea

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 Ethylenethiourea 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

Ethylenethiourea precautionary statements

CLP Annex VI assigns 4 precautionary statements to Ethylenethiourea. 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.

Prevention

What to do before and during handling so the hazard never happens.

Response

What to do once exposure, spillage or fire has already happened.

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

Ethylenethiourea 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 етилентиоуреа имидазолидин-2-тион2-имидазолин-2-тиол
Spanish español Etilentiourea imidazolidina-2-tiona2-imidazolina-2-tiol
Czech čeština ethylenthiomočovina imidazolidin-2-thion
Danish dansk ethylenthiourinstof imidazolidin-2-thion2-imidazolin-2-thiol
German Deutsch Eethylenthioharnstoff Imidazolidin-2-thion2-Imidazolin-2-thiol
Estonian eesti etüleentiokarbamiid imidasolidiin-2-tioon2-imidasoliin-2-tiool
Greek ελληνικά αιθυλενοθειουρία ιμιδαζολιδινο-2-θειόνη2-ιμιδαζολινο-2-θειόλη
English English ethylene thiourea imidazolidine-2-thione2-imidazoline-2-thiol
French français éthylènethio-urée imidazolidine-2-thione2-imidazoline-2-thiol
Croatian hrvatski etilen tiourea imidazolidin-2-tion2-imidazolin-2-tiol
Italian italiano etilentiourea imidazolidin-2-tione2-imidazolin-2-tiolo
Latvian latviešu etilēntiourīnviela imidazolidīn-2-tions2-imidazolīn-2-tiols
Lithuanian lietuvių etilentiokarbamidas imidazolidin-2-tionas2-imidazolin-2-tiolis
Hungarian magyar etiléntiokarbamid imidazolidin-2-tion2-imidazolin-2-tiol
Maltese Malti tijourea etilen imidażolidina-2-tijon2-imidażolina-2-tijol
Dutch Nederlands ethyleenthioureum imidazolidine-2-thion2-imidazoline-2-thiol
Polish polski 1,3-etylenotiomocznik imidazolidyno-2-tion
Portuguese português etilenotioureia imidazolidina-2-tiona2-imidazolina-2-tiol
Romanian română etilentiouree imidazolidin-2-tionă2-imidazolin-2-tiol
Slovak slovenčina etyléntiomočovina imidazolidín-2-tión2-imidazolín-2-tiol
Slovenian slovenščina etilen tiosečnina imidazolidin-2-tion2-imidazolin-2-tiol
Finnish suomi etyleenitiourea imidatsolidiini-2-tioni2-imidatsoliini-2-tioli
Swedish svenska etylentiourea imidazolidin-2-tion2-imidazolin-2-tiol

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

Ethylenethiourea GHS label elements

Everything CLP Annex VI fixes for Ethylenethiourea, 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 pictogram

Danger

Ethylenethiourea

  • May damage the unborn child.
  • Harmful if swallowed.
  • Do not eat, drink or smoke when using this product.
  • IF SWALLOWED:
  • Call a POISON CENTER/doctor/ if you feel unwell.
  • Rinse mouth.

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

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

07 · Health hazards

Ethylenethiourea health hazards and exposure limits

Ethylenethiourea hazard summary

Ethylene thiourea is used in the rubber industry and in the production of some fungicides. No information is available on the acute (short-term) or chronic (long-term) effects of ethylene thiourea in humans. In rodents chronically exposed to ethylene thiourea in their diet, effects on the thyroid have been observed. Ethylene thiourea has been shown to be a potent teratogen (causes birth defects) in rats orally or dermally exposed. A study of female workers occupationally exposed to ethylene thiourea did not report an increased incidence of thyroid cancer. In a study by the National Toxicology Program (NTP), an increased incidence of thyroid tumors in rats, and thyroid, liver, and pituitary gland tumors in mice exposed to ethylene thiourea were noted. EPA has classified ethylene thiourea as a Group B2, probable human carcinogen.

Source: EPA Hazardous Air Pollutants

Ethylenethiourea carcinogenicity classification

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

Studied by the US National Toxicology Program: TR-388: Toxicology and Carcinogenesis Studies of Ethylene Thiourea (CASRN 96-45-7) in F344 Rats and B6C3F1 Mice (Feed Studies) (1992 )

Cancer Classification: Group B2 Probable Human Carcinogen

Source: Hazardous Substances Data Bank (HSDB)

Ethylene Thiourea: reasonably anticipated to be a human carcinogen.

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.

Ethylenethiourea occupational exposure limits

US occupational exposure limits reported for Ethylenethiourea. PEL is enforceable (OSHA), REL is a recommendation (NIOSH), IDLH is the concentration at which escape becomes impossible without injury.
Limit Value Source
PEL none The National Institute for Occupational Safety and Health (NIOSH)
REL Ca Use encapsulated form. See Appendix A The National Institute for Occupational Safety and Health (NIOSH)
IDLH A potential occupational carcinogen. (NIOSH, 2024) CAMEO Chemicals
IDLH NIOSH considers ethylene thiourea to be a potential occupational carcinogen. Hazardous Substances Data Bank (HSDB)
IDLH Ca [N.D.] The National Institute for Occupational Safety and Health (NIOSH)

These are United States values. The European Union sets its own indicative and binding limits, and the figure that applies at a given workplace is the one in the local regulation — not the one shown here.

08 · Physical and chemical properties

Ethylenethiourea 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.

Ethylenethiourea boiling point

Property Value Conditions Source
Boiling point 271.39 °C (520.5 °F) range, midpoint shown NIOSH
271.39 °C (520.5 °F) range, midpoint shown, at 760 mmHg CAMEO

Ethylenethiourea melting point

Property Value Conditions Source
Melting point 203 °C (397.4 °F) HSDB
192 °C (377.6 °F) HSDB
200 °C (392 °F) NIOSH

Ethylenethiourea density

Property Value Conditions Source
Density 28 g/cm³ at 20 °C ICSC

Ethylenethiourea solubility

Property Value Conditions Source
Solubility Soluble in ethanol; slightly soluble in dimethyl sulfoxide; insoluble in ethyl ether, benzene, chloroform HSDB
Moderately soluble in methanol, ethanol, ethylene glycol, pyridine; insoluble in acetone, ether, chloroform, benzene, ligroin HSDB
Soluble in ethanol; insoluble in ethyl ether and benzene. HSDB

Ethylenethiourea vapor pressure

Property Value Conditions Source
Vapor pressure 16 mmHg NIOSH
0.9976 mmHg at 25 °C ICSC

Ethylenethiourea flash point

Property Value Conditions Source
Flash point 252.22 °C (486 °F) NIOSH
252 °C (485.6 °F) ICSC

Ethylenethiourea lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) Combustible Solid NIOSH

Ethylenethiourea odor threshold

Property Value Conditions Source
Odor threshold Odorless HSDB

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

09 · Handling and storage

Ethylenethiourea storage and handling

Ethylenethiourea safe storage

Separated from strong oxidants. Store in an area without drain or sewer access.

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

Ethylenethiourea storage conditions

Store in tightly closed containers in a cool, well ventilated area away from strong oxidizers, acids, acid anhydrides, acrolein. Store in a refrigerator or a cool, dry place. A regulated marked area should be established where this chemical is handled, used, or stored ...

Source: Hazardous Substances Data Bank (HSDB)

Ethylenethiourea incompatible materials

Strong oxidizers, acids, acid anhydrides, acrolein.

Source: Hazardous Substances Data Bank (HSDB)

Ethylenethiourea reactivity

ETHYLENE THIOUREA may be sensitive to prolonged exposure to light. Incompatible with acids, diazo and azo compounds, halocarbons, isocyanates, aldehydes, alkali metals, nitrides, hydrides, and other strong reducing agents. Reactions with these materials generate heat and in many cases hydrogen gas. May react with acids to liberate hydrogen sulfide.

Source: CAMEO Chemicals

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

10 · Questions

Ethylenethiourea — frequently asked questions

What is the CAS number of Ethylenethiourea?

The CAS number of Ethylenethiourea is 96-45-7. Its EC number is 202-506-9.

What is the chemical formula of Ethylenethiourea?

The molecular formula of Ethylenethiourea is C3H6N2S and its molecular weight is 102.16 g/mol.

What does a Ethylenethiourea label have to show?

Under CLP Annex VI the label for Ethylenethiourea carries the pictograms Health hazard and Exclamation mark and the signal word is Danger.

Is Ethylenethiourea flammable?

CLP Annex VI assigns Ethylenethiourea 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. The flash point reported for it is 252.22 °C (486 °F) (NIOSH).

Is Ethylenethiourea a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Ethylenethiourea. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health. IARC places it in Group 3: not classifiable as to its carcinogenicity to humans.

What is the exposure limit for Ethylenethiourea?

The US occupational exposure limit reported for Ethylenethiourea is none (The National Institute for Occupational Safety and Health (NIOSH)). Limits differ by country: the EU sets its own indicative and binding values, and the figure that applies at a given workplace is the one in the local regulation.

What is the boiling point of Ethylenethiourea?

The boiling point reported for Ethylenethiourea is 271.39 °C (520.5 °F), range, midpoint shown (NIOSH).

What is the melting point of Ethylenethiourea?

The melting point reported for Ethylenethiourea is 203 °C (397.4 °F) (HSDB).

How should Ethylenethiourea be stored?

Store in tightly closed containers in a cool, well ventilated area away from strong oxidizers, acids, acid anhydrides, acrolein. Store in a refrigerator or a cool, dry place. A regulated marked area should be established where this chemical is handled, used, or stored ... (Hazardous Substances Data Bank (HSDB))

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