Provenance

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

Build a label

Substance profile

N-methyl-2-pyrrolidone

N-methyl-2-pyrrolidone is a clear liquid with a mild amine odor.

CAS 872-50-4 C5H9NO 99.13 g/mol Danger

01 · Identification

What N-methyl-2-pyrrolidone is

N-methyl-2-pyrrolidone is a clear liquid with a mild amine odor. Its molecular formula is C5H9NO and its molecular weight is 99.13 g/mol. It boils at 202 °C, melts at -25 °C, is miscible with water.

Under the GHS it carries the signal word Danger. It is classed as teratogens.

02 · Identifiers

N-methyl-2-pyrrolidone identifiers and molecular data

N-methyl-2-pyrrolidone CAS number and EC number

CAS number872-50-4
EC number212-828-1
Index number (CLP Annex VI)606-021-00-7

N-methyl-2-pyrrolidone molecular formula and molecular weight

Molecular formulaC5H9NO
Molecular weight99.13 g/mol
Chemical class Teratogens

Other names for N-methyl-2-pyrrolidone

  • 1-methyl-2-pyrrolidone

03 · GHS classification

N-methyl-2-pyrrolidone hazard classification

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

N-methyl-2-pyrrolidone pictograms and signal word

Signal wordDanger

N-methyl-2-pyrrolidone hazard class and category

GHS hazard classes N-methyl-2-pyrrolidone falls into
Hazard class Category From code Pictogram
Skin corrosion/irritation GHS chapter 3.2 Category 2 H315 GHS07
Serious eye damage/eye irritation GHS chapter 3.3 Category 2A H319 GHS07
Specific target organ toxicity - single exposure GHS chapter 3.8 Category 3 H335 GHS07

N-methyl-2-pyrrolidone hazard statements (H-codes)

Hazard statements assigned to N-methyl-2-pyrrolidone
CodeHazard statement
H360D May damage the unborn child.
H335 May cause respiratory irritation.
H315 Causes skin irritation.
H319 Causes serious eye irritation.

This page lists only the codes assigned to N-methyl-2-pyrrolidone. 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 N-methyl-2-pyrrolidone

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 N-methyl-2-pyrrolidone 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

N-methyl-2-pyrrolidone precautionary statements

CLP Annex VI assigns 9 precautionary statements to N-methyl-2-pyrrolidone. 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.

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

N-methyl-2-pyrrolidone 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 N -метил-2-пиролидон 1-метил-2-пиролидон
Spanish español N -metil-2-pirrolidona 1-metil-2-pirrolidona
Czech čeština N -methyl-2-pyrrolidon 1-methylpyrrolidin-2-on
Danish dansk N-methyl-2-pyrrolidon 1-methyl-2-pyrrolidon
German Deutsch N-Methyl-2-pyrrolidon 1-Methyl-2-pyrrolidon
Estonian eesti N -metüül-2-pürrolidoon 1-metüül-2-pürrolidoon
Greek ελληνικά N-μεθυλο-2-πυρρολιδόνη 1-μεθυλο-2-πυρρολιδόνη
English English N-methyl-2-pyrrolidone 1-methyl-2-pyrrolidone
French français N -méthyl-2-pyrrolidone 1-méthyl-2-pyrrolidone
Croatian hrvatski N-metil-2-pirolidon 1-metil- 2-pirolidon
Italian italiano N-metil-2-pirrolidone 1-metil-2-pirrolidone
Latvian latviešu N -metil-2-pirolidons 1-metil-2-pirolidons
Lithuanian lietuvių N-metil-2-pirolidonas 1-metil-2-pirolidonas
Hungarian magyar N-metil-2-pirrolidon 1-metil-2-pirrolidon
Maltese Malti N-Metil-2-pirrolidone 1-Metil-2-pirrolidone
Dutch Nederlands N -methyl-2-pyrrolidon 1-methyl-2-pyrrolidon
Polish polski N -metylo-2-pirolidon 1-metylo-2-pirolidon
Portuguese português N -metil-2-pirrolidona 1-metil-2-pirrolidona
Romanian română N-metil-2-pirolidonă 1-metil-2-pirolidonă
Slovak slovenčina N-metyl-2-pyrolidón 1-metylpyrolidín-2-ón
Slovenian slovenščina N-metil-2-pirolidon 1-metil-2-pirolidon
Finnish suomi N-metyyli-2-pyrrolidoni 1-metyyli-2-pyrrolidoni
Swedish svenska N-metyl-2-pyrrolidon 1-metyl-2-pyrrolidon

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

N-methyl-2-pyrrolidone GHS label elements

Everything CLP Annex VI fixes for N-methyl-2-pyrrolidone, 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

N-methyl-2-pyrrolidone

  • May damage the unborn child.
  • May cause respiratory irritation.
  • Causes skin irritation.
  • Causes serious eye irritation.
  • Wash thoroughly after handling.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • IF ON SKIN:
  • IF IN EYES:
  • Get medical advice/attention.
  • If skin irritation occurs:
  • If eye irritation persists:
  • Remove contact lenses, if present and easy to do. Continue rinsing.
  • Wash with plenty of water/

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

Need this as an actual label? Open N-methyl-2-pyrrolidone in the GHS label constructor →

07 · Health hazards

N-methyl-2-pyrrolidone health hazards and exposure limits

N-methyl-2-pyrrolidone hazard summary

It is absorbed through the skin; a severe eye irritant; [CSH, p. 291] It is mainly an irritant, but it can cause severe contact dermatitis due to prolonged contact. [Kanerva, p. 1816] Experimental animals experience lethargy and respiratory difficulty after inhalation. [HSDB] Some animal studies found fetal loss and birth defects after high doses during early pregnancy. [Frazier, p. 345] NMP is a cyclic amide used as a solvent, catalyst, formulating agent, and graffiti remover. Significant absorption occurs through the skin. 2-HMSI can be used for biological monitoring of workers. [Akesson B, Carnerup MA, Jonsson BAG. Evaluation of exposure biomarkers from percutaneous absorption of N-methyl-2-pyrrolidone. Scand J Work Environ 2004;30(4):306-312] In high-dose animal studies, adverse effects include CNS depression and changes to the liver, kidneys, and blood cells. [ACGIH] A skin and eye irritant; [ICSC] Danger of cutaneous absorption; [AIHA]

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

08 · Physical and chemical properties

N-methyl-2-pyrrolidone 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.

N-methyl-2-pyrrolidone boiling point

Property Value Conditions Source
Boiling point 202 °C (395.6 °F) at 760 mmHg HSDB
202.22 °C (396 °F) at 760 mmHg CAMEO
202 °C (395.6 °F) ICSC

N-methyl-2-pyrrolidone melting point

Property Value Conditions Source
Melting point -25 °C (-13 °F) HSDB
-22.78 °C (-9 °F) CAMEO
-24.4 °C (-11.9 °F) ICSC

N-methyl-2-pyrrolidone density

Property Value Conditions Source
Density 1.03 g/cm³ ICSC
1.027 g/cm³ at 25 °C HSDB
1.03 g/cm³ at 25 °C CAMEO

N-methyl-2-pyrrolidone solubility

Property Value Conditions Source
Solubility Miscible with water, alcohol, ether, acetone, ethyl acetate, chloroform, benzene HSDB
Miscible with castor oil HSDB
Miscible with lower alcohols and ketones HSDB

N-methyl-2-pyrrolidone vapor pressure

Property Value Conditions Source
Vapor pressure 0.345 mmHg at 25 °C HSDB
0.2925 mmHg at 25 °C ICSC

N-methyl-2-pyrrolidone flash point

Property Value Conditions Source
Flash point 95.56 °C (204 °F) HSDB
86 °C (186.8 °F) ICSC

N-methyl-2-pyrrolidone autoignition temperature

Property Value Conditions Source
Autoignition temperature 346.11 °C (655 °F) HSDB
245 °C (473 °F) ICSC

N-methyl-2-pyrrolidone lower explosive limit (LEL)

Property Value Conditions Source
Lower explosive limit (LEL) 1.3 % by volume ICSC
Expolsion Prevention: Above 96 °C use a closed system and ventilation. HSDB
Above 96 °C explosive vapor/air mixtures may be formed. HSDB

N-methyl-2-pyrrolidone upper explosive limit (UEL)

Property Value Conditions Source
Upper explosive limit (UEL) 9.5 % by volume ICSC

N-methyl-2-pyrrolidone vapor density

Property Value Conditions Source
Vapor density 3.4 (air = 1) HSDB

N-methyl-2-pyrrolidone odor threshold

Property Value Conditions Source
Odor threshold Odor Threshold Low: 4.0 [ppm] Haz-Map
Odor Threshold High: 10.0 [ppm] Haz-Map
Odor thresholds from CSH Haz-Map

N-methyl-2-pyrrolidone critical temperature and pressure

Property Value Conditions Source
Critical temperature and pressure 451 °C (843.8 °F) HSDB

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

09 · Fire and explosion

N-methyl-2-pyrrolidone fire and explosion behaviour

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

N-methyl-2-pyrrolidone fire potential

Combustible when exposed to heat, open flame, or powerful oxidizers.

Source: Hazardous Substances Data Bank (HSDB)

10 · Handling and storage

N-methyl-2-pyrrolidone storage and handling

N-methyl-2-pyrrolidone safe storage

Dry. Ventilation along the floor. Separated from strong oxidants, strong acids, strong bases, copper and plastics.

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

N-methyl-2-pyrrolidone storage conditions

Small quantities can be stored in polyethylene, polypropylene, or clear glass bottles.

Source: Hazardous Substances Data Bank (HSDB)

N-methyl-2-pyrrolidone incompatible materials

Reacts with sulfur or carbon disulfide at high temperatures and pressures.

Source: Hazardous Substances Data Bank (HSDB)

N-methyl-2-pyrrolidone reactivity

This amine is a very mild chemical base. It does tend to neutralize acids to form salts plus water. The amount of heat that is evolved per mole of amine in a neutralization is largely independent of the strength of the amine as a base. Amines may be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen is generated by amines in combination with strong reducing agents, such as hydrides.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check N-methyl-2-pyrrolidone in the storage compatibility matrix →

11 · Questions

N-methyl-2-pyrrolidone — frequently asked questions

What is the CAS number of N-methyl-2-pyrrolidone?

The CAS number of N-methyl-2-pyrrolidone is 872-50-4. Its EC number is 212-828-1.

What is the chemical formula of N-methyl-2-pyrrolidone?

The molecular formula of N-methyl-2-pyrrolidone is C5H9NO and its molecular weight is 99.13 g/mol.

What does a N-methyl-2-pyrrolidone label have to show?

Under CLP Annex VI the label for N-methyl-2-pyrrolidone carries the pictograms Health hazard and Exclamation mark and the signal word is Danger.

Is N-methyl-2-pyrrolidone flammable?

CLP Annex VI assigns N-methyl-2-pyrrolidone 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 95.56 °C (204 °F) (HSDB).

Is N-methyl-2-pyrrolidone a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for N-methyl-2-pyrrolidone. 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.

What is the boiling point of N-methyl-2-pyrrolidone?

The boiling point reported for N-methyl-2-pyrrolidone is 202 °C (395.6 °F), at 760 mmHg (HSDB).

What is the melting point of N-methyl-2-pyrrolidone?

The melting point reported for N-methyl-2-pyrrolidone is -25 °C (-13 °F) (HSDB).

How should N-methyl-2-pyrrolidone be stored?

Small quantities can be stored in polyethylene, polypropylene, or clear glass bottles. (Hazardous Substances Data Bank (HSDB))

Get the free GHS / CLP / OSHA deadline calendar

Verified 2026–2029 compliance dates in one PDF — plus alerts when the rules change.