Substance profile
Hexamethylphosphoramide
Hexamethylphosphoramide is colorless, mobile liquid with an aromatic odor.
01 · Identification
What Hexamethylphosphoramide is
Hexamethylphosphoramide is colorless, mobile liquid with an aromatic odor. Its molecular formula is C6H18N3OP and its molecular weight is 179.2 g/mol. It boils at 233 °C, melts at 6.1 °C, is miscible with water.
Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).
02 · Identifiers
Hexamethylphosphoramide identifiers and molecular data
Hexamethylphosphoramide CAS number and EC number
Hexamethylphosphoramide molecular formula and molecular weight
Other names for Hexamethylphosphoramide
- hexamethylphosphoric triamide
03 · GHS classification
Hexamethylphosphoramide hazard classification
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
Hexamethylphosphoramide pictograms and signal word
Hexamethylphosphoramide hazard class and category
| Hazard class | Category | From code | Pictogram |
|---|---|---|---|
| Germ cell mutagenicity GHS chapter 3.5 | Category 1A or 1B | H340 | GHS08 |
| Carcinogenicity GHS chapter 3.6 | Category 1A or 1B | H350 | GHS08 |
Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.
Hexamethylphosphoramide hazard statements (H-codes)
| Code | Hazard statement |
|---|---|
| H350 | May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H340 | May cause genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
This page lists only the codes assigned to Hexamethylphosphoramide. 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 Hexamethylphosphoramide
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 Hexamethylphosphoramid… 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
Hexamethylphosphoramide precautionary statements
CLP Annex VI assigns 4 precautionary statements to Hexamethylphosphoramide. 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
Hexamethylphosphoramide 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 | хексаметилфосфорен триамид хексаметилфосфорамид |
| Spanish español | Hexametiltriamida fosfórica hexametilfosforamida |
| Czech čeština | hexamethylfosforamid |
| Danish dansk | hexamethylphosphortriamid hexamethylphosphoramid |
| German Deutsch | Hexamethylphosphorsäuretriamid Hexamethylphosphoramid |
| Estonian eesti | heksametüülfosfortriamiid heksametüülfosforamiid |
| Greek ελληνικά | εξαμεθυλοφωσφορικό τριαμίδιο εξαμεθυλοφωσφοραμίδιο |
| English English | hexamethylphosphoric triamide hexamethylphosphoramide |
| French français | triamide hexaméthylphosphorique hexaméthylphosphoramide |
| Croatian hrvatski | heksametil-fosforov triamid heksametil-fosforamid |
| Italian italiano | esametilfosforamide triamide esametilfosforica |
| Latvian latviešu | heksametilfosfortriamīds heksametilfosforamīds |
| Lithuanian lietuvių | heksametilfosfato triamidas heksametilfosforamidas |
| Hungarian magyar | hexametil-foszforsav-triamid hexametil-foszfor-amid |
| Maltese Malti | triammid essametilfosforiku eksametilfosforammid |
| Dutch Nederlands | hexamethylfosforzuurtriamide hexamethylfosforamide |
| Polish polski | heksametylofosforotriamid heksametylotriamid kwasu fosforowego(V) |
| Portuguese português | triamida hexametilfosfórica hexametilfosforamida |
| Romanian română | triamidă hexametilfosforică hexametilfosforamidă |
| Slovak slovenčina | hexametylfosfortriamid tris(dimetylamid) kyseliny fosforečnej |
| Slovenian slovenščina | heksametilfosforjev triamid heksametilfosforamid |
| Finnish suomi | heksametyylifosforitriamidi heksametyylifosforamidi |
| Swedish svenska | hexametylfosfortriamid hexametylfosforamid |
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
Hexamethylphosphoramide GHS label elements
Everything CLP Annex VI fixes for Hexamethylphosphoramide, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.
Danger
Hexamethylphosphoramide
- May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
- May cause genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
- Obtain special instructions before use.
- Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/…
- IF exposed or concerned:
- Get medical advice/attention.
Supplier name, address and telephone number· Product identifier·Nominal quantity
Need this as an actual label? Open Hexamethylphosphoramide in the GHS label constructor →
07 · Health hazards
Hexamethylphosphoramide health hazards and exposure limits
Hexamethylphosphoramide hazard summary
Hexamethylphosphoramide is no longer used in large quantities in the United States. No information is available on the acute (short-term), chronic (long-term), reproductive, developmental, or carcinogenic effects of hexamethylphosphoramide in humans. Acute animal studies have reported effects on the kidneys and lungs from oral exposure to hexamethylphosphoramide, while chronic oral studies in animals have reported an increased incidence of lung disease. An increased incidence of nasal tumors from inhalation exposure to hexamethylphosphoramide was reported in rats. EPA has not classified hexamethylphosphoramide for carcinogenicity; however, the International Agency for Research on Cancer (IARC) has classified it as a Group 2B, possible human carcinogen.
Source: EPA Hazardous Air Pollutants
Hexamethylphosphoramide carcinogenicity classification
Evaluation: No epidemiological data relevant to the carcinogeniciy of hexamethylphosphoramide were available. There is sufficient evidence in experimental animals for the carcinogenicity of hexamethylphosphoramide. Overall evaluation: Hexamethylphosphoramide is possibly carcinogenic to humans (Group 2B).
Source: Hazardous Substances Data Bank (HSDB)
Hexamethylphosphoramide: 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.
Hexamethylphosphoramide occupational exposure limits
| Limit | Value | Source |
|---|---|---|
| PEL | none | The National Institute for Occupational Safety and Health (NIOSH) |
| REL | Ca See Appendix A | The National Institute for Occupational Safety and Health (NIOSH) |
| IDLH | A potential occupational carcinogen. (NIOSH, 2024) | CAMEO Chemicals |
| IDLH | NIOSH considers hexamethyl phosphoramide 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
Hexamethylphosphoramide 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.
Hexamethylphosphoramide boiling point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 233 °C (451.4 °F) | at 760 mmHg | HSDB |
| 232.78 °C (451 °F) | NIOSH | ||
| 232.78 °C (451 °F) | at 760 mmHg | CAMEO |
Hexamethylphosphoramide melting point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Melting point | 6.11 °C (43 °F) | NIOSH | |
| 7.2 °C (45 °F) | ICSC |
Hexamethylphosphoramide density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Density | 1.03 g/cm³ | NIOSH | |
| 1.03 g/cm³ | at 20 °C | HSDB | |
| 1.024 g/cm³ | at 25 °C | CAMEO |
Hexamethylphosphoramide solubility
| Property | Value | Conditions | Source |
|---|---|---|---|
| Solubility | MISCIBLE WITH WATER & WITH MOST ORG LIQ; IMMISCIBLE WITH HIGH-BOILING SATURATED HYDROCARBONS | HSDB | |
| Miscible | NIOSH | ||
| Solubility in water: very good | ICSC |
Hexamethylphosphoramide vapor pressure
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor pressure | 0.03 mmHg | HSDB | |
| 0.07 mmHg | at 25 °C | CAMEO |
Hexamethylphosphoramide flash point
| Property | Value | Conditions | Source |
|---|---|---|---|
| Flash point | 104.44 °C (220 °F) | NIOSH | |
| 105.56 °C (222 °F) | CAMEO | ||
| 105 °C (221 °F) | ICSC |
Hexamethylphosphoramide lower explosive limit (LEL)
| Property | Value | Conditions | Source |
|---|---|---|---|
| Lower explosive limit (LEL) | Class IIIB Combustible Liquid: Fl.P. at or above 200 °F. | NIOSH |
Hexamethylphosphoramide vapor density
| Property | Value | Conditions | Source |
|---|---|---|---|
| Vapor density | 6.18 (air = 1) | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
09 · Handling and storage
Hexamethylphosphoramide storage and handling
Hexamethylphosphoramide safe storage
Ventilation along the floor. Separated from acids and oxidants.
Source: ILO-WHO International Chemical Safety Cards (ICSCs)
Hexamethylphosphoramide storage conditions
PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/
Source: Hazardous Substances Data Bank (HSDB)
Hexamethylphosphoramide incompatible materials
Oxidizers, strong acids, chemically active metals (e.g., potassium, sodium, magnesium, zinc).
Source: Hazardous Substances Data Bank (HSDB)
Hexamethylphosphoramide reactivity
HEXAMETHYLPHOSPHORAMIDE may react with strong oxidizing agents and strong acids (NTP, 1992). Susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Hexamethylphosphoramide in the storage compatibility matrix →
10 · Questions
Hexamethylphosphoramide — frequently asked questions
What is the CAS number of Hexamethylphosphoramide?
The CAS number of Hexamethylphosphoramide is 680-31-9. Its EC number is 211-653-8.
What is the chemical formula of Hexamethylphosphoramide?
The molecular formula of Hexamethylphosphoramide is C6H18N3OP and its molecular weight is 179.2 g/mol.
What does a Hexamethylphosphoramide label have to show?
Under CLP Annex VI the label for Hexamethylphosphoramide carries the pictogram Health hazard and the signal word is Danger.
Is Hexamethylphosphoramide flammable?
CLP Annex VI assigns Hexamethylphosphoramide 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 104.44 °C (220 °F) (NIOSH).
Is Hexamethylphosphoramide a carcinogen?
Yes. CLP Annex VI classifies Hexamethylphosphoramide as a category 1A or 1B carcinogen and assigns it H350: may cause cancer. IARC places it in Group 2B: possibly carcinogenic to humans.
What is the exposure limit for Hexamethylphosphoramide?
The US occupational exposure limit reported for Hexamethylphosphoramide 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 Hexamethylphosphoramide?
The boiling point reported for Hexamethylphosphoramide is 233 °C (451.4 °F), at 760 mmHg (HSDB).
What is the melting point of Hexamethylphosphoramide?
The melting point reported for Hexamethylphosphoramide is 6.11 °C (43 °F) (NIOSH).
How should Hexamethylphosphoramide be stored?
PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/ (Hazardous Substances Data Bank (HSDB))
Nearby
Substances next to Hexamethylphosphoramide
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