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

Phenolphthalein

Phenolphthalein is white or yellowish-white minute, triclinic crystals, often twinned and is odorless.

CAS 77-09-8 C20H14O4 318.3 g/mol Danger

01 · Identification

What Phenolphthalein is

Phenolphthalein is white or yellowish-white minute, triclinic crystals, often twinned and is odorless. Its molecular formula is C20H14O4 and its molecular weight is 318.3 g/mol. It melts at 263 °C.

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

02 · Identifiers

Phenolphthalein identifiers and molecular data

Phenolphthalein CAS number and EC number

CAS number77-09-8
EC number201-004-7
Index number (CLP Annex VI)604-076-00-1

Phenolphthalein molecular formula and molecular weight

Molecular formulaC20H14O4
Molecular weight318.3 g/mol
Chemical class Carcinogens

03 · GHS classification

Phenolphthalein hazard classification

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

Phenolphthalein pictograms and signal word

Signal wordDanger

Phenolphthalein hazard class and category

GHS hazard classes Phenolphthalein falls into
Hazard class Category From code Pictogram
Germ cell mutagenicity GHS chapter 3.5 Category 2 H341 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.

Phenolphthalein hazard statements (H-codes)

Hazard statements assigned to Phenolphthalein
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H361f Suspected of damaging fertility.

This page lists only the codes assigned to Phenolphthalein. 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 Phenolphthalein

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 Phenolphthalein 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

Phenolphthalein precautionary statements

CLP Annex VI assigns 4 precautionary statements to Phenolphthalein. 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.

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

Phenolphthalein 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 фенолфталеин
Spanish español Fenolftaleína
Czech čeština fenolftalein
Danish dansk phenolphthalein
German Deutsch Phenolphthalein
Estonian eesti fenoolftaleiin
Greek ελληνικά φαινολοφθαλεΐνη
English English phenolphthalein
French français phénolphtaléine
Croatian hrvatski fenolftalein
Italian italiano fenolftaleina
Latvian latviešu fenolftaleīns
Lithuanian lietuvių fenolftaleinas
Hungarian magyar fenolftalein
Maltese Malti fenolftalein
Dutch Nederlands fenolftaleïne
Polish polski fenoloftaleina
Portuguese português fenolftaleína
Romanian română fenolftaleină
Slovak slovenčina fenolftaleín
Slovenian slovenščina fenolftalein
Finnish suomi fenoliftaleiini
Swedish svenska fenolftalein

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

Phenolphthalein GHS label elements

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

GHS08 Health hazard pictogram

Danger

Phenolphthalein

  • May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
  • Suspected of damaging fertility.
  • 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 Phenolphthalein in the GHS label constructor →

07 · Health hazards

Phenolphthalein health hazards and exposure limits

Phenolphthalein hazard summary

Reported health effects include itching rash after skin contact and purging and collapse after ingestion; [CAMEO] Dust may be irritating if inhaled, but probably not irritating to the skin; [CHEMINFO]

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

Phenolphthalein carcinogenicity classification

IARC classification Group 2B — Possibly carcinogenic to humans
IARC monographs Volume 76: (2000) Some Antiviral and Antineoplastic Drugs, and Other Pharmaceutical Agents

Under the conditions of these 2-year feed studies, there was clear evidence of carcinogenic activity of phenolphthalein in male F344/N rats based on markedly increased incidences of benign pheochromocytomas of the adrenal medulla and of renal tubule adenomas and adenomas or carcinomas (combined). There was some evidence of carcinogenic activity of phenolphthalein in female F344/N rats based on the increased incidences of benign pheochromocytomas of the adrenal medulla in the 12,000 ppm group and of benign or malignant pheochromocytomas (combined) in the 12,000 and 25,000 ppm groups. There was clear evidence of carcinogenic activity of phenolphthalein in male B6C3F1 mice based on increased incidences of histiocytic sarcomas and of malignant lymphomas of thymic origin. There was clear evidence of carcinogenic activity of phenolphthalein in female B6C3F1 mice based on increased incidences of histiocytic sarcomas, malignant lymphomas of all types, lymphomas of thymic origin, and benign sex-cord stromal tumors of the ovary.

Source: US National Toxicology Program · TR-465: Toxicology and Carcinogenesis Studies of Phenolphthalein (CASRN 77-09-8) in F344/N Rats and B6C3F1 Mice (Feed Studies) (1996 )

Evaluation: There is inadequate evidence in humans for the carcinogenicity of phenolphthalein. There is sufficient evidence in experimental animals for the carcinogenicity of phenolphthalein. Overall evaluation: Phenolphthalein is possibly carcinogenic to humans (Group 2B)

Source: Hazardous Substances Data Bank (HSDB)

Phenolphthalein: 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.

08 · Physical and chemical properties

Phenolphthalein 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.

Phenolphthalein melting point

Property Value Conditions Source
Melting point 262.5 °C (504.5 °F) HSDB
260 °C (500 °F) range, midpoint shown CAMEO

Phenolphthalein density

Property Value Conditions Source
Density 1.299 g/cm³ at 25 °C CAMEO
1.277 g/cm³ at 32 °C HSDB

Phenolphthalein solubility

Property Value Conditions Source
Solubility 1 g dissolves in 12 ml alcohol, in about 100 ml ether; sol in dil solutions of Alkali hydroxides and hot solutions of alkali carborates forming a red soln HSDB
In water, 400 mg/L @ room temperature HSDB

Phenolphthalein vapor pressure

Property Value Conditions Source
Vapor pressure 6.7e-13 mmHg at 25 °C HSDB

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

09 · Source notes

Further notes on Phenolphthalein

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.

Solubility

Insoluble in benzene and petroleum ether; slightly soluble in carbon disulfide; soluble in ethyl ether, chloroform, and toluene; very soluble in ethanol, acetone, and pyrene.

Source: HSDB

10 · Handling and storage

Phenolphthalein storage and handling

Phenolphthalein 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)

Phenolphthalein reactivity

PHENOLPHTHALEIN is incompatible with alkaloids. (NTP, 1992)

Source: CAMEO Chemicals

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

11 · Questions

Phenolphthalein — frequently asked questions

What is the CAS number of Phenolphthalein?

The CAS number of Phenolphthalein is 77-09-8. Its EC number is 201-004-7.

What is the chemical formula of Phenolphthalein?

The molecular formula of Phenolphthalein is C20H14O4 and its molecular weight is 318.3 g/mol.

What does a Phenolphthalein label have to show?

Under CLP Annex VI the label for Phenolphthalein carries the pictogram Health hazard and the signal word is Danger.

Is Phenolphthalein flammable?

CLP Annex VI assigns Phenolphthalein 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 Phenolphthalein a carcinogen?

Yes. CLP Annex VI classifies Phenolphthalein 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 melting point of Phenolphthalein?

The melting point reported for Phenolphthalein is 262.5 °C (504.5 °F) (HSDB).

How should Phenolphthalein 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))

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