Ingredient Dictionary

PHENYL METHYL PYRAZOLONE

Edaravone is a pyrazolone that is 2,4-dihydro-3H-pyrazol-3-one which is substituted at positions 2 and 5 by phenyl and methyl groups, respectively.

Definition

Edaravone is a pyrazolone that is 2,4-dihydro-3H-pyrazol-3-one which is substituted at positions 2 and 5 by phenyl and methyl groups, respectively. It has a role as an antioxidant and a radical scavenger.

Source: PubChem

US FDA substance register · UNII S798V6YJRP · registered name Edaravone · single chemical substance

Source: US FDA Unique Ingredient Identifier (UNII)

Cosmetic roles

Dyes hairHAIR DYEING

Safety & regulatory references

Banned: South Korea
Restricted: Taiwan · United Kingdom

Source: MFDS (Korea) cosmetic regulatory information · ASEAN Cosmetic Directive · EU Cosmetics Regulation · Taiwan FDA cosmetic ingredients · Taiwan FDA cosmetic regulations · UK cosmetics regulations (OPSS)

ASEAN

Field of application and/or use : Hair dye substance in oxidative hair dye products. Use for dyeing eyelashes and eyebrows is not permitted.
Other limitations and requirements : After mixing under oxidative conditions the maximum concentration applied to hair must not exceed 0.25 % The direction for use “wear suitable gloves” must be included in label or leaflet text.
Conditions of use and warning which must be printed on the labels : The mixing ratio must be printed on the label. Hair colorants can cause severe allergic reactions. Read and follow instructions. This product is not intended for use on persons under the age of 16. Temporary “black henna” tattoos may increase your risk of allergy. Do not colour your hair if: • you have a rash on your face or sensitive, irritated and damaged scalp, • you have ever experienced any reaction after colouring your hair, • you have experienced a reaction to a temporary “black henna” tattoo in the past Do not use to dye eyelashes or eyebrows

China

Maximum concentration : 0.25%

European Union

Product Type, body parts : Hair dye subtance in oxidative hair dye products
Other : After mixing under oxidative conditions the maximum concentration applied to hair must not exceed 0.25%.
Wording of conditions of use and warnings : To be printed on the label: The mixing ratio. “ Hair colourants can cause severe allergic reactions. Read and follow instructions. This product is not intended for use on persons under the age of 16. Temporary ‘black henna’ tattoos may increase your risk of allergy. Do not colour your hair if: — you have a rash on your face or sensitive, irritated and damaged scalp, — you have ever experienced any reaction after colouring your hair, — you have experienced a reaction to a temporary ‘black henna’ tattoo in the past.

Source: MFDS (Korea) cosmetic regulatory information

Not classified under Korea’s toxic-substance GHS list · existing chemical substance

Source: Korea toxic substances GHS register (NIER)

EU Cosmetics Regulation, Annex III (restricted substances), entry 228 · applies to Hair dye subtance in oxidative hair dye products

Source: EU restricted substances (Annex III)

Restriction III/228 · SCCS opinion: Opinion on Phenyl methyl pyrazolone

Source: EU CosIng ingredient list

Reviewed by CIR: Annual Review of Cosmetic Ingredient Safety Assessments: 2007-2010

Source: US Cosmetic Ingredient Review (CIR)

Reviewed by CIR: Final Report on the Safety Assessment of Phenyl Methyl Pyrazolone

Source: US Cosmetic Ingredient Review (CIR)

More data — names, identifiers, properties, test records, literature

Names & identifiers

PHENYL METHYL PYRAZOLONEINCI페닐메틸피라졸론Korean label name (MFDS standard)3H-Pyrazol-3-one, 2,4-dihydro-5-methyl-2-phenyl-Synonym

CAS No.chemical registry number: 89-25-8
EC No.EU chemical inventory number: 201-891-0
DTXSIDUS EPA chemical ID: DTXSID9021130
DTXCIDUS EPA compound ID: DTXCID201130

IUPAC: 5-Methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one
Molecular formula: C10H10N2O
Molecular weight: 174.203 g/mol

Measured properties

Appearance: 1-phenyl-3-methyl-5-pyrazolone appears as white to off-white powder or crystals. (NTP, 1992) · White solid, [Merck Index] Light yellow odorless powder, [Alfa Aesar MSDS]
Boiling point: 549 °F at 105 mmHg (NTP, 1992) · 287
Melting point: 261 to 266 °F (NTP, 1992) · 129.7
Solubility: less than 1 mg/mL at 73 °F (NTP, 1992) · SOL IN HOT WATER & HOT ALCOHOL, SLIGHTLY SOL IN BENZENE, INSOL IN PETROLEUM ETHER
Dissociation constant: 7.0
Colour: white
pH: 4 (4 - 4.4)
Melting/freezing point: 129 ℃
Initial boiling point and range: 191 ℃(@ 17 mmHg)
Flash point: 155 ℃
Flammability (solid, gas): flammable
Vapour pressure: 0.01 ㎜Hg
Water solubility: 3300 ㎎/ℓ (at 20℃)
Vapour density: 6.01
Relative density: 1.12 (at 20℃)
n-Octanol/water partition coefficient (Kow): 2.56 (est.)
Auto-ignition temperature: 490 ℃ (at 20℃)
Molecular weight: 174.2

Values measured on the substance itself. The KOSHA data are a reference for writing and reviewing safety data sheets, not a specification for a commercial raw material.

Source: PubChem · KOSHA safety data sheets (Korea)

What products actually use it for

What the 3 products reported to the US EPA with this ingredient use it for. Products outside cosmetics are included, so the top few rows are its main uses.

Dye3

Source: US EPA CompTox dashboard

Irritation and sensitisation studies

5 skin studies and 4 eye studies are on record.

Classed as moderate2Classed as low2

The studies disagree (the most common conclusion covers 50%), so they do not establish that this ingredient is irritating. These tests are on the raw material itself; irritation at the amount in a finished product is a different question.

See all 9 studies

Low to Moderate Frequency of Sensitization
skin sensitisation: in vivo (LLNA) · Screening · according to OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Studies Indicate No Significant Irritation
skin irritation: in vivo · Screening · OECD Guideline 404 (Acute Dermal Irritation / Corrosion) The identity of the test substance was not sufficiently documented. Only a summary test report was available, there was no raw data. However, the study was conducted under FDA test protocols. Appropriate dose level was used. The scoring system deviated slighty from the current OECD protocol. Control analysis was performed. Restriction for reliability was due to the age of the study (1980). equivalent or similar to
Not likely to be sensitizing
skin sensitisation: in vivo (non-LLNA) · Screening · according to OECD Guideline 406 (Skin Sensitisation) Adopted : 17 July 1992, Buehler test (3 applications)
Low to Moderate Frequency of Sensitization
skin sensitisation: in vivo (LLNA) · Screening · according to OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay) Adopted : 24th April 2002
Ambiguous
skin irritation: in vivo · Screening · OECD Guideline 404 (Acute Dermal Irritation / Corrosion) 12 May 1981 according to
Studies Indicate No Significant Irritation
eye irritation: in vivo · Screening · OECD Guideline 405 (Acute Eye Irritation / Corrosion) according to
Ambiguous
eye irritation: in vitro / ex vivo · Screening · other guideline: Journal Officiel de la Republique Francaise (JORF) No. 300, 28 November 1996, page 19137 REACh regulation recommends ECVAM protocols DB-ALM No. 47, January 1992 and DB-ALM No. 96, July 1994. equivalent or similar to
Ambiguous
eye irritation: in vivo · Screening · OECD Guideline 405 (Acute Eye Irritation / Corrosion) according to
Studies Indicate No Significant Irritation
eye irritation: in vivo · Screening · OECD Guideline 405 (Acute Eye Irritation / Corrosion) Dated February 24th 1987 equivalent or similar to