Ethinylestradiol

Also known as: EE, EE2, Ethinyl estradiol, 19-​Norpregna-​1,​3,​5(10)​-​trien-​20-​yne-​3,​17-​diol, (17α)​-, 19-Norpregna-1,3,5(10)-trien-20-yne-3,17-diol, (17.alpha.)- (+15 more)

INCI: ETHINYLESTRADIOL

Ethinylestradiol (CAS 57-63-6) is a cosmetic cosmetic ingredient functioning as Synthetic estrogen (hormonal agent) — pharmaceutical, NOT a cosmetic function. EU Regulation 1223/2009 status: prohibited. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.

View industrial chemical safety profile for CAS 57-63-6 →

Auto-generated CPSR Part A draft with source citations
Function
Synthetic estrogen (hormonal agent) — pharmaceutical, NOT a cosmetic function
Safety Rating
POOR

Chemistry & Identifiers

Formula
C20H24O2
MW
296.4 g/mol
PubChem CID
5991
IUPAC Name
(8R,9S,13S,14S,17R)-17-ethynyl-13-methyl-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthrene-3,17-diol
InChIKey
BFPYWIDHMRZLRN-SLHNCBLASA-N

Regulatory Status

EU EU Status prohibited
US US Status prohibited
US Notes PROHIBITED — FDA considers hormone-containing cosmetics as adulterated drug products under the FD&C Act; ethinylestradiol is a prescription drug substance

For full compliance data across multiple jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety, dermal absorption, and sensitization profile summaries for Ethinylestradiol.

Calculate MoS for your specific formulation with the MoS Calculator.

Expanded Jurisdictional Detail

Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.

JPKR Japan/Korea Cosmetics
Japan (Restricted): max N/A (IU limit)
Additional Jurisdictional Restrictions (3)
Jurisdiction Status Max % Product Type
CN banned - -
CA banned - -
KR prohibited - -

PubChem Annotations

Safety and regulatory annotations from PubChem (NCBI) aggregated sources.

Safety (5)
Carcinogen Classification
No indication of carcinogenicity to humans (not listed by IARC).
Source: Toxin and Toxin Target Database (T3DB)
Carcinogen Classification
Ethinyl Estradiol | TR-548: Toxicology and Carcinogenesis Studies of Ethinyl Estradiol (CASRN 57-63-6) in Sprague-Dawley Rats (Feed Studies) (2010 ) | 05/16/07 | Equivocal Evidence | Equivocal Evidence | Under the conditions of this 2-year feed study with continuous exposure to the test compound from conception through termination (F1C), there was no evidence of carcinogenic activity of ethin
Source: NTP Technical Reports
Carcinogen Classification
Ethinyl Estradiol (Multigenerational) | TR-547: Multigenerational Reproductive Toxicology Study of Ethinyl Estradiol (CASRN 57-63-6) in Sprague-Dawley Rats (Feed Studies) (2010 ) | 05/16/07 | Ethinyl estradiol administered at exposure concentrations of 2, 10, or 50 ppb in a low phytoestrogen diet to NCTR CD (Sprague-Dawley) rats showed clear biological activity including potentially adverse effec
Source: NTP Technical Reports
Evidence for Carcinogenicity
Evaluation: There is sufficient evidence in humans for the carcinogenicity of post-menopausal estrogen therapy. There is sufficient evidence in experimental animals for the carcinogenicity of estradiol and estrone. There is limited evidence in experimental animals for the carcinogenicity of conjugated equine estrogens, equilin and estriol. There is inadequate evidence in experimental animals for t
Source: Hazardous Substances Data Bank (HSDB)
Endocrine Disruptors
Potential endocrine disrupting compound
Source: NORMAN Suspect List Exchange

Function Categories & List Membership

Cosmetic/Chemical Function Categories
Softener and conditioner
Regulatory List Membership (1)
California Proposition 65 (OEHHA)

Expert Verdict

Expert safety assessment and concern-level summary for Ethinylestradiol.

Regulatory Flags

prop65

Known Synonyms

EE EE2 Ethinyl estradiol 19-​Norpregna-​1,​3,​5(10)​-​trien-​20-​yne-​3,​17-​diol, (17α)​- 19-Norpregna-1,3,5(10)-trien-20-yne-3,17-diol, (17.alpha.)- 19-Norpregna-1,3,5(10)-trien-20-yne-3,17-diol, (17alpha)- Aethinyloestradiolum Amenorone BRN 2419975 3,17beta-Dihydroxy-17alpha-ethynyl-1,3,5(10)-estratriene 3,17-beta-Dihydroxy-17-alpha-ethynyl-1,3,5(10)-estratriene 3,17beta-Dihydroxy-17alpha-ethynyl-1,3,5(10)-oestratriene 3,17-beta-Dihydroxy-17-alpha-ethynyl-1,3,5(10)-oestratriene EINECS 200-342-2 Estra-1,3,5(10)-triene-3,17beta-diol, 17alpha-ethynyl- Estra-1,3,5(10)-triene-3,17-beta-diol, 17-alpha-ethynyl- 17-alpha-Ethinyl-3,17-dihydroxy-delta(sup 1,3,5)-estratriene 17alpha-Ethinyl-3,17-dihydroxy-delta(sup1,3,5)-estratriene 17alpha-ethinyl-3,17-dihydroxy-delta(sup1,3,5)oestratriene 17alpha-Ethinylestradiol-17beta

Chemical Function

Softener and conditioner

Regulatory Lists

detected; drinking_water; MN Chemical Screening OEHHA Proposition 65 (1/2023) Canada; Personal care; Substances in PCP - Canada (4/2014) pharmaceutical active_ingredient; Europe; Pesticides OEHHA Proposition 65 (3/2019) Canada; pharmaceutical OEHHA Proposition 65 (1/2023) active_ingredient; Australia detected; MN Chemical Screening; wastewater detected; MN Chemical Screening; surface_water detected; MN Chemical Screening; wastewater detected; drinking_water; MN Chemical Screening detected; drinking_water; MN Chemical Screening detected; drinking_water; MN Chemical Screening

Cross-Vertical Safety Context

Same-CAS public records found in pharmaceutical data.

SOURCE ChEMBL / DrugCentral / FAERS DB_PHARMA CAS match

Pharmaceutical Data

Same-CAS rows from the pharmaceutical spoke database.

Compound
ETHINYL ESTRADIOL
ChEMBL ID
CHEMBL691
Max Phase
4
Adverse Event Associations
2055
View full pharmaceutical profile →

Frequently Asked Questions

Is Ethinylestradiol safe in cosmetics?

Ethinylestradiol has a safety rating of "POOR" in our database. EU status: prohibited. US status: prohibited.

Is Ethinylestradiol allowed in the EU?

Ethinylestradiol EU regulatory status: prohibited. This is based on EU Regulation 1223/2009 and its amendments.

What does Ethinylestradiol do in cosmetics?

Ethinylestradiol functions as: Synthetic estrogen (hormonal agent) — pharmaceutical, NOT a cosmetic function. It is classified as a cosmetic ingredient in our database. CAS number: 57-63-6.

Is Ethinylestradiol used outside cosmetics?

Ethinylestradiol also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.

Does Ethinylestradiol have different safety status in cosmetics vs industrial chemicals?

Ethinylestradiol is prohibited in EU cosmetics but has active industrial GHS classifications (H302, H350, H360, H372, H410).

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