Common Name(s): Ethyl estradiolcarboxylate,ethyl estradiolcarboxylate,prohibited hormone,pharmaceutical estrogen — not cosmetic
CAS Number: N/a
DESCRIPTION
What It Does: Prohibited in eu cosmetics. steroidal estrogen hormones are pharmaceutical drugs whose primary pharmacological mechanism (erα/erβ agonism with systemic hormonal activity) is incompatible with cosmetic classification.
Why It's Used: Eu cosmetics regulation defines a cosmetic as a substance applied for the purpose of cleansing, perfuming, or altering appearance — not for the purpose of pharmacological hormonal activity. estrogens' primary mechanism is hormonal, not cosmetic.
How It Works: Ethinylestradiol and estradiol bind erα and erβ with high affinity (kd ~0.1 nm) → genomic estrogen receptor signalling → reproductive and systemic hormonal effects that constitute primary pharmacological activity, not cosmetic effect on appearance.
Typically Found In: Prohibited in cosmetics
TECHNICAL DETAILS
Primary Category: Active ingredient – cosmetic active
Secondary Functions: Skin conditioning
Application Areas:
Facial Skincare
Body Care
Hair Care
Beard Care
Color Cosmetics (Makeup)
Dietary/Oral Supplements
Typical Concentration Range: Prohibited
SOURCING & ETHICS
Vegan Status: Conditional - supplier confirmation required
Halal Status: Unverified - supplier confirmation required
Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier. [audit 2026-07-29 rev2: the record's own source_notes does not assert a non-animal origin, or instructs the reader to verify with the supplier; "yes" asserts knowledge the record does not hold. determination requires shariah-panel sign-off.]
SKIN COMPATIBILITY
Irritancy Rating: 1/5 – very low
Comedogenicity Rating: 0/5 – non-comedogenic
Sensitivity Concerns: Well-tolerated by most skin types.
Safe for Sensitive Skin: Yes
SAFETY & COMPATIBILITY
Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.
Works Well With: Standard skincare actives
Avoid Combining With: No known significant incompatibilities
SCIENTIFIC NOTE
Non-hormonal alternatives for skin estrogen-like effects: phytoestrogens (genistein, daidzein) provide erβ-selective activity at 1000× lower affinity — well within the cosmetic/drug boundary; these are the appropriate cosmetic alternatives.
Last Verified: 2026-03-22
Primary Sources: Eu regulation 1223/2009 annex ii,ethyl estradiolcarboxylate hormone prohibition review