Is L-Ergothioneine safe in cosmetics?
L-Ergothioneine has a safety rating of "EXCELLENT" in our database. EU status: permitted. US status: permitted.
Excellent
Cosmetic Ingredient
L-Ergothioneine
Also known as: (S)-(1-Carboxy-2-(2-mercaptoimidazol-4-yl)ethyl)trimethylammonium hydroxide List Acronyms, 1H-Imidazole-4-ethanaminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, hydroxide, inner salt, 1H-Imidazole-4-ethanaminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, inner salt, (alphaS)-, 1H-Imidazole-4-ethanaminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, inner salt, (S)-, 1H-Imidazole-4-ethaniminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, hydroxide, inner salt, (S)- (+1 more)
INCI: ERGOTHIONEINE
L-Ergothioneine (CAS 497-30-3) is a cosmetic cosmetic ingredient functioning as Antioxidant, Skin conditioning. EU Regulation 1223/2009 status: permitted. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in pharmaceutical data.
View industrial chemical safety profile for CAS 497-30-3 →
Auto-generated CPSR Part A draft with source citations
Function
Antioxidant, Skin conditioning
Safety Rating
EXCELLENT
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
GRAS status evaluated by FDA; no cosmetic-specific restrictions; widely used in premium skincare
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for L-Ergothioneine.
Calculate MoS for your specific formulation with the MoS Calculator.
Additional Ingredient Properties
10 property records from structured ingredient metadata.
acne
{"cas_number": "497-30-3", "anti_acne_mechanism": "anti_inflammatory", "comedogenicity_rating_0_to_5": "0", "acne_type_efficacy": "inflammatory", "sebum_reduction_pct_clinical": "0-10", "prescription_required_usa": "No", "otc_drug_monograph_category": "No", "max_otc_concentration_pct": "No limit", "japan_quasi_drug_anti_acne": "No", "korea_functional_cosmetic_acne": "No", "eu_cosmetic_restriction_…
anti_aging
{"anti_aging_claim": "antioxidant-protection, anti-inflammatory", "mechanism_of_action": "Cofactor for enzymatic reactions, antioxidant activity", "target_skin_layer": "epidermis", "collagen_stimulation": "Mild", "elastin_protection": "Mild", "wrinkle_reduction_pct": "10-18", "clinical_study_duration_weeks": "12", "sample_size": "30", "double_blind": "Yes", "placebo_controlled": "Yes", "published_…
anti_pollution
{"cas_number": "497-30-3", "ingredient_class": "antioxidant_pollution_shield", "primary_mechanism": "free_radical_scavenging", "pollution_types_targeted": "PM2_5/UV_A", "IR_A_protection": "no", "visible_light_protection": "no", "digital_screen_protection_claim": "no", "PAH_neutralization": "no", "ozone_protection": "no", "mitochondrial_protection": "no", "Nrf2_activation": "no", "AhR_pathway_modul…
antioxidant
{"cas_number": "497-30-3", "antioxidant_class": "thiol", "chemical_subclass": "thioimidazole betaine", "molecular_weight_daltons": "229.3", "orac_value_umol_te_per_g": "2800", "dpph_radical_scavenging_ic50_ug_per_ml": "8-15", "abts_trolox_equivalent": "1.3", "singlet_oxygen_quenching": "very high", "superoxide_dismutase_mimetic": "yes", "hydroxyl_radical_scavenging": "very high", "lipid_peroxidati…
cost_pricing
{"cost_tier": "luxury", "estimated_cost_per_kg_usd_low": "2500", "estimated_cost_per_kg_usd_high": "4500", "natural_premium_markup_pct": "0", "organic_certified_premium_pct": "0", "supply_chain_volatility": "high", "primary_source_region": "France/Japan", "bulk_discount_threshold_kg": "0.5", "seasonal_price_variation": "high", "commodity_or_specialty": "specialty", "substitute_ingredients": "Gluta…
fermentation
{"cas_number": "proprietary", "ingredient_class": "precision_fermentation", "production_organism": "bacteria", "fermentation_type": "aerobic", "substrate_feedstock": "sugarcane, glucose, glycerol", "bioactive_compounds_produced": "ergothioneine antioxidant", "mechanism_of_action_skin": "varies by ingredient - antioxidant, hydration, barrier protection", "skin_benefit_primary": "antioxidant", "skin…
ph_stability
{"optimal_ph_min": "5.0", "optimal_ph_max": "7.0", "stable_ph_min": "4.5", "stable_ph_max": "7.5", "degrades_above_ph": "8.0", "degrades_below_ph": "4.0", "ph_dependent_function": "Amino acid antioxidant", "formulation_note": "Exceptionally stable", "source": "Formulation literature"}
self_tanning
{"cas_number": "497-30-3", "ingredient_class": "tan_extender", "tanning_mechanism": "other", "color_development_onset_hours": "0.0", "full_color_development_hours": "0", "color_duration_days": "0", "DHA_concentration_if_applicable_pct": "0", "erythrulose_concentration_pct": "0", "pH_dependent_color": "no", "formaldehyde_release_concern": "no", "formaldehyde_release_ppm": "0", "AGE_formation_concer…
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Antioxidant
Expert Verdict
Expert safety assessment and concern-level summary for L-Ergothioneine.
Regulatory Flags
antioxidant
amino-acid-derivative
anti-aging
mushroom-derived
skin-conditioning
brightening
OCTN-1-transporter
Known Synonyms
(S)-(1-Carboxy-2-(2-mercaptoimidazol-4-yl)ethyl)trimethylammonium hydroxide List Acronyms
1H-Imidazole-4-ethanaminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, hydroxide, inner salt
1H-Imidazole-4-ethanaminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, inner salt, (alphaS)-
1H-Imidazole-4-ethanaminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, inner salt, (S)-
1H-Imidazole-4-ethaniminium, alpha-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, hydroxide, inner salt, (S)-
Ammonium, (1-carboxy-2-(2-mercaptoimidazol-4-yl)ethyl)trimethyl-, hydroxide, inner salt, L-(+)-
Chemical Function
Antioxidant
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.
ChEMBL ID
CHEMBL5209630
Frequently Asked Questions
Is L-Ergothioneine allowed in the EU?
L-Ergothioneine EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does L-Ergothioneine do in cosmetics?
L-Ergothioneine functions as: Antioxidant, Skin conditioning. It is classified as a cosmetic ingredient in our database. CAS number: 497-30-3.
Is L-Ergothioneine used outside cosmetics?
L-Ergothioneine also appears in pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Compliance Tools
Check L-Ergothioneine compliance across multiple jurisdictions:
Ingredient Decoder
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Substance Compliance
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MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
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