Is L-Isoleucine safe in cosmetics?
L-Isoleucine has a safety rating of "EXCELLENT" in our database. EU status: permitted. US status: permitted.
Excellent
Cosmetic Ingredient
L-Isoleucine
Also known as: Pentanoic acid, 2-amino-3-methyl-, (2S,3S)-, NSC 46708, Acetic acid, amino-sec-butyl-, Acetic acid, amino(1-methylpropyl)-, (R*,R*)-, (S-(R*,R*))-2-Amino-3-methylpentanoic acid (+14 more)
INCI: ISOLEUCINE
L-Isoleucine (CAS 73-32-5) is a cosmetic cosmetic ingredient functioning as Antistatic, Hair Conditioning, 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 industrial chemical safety and pharmaceutical data.
View industrial chemical safety profile for CAS 73-32-5 →
Auto-generated CPSR Part A draft with source citations
Function
Antistatic, Hair Conditioning, Skin Conditioning
Safety Rating
EXCELLENT
Chemistry & Identifiers
IUPAC Name
(2S,3S)-2-amino-3-methylpentanoic acid
InChIKey
AGPKZVBTJJNPAG-WHFBIAKZSA-N
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
GRAS per 21 CFR 172.320; no FDA cosmetic restrictions
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-Isoleucine.
Calculate MoS for your specific formulation with the MoS Calculator.
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
10 - 100 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No
Additional Ingredient Properties
2 property records from structured ingredient metadata.
acne
{"cas_number": "73-32-5", "anti_acne_mechanism": "anti_inflammatory", "comedogenicity_rating_0_to_5": "0", "acne_type_efficacy": "inflammatory", "sebum_reduction_pct_clinical": "0-5", "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_ac…
anti_aging
{"anti_aging_claim": "barrier-repair", "mechanism_of_action": "Building block for proteins, NMF component", "target_skin_layer": "epidermis", "collagen_stimulation": "Mild", "elastin_protection": "Mild", "wrinkle_reduction_pct": "4-8", "clinical_study_duration_weeks": "8", "sample_size": "25", "double_blind": "No", "placebo_controlled": "Yes", "published_journal": "Int J Cosmet Sci", "improvement_…
PubChem Annotations
Safety and regulatory annotations from PubChem (NCBI) aggregated sources.
Regulatory (2)
JECFA Number
2118
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
JECFA Evaluation
L-ISOLEUCINE | 2012 | No safety concern at current levels of intake when used as a flavouring agent | TRS 974-JECFA 76 | FAS 67 JECFA 76
Source: Joint FAO/WHO Expert Committee on Food Additives (JECFA)
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Flavouring and nutrient
Regulatory List Membership (1)
FDA Substances Added to Food (EAFUS)
Expert Verdict
Expert safety assessment and concern-level summary for L-Isoleucine.
Regulatory Flags
fda_food_additive
jecfa_safe
Known Synonyms
Pentanoic acid, 2-amino-3-methyl-, (2S,3S)-
NSC 46708
Acetic acid, amino-sec-butyl-
Acetic acid, amino(1-methylpropyl)-, (R*,R*)-
(S-(R*,R*))-2-Amino-3-methylpentanoic acid
2-Amino-3-methylpentanoic acid, (S-(R*,R*))-
EINECS 200-798-2
Norvaline, 3-methyl-
Pentanoic acid, 2-amino-3-methyl-
Pentanoic acid, 2-amino-3-methyl-, (S-(R*,R))-
Valeric acid, 2-amino-3-methyl-
Isoleucina
Isoleucinum
UNII-04Y7590D77
(2S,3S)-2-Amino-3-methylpentanoate
(2S,3S)-2-amino-3-methyl-Pentanoate
(2S,3S)-2-amino-3-methyl-pentanoic acid
(2S,3S)-a-Amino-b-methyl-N-valerate
(2S,3S)-a-Amino-b-methyl-N-valeric acid
Chemical Function
Flavouring and nutrient
Regulatory Lists
pharmaceutical
active_ingredient; Australia
food_additive; Substances Added to Food (formerly EAFUS) (2/2019)
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
ISOLEUCINE
ChEMBL ID
CHEMBL1233584
Max Phase
2
Adverse Event Associations
3
Frequently Asked Questions
Is L-Isoleucine allowed in the EU?
L-Isoleucine EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does L-Isoleucine do in cosmetics?
L-Isoleucine functions as: Antistatic, Hair Conditioning, Skin Conditioning. It is classified as a cosmetic ingredient in our database. CAS number: 73-32-5.
Is L-Isoleucine used outside cosmetics?
L-Isoleucine 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.
Compliance Tools
Check L-Isoleucine compliance across multiple jurisdictions:
Ingredient Decoder
Paste a full ingredient list for instant analysis
82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
Check compliance across multiple jurisdictions
MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
Compare limits across jurisdictions
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