Aspartic Acid
Also known as Aspartic Acid, L-Aspartic Acid, 2-Aminosuccinic acid
“CIR Expert Panel says: safe as used in cosmetics.”
Aspartic Acid (CAS 56-84-8; L-form; dicarboxylic α-amino acid, C4H7NO4) is used in cosmetics as a low-molecular-weight humectant and NMF component. The CIR Expert Panel group assessment of all 21 proteinogenic α-amino acids (Burnett et al., IJT 32(S4):41-64, 2013; PMID 24335967) names Aspartic Acid in the conclusion as safe in the present practices of use and concentration in cosmetic formulations, supported by dermal and ocular irritation/sensitization data. The QRT (Sept 2022) records Finding=S (Safe) with no qualifying conditions.
Proteinogenic α-amino acid (L-form): endogenous constituent of skin's natural moisturizing factor (NMF); dicarboxylic side chain enables strong hydrogen-bonding with water molecules
Humectant and skin-conditioning agent: attracts and retains moisture in the stratum corneum
CIR Expert Panel concluded Aspartic Acid is safe as used in cosmetics in the present practices of use and concentration:41-64, 2013; QRT Finding=S, no conditions)
Participates in the urea cycle and transamination pathways; endogenous presence in skin supports tolerability profile
CIR Quick Reference Table (September 2022) — Aspartic Acid row: Finding=S, Citation=IJT 32(Suppl. 4):41-64, 2013
“Aspartic Acid | S | | IJT 32(Suppl. 4):41-64, 2013”— QuickReferenceTable_AllConclusionTypes.pdf, p. 38