Pca
Also known as Pyrrolidone Carboxylic Acid, Pyroglutamic Acid, Pidolic Acid, 2-Pyrrolidone-5-Carboxylic Acid, L-PCA
“CIR Expert Panel says: safe as used in cosmetics.”
The CIR Expert Panel (2019, IJT 38(S2):5S-11S) reassessed PCA (the free acid) and its salts together, confirming they are safe in cosmetics at present practices of use and concentration, provided they are not used in formulations where N-nitroso compounds can form. PCA is the second most abundant component of the skin's natural moisturizing factor (NMF), derived from filaggrin proteolysis; stratum corneum PCA levels track filaggrin genotype and serve as a validated biomarker. As a humectant, formulations containing at least 2% PCA in an appropriate vehicle improve dry skin conditions.
Major component of the skin's natural moisturizing factor (NMF); second most abundant NMF constituent at ~12% of total
Highly hygroscopic humectant derived endogenously from filaggrin proteolysis in the stratum corneum
Effective skin conditioning agent; formulations with >=2% PCA in appropriate vehicles improve dry skin
Nonirritating and nonsensitizing at cosmetic use concentrations per CIR assessment
Stratum corneum PCA levels are a validated biomarker of filaggrin gene status
- · Should not be incorporated into formulations where N-nitroso compound formation is possible
CIR Quick Reference Table (12/2017, revised 07/2018) — PCA row: Finding=SQ, Citation=IJT 18(S2):25-34, 1999; Final report 12/2014 availab…
“PCA SQ safe as used; should not be used in cosmetic products in which N-nitroso compounds can be formed IJT 18(S2):25-34, 1999; Final report 12/2014 available from CIR”— QRT-122017revised072018.pdf, p. 82