Ceramide Eop
Also known as Ceramide 1, Ceramide 1A, CER[EOP], omega-O-acylceramide (phytosphingosine)
“CIR Expert Panel says: safe as used in cosmetics.”
Ceramide EOP (formerly Ceramide 1 / Ceramide 1A; CAS 627881-96-3) is a long-chain omega-O-acylceramide built on a phytosphingosine backbone, one of the structurally essential lipids of the stratum corneum. The CIR Expert Panel concluded ceramides — including Ceramide EOP by name — are safe as used in cosmetics, provided they are not derived from bovine central nervous system tissue (Burnett et al. 2020, IJT 39(3_suppl):5S-25S). Biophysical research confirms CER[EOP] forms the long-periodicity phase critical to skin barrier integrity even in the dry state (Kessner et al. 2010, Chem Phys Lipids). Vyumvuhore et al. (2018, Int J Cosmet Sci) found EOP sub-class ceramides are significantly depleted in xerotic skin, supporting its role as a skin-barrier-relevant cosmetic active. Rawlings et al. (2022) directly measured CER EOP levels in human stratum corneum across ethnic groups, finding elevated EOP levels associated with altered barrier behaviour in Albino African subjects.
Endogenous stratum corneum lipid — one of three principal ceramide sub-classes (EOP, NS, NdS) that decline significantly in xerosis (Vyumvuhore et al. 2018)
Forms the long-periodicity lamellar phase essential to skin barrier function; CER[EOP] achieves this in dry state without hydration requirement (Kessner et al. 2010)
Approved safe as used by the CIR Expert Panel across cosmetic product types (CIR Final Report 03/2015; Burnett et al. 2020)
Formerly labelled Ceramide 1 / Ceramide 1A; INCI modernised to Ceramide EOP in 2014 — well-established safety record under legacy nomenclature
CIR safety conclusion is conditioned on ingredient not being derived from bovine central nervous system tissue (BSE risk); synthetically produced or plant-derived forms are not subject to this concern
Elevated omega-O-acylceramide levels (including EOP) may be associated with altered barrier behaviour in some populations, though this reflects endogenous dysregulation rather than cosmetic safety risk (Rawlings et al. 2022)
CIR Quick Reference Table (12/2017, revised 07/2018) — Ceramide EOP row: Finding=S, Citation=Final report 03/2015 available from CIR
“Ceramide EOP | S | | Final report 03/2015 available from CIR”— QRT-122017revised072018.pdf, p. 22