Benzyl Benzoate
Also known as Benzyl benzoate, Benzoic acid, phenylmethyl ester, Phenylmethyl benzoate, Ascabin, Ascabiol
“EU SCCS says: restricted.”
Benzyl benzoate is a multi-functional aromatic ester (benzyl ester of benzoic acid) used in cosmetics as a fragrance ingredient, fragrance fixative, plasticizer, and solvent. The 2017 CIR Expert Panel amended safety assessment (Johnson et al., IJT 36(Suppl. 3):5S-30S, PMID 29243541) grouped Benzyl Benzoate with Benzyl Alcohol and Benzoic Acid/its Salts and concluded all are 'safe in the present practices of use and concentration described in this safety assessment' — yielding an unqualified 'S' Finding in the CIR Quick Reference Table. SCCS/1459/11 Table 13-1 classifies Benzyl Benzoate as an established contact allergen in humans (rating ++; the asterisk indicates it is one of the original 1999 SCCNFP-listed 26 allergens). Under EU Regulation 1223/2009 it is listed in Annex III (Entry 85) as a regulated fragrance allergen requiring label declaration when present above 0.001% in leave-on products or 0.01% in rinse-off products. The RIFM 2020 safety assessment (Api AM et al., FCT 144 Suppl 1:111500, PMID 32615241) classified it as a weak sensitizer with a No Expected Sensitization Induction Level (NESIL) of 59,000 µg/cm²; murine LLNA results were vehicle-dependent (non-sensitizing in one vehicle, EC3 17% in another); human maximization testing produced no sensitization reactions. The cosmetic-vs-pharmaceutical dose distinction is large: topical scabicide formulations use 10–25% benzyl benzoate (a not-FDA-approved-in-US drug use; WHO Essential Medicines list) — ~2,500× to 25,000× the EU rinse-off cosmetic disclosure threshold. The cosmetic regulatory framework governs only the fragrance/fixative use case at typical concentrations well below the pharmaceutical use range.
CIR 2017 amended assessment concluded unqualified 'safe in the present practices of use and concentration' — stronger CIR finding than many other Annex III fragrance allergens which receive SQ qualifications
Multi-functional in cosmetics: serves as fragrance ingredient, fragrance fixative (slows volatile evaporation), solvent for fragrance components, and occasional plasticizer — allowing formulators to use one ingredient across multiple roles
WHO Essential Medicines list entry (in scabicide/pediculicide contexts; not US-FDA-approved for medical use) attests to a long-established human safety record at much higher concentrations than any cosmetic exposure
Naturally occurring in many balsams (Peru balsam, Tolu balsam) and essential oils, providing a sweet-balsamic odor note used in floral fragrance compositions
Established EU fragrance allergen (Annex III Entry 85, SCCS/1459/11 Table 13-1, human evidence rating ++): label declaration required above 0.001% leave-on / 0.01% rinse-off due to documented sensitization potential
RIFM 2020 characterized benzyl benzoate as a weak sensitizer (NESIL 59,000 µg/cm²) with vehicle-dependent murine LLNA outcomes — sensitization potential is real but lower than many other Annex III allergens
Pharmaceutical-vs-cosmetic dose gap is extreme: topical scabicide use is at 10–25% (ex-US prescription drug; not FDA-approved as a US drug product), while EU cosmetic labeling threshold for the fragrance use case is 0.001% leave-on. The CIR/SCCS cosmetic safety assessments do not cover the pharmaceutical 25% topical use; that exposure is governed by drug regulation in jurisdictions where it is approved
Multi-functional ingredient: when used as a plasticizer or fragrance fixative (rather than as a fragrance note in itself), the EU labeling obligation still applies if the substance is present above the Annex III threshold — the obligation is concentration-based, not function-based
Reg (EU) 2023/1545 expanded the Annex III fragrance allergen list to >80 substances (transition for new products through July 2028); Benzyl Benzoate was already in the original 26-allergen list and its labeling rule is unchanged
CIR Quick Reference Table (12/2017, revised 07/2018) — Benzyl Benzoate row: Finding=S (Safe), Citation=IJT 36(Suppl. 3):5-30, 2017
“Benzyl Benzoate | S | | IJT 36(Suppl. 3):5-30, 2017”— QRT-122017revised072018.pdf, Benzyl Benzoate row (B section, p. 12)
Safety Assessment of Benzyl Alcohol, Benzoic Acid and its Salts, and Benzyl Benzoate (Johnson W et al., Int J Toxicol 36(3_suppl):5S-30S,…
SCCS/1459/11 — Opinion on fragrance allergens in cosmetic products (adopted 26-27 June 2012); Table 13-1 (Established contact allergens i…
“BENZYL BENZOATE* | 120-51-4 | ++”— sccs_o_102_0.pdf, Table 13-1 (Established contact allergens in humans, Individual chemicals), p. 106
EU Regulation 1223/2009 Annex III (Restricted Substances) — Entry 85: Benzyl Benzoate, CAS 120-51-4, EC 204-402-9; fragrance allergen lab…
“Entry 85, Benzyl Benzoate, CAS 120-51-4, EC 204-402-9; The presence of the substance must be indicated in the list of ingredients referred to in Article 19(1)(g) when its concentration exceeds: 0.001 % in leave-on products, 0.01 % in rinse-off products”— EU Reg 1223/2009 Annex III, Entry 85