Octocrylene
Also known as Octocrylene, 2-ethylhexyl 2-cyano-3,3-diphenylacrylate, Parsol 340, Uvinul N 539 T, Sunkem OTC
“EU SCCS says: restricted.”
Octocrylene (CAS 6197-30-4) is an organic UVB filter and photostabilizer for avobenzone, regulated in the EU at up to 10% under Annex VI entry 10. SCCS/1627/21 (Final Opinion, March 2021) concluded it is safe at 10% individually and in most combined product scenarios, but not safe at 10% or above in propellant spray when combined with other octocrylene-containing products (safe propellant spray limit is 9%). The SCCS flagged benzophenone — a suspected carcinogen formed through retro-aldol condensation — as a hazardous impurity and degradation product requiring monitoring and minimization. Peer-reviewed literature confirms benzophenone accumulates in octocrylene products over time (averaging 75 mg/kg post-aging; PMID 33682414), is detectable in raw OCT material and all tested OCT-containing consumer products (PMID 33763894), and octocrylene itself is systemically absorbed with plasma concentrations exceeding FDA thresholds after whole-body sunscreen application (PMID 31961417).
Effective UVB filter with broad absorption from approximately 280-320 nm; permitted in EU sunscreens at up to 10% under Annex VI entry 10; provides both UV filtration and photostabilization of other UV filters
Photostabilizer for avobenzone (butyl methoxydibenzoylmethane): octocrylene absorbs energy from excited avobenzone, preventing its photodegradation and maintaining UVA protection efficacy in combination sunscreen formulations
Good safety profile in acute toxicity: SCCP (1994) concluded non-toxic, non-irritant, and non-sensitising; confirmed by SCCS/1627/21 extended evaluation including reproductive toxicity studies showing no reproductive toxicity at up to 450 mg/kg bw/day
High photostability: stable in olive oil carrier for at least seven days at 305 nm; GC purity ≥99.4%; well-characterized physicochemical profile supports reliable formulation at permitted concentrations
Benzophenone (CAS 119-61-9) is a degradation product formed via retro-aldol condensation; SCCS/1627/21 states it is a hazardous impurity that must be monitored and kept at trace levels; benzophenone is reclassified as a suspected carcinogen (Category 2) under EU CLP
Systemic absorption confirmed in humans: octocrylene plasma concentrations exceeded FDA's 0.5 ng/mL threshold on day 1 of application across all four sunscreen formulations tested (JAMA 2020, PMID 31961417); maximum plasma concentration in lotion formulation was 7.8 ng/mL
Potential endocrine disrupting activity: SCCS/1627/21 notes inconclusive in vivo evidence suggesting endocrine effects; evidence insufficient to derive a specific endocrine-related toxicological point of departure; included in the EU Commission's 2019 priority list of 14 potential EDs for cosmetics safety assessment
Photoallergy: occurrence of photoallergic contact dermatitis to octocrylene is strongly associated with prior photoallergy to topical ketoprofen; SCCS/1627/21 notes the number of reported cases is negligible given widespread use
Propellant spray combined-use restriction: SCCS/1627/21 found that use of octocrylene at 10% or above in sunscreen propellant spray is not safe when used in combination with face cream, hand cream, and lipstick also containing octocrylene
SCCS Opinion on Octocrylene (CAS No 6197-30-4, EC No 228-250-8) — SCCS/1627/21, Final Opinion adopted 30-31 March 2021
“On the basis of safety assessment, and considering the concerns related to potential endocrine disrupting properties of Octocrylene, the SCCS is of the opinion that Octocrylene is safe as a UV-filter at concentrations up to 10% in cosmetic products when used individually.”— SCCS/1627/21 Final Opinion, p. 3 (Abstract section)