Octocrylene

Octocrylene is a documented photocontact allergen — photo-allergic contact dermatitis is the predominant concern, occurring especially in adults who have previously been sensitised to the NSAID ketoprofen (a substituted benzophenone). Contact allergy without UV exposure is rarer and observed more often in children. In patch-test populations, photocontact allergy was observed in approximately 4% of sensitised patients and contact allergy in 0.7%. Reactions are rare in the general population but the risk is non-trivial. Additionally, octocrylene degrades over time into benzophenone, a known sensitiser and endocrine disruptor, which may accumulate in products. EU Annex VI (Commission Regulation (EU) 2022/1176) restricts octocrylene to 10% in non-spray products and 9% in propellant spray products; benzophenone as a degradation product must be kept at trace levels.

There is evidence that octocrylene has reproductive toxicity concerns. Its primary degradation product, benzophenone, is a known endocrine disruptor associated with altered thyroid hormones in pregnant women and effects on reproductive development in offspring. Studies have detected systemic absorption through skin. Most dermatologists and safety bodies advise caution during pregnancy; some recommend avoiding octocrylene-containing products altogether, particularly leave-on formulations. Consult a healthcare provider before use during pregnancy. (Sources: EWG Sunscreen Guide; Endocrine and Reproductive Health Considerations of Sunscreen UV Filters, PMC 2024.)