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Retrospective Review of Dermal Safety Studies of Organic Sunscreens
Background:
Sunscreens can reduce skin cancer and sunburn. Recent studies on dermal penetration have raised concerns about the safety of sunscreens with organic ultraviolet (UV) filters.
Objective:
The aim of the retrospective study was to assess the dermal safety of chemical sunscreens containing the chemical filters avobenzone, octocrylene, homosalate, and octisalate.
Method:
A retrospective assessment was conducted of clinical results on sunscreen products of human repeat irritation patch test, cumulative irritation, photo allergy, and photo toxicity.
Results:
An analysis of human repeat irritation patch test results involving 38,950 subjects demonstrated that 99.5% of participants experienced no sensitization. Seven participants exhibited a reaction, which was attributed to the preservative rather than the UV filters. Cumulative irritation results in 4,715 subjects showed that 97.8% of participants had no visible irritation, and 29 subjects showed the lowest irritation grade, representing a barely perceivable erythema. No photo-allergy or photo-toxicity reactions were observed.
Conclusion:
The findings show no to minimal risks of dermal irritation, sensitization, photo-allergy, and photo-irritation, reinforcing the safety profile of these sunscreens. This evidence is valuable in reassuring the public about the strong safety record of organic sunscreens.

