Background: Today, the sun protection factor (SPF) value of sunscreen products is determined in vivo with a standardized protocol (EN ISO 24444:2010), and the measured SPF biological end point is the visible skin erythema. However, many of the sunscreen products currently available on the market have antiphlogistic ingredients, which may potentially result in an overestimated SPF of the sunscreen. Aims: To investigate the potential influence of the antiphlogistic ingredients panthenol and bisabolol in sunscreens on the determined SPF value in vivo. Methods: Formulations with different concentrations of the antiphlogistic ingredients bisabolol or panthenol were tested. As a reference, a base formulation (vehicle) without antiphlogistic ingredients was used. First, the SPF of the sunscreen formulas with and without antiphlogistic ingredients was analyzed in vitro. To investigate whether the antiphlogistic ingredient may suppress the inflammatory response to ultraviolet (UV) irradiation, the SPF was determined in vivo. Finally, selected formulations were also analyzed in an erythema model for testing formulations on UV-induced inflammation. Results: It could be confirmed that no differences between the formula with and that without the active antiphlogistic ingredients bisabolol or panthenol exist when measured in vitro. However, there was also no statistically significant difference in the erythemal response between the vehicle (without an antiphlogistic active ingredient) and the test formulations with different concentrations of the antiphlogistic active ingredients in the in vivo determination of the SPF. Evidence of anti-inflammatory activity of the sunscreen antiphlogistics bisabolol and panthenol was also not apparent in the UV model over a time course of 48 h. Conlusion: The antiphlogistic ingredients panthenol and bisabolol incorporated in the tested sunscreen formula do not interfere with erythema reddening and thus do not affect the SPF value in vivo.

1.
Regulation (EC) No. 1223/2009 of the European Parliament and of the Council of 30 November 2009 on cosmetic products (recast) (text with EEA relevance), Official Journal of the European Union, L 342/59, 22 December 2009.
2.
Guidelines to Commission Regulation (EU) No. 655/2013 laying down common criteria for the justification of claims used in relation to cosmetic products (July 2013 version).
3.
Cosmetics I: sun protection factor test methods - in vivo determination of SPF (sun protection factor).
4.
Maurya AK, Singh M, Dubey V, Srivastava S, Luqman S, Bawankule DU: Alpha-(-)-bisabolol reduces pro-inflammatory cytokine production and ameliorates skin inflammation. Curr Pharm Biotechnol 2014;15:173-181.
5.
Haydar K, Burkhart CG: Sunscreen regulations and use of anti-inflammatory agents in sunscreens. Dermatol Online J 2013;19:18969.
6.
Sayre RM: Rapid precision testing laboratory: Citizen Petition FDA, 15 March 2013.
7.
Fitzpatrick TB: The validity and practicality of sun-reactive skin types I through VI. Arch Dermatol 1988;124:869-871.
8.
Fitzpatrick TB: Soleil et peau. J Med Esthet 1975;2:33-34.
9.
Del Bino S, Bernerd F: Variations in skin colour and the biological consequences of ultraviolet radiation exposure. Br J Dermatol 2013;169(suppl 3):33-40.
10.
Hughes MC, Williams GM, Baker P, Green AC: Sunscreen and prevention of skin aging: a randomized trial. Ann Intern Med 2013;158:781-790.
11.
Couteau C, Chauvet C, Paparis E, Coiffard L: UV filters, ingredients with a recognized anti-inflammatory effect. PLoS One 2012;7: e46187.
12.
Dewhirst F: 2-Hydroxybenzophenones and their use in treating inflammation. US Forsyth Dental Infirmary for Children 1981, vol 4.
13.
Staton J, Feng H: Anti-inflammatory effects of sunscreens - wonder or science? Sci Beauty 2015;4:57-61.
14.
Couteau C, Chauvet C, Paparis E, Coiffard LJ: Influence of certain ingredients on the SPF determined in vivo. Arch Dermatol Res 2012;304:817-821.
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