Assessment of Natural Sunlight Protection Provided by 10 High-SPF Broad-Spectrum Sunscreens and Sun-Protective Fabrics.

In 1978, the FDA Advisory Panel proposed both indoor and natural sunlight SPF testing methods but reverted to indoor testing only in 1993. Today's sunscreen sun protection and broad-spectrum claims are based on mandated clinical tests using solar simulators and in vitro spectrophotometers. This research evaluated the protection of 10 high-SPF (30-110), broad-spectrum sunscreen products, as well as 6 sun-protective fabrics against natural sunlight in Arequipa, Peru. Each of the 17 subjects was exposed to natural sunlight for 1 h and 59 min under clear skies, with temperatures and humidity similar to those in an indoor clinical laboratory. Test sites were photographed 16-24 h later. Four dermatologists evaluated the photographs for erythema and persistent pigment darkening (PPD). Perceptible sun-induced skin injury (sunburn and/or pigmentation) was detected at 97% of the sunscreen-protected scores. The most sun-sensitive subjects obtained the least erythema protection. The higher the SPF was, the higher the erythema protection, but the intensity of PPD was also higher. The 2 sunscreens using only FDA-approved sunscreen filters rated 30 SPF and 45+ SPF performed poorly: Eighty-one percent of the 136 scores were graded 1 minimal erythema dose or higher erythema, achieving, at a maximum, SPF of 5-7 in natural sunlight. Sun-protective fabrics tested provided excellent sun protection. The erythema and PPD observed through the sunscreens in less than 2 h are incongruous with the broad-spectrum, high-SPF sunscreen claims. Reapplying these sunscreens and staying in the sun longer, as stated on the product labels, would have subjected the subjects to even more UV exposure. High-SPF, broad-spectrum sunscreen claims based on indoor solar simulator testing do not agree with the natural sunlight protection test results.

In vitro and in vivo photoprotective/photochemopreventive potential of Garcinia brasiliensis epicarp extract.

The damaging effects of sunlight to the skin has triggered studies that involve the synthesis and extraction of organic compounds from natural sources that can absorb UV radiation, and studies on polyphenolic compounds with antioxidant and anti-inflammatory properties that can be used as photochemopreventive agents for reducing skin damage. We investigated the in vitro and in vivo photoprotective/photochemopreventive potential of Garcinia brasiliensis epicarp extract (GbEE). We evaluated the cell viability of L929 fibroblasts after UVB exposure using a quartz plate containing the extract solution or the GbEE formulation. The in vivo photoprotective effect of the GbEE formulation was evaluated by measuring the UVB damage-induced decrease in endogenous reduced glutathione (GSH), the increase in myeloperoxidase (MPO) activity and secretion of cytokines IL-1ß and TNF-α. The in vitro methodology using fibroblasts showed that the photoprotective properties of the GbEE solutions and 10% GbEE formulation were similar to the commercial sunscreen (SPF-15). In vivo results demonstrated of the GbEE formulation in decreasing UVB induced-damage such as GSH depletion, an increased in MPO activity and secretion of cytokines IL-1ß and TNF-α. The results showed that the extract has great potential for use as a sunscreen in topical formulations in addition to UV filters.

Filtros solares: normas de utilizaçäo / Solar filters: standards for utilization

As radiaçöes solares alcançam a Terra em forma de ondas. De maior interesse säo as ondas ultravioletas situadas no espectro de 200 a 400 nanômetros, por seu potencial carcinogênico sobre a pele, assim como pela produçäo de fotoenvelhecimento cutâneo e imunodepressäo. Os efeitos dessas radiaçöes sobre a pele dependem da interaçäo de fatores ambientais com fatores de sensibilidade individuais, como fototipo e fotossuscetibilidade. Os fotoprotetores säo agentes com açäo física ou química, que atenuam o efeito da radiaçäo UV por mecanismos de absorçäo, reflexäo ou dispersäo da radiaçäo. A qualidade de um fotoprotetor depende de seu fator de proteçäo solar (FPS) e de suas propriedades físico-químicas (formaçäo de uma película ideal sobre a pele, estabilidade, baixa hidrossolubilidade e hipoalergenicidade). Novos princípios ativos estäo sendo pesquisados, visando a minorar os efeitos adversos desses produtos, como a melanina sintética, o óxido de ferro e as vitaminas antioxidantes. Paralelas à importância da qualidade de um fotoprotetor estäo a reeducaçäo de hábitos e a orientaçäo de seu uso adequado

Determinaçäo in vitro do fator de proteçäo solar (FPS) de moderadores solares / In vitro determination of sum protection factor (SPF) of solar moderators

Os Fatores de Proteçäo Solar (FPS) de vários produtos comerciais brasileiros, estrangeiros e um produto padräo FDA foram determinados in vitro por duas técnicas de transmissäo ótica simples. Os produtos solares foram aplicados sobre uma nova pele artificial biológica (Biofill). Os resultados estäo de acordo com os valores FPS determinados in vivo. A técnica e o material do substrato podem conduzir a um novo protocolo padräo para a determinaçäo in vitro rápida e segura dos valores FPS dos moderadores solares