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Sunscreen Products (sunscreen + products)
Selected AbstractsRelationship between UVA protection and skin response to UV light: proposal for labelling UVA protectionINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 4 2004M. Jean-Louis Refrégier Synopsis Definition and validation of a most relevant method to assess ultravoilet A (UVA) protection is a major concern for industry, authorities and consumers. However, due to the lack of knowledge about all the biological phenomena involved, the level of UVA protection needed, the ways to assess and label it, remain controversial. In order to overcome this situation, the paper deals with the outcomes of a mathematical model to calculate the distribution between ultravoilet B (UVB) and UVA components of skin responses to UV light. Mathematical calculations of UVB and UVA erythemal components of skin response to sunlight are developed from the well-known determination procedure to calculate the sunburn protection factor (SPF) of sunscreens. The model establishes the relationship between the UVA component of skin erythemal response to overall UV radiation received from sunlight and the ratio SPF/PFAe (erythemal protection factor) where SPF is the product and PFAe is related to the UVA part of the sunlight. Depending on the efficacy profile of sunscreens, the skin erythemal response may be mainly promoted by UVB rays as it normally occurs in unprotected skin or on contrary by UVA rays. Therefore, the efficacy profile of sunscreens defines the deepness where biological events induced by sunlight take place. This new relationship pinpoints the tremendous importance of the protection afforded by sunscreen products in the UVA range when erythema is taken as biological response. By extrapolation of the model to any other biological skin response it becomes possible to predict how to improve the efficiency of sunscreen products in the future. UVA protection afforded by sunscreens should be improved until reaching the same level as the SPF protection factor so that all UV-induced biological responses could be prevented or lowered at the same extend. To enforce this improvement, a proposal to classify sunscreen products in relation with their UVA protection is made. Résumé Bien que les méfaits du rayonnement UVA soient à présent reconnus et l'importance de s'en protéger au même titre que ceux du rayonnement UVB totalement admise, l'obtention d'un consensus au niveau international, sur les méthodes pour mesurer l'efficacité des produits solaires vis-à-vis des UVA et sur les niveaux d'efficacité souhaitables, semble impossible à atteindre. Afin de tenter de surmonter les obstacles actuels, nous présentons un modèle mathématique qui permet d'établir la relation qui dèfinit le poids relatif des rayonnements UVB et UVA dans l'initiation des phénomènes biologiques engendrés par le rayonnement solaire, en fonction des caractéristiques du produit solaire utilisé et en particulier de son efficacité protectrice vis-à-vis des UVA. Dans le cas de l'érythème nous établissons ainsi que la proportion des effets engendrés par le rayonnement UVA est définie par le rapport SPF/PFAe: le SPF étant le facteur de protection contre l'érythème vis-à-vis de l,ensemble du rayonnement UV, c'est l'indice de protection affiché sur les produits; et, PFAe étant le facteur de protection du produit vis-à-vis du seul rayonnement UVA. L'extrapolation possible de ce modèle à l'ensemble des phénomènes biologiques met en évidence que le facteur de proportionnalité entre la protection globale et celle apportée vis-à-vis des UVA (SPF/PFAe) permet d'établir une classification de la qualité des systèmes filtrants en fonction de leur aptitude à prèvenir l'ensemble des méfaits du rayonnement solaire. Ce modèle démontre l'importance d'évaluer l,efficacité protectrice des produits solaires vis-à-vis du rayonnement UVA et son enseignement plus pertinent que celle de seulement évaluer l'allure des spectres d'absorption. Nous jugeons que l'application directe de ce modèle, au même titre que les méthodes d'évaluation de l,allure des spectres d'absorption, n'est aujourd'hui pas souhaitable en raison des connaissances et donc de la validation insuffisantes des méthodes in vitro en particulier pour évaluer les produits non parfaitement photostables. En conséquence, nous proposons de mettre en place une qualification qui repose sur l'évaluation de la protection UVA par les mèthodes in vivo dûment étudiées et validées telles que les méthodes PPD ou PFA. La mise en place du système proposé de qualification des produits solaires, permettrait d'apporter rapidement aux consommateurs une meilleure information sur la qualité des produits et permettrait de créer une dynamique d'amélioration de la qualité de l'ensemble des produits commercialisés. [source] Dosage de l'octyl dimethyl PABA, de l'homosalate et de l'octyl salicylate dans les produits de protection solaireINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2001M.-O. Masse Résumé La méthode décrit le dosage de l,octyl dimethyl PABA (2-ethylhexyl 4-(dimethylamino)benzoate) (CAS RN 21245-02-3), de l,homo-salate (3,3,5-trimethylcyclohexyl salicylate) (CAS RN 118-56-9) et de l,octyl salicylate (2-ethylhexyl salicylate) (CAS RN 118-60-5) dans les produits cosmétiques de protection solaire. L,échantillon est mis en suspension dans le méthanol et après traitement approprié, le dosage est effectué par HPLC/UV. La précision, le rendement et la fiabilité de la méthode ont été déterminés. Synopsis The method describes the quantitative determination of octyl dimethyl PABA (2-ethylhexyl 4- (dimethylamino)benzoate) (CAS RN 21245-02-3), homosalate (3,3,5-trimethylcyclohexyl salicylate) (CAS RN 118-56-9) and octyl salicylate (2-ethylhexyl salicylate) (CAS RN 118-60-5) in cosmetic sunscreen products. The sample is suspended in methanol and after appropriate treatment the determination is made by HPLC/UV. Accuracy, yield and viability of the method were resolved. [source] Unexpected Photolysis of the Sunscreen Octinoxate in the Presence of the Sunscreen Avobenzone,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2005Robert M. Sayre ABSTRACT A major concern raised about photostability studies of sunscreen products is that the photodegradation of sunscreens does not readily translate into changes in product performance. This study examines the correlation between photochemical degradation of sunscreen agents and changes in protection provided by sunscreen films. Films of a commercial sunscreen product containing avobenzone, oxybenzone and octinoxate were irradiated using a fluorescent UV-A phototherapy lamp with additional UV-B blocking filter. Periodically, during irradiation the transmittances of the films were measured and samples collected for chemical analysis of the sunscreen agents using high-performance liquid chromatography techniques. The results show that UV-induced changes in UV transmittance of sunscreen films correlate with changes in concentration of sunscreen agents. In a parallel experiment, we also irradiated a thin film of the same product in the cavity of an electron spin resonance (ESR) spectrometer. We report the concomitant photolysis of avobenzone and octinoxate that predominates over expected E/Z photoisomerization and that irradiation of a film of this product produced free radicals detected by ESR spectroscopy that persisted even after exposure had ended. [source] 019 The COLIPA Standard for solar simulators failed to standardize sunscreen SPFSPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 2 2002R.M. Sayre The COLIPA Standard for solar simulators was developed to insure that SPF tested in different laboratories was not different because of the solar simulator used. Indeed for products with lower SPFs 2-10, the solar simulator standard reasonably assures similar SPFs when tested in different laboratories. For products with SPFs greater than 15, the SPF for the same product could be tested at 15 in one laboratory but as an SPF 100 in another. Differences in SPF due to solar simulator filtration will occur only for sunscreen products that exhibit absorption like cut-off filters. Products which generally absorb all UV wavelengths equally will not exhibit differences in SPF due to solar simulator filtration. In addition because of different amounts of UVA allowed within the COLIPA standard, the actual response for a given exposure may in one laboratory produce persistent pigment darkening and in another a simple sunburn. Ways to correct this flaw will be examined. [source] Sunscreen protection in the ultraviolet A region: how to measure the effectivenessPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 1 2001C. Cole Products containing ultraviolet (UV) radiation absorbing or scattering ingredients provide varying degrees of protection from sunlight (or other UV sources), thus minimizing the deleterious effects on the skin. The "sun protection factor" (SPF) of sunscreen products has become a well recognized indicator of protection against sunburn induced predominantly by ultraviolet B radiation (UVB: 290,320 nm). A similar system of denoting sunscreen protection from ultraviolet A (UVA: 320,400 nm) radiation has not been universally recognized. A variety of test methods have been proposed, both in vitro and in vivo, each with specific virtues and shortcomings. Regulatory agencies and industry have been reviewing the available methods over the past decade in an effort to develop consumer meaningful claims and appropriate substantiation methods. This article reviews these test methodologies, in vitro and in vivo, as well as the biological background that establishes the need for UVA protection, and the UVA content of solar radiation and its variability. [source] Sunscreen ingredients and labelling: a survey of products available in the UKCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 4 2007S. Wahie Summary Background., In Europe, where sunscreens are classified as cosmetics, products may contain one or several of 27 permitted ,ultraviolet filters'. We were unable to find published data on the frequency of usage of individual ultraviolet (UV)-absorbing chemicals in currently available sunscreens. Aim., To record the active ingredients and labelling characteristics of sunscreens available in the UK. Methods., In 2005, two dermatologists visited seven retail outlets, which stocked a large range of sunscreens. Manufacturers were also contacted. For each product, the names of UV-protective ingredients and the labelling information, including sun protection factor (SPF), UVA protection and age group for which the product was marketed were recorded. Results., Data on 308 skin sunscreen products and 21 lip sunscreens were recorded. For skin products, the SPF ranged from 2 to 60. In total, 23 different UV-absorbing ingredients were found, 4 of which were found in >,25% of products. The child and baby skin sunscreens (n = 52) had a significantly higher median SPF of 40, compared with 15 for the remaining 256 adult products (P < 0.001). The number of UV-absorbing chemicals and the frequency of those commonly used did not differ substantially between child and adult products. Of skin sunscreens marketed for babies, 60% contained 2,6 UV-absorbing chemicals. Nearly half of the skin sunscreens contained at least one of nine UV-absorbing chemicals not available in patch testing formulations from commercial suppliers. Conclusions., The results of this survey indicate current sunscreen content and labelling, and are a benchmark from which new developments can be tracked. More standard sunscreen labelling, particularly separate listing of active ingredients, would be helpful. It was surprising to find UV-absorbing chemicals in products sold for use on babies. [source] | ||||||||||