What level of photoprotection can be obtained using facial mask? Determining effectiveness using an in vitro method.

It has become a general practice worldwide to wear a face mask serving as a barrier against the transmission of pathogens. This has prompted us to investigate whether masks could also protect our skin from UV radiation. We have studied eight masks, four surgical and four "homemade" using an in vitro method. The study demonstrated that they all offered protection against both UVB and UVA radiation. As with clothing, fabric masks offer the highest level of protection against UV radiation.

Demonstration of the dangerous nature of 'homemade' sunscreen recipes.

BACKGROUND: Following a growing mistrust in a certain number of ingredients used by the cosmetic industry, it has become popular in recent years for consumers to make their own products at home. This trend now touches on all areas of the industry, but is especially found in the hygiene sector, with shampoos and toothpaste, and the care sector, with moisturizers and sunscreen, products. OBJECTIVES: The objective of this study is to analyze sunscreen recipes found on the Internet and to assess their level of photoprotective efficacy. MATERIALS AND METHODS: Fifteen Internet recipes were chosen, and then, the products were made in the laboratory following the protocols described. Using an in vitro method, the following efficacy indicators were determined for the preparations made: the Sun Protection Factor (SPF), the Production Factor in the UVA domain (PF-UVA), and the critical wavelength (λc ). RESULTS: Three of the 15 recipes studied do not contain any sunscreen and therefore constitute a major risk for users in case of exposure to the sun. The other 12 cannot be considered as sun protection products since all of them have an SPF under 6, the threshold value required in Europe. CONCLUSION: The recipes that we collected on the Internet are very dangerous since some of them have no photoprotective effect whatsoever and most of them do not ensure a sufficient level of photoprotection for the persons using them.

Evaluation of Different Colorless Nail Polishes Used as Supportive Care in Patients with Cancer in Terms of Photoprotective Efficacy and Water Resistance.

Background: In patients undergoing chemotherapy, the application of nail polish and/or a colorless base coat is recommended in order to prevent the adverse effects that can occur on the nails throughout treatment. Objective: In this study, the photoprotective effects of different clear nail polishes were examined. Methods: Twelve commercially available, colorless nail products were tested in vitro. Two layers of the product were applied, as recommended to patients, on polymethyl methacrylate (PMMA) plates. The efficacy indices in the ultraviolet (UV) B sun protection factor (SPF) and UVA regions were then determined with an integrated sphere spectophotometer. Water resistance was also evaluated. Results: Certain colorless nail polishes, such as Mavala 6 Osaka or CC bleaching base with silicium for yellow nails (Vitry), can provide a significant level of photoprotection, with SPF values of above 150. All of the products tested, with the exception of the aqueous gel, are water resistant. Conclusion: Colorless nail polish applied in two layers provides UV protection for the nails in the UVB and UVA ranges. The nature of the vehicle influences the photoprotective efficiency and the water resistance.

[Comparison of different nail polish in terms of photoprotective efficacy. Interest of their use as supportive care in patients with cancer]. / Comparaison de différents vernis à ongles en matière d'efficacité photoprotectrice. Étude de l'intérêt de leur recours en soins de support en oncologie.

Many different chemotherapy drugs including cytotoxics and docetaxel in particular are responsible for side effects involving the nails. To prevent these negative effects, patients are advised to apply nail polish. The aim of this article is to study the photoprotective effect of various products applied in two layers. Sixty-five commercially-available products were tested in vitro. It was found that certain bases can provide non-negligible levels of photoprotection on their own. However, it was noted that nail polishes capable of forming an opaque film were the most interesting, with Sun protection factor (SPF) values of 500 or more, which is a lot higher than the values obtained with sun protection products and similar to levels which can be reached with protection through clothing. It appears that opaque nail polishes applied in two layers are likely to provide excellent protection for nails regarding ultraviolet radiation. If the dark colors are particularly effective towards the ultraviolet radiation, we can also obtain a very good protection with varied colors. The use of one or several UV filters in the formula of the mail polish does not appear to have a particular interest.

BB creams and their photoprotective effect.

BB creams appeared on the market quite recently. These creams, which give a perfect complexion by covering up the skin's blemishes, have a photoprotective effect in the majority of cases. An SPF value ranging from 10 to 45 concerning the products we tested is displayed on the packaging. The 21 commercially-available BB creams were tested to assess their efficacy (determination of the SPF) and their photostability (determination of their efficacy after UV irradiation). It was shown that 70% of the products tested have an SPF determined in vitro by us which matches the SPF displayed on the product. For the remaining 30%, it can be seen that products have SPF values of between 2 and 10 times lower than those indicated on the products. It can also be noted that there is a large disparity in terms of photostability since, under the same experimental conditions, however, some products only lose 5% of their photoprotective efficacy, whereas others lose 60%.

Influence of certain ingredients on the SPF determined in vivo.

When determined in vitro, the SPF of certain commercial sunscreen products can be lower than the SPF indicated on the label. The study of the composition of this type of product enabled us to note that the majority contained substances reputed to have anti-inflammatory properties. This effect is shown by inhibiting the erythema, without protecting the skin, which constitutes a serious public health problem. The anti-inflammatory effects of αbisabolol-, allantoin- and 18-ß-glycyrrhetinic acid-based emulsions, as well as commercial sun products containing any one of these molecules, have been tested with phorbol myristate acetate on mice. The effectiveness of these sunscreens products is quantified using two indicators: SPF (sun protection factor) and PF-UVA (protection factor-UVA) by in vitro method. We were thus able to show that certain sun products have an anti-inflammatory effect, which in turn causes the SPF value shown on the product to be overestimated, indeed sometimes by considerably large margins.

UV filters, ingredients with a recognized anti-inflammatory effect.

BACKGROUND: To explain observed differences during SPF determination using either an in vivo or in vitro method, we hypothesized on the presence of ingredients having anti-inflammatory properties. METHODOLOGY/PRINCIPAL FINDINGS: To research our hypothesis, we studied the 21 UV filters both available on the market and authorized by European regulations and subjected these filters to the phorbol-myristate-acetate test using mice. We then catalogued the 13 filters demonstrating a significant anti-inflammatory effect with edema inhibition percentages of more than 70%. The filters are: diethylhexyl butamido triazone (92%), benzophenone-5 and titanium dioxide (90%), benzophenone-3 (83%), octocrylène and isoamyl p-methoxycinnamate (82%), PEG-25 PABA and homosalate (80%), octyl triazone and phenylbenzimidazole sulfonic acid (78%), octyl dimethyl PABA (75%), bis-ethylhexyloxyphenol methoxyphenyl triazine and diethylamino hydroxybenzoyl hexylbenzoate (70%). These filters were tested at various concentrations, including their maximum authorized dose. We detected a dose-response relationship. CONCLUSIONS/SIGNIFICANCE: The anti-inflammatory effect of a sunscreen ingredient may affect the in vivo SPF value.

Silymarin, a molecule of interest for topical photoprotection.

Some UV-filters have side effects. For example, oestrogenic effect was demonstrated for 4-methylbenzylidene camphor. Given that secondary metabolites are known for their UVB photoprotective properties in plants that contain them, we chose to study silymarin as an agent which could potentially be used in sun products. This determination is based on the physical determination of the reduction of the energy in the UV range, through a film of product which has previously been spread on an adequate substrate. About 15 mg of O/W emulsion containing silymarin at various concentrations was applied on roughened PMMA plates and the transmission measurements were carried out using a spectrophotometer equipped with integrating sphere. Incorporated in O/W creams, at a concentration of 10% (w/w), silymarin gives a Sun Protection Factor similar to that of octylmethoxicinnamate, which is why it is predominantly used in Europe. Overall, these results demonstrate that silymarin is a promising new sunscreen agent.

Foundations and self-tanning products: Do they provide any protection from the sun?

As soon as the weather turns sunny, everyone wants a tan. People with skin phototypes III and IV, called melanocompetent, have no problem meeting this fashion requirement. But things are quite different for people with phototypes I and II and so these individuals look for alternative solutions. In essence, light skin burns easily when exposed to the sun. Therefore, light-skinned people are offered a cosmetic solution through self-tanning products or foundations. It seemed interesting to us to evaluate the sun protection power of this type of product. To do this, we used an in vitro method to determine the typical indicators related to sunscreen products, such as sun protection factor (SPF), ultraviolet (UV)-A protection factor (PF-UVA), UV-B/UV-A ratio as well as the critical wavelength because these artificial tanning products could be considered sunscreen products by users. It is important to know whether a self-tanning product and/or a foundation provide sun protection and whether they meet the standards set for other sunscreen products. Protection which is imbalanced for either UV-B or UV-A radiation is potentially harmful for users believing themselves adequately protected. To do this, we assembled the requisite conditions for forming melanoidins in the cosmetic itself. We tested seven amino acids found in the corneal cells of the epidermis. Regardless of the amino acid used, the corresponding SPF was essentially zero (approximately SPF 2). Foundations, on the other hand, proved to be much more interesting because they possess a non-negligible SPF as well as good photostability making these products safe in terms of their mode of application (applied once daily).

Flavonoids and polyphenols, molecular families with sunscreen potential: determining effectiveness with an in vitro method.

The numerous uses and properties of flavonoids are well known, in particular their antioxidant, cancer-control and antiinflammatory effects. These properties can be used to enrich the field of topically-applied sun protection. The aim of the study was to determine the effectiveness of various flavonoids and polyphenols. We have used an in vitro method based on the transmittance measurement after spreading an oil in water emulsion containing either flavonoids or polyphenols on polymethylmetacrylate plates. Chlorogenic acid and apigenin were the best UV-filter and UVA-filter, respectively. The flavonoids and polyphenols studied are good candidates for us e in photoprotective products.

Interest of ferulic acid ethyl ester in photoprotective creams: measure of efficacy by in vitro method.

Topical sunscreens have been used for many years on exposed areas to protect the skin from the damaging effects of ultraviolets. If the sunscreens were essential, it is suggested that they have adverse effects. We chose to study ferulic acid ethyl ester (FAEE) as agent which could potentially be used in sunscreen products. FAEE was incorporated at various concentrations into O/W emulsions. Total of 30 mg of product exactly weighed were spread on poly(methylmethacrylate) plates over the whole surface (25 cm(2)). So, sun protection factor (SPF) and PF-UVA of the creams were measured in vitro. Transmission measurements between 290 and 400 nm were carried out using a spectrophotometer equipped with an integrating sphere. Incorporated in O/W creams, at a concentration of 10%, FAEE give a SPF similar to that of benzymidazilate, a filter permitted in EU.

Quercetin and rutin as potential sunscreen agents: determination of efficacy by an in vitro method.

Given that flavonoids are known for their ultraviolet (UV)B photoprotective properties in plants that contain them, we chose to study quercetin (1) and rutin (2) as agents that could potentially be used in sunscreen products. These two substances proved to behave in similar ways. When incorporated in oil-in-water emulsions, at a concentration of 10% (w/w), 1 and 2 give sun protection factor (SPF) values similar to that of homosalate, a standard substance. These two flavonoids also provided a non-negligible level of photoprotection in the UVA range. When used in association with titanium dioxide, the SPF obtained was around 30.

Photoprotective activity of propolis.

The purpose of this study was to determine the photoprotective properties of propolis. The sun protection factor (SPF) of ethanol extract of propolis was evaluated by an in vitro method, using homosalate as control. This determination is based on the physical determination of the reduction of the energy in the UV range, through a film of product which has previously been spread on an adequate substrate. About 15 mg of O/W emulsion containing propolis at various concentrations were applied on roughened Polymethylmethacrylate (PMMA) plates and the transmission measurements were carried out using a spectrophotometer equipped with integrating sphere. The results may justify their use as a natural sunscreen agent.

Study of the photostability of 18 sunscreens in creams by measuring the SPF in vitro.

The target of this research was to evaluate the photostability of various sunscreen agents incorporated into an O/W emulsion. The concept of photostability is very important in the field of solar protection. The effectiveness of the anti-solar products is quantified using a universal indicator: the sun protection factor (SPF). This number which can be found on packaging can be given in two different ways: by methods in vivo (Colipa method) and in vitro. It is this last method which was adopted for this study. According to selected filter UVB (currently directive 76/768/EEC modified authorized 18 filters UVB), we can obtain more or less effective creams. We chose the irradiation of sun lotions formulated using the authorized filters, used with their maximum amount of employment, in a Suntest, with an irradiance of 650 W/m(2) throughout variable time. With interval of regular time, one carries out a measurement of SPF in order to establish for each filter the kinetics SPF=f(time). An indicator of stability (t(90)) is then given. In this way, we could classify the filters by order of increasing photostability.