Cutaneous Photoprotection: A Review of the Current Status and Evolving Strategies.

Ultraviolet radiation (UVR) exposure is well established as the major environmental risk factor for the development of melanoma, cutaneous squamous cell carcinoma (cSCC), and basal cell carcinoma (BCC). Additional risk factors including genetic mutations, other environmental agents, and immune status are important in modulating the effects of UVR. Dermatologists advocate a multi-pronged approach to minimizing UVR exposure including lifestyle modifications, UVR protective clothing, and topically applied sun-protective products, i.e. sunscreen. New Federal Drug Administration (FDA) regulations on sunscreen have brought certain long-standing ingredients in sunscreen products under scrutiny. The FDA's proposed rule for over the counter (OTC) monograph states that the inorganic sunscreens, zinc oxide and titanium dioxide, were found to be "generally recognized as safe and effective," but cite insufficient evidence to grant organic sunscreens the same designation. This proposed rule by the FDA and our increasing understanding of multifactorial mechanisms of UVR damage are an impetus for innovation and advances in sun protective technology. A complete set of strategies designed to limit the risk of UV-induced skin cell malignant transformation and tumor development must address the fuller consideration of genetic, environmental, and immune factors that cooperatively drive cutaneous carcinogenesis. Recent advances in our understanding of the biochemical processes underpinning UVR associated cutaneous cellular damage, genotoxicity, and clonal expansion provide investigators with a spectrum of opportunities for technologic innovation in the prevention of skin cancer. Strategies to improve upon current topical sunscreen formulations have strived for broader UVR spectral coverage, more favorable aesthetics, increased adherence, and minimal penetration into the living epidermis. In addition to improved sunscreens, future topical therapies may target processes within the epidermis that contribute to carcinogenesis. These include reactive species quenching, delivery of DNA repair enzymes, and targeting of cytokines essential to the proliferation of mutant keratinocytes.

Cosmetic Versus Medicine: How Does Your Country Define Sunscreen?

Skin cancer (melanoma and non-melanoma) is the most commonly diagnosed cancer in the United States of America, and non-melanoma skin cancer is the most common cause of Australian hospitalisations with cancer as the principle diagnosis, having a huge cost to the country's health care system. Primary and secondary skin cancer prevention is globally inadequate, with only 3 in 10 American adults using sun protection routinely. Evidence suggests that regular sunscreen use in Australians prevents both melanoma and non-melanoma skin cancers, and American research has found that daily sunscreen use reduced the incidence of melanoma - the most skin cancer deaths - by half. Despite this, in many countries and regions around the world, a major ongoing divergence remains on the classification of sunscreen as either a cosmetic product or a form of medical therapy, which in turn affects the consumers' attitudes towards the use of sunscreen. This is also affected by the increasing use of the internet, which has made the purchasing of products internationally convenient and easy for consumers worldwide, including sunscreen products, which are frequently marketed online. There is variation between each country or region and their regulations of sunscreen affect the consequent labelling claims of sunscreen products. This affects the unsuspecting consumer's choices in purchasing sun protection, which may be misinformed. Australia, Canada, and the US are the only countries to classify sunscreen as a form of medical therapy. This paper explores the current classification of sunscreen products in countries and regions around the world and discusses the impact of these discrepancies and similarities on the attitudes of consumers towards sunscreen use. Finally, we make suggestions on changes that can be made to encourage sunscreen use and safe sunscreen purchasing. J Drugs Dermatol. 2018;17(8):899-904.

[Sun protection factor 50+ : Pro and contra]. / Lichtschutzfaktor 50+ : Pro und Kontra.

The use of sunscreens with sun protection factors beyond 50 is controversial. In order to avoid misleading the consumer, several countries have already decided not to declare SPF beyond 50 on sunscreen products. Arguments against high SPF include the following: the risk of imbalanced protection, which could increase the risk of damage caused by longer-wave ultraviolet radiation; imparting a false sense of safety, which could lead to the extension of sun exposure times; health risks from higher concentrations of filter substances; and the only marginally higher blockade provided by high SPF sunscreens. On the other hand, it has been realized that the functional SPF of sunscreens remains far behind the declared SPF in the practical application and, therefore, the use of higher SPF in sensitive individuals and during strong UV exposure could make sense.

Simultaneous in-vial acetylation solid-phase microextraction followed by gas chromatography tandem mass spectrometry for the analysis of multiclass organic UV filters in water.

UV filters are a class of emerging contaminants that are widely used in personal care products (PCPs) and that can be detected at low concentrations in the aquatic environment (ngL-1). Sensitive modern analytical methods are then mandatory to accurately analyze them. A methodology based on solid-phase-microextraction (SPME), considered as a 'Green Chemistry' technique, followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) has been developed for the simultaneous analysis of 14 UV filters of different chemical nature in environmental and recreational waters. In-vial low-cost derivatization was carried out to improve chromatographic performance of phenolic compounds. The extraction parameters (fiber coating, extraction mode, and salt addition) were optimized by means of experimental designs in order to achieve reliable conditions. Finally, the SPME-GC-MS/MS method was validated in terms of linearity, accuracy and precision with LODs in the low ngL-1 level. Its application to the analysis of 28 different samples including sea, river, spa, swimming pool, and aquapark waters, enabled the detection of 11 target UV filters at concentration levels up to 540µgL-1, highlighting the presence of OCR in all analyzed samples and of 2EHMC (proposed to be considered as priority pollutant) in 79% of them.

Sunscreens in the United States: current status and future outlook.

Incidence rates of nonmelanoma skin cancer and melanoma has been on the rise in the United States for the past 20 years. UV radiation (UVR) exposure remains the most preventable environmental risk factor for these cancers. Aside from sun avoidance, sunscreens remain our best protection. UVR directly damages DNA and cause indirect cellular damage through the creation of reactive oxygen species, the sum of which leads to cutaneous immunosuppression and a tumorigenic milieu. The current generation of sunscreens protect from UVR through two main mechanisms: absorption and deflection. In the US, new Food and Drug Association rules require sunscreen manufacturers to evaluate their products not only on sun protection factor but also on broad spectrum UVA protection by the end of 2013. New labeling requirements will also be instituted. The American Academy of Dermatology and the American Academy of Pediatrics have provided specific recommendations for proper sun protection and sunscreen usage. Plant polyphenols such as those isolated from green tea, pomegranate, and grape seed remain an interesting avenue of research as additives to sunscreens or stand-alone products that appear to modulate the immunosuppressive effects of UVR on the skin. Additionally, although UVR induces endogenous cutaneous production of vitamin D, its damaging effects overshadow this positive benefit, especially in light of the ease of achieving recommended amounts of vitamin D through diet and supplementation.

The economic burden of sunscreen usage.

Excessive sun exposure is known to be the leading cause of skin cancer. The direct cellular damage inflicted by the ultraviolet (UV) radiation from the sun results in premature aging, DNA damage, and mutations that ultimately lead to skin cancer. Sunscreens are highly recommended to protect against UV radiation. However, little research has been conducted on the economic burden of sunscreen use. In this study, we aimed to evaluate the annual cost of sunscreen under both ideal and actual use conditions while stratifying for the sun protection factor (SPF) and by the name brand or equivalent store brand sunscreen. Pricing data was collected for sunscreens of SPF 30, 50, 70, and 100. For each type of sunscreen, the size and price of the container were recorded. Our results demonstrated that sunscreen prices increased with SPF but purchasing a generic sunscreen resulted in savings of 40%-50%. Our estimates reveal that sunscreens are affordable with annual expenditures ranging from $30.21 to $61.94, depending on brand, for SPF 50 sunscreens used with minimal application density for the average person.

Simplifying sun safety: a guide to the new FDA sunscreen monograph.

Dermatologists are instrumental in educating their patients about safe sun practices. As residents, we should begin to instill this teaching point into our daily patient encounters. The new US Food and Drug Administration sunscreen guidelines, instituted fully in December 2012, help consumers make more educated decisions about sunscreens they purchase but also introduce new classifications and claims with which dermatologists should be intimately familiar. This article aims to concisely summarize the revisions as well as any continued controversies with the guidelines.

Better understanding of the EU regulatory frameworks for cosmetic products.

This letter to the editor corrects some misunderstandings regarding the EU regulations covering cosmetic products stated in a recent publication by A. Sobek et al. "In the shadow of the cosmetics directive - Inconsistencies in EU environmental hazard classification requirements for UV-filters" published in Science of the Total Environment 461-462 (2013) 706-711.

In the shadow of the Cosmetic Directive--inconsistencies in EU environmental hazard classification requirements for UV-filters.

UV-filters are chemicals with potentially environmental hazardous properties. In the European Union (EU), UV-filters contained in sunscreen products are currently regulated by the Cosmetic Directive (from July 2013 by the Cosmetic Products Regulation). Environmental hazard classifications according to the regulation on classification, labelling and packaging of substances and mixtures (CLP) must be determined for UV-filters contained in industrial chemical products, whereas UV-filters contained in sunscreens are exempted from CLP. In this study we determined the potential environmental hazard classifications of UV-filters and sunscreen products if the CLP regulation was to be required for cosmetic products. Two sunscreen products were evaluated in accordance with the aquatic environmental hazard criteria for mixtures. The results highlight that the inconsistencies in the current EU regulation of UV filters hamper the risk management of environmental hazards of UV filters used in cosmetic products. Almost 50% of the investigated UV-filters approved for use in cosmetic products on the European market according to the current Cosmetic Directive were identified to meet the CLP classification as being hazardous to the aquatic environment. Assuming a worst-case scenario, the two examined sunscreens could both be classified as hazardous to the aquatic environment with long-lasting effects according to CLP classification criteria. Hence, if the CLP regulation was applicable to sunscreen products, both brands could potentially be labelled with the environmental hazard pictogram and associated hazard and precautionary statements. Including cosmetic products, and thereby sunscreens, in the CLP regulation would contribute to a more harmonized and transparent regulation of potentially hazardous substances on the EU market.

Fotoproteção na prática clínica / Photoprotection in clinical practice

A exposição solar sem a adequada proteção pode ter efeitos agudos e crônicos prejudiciais à pele. A escolha do tipo de proteção solar depende da idade, fototipo de pele e das atividade individuais. Os autores fazem uma revisão bibliográfica sobre os tipos de radiação e a respectiva proteção solar.

The sun exposure with no adequate protection may have acute and chronic detrimental effects in skin. The choice of the type of photoprotection depends on the age, skin phototype and individual activities. The authors make a literature review about the types of radiation and photoprotection.

The effect of sunscreen on melanoma risk.

Total cumulative sun exposure is associated with the development of squamous cell and basal cell cancers, whereas intense intermittent sun exposure is associated with the development of melanoma. Exposure to UV radiation is the only known modifiable cause of melanoma, but the role of sunscreen in melanoma prevention remains somewhat controversial. This article discusses how UV radiation contributes to the pathogenesis of melanoma, how sunscreen modulates the action of UV radiation on the skin, and the effect of sunscreen on the risk of developing melanoma. A review of available sunscreen agents and their sun-protective properties is also included.

UV protection and sunscreens: what to tell patients.

Ultraviolet (UV) radiation is the major environmental risk factor for nonmelanoma skin cancer and is a suspected risk factor for melanoma. Avoiding overexposure to direct sunlight during the peak daylight hours, wearing protective clothing, and applying sunscreen are ways to protect the skin. To provide clinicians with the tools to advise patients and to answer their inquiries, including which sunscreen to use, we review UV radiation's effect on the skin, how sunscreens block UV light, current recommendations on sunscreen use, and new sunscreen labeling requirements.

Considerations on photoprotection and skin disorders.

Excessive exposure to solar or artificial sources of UV radiation is deleterious to the skin and can cause or worsen several diseases. Detrimental effects of UV radiation exert an important role in the development of skin cancers, cause alterations on the immune response, and act as a trigger or aggravating factor for pigmentary disorders. A group of measures, including education, change of habits, use of physical barriers and sunscreens constitutes a significant part of the treatment of many skin disorders and are valuable preventive tools. This article summarizes the relevant studies addressing these issues, emphasizing the many aspects of photoprotection.

Photoprotective efficacy and photostability of fifteen sunscreen products having the same label SPF subjected to natural sunlight.

The first objective of this study is to show how different can be photoprotection by sunscreens with an identical SPF given on the packaging, when subjected to sunlight radiation. The second objective is to highlight the need for global harmonization of photostability testing and UVA protection labelling. Fifteen products with various combinations of UV filters marketed in Europe were assessed based on transmission measurements of 0.75 mg cm⁻² layer covered onto polymethylmethacrylate plate roughness 2 µm. Two absolute UV spectroscopic indices (in vitro SPF, UVA-PF), four well-known relative UVA indices: the UVA-PF/SPF ratio and critical wavelength by European Commission (EC); UVA/UVB ratio by Boots Star Rating system; UVA1/UV ratio by FDA Proposed Ruling and one new relative indices the Spectral Uniformity Index (SUI) by Diffey, were compared before and after sunlight exposure with dose about 42 SEDs. The UVA-PF values before exposure proved a high degree of variation among samples. After exposure only five sunscreens observed UVA protection standard by EC and the same products showed compliance with the first UVA rating by Boots system (three stars). According to the UVA1/UV ratio, except for one product, all sunscreens manifested certain UVA protection level (low, medium or high). In compliance with criteria of new rating proposed by Diffey, exactly all fifteen sunscreens gave some UVA rating exhibited as SUI (low, medium or high). These results mean that the different UVA protection indices can exhibit various data and be confusing for consumer. Photostability of each product was assessed with three indices: the area under curve (Auc) Index for the total UV range, and UVB, UVA, UVA2, UVA1 range separately; the residual effectiveness of in vitro SPF and UVA-PF. All fifteen sunscreens were photostable in the UVB region. Seven products exhibited photoinstability in the total UV range (290-400 nm); all of them contained a combination of the ethylhexyl methoxycinnamate (EHMC) and butyl methoxydibenzoylmethane (BMBM) together with other UV filters. Eight products lacked their stability in the UVA1 range (340-400 nm) thus confirmed that photodegradation of some current sunscreens is primarily problem of this region. The most photoinstability showed sunscreens S1 (EHMC, BMBM and phenylbenzimidazole sulphonic acid) and S6 (EHMC, BMBM, phenylbenzimidazole sulphonic acid and ethylhexyl triazone); Auc-UVA1 Index was 0.15 only. Excellent UVA1 photostability showed sunscreen S8 (EHMC, EHT and methylene bis-benzotriazolyl tetramethylbutylphenol); Auc-UVA1 Index was of 1.00. Three sunscreens showed very good UVA1 photostability (Auc-UVA1 Index ranged from 0.98 to 0.93). The fact that these products applied only in the layer of 0.75 mg cm⁻² were photostable under the sunlight dose, which corresponds to layer of 2 mg cm⁻², is proof of their quality. Comparison of the residual effectiveness of in vitro SPF and UVA-PF values with the Auc-Index showed that methods give a similar ranking of the sunscreens' photostability.

The evaluation of the amount of cis- and trans-urocanic acid in the stratum corneum by Raman spectroscopy.

Urocanic acid (UCA) is a major component in the epidermis which absorbs ultraviolet light (UV) and is isomerized from the trans to the cis form upon UV exposure. This study aimed to evaluate the amounts of cis- and trans-UCA in the stratum corneum (SC) in vivo using Raman spectroscopy. UV damage has previously been investigated by calculating the amount of trans-UCA by fitting Raman spectra. cis-UCA at pH 5.0 was also included in the fitting algorithm in this study. For validation, the SC was stripped from the subjects and the levels of cis- and trans-UCA were measured using high performance liquid chromatography (HPLC). Comparison between these two methods was performed at UV exposure and non-UV exposure sites on the volar forearm of 10 healthy Japanese subjects. Finally, the protective capacity of sunscreen was evaluated by Raman spectroscopy on the volar forearm of 18 healthy subjects. The amount of cis-UCA increased and the amount of trans-UCA decreased after UV exposure when measured by Raman spectroscopy. This was confirmed by HPLC analysis of the SC stripped from the same area of skin used in the Raman measurement. The protection against the increase in the cis-UCA and decrease in the trans-UCA amount after UV exposure by the application of sunscreen products was observed using Raman spectroscopy. The results show this method can be used to measure cis- and trans-UCA levels in vivo.