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The magnitude and quality of UV protection provided by topical sun products have improved considerably over the past three decades. As our knowledge and understanding of sun protection requirements increases, product and testing technologies advance and new sunscreen molecules and technologies become available. The biannual London Sun Protection Co...
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Context 1
... the way to the ideal sunscreen, technology plays a key role. The goal is to reduce the amount of UV radiation that reaches the skin over a broad spectral range. UV filters are the heart of this technology, but also the formulation of the sunscreen is instrumental. The best UV filter combination cannot perform, i.e. spread uniformly and sustainably over the skin, if the sunscreen is formulated poorly. Fig. 2 shows that there are many "UVB filters" covering UVB (290-320 nm) and UVA II (320-340 nm), but now also UVA I (340-400 nm) filters and broad-spectrum UV filters that cover UVB, UVA II and UVA I are available as single molecules 11 except in the USA. Theoretically all the UV filter technology is thus available, but there are still a few reasons why it is or cannot be used everywhere by ...
Citations
... The photon flux in the UV-A is decreased to a much smaller extent, although quantitative estimates are not available. 754 Consequently, sun blockers basically change the wavelengths of the solar irradiance spectrum penetrating the skin, resulting in almost no UV-B, much less UV-A, but unchanged radiation from 380 nm to higher wavelengths ( Figure 1). As a result, the influence that UV-B radiation typically exerts, in both its positive and negative aspects, will be markedly diminished. ...
Endogenous photosensitizers play a critical role in both beneficial and harmful light-induced transformations in biological systems. Understanding their mode of action is essential for advancing fields such as photomedicine, photoredox catalysis, environmental science, and the development of sun care products. This review offers a comprehensive analysis of endogenous photosensitizers in human skin, investigating the connections between their electronic excitation and the subsequent activation or damage of organic biomolecules. We gather the physicochemical and photochemical properties of key endogenous photosensitizers and examine the relationships between their chemical reactivity, location within the skin, and the primary biochemical events following solar radiation exposure, along with their influence on skin physiology and pathology. An important take-home message of this review is that photosensitization allows visible light and UV-A radiation to have large effects on skin. The analysis presented here unveils potential causes for the continuous increase in global skin cancer cases and emphasizes the limitations of current sun protection approaches.
... SWE-Ls were prepared by adding two different concentrations of freeze-dried FV-WE (10 and 20%) and FV-EE (14.1 and 28.2%) to a cream base. Typically, commercial UV-filters are also added in this range (4-25%) [33]. Both FV-WE and FV-EE-enriched lotions were visibly colored. ...
Phlorotannins play a role in biological functions to protect the cells against UV and oxidative damage in brown algae. We hypothesized that these compounds can function as photo-protectors and antioxidants in skin care formulations. Two types of extracts (water (FV-WE) and 67% v/v ethanol (FV-EE)) from Fucus vesiculosus were obtained with a phlorotannin content between 7−14% in dry extract. Exposure to sun light during growth was included as a factor on the phlorotannin content but did not influence the phlorotannin content. However, green colored F. vesiculosus had lower total phenolic content (TPC) (FV-WE = 6.9 g GAE 100 g−1 dw, FV-EE = 7.8 g GAE 100 g−1 dw) compared to those with a yellow/brownish color (FV-WE = 10.4–13.7 g GAE 100 g−1 dw, FV-EE = 11.2–14.0 g GAE 100 g−1 dw). UVA and UVB photo protective capabilities of the extracts through different biological effective protection factors (BEPFs) were evaluated using in vitro methods; the Mansur method for sun protection factor (SPF) and calculation of effective solar absorption radiation (%ESAR) to determine SPF and UVA protection factor (UVA-PF) of the extract and in seaweed enriched lotion. The SPF was negligible, when evaluating FV-WE in lotion (10 and 20% w/w). Moreover, %ESAR of the FV-WE showed SPF and some UVA-PF, but not enough to give sufficient SPF in lotions (10% w/w). It was concluded that the concentration of UV protecting compounds in the extracts was too low to and that further fractionation and purification of phlorotannins is needed to increase the SPF.
... In addition to the effectiveness of the photoprotective substance itself, effectiveness is also directly related to the amount of product and way it is applied by the consumer (Liu et al., 2012). The determination of SPF has been standardized for the specific amount of 2 mg /cm ² , which ensures good coverage and formation of an ideal film on the skin (Binks et al., 2017;Osterwalder, Herzog, 2010). ...
... After about 24 hours of exposure, the regions are evaluated for pigmentation and erythema response. These testing methodologies may vary according to different regulatory agencies and are harmonized by the ISO (International Organization for Standardization) (Manikrao, Laxman, 2016;Osterwalder, Herzog, 2010). ...
... sunscreen should be a neutral density filter [44,45]. The data reported here support the latter view, demonstrating the requirement of broadspectrum protection. ...
Skin pigmentation by solar ultraviolet radiation (UVR; ~295–400 nm) is well established. More recently, visible light (VL; 400–740 nm) has been shown to induce rapid pigmentation. Such pigmentation is thought to be caused by oxidative stress, which has associations with skin cancer and photoageing. However, the UVR-VL boundary region has been less well studied. The lower back of healthy Fitzpatrick skin type II-IV individuals was irradiated with increasing doses of narrow-band 385 nm and 405 nm radiation. Pigmentation change was measured immediately, 6 h and 24 h post-irradiation using two reflectance spectroscopy devices and visual grading. Pigmentation was dose-dependently increased in all skin types and time points for both spectra. Two sunscreens, both labelled SPF 15 and UVA protective in the EU and USA (but with different Boots star rating in the UK, 2* vs 5*) were compared. Their formulations were the same apart from the addition of a new organic filter bis-(diethylaminohydroxybenzoyl benzoyl) piperazine (BDBP) that absorbs between 385 and 405 nm. The product that lacked BDBP provided minimal protection against pigmentation, but its addition provided almost complete protection. This demonstrates the needs to improve photoprotection at the UVR-visible border and for sunscreens to act as neutral density filters.
... These improvements suggest better clinical outcomes, but this has so far not been demonstrated. Although the systematic reviews and meta-analyses pay great attention to the confounding factors, not much attention has been paid to the product's "active principle" -the sunscreen filters, their performance characteristics including their quality (e.g., absorption spectrum, filter stability, or correctness of SPF), and the delivery system (vehicle) [45,[320][321][322]. ...
Since time immemorial, people protected themselves from solar radiation. Limiting time in the sun by seeking shade or wearing clothing was a matter of course. In the early 20th century, tanned skin - a result of exposure to sunlight - was associated with good health. At the same time, however, one also had to protect oneself against the potential of excessive exposure to avoid sunburns. Around 1945, the first sunscreen products for protection against solar radiation became available. In the years to follow and up to the recent past, a vast number of different sunscreen filters were developed and incorporated into a wide variety of product formats. Frameworks regulating filter substances and preparations and methods to characterize sunscreen products' performance parameters were developed. Over the past 50-70 years, the perception regarding the tasks of sunscreen products changed several times. It was initially promoted as a lifestyle product and had the task of preventing sun-related erythema (tan without burn). Later, the prevention of skin cancer was added. Only in recent times, sunscreen products have been increasingly advertised and perceived as beauty and lifestyle products again. Also, the use of sunscreen products for antiaging purposes is now commonplace. The different intended purposes (averting harm and prevention) and the widespread use of topical sunscreen products have promoted many investigations and generated a vast and ongoing need for consumer and patient information and education. In the following review, we analyze and discuss current topics from conflicting areas, such as sun protection products (e.g., ideal sun protection products, sun protection metrics), product safety (e.g., nanoparticulate sunscreen filters, regulatory issues), application in everyday life (e.g., wish to tan, vulnerable cohorts), as well as controversies and future challenges (e.g., risks and benefits of UV radiation).
... However, not all sunscreen compounds to provide sufficient UVA protection. [2] Chalcone derivatives are the components that effectively protect the skin from UVA. [3] The 3,4-dimethoxychalcone (3,4-DMC), a chalcone derivative, had a wide wavelength range, insoluble in water (log P 3.84) and SPF 18.77. [4,5] It has antioxidant activity, antifungal, [6] and anticancer. ...
UltravioletA (UVA) rays with an intensity of 95% can induce skin cancer due to the activation of reactive oxygen species (ROS). The 3,4-dimethoxychalcone (3,4-DMC) chalcone derivative has a wide wavelength, antioxidant activity, presumed has activity as sunscreen (UVA rays). Topical delivery of water-insoluble 3,4-DMC with log P 3.84 required capable, cream formulation was chosen because it was suitable for application this chemical sunscreen. This study aims to obtain the optimal formulation of 3,4-DMC in a sunscreen cream dosage form as a UVA-protection factor (UVA-PF). This study involves experimental design. The cream 3,4-DMC was evaluated physically for 4 weeks by measuring pH, viscosity, spreadability, adhesion, centrifugation, freeze-thaw, photostability, UVA-PF used Tranpore TM tape, and skin irritation test on animals. The result obtained was evaluated statistically using ANOVA (SPSS version 24). The ratio UVA/UVB value of 3,4 DMC sunscreen cream having 5 stars (*****) for all concentrations, shows the product in this study can be used as an anti-UVA agent in sunscreen cream cosmetic products. The stability of the cream has pH 4.0-4.2; spreadability 5-6 cm; viscosity 4.470-5.763; and adhesion <1 s. Freeze-thaw and centrifugation were known did not affect the stability due to the absence of separation. There was no wavelength shift in the photostability test and no skin irritation due to in vivo examination using New Zealand rabbits. The 3,4-DMC as a new agent in conventional sunscreen cream dosage form has good properties as a protection against UVA rays.
... According to the data rejection criteria of ISO 24444:2010, 25 subjects with "no erythema at any exposed subsites" and "all subsites showing erythema" were excluded from the final data Compliance with appropriate sunscreen application is known to be the most important factor for sufficient UV protection. 29 Inadequate application can increase the risk of UV exposure, as people who apply sunscreen may spend longer outside as they believe their sunscreen will effectively protect them. 23 There is still a long way toward the proper sunscreen use, and it must not be bothersome or inconvenient for people to comply well. ...
Background:
The proper application of sunscreen is important to ensure protection of the skin against ultraviolet (UV) damage. Sunscreens are used in various ways in real world situations, which alters their UV protection efficacy. In this study, we simulated typical consumer use of sunscreen, which is often sequentially covered with facial makeup, in a laboratory study.
Methods:
We compared the sun protection factors (SPF) of sunscreen and makeup products after consecutive layering of the products.
Results:
The SPF of each sunscreen and makeup product was dramatically lower than stated on the label upon application of a typical amount used by a consumer, which is lower than recommended. For high-SPF products, the drop in effective protection was proportionally greater than those for the low-SPF products upon application of lower doses. However, layering sunscreen and makeup products greatly increased the effective SPF compared with that achieved by single application of each product, even when the amount of each product used was below the recommended level.
Conclusion:
Layering sunscreen with makeup may compensate for insufficient sunscreen application in real-life conditions by providing an additional source of UV protection and improving the homogeneity of coverage. Our results suggest that recommending consecutive application of sunscreen and makeup products may be a practical and useful approach to improving UV protection that would not require additional steps in the facial care routines of many individuals.
... In the past, numerous therapies to prevent or treat EPP symptoms have been tried and studied. As sunscreen only blocks UVA and UVB and does not block light in the visible spectrum such as blue light (>400 nm), conventional topical sunscreens are not effective in EPP [19]. Pain medication and stronger analgesics like morphine are notoriously ineffective to give pain relief during a phototoxic reaction [7]. ...
Introduction
In erythropoietic protoporphyria (EPP), an inherited disorder of heme biosynthesis, accumulation of protoporphyrin IX results in acute phototoxicity. EPP patients experience severe burning pain after light exposure, which results in a markedly reduced quality of life (QoL). Afamelanotide is the first effective approved medical treatment for EPP, acting on melanocortin-1 receptors. This article aims to review afamelanotide.
Areas covered
: This review summarizes the chemical properties, pharmacokinetics, safety, preclinical and clinical data on afamelanotide in EPP,and post-marketing surveillance. PubMed search, manufacturers’ websites and relevant articles used for approval by authorities were used for the literature search.
Expert opinion
Afamelanotide is an α-melanocyte stimulating hormone analogue. It can activate eumelanogenesis without exposure to UV radiation. Clinical studies in EPP showed that afamelanotide treatment significantly increased exposure to sunlight and QoL. In our clinical experience afamelanotide treatment is much more effective in clinical practice than demonstrated in clinical trials and should be made available for all EPP patients meeting inclusion-criteria. The 60-day interval period was not based on effectiveness studies, and therefor for some of the patients the maximum of four implants per year with the 60-day interval is insufficient. Afamelanotide is well tolerated; common adverse events were headache, fatigue and nausea.
... Many factors must be achieved to develop an ideal sunscreen, such as broad-spectrum photoprotection (UVA and UVB; 290-400 nm) (Osterwalder and Herzog 2010), safety, photostability, nice sensory and tactile profiles, and minimum skin penetration (Gilbert et al. 2013;Jansen et al. 2013). Sunscreen active ingredients comprise UV filters, molecules or molecular complexes capable of absorbing, reflecting or dispersing UV radiation, depending on their nature. ...
... High concentrations of inorganic UV filters impact the sensory attributes of the product, such as ease of distribution and unpleasant white marks on the skin. As a strategy to avoid this effect, nanoparticle form of inorganic UV filters is preferred rather than microparticle ones (Osterwalder and Herzog 2010). The International Cooperation on Cosmetic Regulation (ICCR) describes a cosmetic nanomaterial as an insoluble, specifically manufactured ingredient with one or more dimensions ranging from 1 to 100 nm in the final formulation. ...
... The SPF is the metric for sunscreen protection based on minimal erythema dose (MED), which can be defined as "the smallest UV dose that produces perceptible redness of the skin (erythema) with clearly defined borders at 16 to 24 h after UV exposure" (Osterwalder and Herzog 2010). Sunscreen is applied to the test sites at an amount of 2 mg/cm 2 and SPF is then calculated as the ratio of MED on sunscreen protected skin to that on unprotected skin (Gilbert et al. 2013). ...
Although sunlight provides several benefits, ultraviolet (UV) radiation plays an important role in the development of various skin damages such as erythema, photoaging, and photocarcinogenesis. Despite cells having endogenous defense systems, damaged DNA may not be efficiently repaired at chronic exposure. In this sense, it is necessary to use artificial defense strategies such as sunscreen formulations. UV filters should scatter, reflect, or absorb solar UV radiation in order to prevent direct or indirect DNA lesions. However, the safety of UV filters is a matter of concern due to several controversies reported in literature, such as endocrine alterations, allergies, increased oxidative stress, phototoxic events, among others. Despite these controversies, the way in which sunscreens are tested is essential to ensure safety. Sunscreen regulation includes mandatory test for phototoxicity, but photogenotoxicity testing is not recommended as a part of the standard photosafety testing program. Although available photobiological tests are still the first approach to assess photosafety, they are limited. Some existing tests do not always provide reliable results, mainly due to limitations regarding the nature of the assessed phototoxic effect, cell UV sensitivity, and the irradiation protocols. These aspects bring queries regarding the safety of sunscreen wide use and suggest the demand for the development of robust and efficient in vitro screening tests to overcome the existing limitations. In this way, Saccharomyces cerevisiae has stood out as a promising model to fill the gaps in photobiology and to complete the mandatory tests enabling a more extensive and robust photosafety assessment. ARTICLE HISTORY
... protection [4][5][6]. A range of artificial sunscreens has therefore been developed and incorporated into skin care cosmetics [7,8]. ...
The increasing awareness of the adverse effects of exposure to UV radiation in combination with the conclusion that presently employed sunscreen agents are far from optimal has led to the need to develop novel UV filters with improved absorption and stability characteristics. Studies of natural sunscreens can provide fundamental insight into strategies to come to a rational design of such filters. Here, we use high-resolution laser spectroscopic methods to study the spectroscopy and excited-state dynamics of methyl sinapate, a prominent plant sunscreen derivative. We find that our experimental approach based on two-color Resonance Enhanced Two-Photon Ionisation spectroscopy enables us to observe a hitherto not observed decay pathway leading to a long-lived state, albeit with a significantly lower yield than in cinnamates and coumarates. In combination with extended excitation spectra and employing the results of quantum chemical calculations a comprehensive picture is obtained of the internal conversion pathways that are accessible to this compound. Similar high-resolution studies on clusters of methyl sinapate with water show how solvent-solute interactions affect the electronic structure and excited-state decay dynamics of the chromophore.
