Sunscreens Part 1: Mechanisms and Efficacy

As our knowledge of the harmful effects of ultraviolet radiation continues to evolve, sunscreen remains an integral part of a comprehensive photoprotection strategy against multiple endpoints of ultraviolet-mediated damage. Part 1 of this review covers sunscreen active and additive ingredient properties, mechanisms of action and gaps in coverage. Following an overview of sunscreen's efficacy in protecting against sunburn, photocarcinogenesis, photoaging, pigmentary disorders, and idiopathic photodermatoses, we highlight considerations for product use and selection in children and individuals with skin of color.

Assessment of prevalence of sunscreen use and related practices among people living in Saudi Arabia: A cross-sectional survey-based study

BACKGROUND

The use of sunscreen significantly reduces the risk of skin cancer and helps maintain skin health; however, improper use can decrease its effectiveness. This study aimed to investigate the prevalence and factors associated with sunscreen use in Saudi Arabia as well as identifying areas of weakness in sunscreen practices.

METHODS

A cross-sectional survey-based study was conducted with a diverse population sample in Saudi Arabia. Participants were asked about their sunscreen usage habits, motivations, and knowledge of proper application techniques. Demographic information, including age, gender, and skin type, were also collected.

RESULTS

A total of 2321 individuals participated in the study. More than two-thirds of the participants reported using sunscreen either always, regularly, or often, primarily to maintain a light skin color and prevent skin cancer. Factors associated with sunscreen use included younger age (18-40 years old), female gender, history of sunburn, and fair skin. Despite the majority reporting healthy sun exposure habits, several shortcomings were identified in sunscreen practices, including incorrect application and suboptimal reapplication frequency.

CONCLUSION

While sunscreen use is common among the study population, there is a need for improved education on proper application techniques. National awareness campaigns, especially those utilizing popular social media and digital platforms in Saudi Arabia, should focus on disseminating accurate sunscreen use guidelines to maximize sun protection and skin health.

Sunscreen compound benzophenone-3 and its relationship with white blood cell counts

BACKGROUND

Evidence from animal models suggests a role for the organic ultraviolet filter benzophenone-3's (BP-3) on white blood cells (WBCs). However, BP-3's effect on WBCs in humans is unknown.

MATERIALS AND METHODS

We used National Health and Nutrition Examination Survey data from 2003 to 2016. We included participants >6 years with data on urinary BP-3, urinary creatinine, and WBC count. Quintiles of urinary creatinine-normalized BP-3 (CnBP-3) levels were used in linear regression models adjusting for age, gender, race, body mass index (BMI), smoking status, education level, family income to poverty threshold ratio, survey cycle, and season.

RESULTS

Of the 16 959 participants, 8564 (50.5%) were females, 6602 (38.9%) were White, and 3870 (22.8%) were Black. The mean (standard deviation) age was 37.6 (22.7) years, BMI was 26.8 (7.40) kg/m2, WBC count was 7.22 (2.53) × 109/L, neutrophil count was 4.15 (1.86) × 109/L, and lymphocyte count was 2.25 (1.33) × 109/L and median (interquartile range) of CnBP-3 was 12.1 (44.9) µg/gm. The highest quintile of CnBP-3 was associated with significantly lower WBC and neutrophil counts compared to the lowest quintile of CnBP-3 (Δ quintiles = -137 × 106/L, 95% CI: -249 to -24, p = 0.02 and = -177 × 106/L, 95% CI: -323 to -30, p = 0.02, respectively). In contrast, we did not observe a difference in lymphocyte count between the lowest and highest quintiles of CnBP-3 in unadjusted or adjusted analyses.

CONCLUSION

We found an inverse relationship between BP-3 levels and WBC and neutrophil counts, and not with lymphocyte count. Further research is needed to confirm our findings.

mori) Silk Fibroin Microspheres for Developing Biosafe Sunscreen

Sunscreens play a crucial role in protecting the skin from ultraviolet (UV) damage. However, present commercial sunscreens have a tendency to generate free radicals in the UV window, resulting in serious inflammatory responses and health problems. In this study, we demonstrate that silk fibroin microspheres (SFMPs) assembled from regenerated silk fibroin (SF) could scavenge free radicals while preventing UV irradiation and thus present a promising sunscreen. The SFMP reflected more UV light than SF and presented a higher stability than that of organic commercial sunscreens. In vitro analysis proved that SFMP could more efficiently scavenge the hydroxy radical and reduce the intracellular reactive oxygen than titanium dioxide (TiO2). In vivo experiments exhibited that SFMP provided stronger skin protection against UV irradiation than commercial sunscreens and TiO2. Furthermore, SFMP treatment significantly inhibited the skin inflammatory response. This work suggests that the SFMP has great potential to be developed into a biosafe sunscreen.

Sun Exposure and Usage of Sun Protection: Knowledge, Perception and Practice among University Students

Background

Exposure to the sun is vital for the body but is associated with problem ranging from pigmentation to cancer. Therefore, knowledge about protective measures is critical. This study aims to assess undergraduate students' knowledge, perception and practices towards the adverse effects of sun exposure and the usage of sun-protective measures.

Methods

A cross-sectional study was conducted between 1 September 2022 and 20 September 2022 using a web-based questionnaire. Undergraduate students from medical and non-medical colleges in Iraqi universities participated in this study. Descriptive and inferential statistics and logistic regression were performed to analyse the data.

Results

A total of 655 students participated in this study. The knowledge level of more than one-half of the students (53%) was inadequate. Approximately three-quarters of the study sample used sunscreens products. Skin type was the main factor in choosing the appropriate sunscreen product. Media and advice from specialists were the main factors affecting participants' usage of sunscreens. Gender (females), college (medical), year(s) of study (sixth), residence (urban), daily sun exposure (1 h-3 h) and less-than-normal vitamin D levels were found to be significantly associated with better knowledge (P-value < 0.05). Age, gender, being a student in medical colleges and not knowing vitamin D levels were found to be significant predictors of participants' knowledge.

Conclusion

The low level of knowledge reported among the participants' calls for more attention from health authorities in educating the public about the harmful effects of sun exposure and the importance of adopting protective measures.

Does Male Skin Care Content on Instagram Neglect Skin Cancer Prevention?

This research letter assesses male skin care content on social media in order to bring to light the lack of content regarding skin cancer prevention posted on Instagram for male audiences.

Photoprotective effect of topical treatment with Lopezia racemosa extract against deleterious UVB irradiation effects in the skin of hairless mice

Lopezia racemosa is known as a "mosquito flower or perlilla." It is commonly found in corn crops. In traditional Mexican medicine, this plant is used to treat stomach cancer and urinary tract infections. Likewise, compounds and extracts isolated from plants have shown cytotoxic and anti-inflammatory effects. The objective of this study was to evaluate the photochemoprotective effect of topical treatment with the methanolic extract of L. racemosa (MELR) as a photochemoprotective agent against the harmful effects of UV irradiation (UVR) on a bacterial model and hairless mice. The MELR components were separated and analyzed via HPLC-UV-ESI-MS. Antioxidant activity was evaluated by the ability of MERL to scavenge DPPH and ABTS free radicals and by its FRAP capacity. The toxicity of MELR was evaluated in keratinocyte cultures. The photoprotective capacity of MELR was assessed through challenge experiments using models with bacteria and hairless CD1 et/et mice; cytokines related to the damage caused by UVR were also measured. In the methanolic extract of L. racemosa, five metabolites were detected and identified: two isomers of quercetin 6-C glycoside, orientin, quercetin 3-(6″-acetylglycoside) and quercetin 3-(6″-galloylglycoside) 7-(2,3-dihydroxytetrahydro-2H-pyran-4-yl acetate). MELR exhibited DPPH and ABTS radical scavenging properties, in addition to Fe ion reducing activity. MELR showed a photoprotective effect against UVB radiation-induced death in Escherichia coli bacteria. At the histological level, topical treatment of CD-1 et/et mice with MERL reduced the damage caused by UVR. Quantification of interleukins in the blood of mice revealed that the expression of IL-12 was greater in the control group treated with ultraviolet radiation than in the group protected with MELR. The methanolic extract of L. racemosa has photochemoprotective properties.

Anti-UV Microgel Based on Interfacial Polymerization to Decrease Skin Irritation of High Permeability UV Absorber Ethylhexyl Methoxycinnamate

Ethylhexyl methoxycinnamate (EHMC) is frequently employed as a photoprotective agent in sunscreen formulations. EHMC has been found to potentially contribute to health complications as a result of its propensity to produce irritation and permeate the skin. A microgel carrier, consisting of poly(ethylene glycol dimethacrylate) (pEDGMA), was synthesized using interfacial polymerization with the aim of reducing the irritation and penetration of EHMC. The thermogravimetric analysis (TGA) indicated that the EHMC content accounted for 75.72% of the total composition. Additionally, the scanning electron microscopy (SEM) images depicted the microgel as exhibiting a spherical morphology. In this study, the loading of EHMC was demonstrated through FTIR and contact angle tests. The UV resistance, penetration, and skin irritation of the EHMC-pEDGMA microgel were additionally assessed. The investigation revealed that the novel sunscreen compound, characterized by limited dermal absorption, had no irritant effects and offered sufficient protection against ultraviolet radiation.

A new eco-friendly and water-resistant sunscreen agent: Lecithin-based multilamellar liposomes

BACKGROUND

UV skin exposure is an important matter of public health, as the worldwide rising prevalence of skin cancers indicates. However, a wide majority of commercially available sunscreens are responsible for ocean ecosystem damages such as coral reef degradation and phytoplankton mortality.

AIMS

To answer the urge for new eco-friendly UV filters, we studied the use of lecithin-based multilamellar liposomes (MLLs) of controlled size and elasticity as a bio-sourced and biodegradable alternative to classic sunscreens. These parameters control allows different skin layers targeting.

METHODS

The performance of two different MLLs compositions and a commercially available SPF50+ water-resistant liposomal sunscreen was compared on skin explants. SC-MLLs target the stratum corneum and Epi-MLLs the whole epidermis. Preparations were applied prior to skin irradiation. Their efficiencies were evaluated histologically (hematoxylin and eosin staining plus cyclobutane pyrimidine dimer [CPD] immunostaining) and by skin barrier quality assessment (trans-epithelial electrical resistance). Adhesiveness to the skin was also investigated.

RESULTS

Altogether, ex vivo results indicate MLLs offer a solar protection as effective as a SPF50+ water-resistant liposomal sunscreen but with a better skin adhesiveness and an improved skin barrier function.

CONCLUSION

Lecithin-based MLLs of controlled physicochemical parameters can be used as a new eco-friendly and water-resistant agent for solar protection. The stratum corneum targeted action of SC-MLLs appears to be more interesting, as SC-MLLs exhibit an overall better performance than Epi-MLLs at a lower cost. The skin barrier improvement showcased could be of interest to people suffering from dry skin or skin barrier impairment related disease.

Sunscreen Safety and Efficacy for the Prevention of Cutaneous Neoplasm

Sunscreen is widely used for ultraviolet radiation protection. Studies validate sun protection factors (SPFs) to prevent ultraviolet (UV)-induced skin changes such as melanoma and squamous cell carcinoma (SCC). Few studies examine sunscreen's impact on endocrine and immune system dysregulation, the production of radical oxygen species, and whether the ingredients deteriorate under prolonged exposure. We present an investigation of sunscreen labels and how ingredients impact sun safety and human health. A review of the literature was conducted using Embase and PubMed to examine sunscreen safety, efficacy, and use to prevent UV-induced skin damage. Increasing sunscreen reapplication, wearing protective clothing, and limiting exposure can reduce the incidence of skin cancer. Inorganic sunscreens form barriers to block UV light, but without titanium dioxide (TiO2), they may not be advantageous due to their low UVA protection. Organic sunscreens absorb into the skin and provide a better feeling after application. Octocrylene and avobenzone are stable and provide UVA and UVB protection with minimal adverse effects. Oxybenzone is harmful to the neuroendocrine system and should be avoided. Titanium dioxide works for broad-spectrum UV protection and offers minimal adverse effects. Octocrylene and avobenzone are organic sunscreen ingredients that also provide a better feeling on the skin after application, which enables higher rates of use. Oxybenzone should be avoided.

Knowledge, Attitude, Reception, and Preventive Practices Towards Skin Photoaging Among the General Population in Jazan, Saudi Arabia

Introduction Skin photoaging is caused by prolonged exposure to sunlight, particularly ultraviolet rays (UV). High cumulative levels of UV radiation may cause burning, photoallergic or phototoxic reactions, pigmentary changes, photoaging, and even immunosuppression and skin cancers. Therefore, this study aims to assess knowledge, attitude, reception, and preventive practices towards skin photoaging among the Jazan general population in Saudi Arabia and its determinants. Methods A descriptive cross-sectional study was conducted among the general population of Jazan, Saudi Arabia, who were aged 18 years and above and agreed to participate in the study. The calculated minimum sample size was 385. An online, semi-structured, self-administered questionnaire was distributed conveniently in Google Forms through social media platforms. It included four sections: The first section was about sociodemographic characteristics. The second section assessed the smoking, exercise, and healthy diet behavior of participants and the use of sunscreen. The third section assessed the knowledge regarding the photoaging process and its preventive measures utilization using three-point Likert scale questions. The fourth section assessed attitudes towards the photoaging process and its preventive measures through three-point Likert scales. Results The study included 452, of which 243 (53.76%) were aged 18-30 years, 258 (57.08%) were females, and 272 (60.18%) had white skin color. Approximately 417 (92.26%) were nonsmokers. Sixty-eight percent (372) spent 1-3 hours in the sun. Social media was the primary source of information on photoaging 81 (17.92%). Around 234 (51.77%) defined photoaging correctly. Regarding sunscreen usage, 58 (12.83%) always use sunscreen, and 177 (39.16%) never use it. However, 191 (42.26%) recognized the correct sunscreen application. Approximately 233 (51.5%) and 240 (53.1%) of respondents had fair knowledge and a positive attitude regarding photoaging and sunscreen use. Being female, pursuing university and postgraduate education, and taking information on photoaging from a physician were linked to a higher knowledge of photoaging (p<0.05). Participants who never use sunscreen had lower knowledge than those who always use it (p<0.001). None of the demographic factors was associated with the attitude towards sunscreen use (p>0.05). Conclusion There is a substantial gap in knowledge and preventive practices related to skin photoaging among the Jazan general population in Saudi Arabia. Gender, education level, and information sources influence knowledge levels. Targeted educational interventions are needed to enhance awareness and promote healthier practices, particularly sun exposure and photoaging prevention.

Multi-omics approach to understand the impact of sun exposure on an in vitro skin ecosystem and evaluate a new broad-spectrum sunscreen

A reconstructed human epidermal model (RHE) colonized with human microbiota and sebum was developed to reproduce the complexity of the skin ecosystem in vitro. The RHE model was exposed to simulated solar radiation (SSR) with or without SPF50+ sunscreen (with UVB, UVA, long-UVA, and visible light protection). Structural identification of discriminant metabolites was acquired by nuclear magnetic resonance and metabolomic fingerprints were identified using reverse phase-ultra high-performance liquid chromatography-high resolution mass spectrometry, followed by pathway enrichment analysis. Over 50 metabolites were significantly altered by SSR (p < 0.05, log2 values), showing high skin oxidative stress (glutathione and purine pathways, urea cycle) and altered skin microbiota (branched-chain amino acid cycle and tryptophan pathway). 16S and internal transcribed spacer rRNA sequencing showed the relative abundance of various bacteria and fungi altered by SSR. This study identified highly accurate metabolomic fingerprints and metagenomic modifications of sun-exposed skin to help elucidate the interactions between the skin and its microbiota. Application of SPF50+ sunscreen protected the skin ecosystem model from the deleterious effects of SSR and preserved the physiological interactions within the skin ecosystem. These innovative technologies could thus be used to evaluate the effectiveness of sunscreen.

Efficacy of ceramide-containing sunscreen on skin barrier

BACKGROUND

UV rays not only cause oxidative damage to the skin, but also damage its barrier function. The use of sunscreen is crucial in preventing skin from UV radiation, but it may have an impact on the function of the skin barrier. While much research has focused on the protective effects of sunscreen against UV oxidative damage, little is known about the impact of daily sunscreen use on the skin barrier.

OBJECTIVE

This study mainly investigated the changes in skin barrier function of volunteers (including those with sensitive skin) before and after using a ceramide-containing sunscreen.

METHODS

A total of 60 volunteers used SPF30 sunscreen containing ceramide every morning. Using non-invasive methods to detect skin barrier changes in TEWL, hydration, facial redness based on VISIA-CR image, and Erythema index (EI) value after 4 weeks of using ceramide-containing sunscreen. Adverse reactions were also assessed.

RESULTS

After 4 weeks of using ceramide-containing sunscreen, significant reductions were observed in skin redness with both an 11.89% decrease in a* value and a 5.68% decrease in skin EI, while there was also a significant decrease in transepidermal water loss (TEWL) with a reduction of 22.96%, and a significant increase in skin hydration with a 21.96% increase in the moisture content of the stratum corneum. No adverse events occurred during the entire testing process.

CONCLUSION

Daily application of ceramide-containing sunscreen can increase skin hydration while enhancing the function of the skin barrier.

Smart Watches Lack Skin Smarts: Current and Future Dermatologic Applications in Device Metrics

INTRODUCTION

Smartwatches have proven life-saving in medical specialties such as cardiology. Smartwatches actively warn us of arrhythmia risk and loud noise exposure. However, dermatologic health metrics are rarely monitored, and users are never alerted of potential skin health issues. Furthermore, the role of these devices within dermatology has not been evaluated in the literature. This study aims to analyze the current data points monitored by smartwatches and discuss potential adaptations to support dermatologic patient education and improve clinical management.  Methods: The top three smartwatches per global market share were identified and analyzed to determine the health data points they monitor and the alerts they provide. These data points were grouped and compared based on their corresponding body systems.  Results: Cardiovascular health comprises the highest percentage of data points collected with an average of 41% while dermatologic health averaged only 11%.  Conclusion: Dermatology is grossly underrepresented in current smartwatch devices. There is an important need to expand the dermatologic health metrics tracked by adapting existing smartwatch technology. From proactive cancer prevention to disease-specific reactive interventions, smartwatches can play a significant role in improving dermatological health and reducing healthcare costs.

Reducing Gut Dissolution of Zinc Oxide Nanoparticles by Secondary Microplastics with Consequent Impacts on Barnacle Larvae

The environmental impact of sunscreen is a growing concern, yet the combined effects of its components on marine animals are poorly understood. In this study, we investigated the combined effects of sunscreen-extracted zinc oxide nanoparticles (nZnO) and microplastics (MPs) on the development of barnacle larvae, focusing on the different roles played by primary microplastics (PMPs) and secondary microplastics (SMPs) generated through the phototransformation of PMPs. Our findings revealed that a lower concentration of nZnO (50 μg/L) enhanced molting and eye development in barnacle larvae, while a higher concentration (500 μg/L) inhibited larval growth. Co-exposure to PMPs had no significant effect on larval development, whereas SMPs mitigated the impact of nZnO by restricting the in vivo transformation to ionic Zn. Accumulated SMPs reduced gut dissolution of nZnO by up to 40%, lowering gut acidity by 85% and buffering the in vivo dissolution of nZnO. We further identified a rough-surfaced Si-5 fragment in SMPs that damaged larval guts, resulting in decreased acidity. Another Si-32 resisted phototransformation and had no discernible effects. Our study presented compelling evidence of the impacts of SMPs on the bioeffect of nZnO, highlighting the complex interactions between sunscreen components and their combined effects on marine organisms.

A narrative review of the impact of ultraviolet radiation and sunscreen on the skin microbiome

BACKGROUND

The human skin microbiome is a dynamic ecosystem that plays an important role in skin health. The skin microbiome has been implicated in numerous diseases, and our knowledge surrounding it continues to evolve. A better understanding of the interactions between the environment and the skin microbiome will lead to improvements in skin health.

METHODS

This article reviews the published literature surrounding the impact of ultraviolet radiation (UVR) and sunscreen on the skin microbiome.

RESULTS

Skin microbes are differentially impacted by UVR, and alterations in the microbiome can be detected following UVR exposure. These changes are related to direct bactericidal effects, alterations in the cutaneous metabolome, and changes in the cutaneous immune system. UV filters used in sunscreen have been shown to have bactericidal effects, and many compounds used in sunscreen emulsions can also negatively impact cutaneous microbes.

CONCLUSION

A healthy microbiome has been shown to produce compounds that help protect the skin from UVR, and sunscreen has the potential to reduce the diversity of the skin microbiome. This indicates that designing sunscreen products that both provide protection against UVR and preserve the skin microbiome may offer additional benefits to skin health when compared with traditional sunscreen products.

Evaluation of social knowledge on photoprotection and its relationship with education and age in a Polish seaside town during summer holidays

OBJECTIVE

This survey aimed to evaluate knowledge of photoprotection among individuals from a random group in a resort town in Poland, Kołobrzeg, and explore the correlation between their knowledge and demographics like age, gender, education, and residence.

METHODS

An anonymous survey was conducted among a diverse group. This population comprised individuals from various backgrounds: health spa patients undergoing treatments, therapies and medical appointments, guests visiting the resort for leisure, passersby, and staff working at the spa and recreational facilities. The survey was designed by authors, encompassed 16 questions about knowledge on photoprotection, sunscreen use and related topics, and gathered demographic data. Responses from 142 individuals were statistically analyzed using PQStat Software.

RESULTS

Only 7.7% use sunscreen all year-round. The majority apply sun protection factor (SPF) creams on sunny days or with prolonged sun exposure. Over half of the respondents (53.5%) are aware when to apply sunscreen but 43% reapply it less than every 4 h. 25.4% do not reapply at all. 38.7% think protection provided by higher SPF means longer sun exposure time. Over 50% believe SPF 30 offers double the protection of SPF 15. Almost half (46.8%) use extra sun protection, like sunglasses or hats. Significant correlations exist between education/age and certain survey responses.

CONCLUSIONS

The findings emphasize the urgency to improve photoprotection knowledge in the Polish population, particularly regarding the year-round harmful solar effects and the correct use of sun protection products.

Evaluation of the protection of sunscreen products against long wavelength ultraviolet A1 and visible light-induced biological effects

BACKGROUND

Long wavelength ultraviolet-A1 in combination with visible light induces hyperpigmentation, particularly in dark-skin phototypes. This study evaluated the efficacy of four sunscreen formulations in protecting against VL + UVA1 (370-700 nm).

METHODS

The test products (A-D) were applied to the back of 12 volunteers, then irradiated with 320 J/cm2 VL + UVA1 (3.5% UVA1 [370-400 nm]). Immediately after irradiation, and at Days 1, 7, and 14, erythema and pigmentation were assessed by investigator global assessment (IGA), colorimetry (Δa* and ΔITA) and diffuse reflectance spectroscopy (DRS)-measured relative dyschromia (area under the curve AUC). Control areas were irradiated without sunscreen.

RESULTS

Product D, containing titanium dioxide 11%, iron oxides 1%, and antioxidants, provided the highest and most consistent protection. Compared with unprotected irradiated control, it had statistically significantly less erythema on IGA, DRS (Δoxyhemoglobin), and colorimetry (Δa*) at Day 0; less pigmentation on IGA at all time points, on DRS (relative dyschromia) at Days 7 and 14, and on colorimetry (ΔITA) at Day 0. Product B, containing zinc oxide 12% plus organic UV filters, iron oxides 4%, and antioxidants, also showed some efficacy.

CONCLUSION

Of the sunscreens tested, the tinted products provided better protection against VL + UVA1 than the non-tinted products. Since the product with 1% iron oxides was superior to the product with 4% iron oxides, further studies are needed to evaluate whether iron oxide content correlates with better protection.

Positive and ecobiological contribution in skin photoprotection of ectoine and mannitol combined in vivo with UV filters

BACKGROUND

Chronic exposure to ultraviolet (UV) irradiation causes immunosuppression, photoaging, and carcinogenesis by induction of a cascade of skin damages. Sunscreens currently on the market are not absorbing UV rays uniformly throughout the full UV range, high sun protection factor (SPF) sunscreens absorb most of UVB rays but are less effective in absorbing the UVA part of the spectrum. In the context, one approach could consist of preserving the skin natural resources and mechanisms, which is the foundation of the ecobiological approach, by combing UV filters and antioxidants to enhance their photoprotective effect.

METHODS

First, the photoprotection properties of ectoine and mannitol association were characterized by the quantification of glutathione, reactive oxygen species, and double-stranded DNA breaks and by the epidermal Langerhans cells functionality. Second, the protection of squalene oxidation, catalase activity, and trans-urocanic acid (UCA) by the ectoine and mannitol association combined or not with SPF30 UV filters was assessed in vivo via non-invasive skin samplings in 10 subjects on irradiated areas.

RESULTS

Using in vitro irradiated skin cell models, we demonstrated that this association significantly preserved intracellular glutathione levels, reduced DNA strand breaks induced by oxidative stress, and maintained Langerhans cell functionality. In vivo this association combined with UV filters presented significantly higher protection of three natural defense systems altered by UV compared to UV filters alone: squalene oxidation, catalase activity, and preservation of trans-UCA.

CONCLUSION

This study demonstrates the ecobiological potential of combining UV filters with biological protection to increase skin photoprotection provided by specific active ingredients with antioxidative and immunosuppressive properties.

Effect of Ag and Ni-Doped Cerium Oxide Nanoparticles on the Formation of ROS and Evaluation as an Alternative Physical Sunscreen Material

CeO2 nanoparticles (nanoceria) were proposed as an alternative physical sunscreen agent with antioxidant properties and comparable UV absorption performance. Green synthesis of nanoceria with Ag and Ni dopants resulted in doped nanoceria with lower catalytic activity and biologically-safe characteristics. The doped nanoceria was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Rancimat Instrument, and UV-Vis Spectrophotometer for SPF (Sun Protection Factor) determination. XRD and TEM analysis showed that nanoceria had been successfully formed in nanoscale-sized with a change in crystallite size due to the crystal defect phenomenon caused by dopant addition. While the Rancimat test and band gap energy analysis were conducted to evaluate the oxidative stability and reactive oxygen species formation, it was confirmed that dopant addition could decrease catalytic activity of material, resulting in Ni-doped Ce with a longer incubation time (11.81 h) than Ag-doped Ce (10.58 h) and non-doped Ce (10.30 h). In-vitro SPF value was measured using the thin layer technique of sunscreen prototype with Virgin Coconut Oil (VCO)-based emulsion, which yielded 10.862 and 5.728 SPF values for 10% Ag-doped Ce and 10% Ni-doped Ce, respectively. The dopant addition of nanoceria could reduce catalytic activity and give a decent in vitro UV-shielding performance test; thus, Ag and Ni-doped nanoceria could be seen as promising candidates for alternative physical sunscreen agents.

Investigation on the Validity of in vitro Sun Protection Factor and Ultraviolet-A Protection Factor Evaluation Method for Sunscreen Samples

Factors affecting the in vitro Sun Protection Factor (SPF) and Ultraviolet-A Protection Factor (UVA-PF) of sunscreens were analyzed for verifying the validity and reliability of the ISO24443 evaluation method. UV absorbance measurements by different spectrophotometers did not lead to the large difference in in vitro SPF/UVA-PF, although the UV absorbance determined by each spectrophotometer exhibited relatively large difference when it was larger than 2. On the other hand, relatively large difference was found in in vitro SPF/UVA-PF by utilizing European Cosmetic and Perfumery Association (Colipa) 1994 or UV-solar simulated radiation (UV-SSR) for the spectral irradiance. Appropriateness of employing the coefficient of adjustment for the determination of in vitro UVA-PF was also found to be reexamined.

Possible Explanations for Rising Melanoma Rates Despite Increased Sunscreen Use over the Past Several Decades

The incidence of cutaneous melanoma continues to rise despite the increased use of sunscreens within the last several decades. Some research even suggests that the use of sunscreen is associated with increased rates of melanoma. Given the aggressive, and often deadly, nature of cutaneous melanoma, the aim of this communication is to better elucidate the relationship between sunscreen use and melanoma development and if there are other preventative measures to be aware of. A search was performed to identify the studies that have investigated melanoma development in individuals who used sunscreen and those who did not. Study limitations and possible confounding variables were identified, which guided a subsequent search to determine what data were available to support that these limitations and confounding variables may explain the perplexing association between sunscreen use and melanoma development. Five hypotheses were generated, which were related to increased awareness and reporting, the relationship between sunscreen use and the duration of sun exposure, the importance of broad-spectrum protection, and the effect of sunscreen on reactive oxygen species formation. The main conclusion is that more recent studies that control for confounding variables are required to determine the true effect of adequate broad-spectrum sunscreen use today on the development of melanoma.

The Impact of WhatsApp as a Health Education Tool in Albinism: Interventional Study

BACKGROUND

Oculocutaneous albinism is a congenital disorder that causes hypopigmentation of the skin, hair, and eyes due to a lack of melanin. People with albinism are at increased risk of developing skin complications, such as solar keratosis and skin cancers, leading to higher morbidity. As education is crucial in managing albinism, leveraging information technology, such as WhatsApp, can provide an effective intervention for digital health education.

OBJECTIVE

This study aims to assess the impact of WhatsApp as a tool for providing health education among people with albinism.

METHODS

The design of the study was interventional. The intervention consisted of weekly health education sessions conducted in a WhatsApp group for the duration of 4 weeks. The topics discussed were knowledge of albinism, sun protection practices, the use of sunscreen, and myths about albinism. They were all covered in 4 WhatsApp sessions held in 4 separate days. A web-based questionnaire was filled out before and after the intervention by the participants. Mann-Whitney U test was used to compare the pre- and postknowledge scores. Spearman correlation was used to correlate data.

RESULTS

The mean age of the study participants was 28.28 (SD 11.57) years. The number of participants was 140 in the preintervention period and 66 in the postintervention period. A statistically significant increase in overall knowledge (P=.01), knowledge of sunscreen (P=.01), and knowledge of sun protection (P<.01) was observed following the intervention. Before the intervention, a positive correlation was observed between age (r=0.17; P=.03) and education level (r=0.19; P=.02) with participants' overall knowledge. However, after the intervention, there was no significant correlation between knowledge and age or education level. A percentage increase of 5.23% was observed in the overall knowledge scores following the intervention.

CONCLUSIONS

WhatsApp is an effective tool for educating people with albinism and can act as an alternative to the conventional methods of health education. It shows promising outcomes irrespective of the health literacy level of people with albinism. This educational intervention can positively impact behavior change and translate to consistent sun protection practices. The limitations of this study include the possibility of social desirability bias and data security.

A Comparative Study between Onion Peel Extracts, Free and Complexed with β-Cyclodextrin, as a Natural UV Filter to Cosmetic Formulations

The growing concern regarding the adverse effects of synthetic UV filters found in sunscreens has spurred significant attention due to their potential harm to aquatic ecosystems and human health. To address this, the present study aimed to extract and microencapsulate sensitive bioactive compounds derived from by-product onion peel (OP) by molecular inclusion using β-cyclodextrin as the wall material. Identification and quantification of bioactive compounds within the extract were conducted through high-performance liquid chromatography (HPLC-DAD) analysis, revealing quercetin and resveratrol as the primary constituents. The photoprotection capacity, evaluated by the sun protection factor (SPF), revealed a protection factor comparable to the value for a synthetic UV filter. The produced microparticles presented high antioxidant capacity, significant photoprotection capacity, encapsulation efficiency of 91.8%, mean diameter of 31 μm, and polydispersity of 2.09. Furthermore, to comprehensively evaluate the performance of OP extract and its potential as a natural UV filter, five O/W emulsions were produced. Results demonstrated that microparticles displayed superior ability in maintaining SPF values over a five-week period. Photoprotection evaluation-skin reactivity tests revealed that both extract and microparticles absorb UV radiation in other regions of UV radiation, revealing their potential to be used as a natural UV filter to produce a sustainable and eco-friendly value-added sunscreen.

Sun protection use and habits in the LGBTQI+ community in Lebanon: A cross sectional study

BACKGROUND

Sun exposure is an extrinsic risk factor for skin aging, wrinkle formation, and the development of skin cancer, namely melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Sun protection measures have emerged as an important means of preventing these harmful effects. Studies have shown that sexual minority men have a greater prevalence of skin cancer than heterosexual men.

AIMS

There is limited research investigating the reasons behind this risk of skin cancer development. This is especially important because identifying preventable risk factors, like those pertaining to sun exposure behaviors, can be targeted in the fight against skin cancer and help establish screening tools and preventive interventions for the SGM community. This study focused on members of the SGM community and demonstrated their tendency not to use sun-protective measures, as well as their deficits in knowledge of skin cancer prevention.

MATERIALS AND METHODS

This study is a cross-sectional study that investigates sun protection practices and trends among adults in Lebanon's SGM community using a survey. It includes adults aged 18-80 that were recruited from the dermatology clinics at AUBMC as well as LGBTQ+ organizations Helm and SIDC.

RESULTS

A total of 129 participants took part in the study and completed the survey. Reasons for tanning varied among our participants: tanning to get a color (13.1%), tanning to get vitamin D (4.6%), tanning socially (6.9%), and tanning for mood elevation (0.8%). No significant association was found between sexual orientation and SPF use (p = 0.167). No significant association was found between sexual orientation and tanning frequency during summer (p-value: 0.231). Similarly, no significant association was noted between sexual orientation and tanning bed use (0.951). No significant association was noted between the type of job and SPF use (p = 0.601). Despite no significance between SPF use and the highest educational degree attained (p = 0.070), the tendency to use SPF increased with higher levels of education. Moreover, awareness of sun-induced skin cancer did not significantly affect SPF use (p = 0.067). However, a significant association was found between the information source for skin cancer and SPF use (p < 0.001) where participants receiving information from dermatologists displayed notably higher SPF use (72.2%), compared to those obtaining information from media (18.2%) or family and friends (5.3%).

DISCUSSION

Surveying the perception of the Lebanese SGM community towards sun damage and their adaptive practices to prevent it can help implement and gear a nation-wide campaign to spread proper awareness about this subject. Studying their behavioral tendencies for not using sunscreen can help overcome this contributing risk factor for skin cancers.

CONCLUSION

Future investigations have yet to identify confounding variables contributing to higher levels of skin cancers in this population.

Comparison between endocrine activity assessed using ToxCast/Tox21 database and human plasma concentration of sunscreen active ingredients/UV filters

Sunscreen products are composed of ultraviolet (UV) filters and formulated to reduce exposure to sunlight thereby lessening skin damage. Concerns have been raised regarding the toxicity and potential endocrine disrupting (ED) effects of UV filters. The ToxCast/Tox21 program, that is, CompTox, is a high-throughput in vitro screening database of chemicals that identify adverse outcome pathways, key events, and ED potential of chemicals. Using the ToxCast/Tox21 database, octisalate, homosalate, octocrylene, oxybenzone, octinoxate, and avobenzone, 6 commonly used organic UV filters, were found to have been evaluated. These UV filters showed low potency in these bioassays with most activity detected above the range of the cytotoxic burst. The pathways that were most affected were the cell cycle and the nuclear receptor pathways. Most activity was observed in liver and kidney-based bioassays. These organic filters and their metabolites showed relatively weak ED activity when tested in bioassays measuring estrogen receptor (ER), androgen receptor (AR), thyroid receptor, and steroidogenesis activity. Except for oxybenzone, all activity in the endocrine assays occurred at concentrations greater than the cytotoxic burst. Moreover, except for oxybenzone, plasma concentrations (Cmax) measured in humans were at least 100× lower than bioactive (AC50/ACC) concentrations that produced a response in ToxCast/Tox21 assays. These data are consistent with in vivo animal/human studies showing weak or negligible endocrine activity. In sum, when considered as part of a weight-of-evidence assessment and compared with measured plasma concentrations, the results show these organic UV filters have low intrinsic biological activity and risk of toxicity including endocrine disruption in humans.

Smartwatch Technology in Medicine: A Call for Future Dermatologic Research

Collapse

Prevalence, characteristics, and knowledge related to photosensitivity in patients with lupus erythematosus: the international PHOTOLUP study

OBJECTIVES

To assess the prevalence, characteristics and knowledge about photosensitivity and the use of photoprotective measures in an international cohort of cutaneous and systemic lupus erythematosus patients.

METHODS

We conducted an international, cross-sectional study based on a 46-question web-based survey including patients with medically confirmed LE conducted between November 2021 and April 2022.

RESULTS

600 patients with lupus erythematosus (94% female, median age: 41 years [IQR: 33-51]) from 50 countries were included. A history of photosensitivity was reported by 389/600 (64.8%) patients. Photosensitivity was associated with the presence of other cutaneous involvement (OR = 3.8; 95%CI 2.5-5.7; p < 0.001) and differed according to the area of habits and level of education (p < 0.001, for all). Photosensitivity was characterized by a wide range of clinical manifestations (both cutaneous and systemic symptoms in 56.1% and systemic symptoms only in 29.8% of patients). Fatigue was the most frequently reported systemic manifestation (82.3%). Overall, 559/600 (93%) patients were aware of the detrimental role of UV exposure in lupus erythematosus, but 160/480 (33.3%) were unaware of the importance of photoprotective measures, including 90/310 (29%) among those with photosensitivity.

CONCLUSION

A high rate of self-reported photosensitivity characterize lupus erythematosus patients. Photosensitivity frequently includes subjective features, which makes it difficult to evaluate in clinical practice. As fatigue is frequent in LE, further study is needed to clarify its causal link with UV exposure. About one-third of lupus erythematosus patients are unaware of the importance of photoprotective measures. This should be improved through more frequent and targeted awareness interventions.

An investigation of the effects of topical sunscreen protection products under natural weather conditions on intrinsic color stability in maxillofacial silicones

Aim

The relatively short lifespan of maxillofacial prostheses (ranging from 3-24 months) is mostly a result of colour instability of silicone elastomers caused by ultraviolet (UV) radiation, requiring frequent remakes. An improvement in colour preservation could result in fewer remakes, thus saving time and money for both clinician and patient. In the quest for a suitable colour protection method, sunscreen protection products were considered; the most recent study on this subject was carried out in 1994, albeit using a low protection factor. The aim of this research was to determine if there is value in using topical sun protection products on extraoral silicone prostheses to prevent colour degradation.

Settings and Design

This was an in vitro quantitative study.

Materials and Methods

Three commercially available sunscreen products were studied, Riemann P20, Boots Soltan, and Garnier Ambre Solaire all with a sun protection factor of 50. A total of 144 silicone elastomer samples were produced using a Caucasian (light) shade 1.2 (n = 72) and dark skin shade 3.2 (n = 72) from the Technovent Ltd. Reality Shade range. Each shade group (n = 72) was divided into three groups to be subjected to outdoor weathering (n = 24), indoor (n = 24), and dark storage (n = 24). Within each environmental group, samples were divided into groups of six samples (n = 6) to receive the three sunscreens plus a control group with no sunscreen. The CIEL* a* b* formula was used to obtain the color measurements.

Statistical Analysis Used

One way ANOVA test and Tukey's HSD test for multiple comparisons was used to analyse the data.

Results

The ΔE values had changed for all samples throughout the aging process.

Conclusion

Soltan showed promising results in protecting the dark-shaded samples in the outdoor environment only.

When should sunscreen be applied: The balance between health benefit and adverse consequences to humans and the environment

OBJECTIVE

To propose a strategy for using sunscreens that optimizes the balance between skin health and adverse effects to humans and the environment.

METHODS

A model was developed to explore the relationship between sunscreen usage and personal sun exposure throughout the year in populations resident at different latitudes.

RESULTS

There is little biological justification in terms of skin health for applying sunscreen over the 4-6 winter months at latitudes of 45° N and higher, whereas year-round sunscreen is advised at latitudes of 30° N and lower. Avoiding sunscreen application at times when it is biologically unnecessary results in an annual reduction in sunscreen use of 25%. Furthermore, using products containing UV filters over the winter months at more northerly latitudes could lead to a higher number of people with vitamin D deficiency. The single largest use of sunscreen is on a sun-seeking holiday and encouragement to make more use of clothing and shade would appreciably reduce the sunscreen burden to the environment.

CONCLUSION

We need to use sunscreens wisely so that we gain the health benefit from their use while at the same time limiting possible harm to ourselves and the environment.

A Cost-Based Analysis of Anti-aging Products Across Four Major United States Retailers

Background In the field of aesthetic dermatology, there is currently very little data on affordability and cost analysis regarding cosmeceuticals as more demand from patients showing interest in cosmeceutical products to reduce and prevent aging continues to grow. Photoaging, a form of extrinsic aging from sun exposure, can be ameliorated by applying sunscreen and retinol products. Topical ascorbic acid and niacinamide have been shown to target the oxidative stress process that contributes to photoaging. These four products have been identified as the cosmeceutical ingredients with the most evidence-based data on photoaging prevention and treatment. Objective Given the demand for effective skin care, the paucity of data on cost differentiation, and the availability of cosmeceutical products, we analyzed the unit cost of four anti-aging products from major online and physical retailers in the United States. Such a cost comparison may facilitate more economically appropriate recommendations on skin care to consumers. Methods and materials We analyzed sunscreen, topical vitamin C (ascorbic acid), topical vitamin B3 (niacinamide), and topical vitamin A (retinol) products sold by four major United States retailers: Walmart, Ulta, Walgreens, and Amazon. The average cost in dollars per ounce (dollar/oz) was calculated for each product category at each retailer. Statistical analyses were done to determine statistical significance for each product category between retailers as well as between each category of product. Results Between the four retailers, Walmart offered the lowest cost per ounce for every product. In contrast, Amazon offered the highest cost per ounce for every product except for sunscreen. We also found that sunscreen products are less expensive per ounce as compared to retinol, ascorbic acid, and niacinamide products. Conclusion Dermatologists should be knowledgeable of product costs when providing patients with anti-aging product recommendations. Our study provides data on the financial cost by retail location of evidence-based anti-aging cosmeceuticals to better guide physicians in patient consulting and economical resource sharing.

The adverse consequences of not using sunscreens

The adverse effects of solar ultraviolet radiation (UVR) on normal skin are well established, especially in those with poorly melanized skin. Clinically, these effects may be classified as acute, such as erythema or chronic such as keratinocyte and melanocyte skin cancers. Apart from skin type genetics, clinical responses to solar UVR are dependent on geophysical (e.g., solar intensity) and behavioural factors. The latter are especially important because they may result in 'solar overload' with unwanted clinical consequences and ever greater burdens to healthcare systems. Correctly used, sunscreens can mitigate the acute and chronic effects of solar UVR exposure. Laboratory studies also show that sunscreens can inhibit the initial molecular and cellular events that are responsible for clinical outcomes. Despite public health campaigns, global trends continue to show increasing incidence of all types of skin cancer. Large-scale epidemiological studies have shown the benefits of sunscreen use in preventing skin cancer, though it is likely that sunscreen use has not been optimal in such studies. It is evident that without substantial changes in sun-seeking behaviour, sunscreen use is a very important part of the defence against the acute and chronic effects of solar exposure. Ideally, sunscreens should be able to provide the level of protection that reduces the risk of skin cancer in susceptible skin types to that observed in heavily melanized skin.

Does dinocyst wall composition really reflect trophic affinity? New evidence from ATR micro-FTIR spectroscopy measurements

Attenuated total reflection (ATR) microscope Fourier transform infrared (micro-FTIR) spectroscopy was used to investigate the dinosporin composition in the walls of modern, organic-walled dinoflagellate resting cysts (dinocysts). Variable cyst wall compositions were observed, which led to the erection of four spectrochemical groups, some with striking similarities to other resistant biomacromolecules such as sporopollenin and algaenan. Furthermore, possible proxies derivable from the spectrochemical composition of modern and fossil dinocysts were discussed. The color of the dinocyst walls was reflected in the spectral data. When comparing that color with a standard and the results of a series of bleaching experiments with oxidative agents, eumelanin was assigned as a likely pigment contributing to the observed color. Following this assignment, the role of eumelanin as an ultraviolet sunscreen in colored dinocysts was hypothesized, and its implications on the autofluorescence and morphological preservation of dinocysts were further discussed. Unlike what had previously been assumed, it was shown that micro-FTIR data from dinocysts cannot be used to unambiguously infer trophic affinities of their associated cells. Finally, using methods with high spatial resolutions (synchrotron transmission micro-FTIR and optical photothermal infrared spectroscopy), it was shown that dinocyst wall layers are chemically homogenous at the probed scales. This study fills a large knowledge gap in our understanding of the chemical nature of dinocyst walls and has nuanced certain assumptions and interpretations made in the past.

Sunscreens - another endangered species?

Skin cancer continues to increase in incidence year-on-year and represents the most common form of cancer across the globe. Every human undergoes premature ageing, particularly on the face, neck and hands. Both phenomena are driven primarily by chronic, daily exposure to solar ultraviolet radiation (UVR). While sunscreen products play a primary role in the prevention of UVR skin damage, the active ingredients, i.e., UVR filters, are facing unprecedented challenges in the coming 10 years and their future is by no means certain. This article, therefore, reviews afresh the facts around photoprotection and the role of sunscreen products in the prevention of acute (sunburn) and chronic (cancer, photoageing) skin damage and compares/contrasts these with various emerging questions and opinions around UVR filter technology. We present a passionate defence of this remarkable technology, but also attempt to imagine a world without it.

Cosmetic UV filters in the environment-state of the art in EU regulations, science and possible knowledge gaps

OBJECTIVE

The aim of this work was to review the principals of environmental hazard and risk assessment (ERA) of cosmetic UV filters registered under EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals). Furthermore, effects as obtained from non-standardized testing methods and organisms from scientific literature were compared against the predicted no effect concentrations (PNECs) as derived based on standardized test methods for the various environmental compartments under REACH.

METHODS

The REACH dossiers at the ECHA webpage were screened for available information related to basic physico-chemical data (i.e. water solubility, octanol-water partitioning coefficient), PNECs and associated data (data basis, assessment factors (AFs)). Scientific literature was screened for available ecotoxicity data and the adverse effect levels were compared against the derived PNECs under REACH. Current approaches for environmental risk assessments of UV filters were evaluated for its applicability for a direct release scenario.

RESULTS

Under REACH, PNECs were derived for all hazardous UV filters. Although, PNECs were often derived for various environmental compartments (i.e. freshwater, marine water, sediment, soil), results from literature focused on aquatic data. Effects as observed within scientific literature matches in principle with the hazardous profile of the UV filters. Effects levels both on the acute and the chronic toxicity as retrieved from the non-standardized test organisms (literature) were above the derived PNECs under REACH. Currently, ERAs performed for cosmetic UV filters under REACH are solely tonnage driven and thus do not fully capture the use in sunscreens and associated leisure activities.

CONCLUSION

Existing EU REACH regulation is considered as sufficient to evaluate the environmental safety of UV filters used in sunscreens. To cover the direct release of UV filters due to various leisure activities into the aquatic freshwater and marine environment, an additional application-based ERA is considered necessary.

Repurposing consumer sunscreen habits and practices survey data to guide the development of UV filter environmental exposure models and risk assessments

OBJECTIVE

A key factor that is deficient in most environmental emissions assessments for UV filters is a keen understanding of consumer habits and practices that can inform realistic exposure assessments. This study utilized a large volunteer survey (>11 000 persons) that captured many factors that affect consumer-based loadings to aquatic environments. The purpose of this study was to utilize this large survey to identify factors that affect the amount of sunscreen products used by consumers.

METHODS

Correlations among more than 20 variables were used to provide an understanding of the overall dataset and identify factors that may be related to the amount of sunscreen product applied to the body (i.e., application thickness). Forward multiple linear regressions were used to identify the relative importance of each of these factors alone and in combination with others in predicting the amount of applied sunscreen.

RESULTS

The proportion of body surface area (BSA) covered by sunscreen was the primary factor related to application thickness, followed by body surface area of the survey participant, seasonal usage, Fitzpatrick skin type and the sun protection factor, respectively. Each of the five regression models examined was statistically highly significant.

CONCLUSIONS

Comparisons to recommendations from the National Academies of Science, Engineering and Medicine parameters illustrated sufficient differences so as to encourage the development of future consumer habits and practice surveys that include factors beyond the scope of this study (e.g., activities, time of day, year, location, etc.) that can lead to improved exposure and risk assessments.

Sunscreen Label Marketing Towards Pediatric Populations: Guidance for Navigating Sunscreen Choice

INTRODUCTION

 Sunscreen marketing to specific demographics is largely unregulated. Marketing specifically targeting pediatric populations has the potential to drive consumer behavior. The American Academy of Pediatrics (AAP) and American Academy of Dermatology (AAD) provide recommendations for sunscreen use in children over the age of six months. This study sought to determine if sunscreen products marketed toward pediatric populations align with healthcare guidelines.

MATERIALS AND METHODS

Sunscreens available in major retail outlets in the Philadelphia area were cataloged and reviewed for marketing targeting specific demographics such as "baby", "babies", "children", "kids", "sports", and "active". The products were reviewed for sun protection factor (SPF), broad-spectrum ultraviolet (UV) protection, water resistance, active UV filters, and application method.  Results: Of 410 sunscreens cataloged, 27 were marketed towards "baby" or "babies", 44 towards "children" or "kids", and 71 towards "sports" or "active". All of the sunscreen products reviewed targeting the pediatric population offered water resistance for up to 80 minutes and broad-spectrum UV coverage. Sunscreens targeting "baby" or "babies" aligned most closely with AAP guidelines for sunscreen use in pediatric populations, with 92.6% offering an SPF between 15 to 50 and no products including oxybenzone as a UV filter. However, sunscreens targeting "children", "kids", "sports", and "active" bore a close resemblance to the overall sunscreen profile for all demographics but with a higher percentage of products containing oxybenzone. Oxybenzone was found in 11.4% of "children" and "kids" products and 16.9% of "sports" and "active" sunscreen products, compared to 7.6% of all sunscreen products available, and was also found in most sunscreen products with an SPF of 70 or higher.

CONCLUSION

 Sunscreen products marketed towards "baby" and "babies" tend to align closely with guidelines for sunscreen use in the pediatric population for children over six months of age; however, those with brand marketing towards "children", "kids", "sports", and "active" do not. Limiting recommendations for a sunscreen product with an SPF of 30 to 50 targeting this demographic, however, sufficiently meets guidelines set forth by the AAP and AAD.

Cutaneous interaction with visible light: What do we know?

Visible light has been used therapeutically in dermatology for years for a variety of cosmetic and medical indications, including skin rejuvenation and the treatment of inflammatory and neoplastic conditions, among others. Until recently, visible light was thought to be relatively inert compared to its spectral neighbors, ultraviolet and infrared radiation. However, recent literature has described the ability of visible light to cause erythema in light skin and pigmentary changes in individuals with darker skin types. Concern surrounding its potentially damaging cutaneous effects has been raised in both the medical community and social media outlets. In this article, we provide an evidenced-based review describing what is currently known about visible light, focusing on its role in dermatologic diseases including disorders of hyperpigmentation such as melasma and postinflammatory hyperpigmentation.

Caffeine in Skincare: Its Role in Skin Cancer, Sun Protection, and Cosmetics

Caffeine is ubiquitous in our society-not only in the drinks consumed but also increasingly in dermatologic topicals. Given that coffee and caffeine are increasingly used for the production of many dermatologic anti-cancer topicals, sunscreens, and cosmetics, it is of imperative importance to review the basic science and clinical evidence for such claims. In this concise review, we outline the current evidence.

Outdoor clinical testing with reference sunscreens to determine differences in skin response between populations of different ethnicity: A combined data analysis from 128 subjects

BACKGROUND

Two previously published clinical studies by our group assessed erythema and pigmentation responses in outdoor conditions with three reference sunscreens, comparing their effectiveness under the full spectrum of natural sunlight. These studies followed an almost identical protocol but were conducted in two different locations and in two ethnic groups: broadly, Chinese (Singapore) and White European (Mauritius). We analysed the data from these two study populations to compare differences in skin response according to ethnicity.

METHODS

The analysis included 128 subjects (53 were Chinese from Singapore and 75 were White European from Mauritius and Singapore). Products used were the reference sunscreens P3 (sun protection factor [SPF] 15), P5 (SPF 30) and P8 (SPF 50+) from ISO norm 24444:2019. Participants were exposed to outdoor sunlight for 2-3 h, depending on baseline ITA. Endpoints were erythema at 24 h: clinical score and colorimetry (Δa*) and pigmentation at 1 week based on colorimetry (ΔL* and ΔITA).

RESULTS

Among those with baseline ITA > 41, there were differences in erythemal response between the Chinese and White European groups, the White European group being more erythematous and also having a higher rate of photoprotection failure particularly at SPFs 15 and 30.

CONCLUSION

Differences in skin response to sun influenced by ethnicity should be taken into account when making recommendations on sun safety.

Is sunscreen alone effective at preventing sunburn on a high-solar beach vacation: A modeling study?

Beach holidays in areas of strong sunlight are popular and sunscreen is often the primary means of photoprotection favored by many people. The object of this study was to estimate how effective sunscreen is in preventing sunburn under high ultraviolet (UV) levels. We used a computational model to determine how the quantity, frequency, substantivity, and labeled SPF of applied sunscreens impact on the predicted erythemal response in unacclimatized skin over the course of a 7-day holiday in a high-solar environment. Our results indicated that sunscreen on its own may be insufficient to prevent sunburn in white skin on a sun-seeking holiday that combines prolonged exposure with high UV levels. Nevertheless, sunscreens have a valuable role to play on a beach holiday especially if an SPF30 or higher is chosen, the product is applied liberally and uniformly, application is started early into the sun exposure period and repeated at 2-hourly intervals throughout the day, and the product binds well to the skin. The main limitation of our investigation is that it is not an observational study but rather a computational model and while all models are wrong, some, including this one, are useful.

Characteristic Photoprotective Molecules from the Sphagnum World: A Solution-Phase Ultrafast Study of Sphagnic Acid

A natural UV-absorbing chromophore extracted from sphagnum mosses, sphagnic acid, is proposed as a new natural support to chemical UV filters for use in cosmetic applications. Sphagnic acid is structurally related to the cinnamate family of molecules, known for their strong UV absorption, efficient non-radiative decay, and antioxidant properties. In this study, transient electronic absorption spectroscopy is used, in conjunction with steady-state techniques, to model the photodynamics following photoexcitation of sphagnic acid in different solvent systems. Sphagnic acid was found in each system to relax with lifetimes of ~200 fs and ~1.5 ps before generating a cis-isomer photoproduct. This study helps to elucidate the photoprotective mechanism of a new potential natural support to sunscreens, from a unique plant source.

Human-Hair-Derived Natural Particles as Multifunctional Sunscreen for Effective UV Protection

Excessive ultraviolet (UV) radiation can lead to a series of skin problems. Although commercial sunscreens can protect skin from UV-induced damage to an extent, the side effects caused by such products are still worrisome. Here, inspired by the natural photoprotection effect of human hair, we extracted the multifunctional particles from human hair as sunscreens for UV protection. Both in vitro and in vivo results indicate that hair-derived particles (HDPs) could effectively protect skin from UV radiation. Besides, HDPs retain the antioxidant capability of melanin in hair, which avoids UV-induced oxidative damage. In addition, the unique shape of HDPs can prevent them from penetrating into the skin, thus avoiding potential toxicity. Moreover, owing to their mesoporous structure, the particles can also be used as drug carriers. With the loading of octocrylene, the particles are more effective in blocking UV radiation. This study provides an ingenious tactic for the design and development of sunscreens from a natural substance.

Gadusol is a maternally provided sunscreen that protects fish embryos from DNA damage

Exposure to ultraviolet radiation (UVR) is harmful to living cells, leading organisms to evolve protective mechanisms against UVR-induced cellular damage and stress.1,2 UVR, particularly UVB (280-320 nm), can damage proteins and DNA, leading to errors during DNA repair and replication. Excessive UVR can induce cellular death. Aquatic organisms face risk of UV exposure as biologically harmful levels of UVB can penetrate >10 m in clear water.3 While melanin is the only known sunscreen in vertebrates, it often emerges late in embryonic development, rendering embryos of many species vulnerable during the earlier stages. Algae and microbes produce a class of sunscreening compounds known as mycosporine-like amino acids (MAAs).4 Fish eggs contain a similar compound called gadusol, whose role as a sunscreen has yet to be tested despite its discovery over 40 years ago.5 The recent finding that many vertebrate genomes contain a biosynthetic pathway for gadusol suggests that many fish may produce and use this molecule as a sunscreen.6 We generated a gadusol-deficient mutant zebrafish to investigate the role of gadusol in protecting fish embryos and larvae from UVR. Our results demonstrate that maternally provided gadusol is the primary sunscreen in embryonic and larval development, while melanin provides modest secondary protection. The gadusol biosynthetic pathway is retained in the vast majority of teleost genomes but is repeatedly lost in species whose young are no longer exposed to UVR. Our data demonstrate that gadusol is a maternally provided sunscreen that is critical for early-life survival in the most species-rich branch of the vertebrate phylogeny.

In vivo evaluation of sunscreen application by multispectral imaging: A new tool for educating sunscreen users

BACKGROUND

The sun protection factor (SPF) of sunscreens is evaluated using standardized protocols based on the application of 2 mg/cm2 of product. However, the amount of product applied by sunscreen users in real life is likely to be much lower.

OBJECTIVES

To evaluate a new multispectral imaging approach for determining the actual quantity of sunscreen applied by users and to assess the benefits of an application guide for the use of an SPF 50+ sunscreen.

MATERIALS AND METHODS

Analyses of the reflectance spectra obtained from multispectral images were used to determine the actual dose of sunscreen that 26 healthy volunteers applied to their face following three application modalities: a single application, reapplication after 30 min, and application according to an instruction guide.

RESULTS

Without the application guide, volunteers applied an average of 1.04 mg/cm2 of sunscreen during the single application and 1.23 mg/cm2 during the repeated application. With the application guide, the amount of sunscreen applied was 1.45 mg/cm2 : around 40% higher than during the single application. Spreading of the sunscreen was also less uniform with the unguided single application than with the other application modalities.

CONCLUSIONS

This study showed that the multispectral imaging approach can be used to measure the amount of sunscreen applied in vivo. Our findings confirmed that the standard dose used for SPF measurements and other sunscreen tests is far higher than that applied by users in practice. Providing users with precise guidelines could increase the amount of sunscreen applied, resulting in more adequate photoprotection.