Dermal absorption of cyclic and linear siloxanes: a review.

Cyclic and linear siloxanes are compounds synthesized from silicon consisting of alternating atoms of silicone and oxygen [Si-O] units with organic side chains. The most common cyclic siloxanes are octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6), while the most common linear siloxanes are high molecular weight polydimethylsiloxanes (PDMS) and low molecular weight volatile linear siloxanes known as hexamethyldisiloxane (L2), octamethyltrisiloxane (L3), decamethyltetrasiloxane (L4), dodecamethylpentasiloxane (L5). These compounds (1) exhibit low dermal toxicity, (2) are generally inert and non-reactive, and (3) are compatible with a wide range of chemicals offering beneficial chemical properties which include the following: wash-off or transfer resistance from the skin, sun protection factor (SPF) enhancement, emolliency in cleaning products). Because of these properties, these compounds are incorporated into multiple consumer products for use on the skin, such as cosmetics and health-care products, with over 300,000 tons annually sold into the personal care and consumer products sector. Because of their widespread use in consumer products and potential for human dermal exposure, a comprehensive understanding of the dermal absorption and overall fate of siloxanes following dermal exposure is important. This review summarizes available data associated with the dermal absorption/penetration as well as fate of the most commonly used siloxane substances.

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.

Sunscreens Part 2: Regulation and Safety.

The second part of this CME article discusses sunscreen regulation and safety considerations for humans and the environment. First, we provide an overview of the history of the United States Food and Drug Administration's regulation of sunscreen. Recent Food and Drug Administration studies clearly demonstrate that organic ultraviolet filters are systemically absorbed during routine sunscreen use, but to date there is no evidence of associated negative health effects. We also review the current evidence of sunscreen's association with vitamin D levels and frontal fibrosing alopecia, and recent concerns regarding benzene contamination. Finally, we review the possible environmental effects of ultraviolet filters, particularly coral bleaching. While climate change has been shown to be the primary driver of coral bleaching, laboratory-based studies suggest that organic ultraviolet filters represent an additional contributing factor, which led several localities to ban certain organic filters.

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.

Toxicokinetics of homosalate in humans after dermal application: applicability of oral-route data for exposure assessment by human biomonitoring.

Homosalate (HMS) is a UV filter used in sunscreens and personal care products as a mixture of cis- and trans-isomers. Systemic absorption after sunscreen use has been demonstrated in humans, and concerns have been raised about possible endocrine activity of HMS, making a general population exposure assessment desirable. In a previous study, it was shown that the oral bioavailability of cis-HMS (cHMS) is lower than that of trans-HMS (tHMS) by a factor of 10, calling for a separate evaluation of both isomers in exposure and risk assessment. The aim of the current study is the investigation of HMS toxicokinetics after dermal exposure. Four volunteers applied a commercial sunscreen containing 10% HMS to their whole body under regular-use conditions (18-40 mg HMS (kg bw)-1). Parent HMS isomers and hydroxylated and carboxylic acid metabolites were quantified using authentic standards and isotope dilution analysis. Further metabolites were investigated semi-quantitatively. Elimination was delayed and slower compared to the oral route, and terminal elimination half-times were around 24 h. After dermal exposure, the bioavailability of cHMS was a factor of 2 lower than that of tHMS. However, metabolite ratios in relation to the respective parent isomer were very similar to the oral route, supporting the applicability of the oral-route urinary excretion fractions for dermal-route exposure assessments. Exemplary calculations of intake doses showed margins of safety between 11 and 92 (depending on the approach) after single whole-body sunscreen application. Human biomonitoring can reliably quantify oral and dermal HMS exposures and support the monitoring of exposure reduction measures.

Subjective and objective assessment of color match of universal tinted sunscreens in Fitzpatrick skin phototypes I-VI.

BACKGROUND: Tinted sunscreens not only shield against UV rays but also provide protection against visible light, as opposed to traditional sunscreens. Universal tinted sunscreens are marketed to complement all skin tones. OBJECTIVE: To assess color match and subject satisfaction for 7 universal tinted sunscreens across various price ranges in all Fitzpatrick skin phototypes (SPT). METHODS: Products A-G were applied at concentrations of 1 and 2 mg/cm2 on the dorsal arms of 30 subjects spanning SPT I-VI. Photography, colorimetry, and subject and investigator surveys were utilized to determine color match. RESULTS: Using colorimetry analysis at the recommended 2 mg/cm2 concentration, two of seven products were identified as suitable matches for SPT I-II, while six out of seven were determined to be a good match for SPT III-IV. However, only one product was found to be a good match for SPT V-VI at the recommended concentration according to colorimetry results. CONCLUSION: Universal tinted sunscreens do not provide an adequate color match for all skin phototypes, especially for individuals with very fair or very dark skin tones.

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, Kolobrzeg, 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.

Ecotoxicological assessment of UV filters benzophenone-3 and TiO2 nanoparticles, isolated and in a mixture, in developing zebrafish (Danio rerio).

The increasing use of UV filters, such as benzophenone-3 (BP-3) and titanium dioxide nanoparticles (TiO2 NPs), has raised concerns regarding their ecotoxicological effects on the aquatic environment. The aim of the present study was to examine the embryo-larval toxicity attributed to BP-3 or TiO2 NPs, either alone or in a mixture, utilizing zebrafish (Danio rerio) as a model after exposure to environmentally relevant concentrations of these compounds. Zebrafish embryos were exposed to BP-3 (10, 100, or 1000 ng/L) or TiO2 NPs (1000 ng/L) alone or in a mixture (BP-3 10, 100, or 1000 ng/L plus 1000 ng/L of TiO2 NPs) under static conditions for 144 hr. After exposure, BP-3 levels were determined by high-performance liquid chromatography (HPLC). BP-3 levels increased in the presence of TiO2 NPs, indicating that the BP-3 degradation decreased in the presence of the NPs. In addition, in the presence of zebrafish, BP-3 levels in water decreased, indicating that zebrafish embryos and larvae might absorb BP-3. Data demonstrated that, in general, environmentally relevant concentrations of BP-3 and TiO2 NPs, either alone or in a mixture, did not significantly induce changes in heart and spontaneous contractions frequencies, levels of reactive oxygen species (ROS), morphological and morphometric parameters as well as mortality rates during 144 hr exposure. However, the groups exposed to TiO2 NPs alone and in a mixture with BP-3 at 10 ng/L exhibited an earlier significant hatching rate than the controls. Altogether, the data indicates that a potential ecotoxicological impact on the aquatic environment exists.

Sunscreens prescribed to patients with skin of color and/or with melasma: A survey of 221 dermatologists and dermatology residents in Spain.

BACKGROUND: Dark-skinned individuals (DSI) present high rates of melasma and post-inflammatory hyperpigmentation. The use of sunscreens with mineral filters is essential for prevention and treatment. Our objective was to determine the preferences of dermatologists and dermatology residents in the prescription of sunscreens for DSI. METHODS: An anonymous survey of attendees at an online photoprotection event held on March 31, 2022, in Spain. RESULTS: The survey was answered by 66.6% (221/332) of the attendees: 159 dermatologists (71.9%) and 62 dermatology residents (28.1%). Respondents reported recommending the use of sunscreen to a median of 80% of DSI [interquartile range (IQR), 50-90]. Physicians reported prescribing tinted sunscreens to a median percentage of 60% (IQR, 25-90) of DSI with acne; and to a median percentage of 90% (IQR, 58-99) of DSI with melasma. The most prescribed photoprotectors to DSI with melasma were organic broad-spectrum sunscreens with antioxidants: 102/220 (46.4%) and mineral broad-spectrum sunscreens (with iron oxides): 45/220 (20.4%). In DSI with melasma or other pigmentary disorders, the most preferred features of sunscreens were as follows: sun protection factor ≥ 30: 217/221 (98.2%), UVA protection: 214/221 (96.8%), color for camouflage: 150/220 (68.2%) and mineral filters such as titanium dioxide and zinc oxide: 151/220 (68.6%) or iron oxides: 131/220 (59.5%). LIMITATIONS: Online survey, potential inclusion bias. CONCLUSIONS: Respondents reported to prescribe sunscreens to the majority of DSI, and tinted sunscreens for the majority of DSI with pigmentary disorders. However, the most frequently recommended sunscreens for DSI were organic broad-spectrum sunscreens with antioxidants.

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.

Understanding the causes of skincare product pilling.

BACKGROUND: Skincare and makeup "pilling" is an unsightly and undesirable phenomenon whereby skincare such as moisturizers or foundation ball up to form flakes on the skin. To date, the causes of skincare product pilling have not been studied. This study aimed to examine the relationship between skin physiology and pilling potential of sunscreen and foundation (the two products most reported by consumers to cause pilling). This study also examined the effects of product application methods on pilling. MATERIALS AND METHODS: 528 female volunteers from Guangzhou, China, aged between 20 and 49 years, underwent various clinical skin assessments, followed by three steps of product layering. Pilling was assessed after each product application step. RESULTS: 217 volunteers (41%) experienced pilling. The majority of pilling (n = 655 events) occurred following sunscreen application, while only a few pilling events (n = 35) occurred with foundation. Foundation improved pilling caused by sunscreen in 98.9% of cases. Volunteers experiencing pilling with both sunscreen and foundation had significantly lower facial skin hydration and oiliness, higher pH, and smoother skin texture (P < 0.05). Two application methods, rubbing of products in circular and linear motions, yielded the highest numbers of pilling events. CONCLUSION: This study has provided the first insights into the causes of pilling. Sunscreen is a promoter of pilling, while foundation may resolve sunscreen-induced pilling in many cases. Skin physiology, particularly drier, smoother skin with higher pH, and product application methods are likely contributing factors to this undesirable phenomenon.

Digital Interventions to Modify Skin Cancer Risk Behaviors in a National Sample of Young Adults: Randomized Controlled Trial.

BACKGROUND: Young adults engage in behaviors that place them at risk for skin cancer. Dissemination of digital health promotion interventions via social media is a potentially promising strategy to modify skin cancer risk behaviors by increasing UV radiation (UVR) protection and skin cancer examinations. OBJECTIVE: This study aimed to compare 3 digital interventions designed to modify UVR exposure, sun protection, and skin cancer detection behaviors among young adults at moderate to high risk of skin cancer. METHODS: This study was a hybrid type II effectiveness-implementation randomized controlled trial of 2 active interventions, a digital skin cancer risk reduction intervention (UV4.me [basic]) compared with an enhanced version (UV4.me2 [enhanced]), and an electronic pamphlet (e-pamphlet). Intervention effects were assessed over the course of a year among 1369 US young adults recruited primarily via Facebook and Instagram. Enhancements to encourage intervention engagement and behavior change included more comprehensive goal-setting activities, ongoing proactive messaging related to previously established mediators (eg, self-efficacy) of UVR exposure and protection, embedded incentives for module completion, and ongoing news and video updates. Primary outcome effects assessed via linear regression were UVR exposure and sun protection and protection habits. Secondary outcome effects assessed via logistic regression were skin self-exams, physician skin exams, sunscreen use, indoor tanning, and sunburn. RESULTS: The active interventions increased sun protection (basic: P=.02; enhanced: P<.001) and habitual sun protection (basic: P=.04; enhanced P=.01) compared with the e-pamphlet. The enhanced intervention increased sun protection more than the basic one. Each active intervention increased sunscreen use at the 3-month follow-up (basic: P=.03; enhanced: P=.01) and skin self-exam at 1 year (basic: P=.04; enhanced: P=.004), compared with the e-pamphlet. Other intervention effects and differences between the Basic and Enhanced Intervention effects were nonsignificant. CONCLUSIONS: The active interventions were effective in improving several skin cancer risk and skin cancer prevention behaviors. Compared with the basic intervention, the enhanced intervention added to the improvement in sun protection but not other behaviors. Future analyses will explore intervention engagement (eg, proportion of content reviewed). TRIAL REGISTRATION: ClinicalTrials.gov NCT03313492; http://clinicaltrials.gov/ct2/show/NCT03313492.

Microencapsulation of sunscreen reduces toxicity of its components to A. salina: Biochemical, behavioral and morphological studies.

Sunscreens contain several substances that cause damage to species where they are disposed. New formulations have been created to prevent such marine environmental damages. One promising formulation is the microencapsulated sunscreen. The objective of this study was to evaluate the possible safety to marine environment of one microencapsulated sunscreen formulation. The animal model Artemia salina (cists and nauplii) was tested with two sunscreen formulations (microencapsulated and non-microencapsulated) and toxicological, behavioral, morphological parameters as well as biochemical assays (lipoperoxidation and carbonylation tests) were analyzed. Results showed that microencapsulated sunscreen impeded some toxic effects caused by the release of the substances within the microcapsule in the highest concentration, reestablishing the mortality and hatching rates to control levels, while removing the sunscreen microcapsule by adding 1 % DMSO reduced the cyst hatching rate, increasing the nauplii mortality rate and decreased locomotor activity in higher concentrations. Finally, nauplii with 24 hours of life and exposed to sunscreen without the microcapsule showed an increase in mitochondrial activity (assessed at 48 hours after exposure) and presented malformations when exposed to the highest concentration non-microencapsulated concentration (assessed by SEM at 72 hours after exposure), when compared to the control group. These results together allow us to conclude that the microencapsulation process of a sunscreen helps protecting A. salina from the harmful effects of higher concentrations of said sunscreens. However, long-term studies must be carried out as it is not known how long a microencapsulated sunscreen can remain in the environment without causing harmful effects to the marine ecosystem and becoming an ecologically relevant pollutant.

Behaviorally segmented audiences for managing sunscreen chemical pollution risk in protected coastal natural resource areas.

This audience segmentation of visitors at coastal parks in Hawaii and North Carolina addresses an emergent natural resource management concern and risk to aquatic ecosystems: sunscreen chemical pollution. Four audiences were identified that correspond to different behavioral profiles: sunscreen protection tourists, multimodal sun protection tourists, in-state frequent park visitors, and frequent beachgoers who skip sunscreen. The second-largest audience, sunscreen protection tourists, represents 29% of visitors at Cape Lookout National Seashore and 25% at Kaloko-Honokohau National Historical Park. This group ranks of most concern for chemical pollution because they use sunscreen, but not typically mineral formulations or other methods such as protective clothing, and they have lower levels of sunscreen chemical issue awareness. The identification of similar audience segments across regions with differing cultural characteristics and sunscreen regulation status suggests the robustness of the model and its indicator variables, with implications for both environmental protection and public health. Further, coastal visitors' interest in enacting pro-environmental sun protection behaviors during their next park or beach visit indicates the potential for natural resource managers to holistically address risks in both domains through targeted interventions with audiences of most concern.

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.

Optimization of an Ultrasound-Assisted Extraction Technique and the Effectiveness of the Sunscreen Components Isolated from Bletilla striata.

Bletilla striata is the dried tuber of B. striata (Thund.) Reichb.f., which has antibacterial, anti-inflammatory, anti-tumor, antioxidant and wound healing effects. Traditionally, it has been used for hemostasis therapy, as well as to treat sores, swelling and chapped skin. In this study, we used the ultraviolet (UV) absorbance rate of B. striata extracts as the index, and the extraction was varied with respect to the solid-liquid ratio, ethanol concentration, ultrasonic time and temperature in order to optimize the extraction process for its sunscreen components. The main compounds in the sunscreen ingredients of Baiji (B. striata) were analyzed using ultra-high-performance liquid chromatography combined with quadrupole time-of-flight tandem mass spectrometry. The sunscreen properties were subsequently evaluated in vitro using the 3M tape method. The results show that the optimal extraction conditions for the sunscreen components of B. striata were a solid-liquid ratio of 1:40 (g/mL), an ethanol concentration of 50%, an ultrasonic time of 50 min and a temperature of 60 °C. A power of 100 W and an ultrasonic frequency of 40 Hz were used throughout the experiments. Under these optimized conditions, the UV absorption rate of the isolated sunscreen components in the UVB region reached 84.38%, and the RSD was 0.11%. Eighteen compounds were identified, including eleven 2-isobutyl malic acid glucose oxybenzyl esters, four phenanthrenes, two bibenzyl and one α-isobutylmalic acid. An evaluation of the sunscreen properties showed that the average UVB absorption values for the sunscreen samples from different batches of B. striata ranged from 0.727 to 1.201. The sunscreen ingredients of the extracts from B. striata had a good UV absorption capacity in the UVB area, and they were effective in their sunscreen effects under medium-intensity sunlight. Therefore, this study will be an experimental reference for the extraction of sunscreen ingredients from the B. striata plant, and it provides evidence for the future development of B. striata as a candidate cosmetic raw material with UVB protection properties.

Cosmetic Products with Potential Photoprotective Effects Based on Natural Compounds Extracted from Waste of the Winemaking Industry.

Grape marc is a by-product resulting from the winemaking industry that still contains beneficial compounds that can be valorized. Thus, we report here the possibility of using polyphenolic extracts of grape marc origin to obtain sun protection creams. The extractions were performed in ethanol and acetone solutions using pomace from different grape varieties (Merlot, Bläufrankisch, Feteasca Neagra, Isabella) as a raw material. The obtained extracts were analyzed in order to determine the total phenolic content, the antioxidant activity, and the sun protection factor (SPF) via Mansur spectrophotometric assay. The best results were achieved using 70% ethanol in water as a solvent. The extracts with the highest potential photoprotective effects are from the Merlot variety (SPFspectrophotometric = 7.83 ± 0.76). The sunscreens were prepared using the 70% ethanolic extract of the Merlot variety evaporated to dryness, redissolved in either distilled water or ethanol. The SPF estimated in vitro via the COLIPA method showed values of 14.07 ± 1.50 and 11.46 ± 1.32 for the aqueous and ethanolic extracts, respectively, when working with a cream to polyphenolic extract a ratio of 1/1 (w/w). At the same time, the use of aqueous polyphenolic extracts ensures the better stability of creams compared with the ethanolic ones.

Photochemical and Oxidative Degradation of Chamazulene Contained in Artemisia, Matricaria and Achillea Essential Oils and Setup of Protection Strategies.

Chamazulene (CA) is an intensely blue molecule with a wealth of biological properties. In cosmetics, chamazulene is exploited as a natural coloring and soothing agent. CA is unstable and tends to spontaneously degrade, accelerated by light. We studied the photodegradation of CA upon controlled exposure to UVB-UVA irradiation by multiple techniques, including GC-MS, UHPLC-PDA-ESI-MS/MS and by direct infusion in ESI-MSn, which were matched to in silico mass spectral simulations to identify degradation products. Seven byproducts formed upon UVA exposure for 3 h at 70 mW/cm2 (blue-to-green color change) were identified, including CA dimers and CA benzenoid, which were not found on extended 6 h irradiation (green-to-yellow fading). Photostability tests with reduced irradiance conducted in various solvents in the presence/absence of air indicated highest degradation in acetonitrile in the presence of oxygen, suggesting a photo-oxidative mechanism. Testing in the presence of antioxidants (tocopherol, ascorbyl palmitate, hydroxytyrosol, bakuchiol, γ-terpinene, TEMPO and their combinations) indicated the highest protection by tocopherol and TEMPO. Sunscreens ethylhexyl methoxycinnamate and particularly Tinosorb® S (but not octocrylene) showed good CA photoprotection. Thermal stability tests indicated no degradation of CA in acetonitrile at 50 °C in the dark for 50 days; however, accelerated degradation occurred in the presence of ascorbyl palmitate.