DOCSLIB.ORG

Antioxidants for the Stabilization of Sunscreen

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Antioxidants for the Stabilization of Sunscreen COSMETICS SUNSCREEN K. Jung, M. Seifert, Th. Herrling* Antioxidants for the Stabilization of Sunscreen ■ Introduction However, these inorganic UV filters also Minerals such as titanium dioxide, TiO2, absorb considerable UV-radiation. and zinc oxide, ZnO, are well known ac- To preclude sunburns and protect people tive semiconductor photocatalysts used from serious skin damage, sunscreens extensively in heterogeneous photo- must possess several attributes. They catalysis to destroy environmental pol- have to be photostable (ideally 100%) lutants that are organic in nature. They and they have to dissipate the absorbed are also extensively used in sunscreen lo- energy efficiently through photophysi- Abstract tions as active broadband sunscreens cal and photochemical pathways that that screen both UVB (290-320 nm) and rule out the formation of singlet oxygen, ifferent sunscreen formula- UVA (320-400 nm) sunlight radiation and other reactive oxygen species, and other as high SPF makers. When so photoacti- tions have been investigated harmful reactive intermediates (Fig. 1). vated by UV light, however, these two Dregarding their radical gen- particular metal oxides are known to eration under UV radiation. Organic generate highly oxidizing radicals (•OH -• and inoraganic UV-filter molecules and O2 ) and other reactive oxygen can generate free radicals during species (ROS) such as H2O2 and singlet oxygen, 1O , which are known to be cy- UV-radiation. Whereas organic UV- 2 totoxic and/or genotoxic. Hydroxyl(•OH) filters are marked by their degrada- radicals photogenerated from photoac- tion under UV-light, inorganic filters tive TiO2 specimens extracted from com- are marked by their photocatalytic mercial sunscreen) induce damage to DNA reactions. The generation of free plasmids in vitro and to whole human radicals inside a cosmetic formula- skin cells in cultures. tion leads to the de-stabilization of In contrast to the physical UV-blockers, Fig. 1 The generation of free radicals chemical UV absorbers have to convert the entire cosmetic preparation. by adsorption of an electron the UV light into chemical energy. During Antioxidants can help to overcome this conversion and the following molec- They should not penetrate the skin, and this problem, neutralizing the UV- ular re-arrangements, the excited mole- should not be transported into the hu- induced free radicals. Polyphenolic cules formed by absortion of UV radiation man cells where they can cause delete- compounds, as Green tea extracts, return to the basal state by different ra- rious damage to DNA. Sunscreens should are efficient radical quenchers. The diative and non-radiative decay mecha- also minimize the extent of UVB and UVA nisms. Some of these mecanisms can af- amount of radicals generated with radiation that might reach DNA in cell fect their activity, leading to the forma- nuclei (1-4). With few exceptions, sun- and without the addition of anti- tion of new compounds by photoaddition, screens contain chemical filters (organ- oxidants can be quantified by Elec- substitution, cycloaddition, isomerization, ic; absorb mostly UVB radiation) and tron Spin Resonance (ESR) spec- photofragmentation reactions, etc. The physical filters (e.g., TiO2 and ZnO). The troscopy and is expressed by the molecular re-arrangements are strongly latter have been said to blockUVB/UVA Radical Generationg Factor (RGF). depending on the chemical environment sunlight through reflection and scatter- of the UV-blockers, on their solvent com- ing (5, 6). If this were so, since reflection pounds, purity, and concentration. and scattering are physical phenomena, These new compounds can be inactive the term physical UV filters was coined. (they do not absorb the UV radiation) or 2 SOFW-Journal | 138 | 10-2012 COSMETICS SUNSCREEN favor the degradation of other com- ■ Materials and Methods (2,2,5,5 tetrametylpyrrolidine-N-oxyl - pounds present inside the formulation. PCA). The RGF (Radical Generating Fac- In both cases, the photoprotective effect Chemicals tor) shows the increase of generated free of the sunscreen is compromised. The nitroxide 2,2,5,5 tetrametylpyrroli- radicals indicated as a percentage (%). Eleven commercial sunscreen were test- dine-N-oxyl (PCA) was obtained from ed (7, 8) for their free radical generation Sigma-Aldrich (Germany). A final con- UV irradiation during UV-radiation. The results are ex- centration of 1 mM PCA solution was The UV-irradiation was performed with pressed in percentage as Radical Gener- used. xenon arc lamp Solar Simulator from ating Factor (RGF). The aim of the pre- Eleven different sunscreens (market prod- Newport-ORIEL Product Line 81260 (US, sent study was the characterization of ucts) were used. The content of the UV- Newport Solar Simulators – product speci- the radical generation inside the formu- filter is indirect proportional to the or- fications) equipped with a 300W Xenon lations and the radical reduction due to dinal number. All containing UV-filters lamp supplying an irradiance in the plane antioxidants. Therefore, five antioxida- in an unknown concentration and are of the sample of 16,5 mW/ cm2 for UVA tive raw materials (tocopherol, green tea marked in the INCI declaration (Table 1). (330-400 nm) and 5,0 mW/cm2 for UVB extract, honeybush extract, pomegran- Antioxidants green tea, pomegranate, (290-330 nm). The 81260 has a UVB/UVA ate extract, and rooibos extract) typical- honeybush, and rooibos extract ido- dichroic mirror as a standard device. It ly used in cosmetic formulations (9), were neous for cosmetic preparations were passes 280 to 400 nm and greatly re- added to the tested sunscreens and the purchased from different suppliers. D-α- duces the VIS and IR output of the lamp. radical formation during UV-exposure tocopherol was purchased from Sigma- The measurements were performed with was determined. The antioxidative pow- Aldrich (Munich, Germany) at the high- an UV-Meter-BASIC (hönle UV technolo- er (AP) of the cosmetics was determined est purity grade available. gy, Germany). The UV solar simulator by an ESR spectroscopy method (10). The emits a continuous spectrum with no comparison between the amounts of Free radical indicator gaps or extreme peaks of emission in the free radicals generated with and without Oxygen and carbon centered free radi- UV region. The output from the solar antioxidants led to a rating of antiox- cals generated in skin during UV irra- simulator is stable, uniform across the idative actives that might be useful for diation were detected by using a radical whole output beam and suitable filtered the stabilization of sunscreen products. trap on the basis of nitroxyl compounds to create a spectral quality that complies Code SPF TiO2 BMDBM OC EHS BEMT EHT TDSA HS PBSA DHHB EHMC A 25 3 4 1 2 B 25 3 2 1 4 5 C 30 3 4 1 2 D 30 3 4 1 2 E 30 2 1 3 F 50+ 2 3 1 G 20 3 2 1 H202431567 I 15 3 4 1 2 J 30 3 2 1 4 K 50+ 5 2 1 3 4 6 7 8 List of abbreviation BEMT Bis-Ethylhexyloxyphenolmethoxyphenyl triazine EHT Ethylhexyl triazone BMDM Butyl methoxydibenzoylmethane HS Homosalate DHHB Diethylamino Hydroxybenzoyl Hexyl Benzoate OC Octocrylene EHMC Ethylhexyl methoxycinnamate PBSA Phenylbenzimidazole sulfonic acid EHS Ethylhexyl salicylate TDSA Terephtalylidene dicamphorsulfonic acid Table 1 UV-ilter content for eleven assorted sunscreen 4 SOFW-Journal | 138 | 10-2012 COSMETICS SUNSCREEN with the required acceptance limits. The RCEE% values are in the acceptance lim- Unpaired Electron its. Antioxidant ESR Spectrometer A X-band ESR spectrometer Miniscope 300 Magnettech GmbH, Berlin, Germany was used for in vitro detection of free Electron radicals. A conventionel quartz tube with Donation a inner diameter of 1 mm from Mag- nettech for aques measurements was applied. Experimental process 500 mg of the sunscreen were solved in Free Radical 1000 mg of distilled water. 15 µl of 10 mM PCA were mixed under continuous stir- ring during UV-irradiation with the so- Fig. 2 The effect of antioxidants for neutralizing of free radicals lar simulator. The PCA signal is measured before and after the UV irradiation of 5 minutes. The signal is reduced if free radicals are reduce the amount of UV-induced free Different antioxidants were used which generated. If the signal is not reduced radicals. have a dfferent AP (10). (RGF = 0), there is no generation of free 50 mg of the antioxidant stock solutions radicals. (10% concentrated in water) were added ■ Results The addition of antioxidants (9) can give to 450 mg of the sunscreen. This prepa- the atom the missing electron back to fill ration was added to 1000 mg of water. Table 2 shows the RGF values (%) of 11 in the electrons (Fig. 2). Adding antioxi- The final antioxidant concentration in products, which can be divided into two dants to the sunscreen formulation can the samples was 0.3 %. main groups concerning their radical RGF (%) Antioxidants added to the final formulations Code SPF Pure Honey Bush Vit. E Green Tea Pomegranate Rooibos product Extract (Toco.) Extract Extract Extract 1% 1% 1% 1% 1% AP(AU) 0 10.290 40.400 112.400 70.955 10.788 tr(min) - 0,97 0,33 0,33 0,40 0,72 A 25 22 11 20 0 13 10 B 25 28 18 21 0 16 12 C 30 25 12 25 0 14 9 D 30 25 10 25 0 10 5 E 30 26 20 22 0 15 4 F 50+ 25 8 20 0 17 13 G 20 10 2 10 0 10 10 H20000 000 I 15 10 6 10 0 15 10 J 30 3 0 5 0 3 3 K 50+ 5 1 3 0 3 0 Table 2 RGF(%) after 5’ UV and application of antioxidants 6 SOFW-Journal | 138 | 10-2012 COSMETICS SUNSCREEN generation during UV-irradiation. The The three hydrophilic organic antioxi- ic UV blocker, on the combination of or- products in the first group marked by the dants honey bush with AP=102.900; tr= ganic UV-filters, and on the formulation capital letters A-F show a radical gener- 0,97min; pome granate with AP=709.550; properties.
Load more

Recommended publications
  • Download Booklet
    www.mmsus.com | 952.525.2005 COVID-19 PRODUCTS Midwest Mechanical Solutions is your partner in optimizing your building for a safe, healthy, and comfortable environment for all. Contact your MMS Representative at any time, we are here to help. Advanced HEPA Filtration Recirculation/Negative Pressure Units AF400NP 1400 cubic foot room / 280 CFM • Air Flow: Nominal 132 l/s / 280 CFM • Voltage: 120V (2A) or 230V (1A) • Dimensions: 21"H x 13"W x 16"D / 55cm x 33cm x 40cm • Filtration: 2” Pre-lter MERV10 6” Medical grade HEPA lter 99.97% (to 0.3 micron) • Optional: chemical lter • Inlet: Bottom inlet • Discharge: 4” Discharge collar • Exhaust kit included • Sound Level: Whisper quiet, 56 dBA • Controls: Remote ON/OFF, communication capabilities, audible and visual alarms AF1000NP 3000 cubic foot room / 600 CFM • Air Flow: Nominal 283 l/s / 600 CFM • Voltage: 120V (2A) or 230V (1A) • Dimensions: 56"H x 16"W x 22"D / 132cm x 40cm x 56cm • Filtration: 2” Pre-lter MERV10 12” High capacity pleated lter MERV12 6” Medical grade HEPA lter 99.97% (down to 0.3 micron) • Optional: chemical lter (up to 50 lbs./23 kg) • Inlet: Bottom inlet • Discharge: 6” Discharge collar (4”, 8” optional) • Exhaust kit included • Sound Level: Whisper quiet, 54 dBA Controls: • Remote ON/OFF, communication capabilities, audible and visual alarms AF2000NP 5000 cubic foot room / 1000 CFM • Air Flow: Nominal 283 l/s / 600 CFM • Voltage: 120V (2A) or 230V (1A) • Dimensions: 56"H x 16"W x 22"D / 132cm x 40cm x 56cm • Filtration: 2” Pre-lter MERV10 12” High capacity pleated lter
    [Show full text]
  • A Thesis Entitled Evaluating UVB and UVA Boosting Technologies For
    A Thesis entitled Evaluating UVB and UVA Boosting Technologies for Chemical and Physical Sunscreens by An Ngoc Hiep Huynh Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Pharmaceutical Sciences Industrial Pharmacy ___________________________________________ Gabriella Baki, Ph.D., Committee Chair ___________________________________________ Jerry Nesamony, Ph.D., Committee Member ___________________________________________ Matthew W. Liberatore, Ph.D., Committee Member ___________________________________________ Dr. Amanda C. Bryant-Friedrich, Dean College of Graduate Studies The University of Toledo May 2020 Copyright 2020 An Ngoc Hiep Huynh This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author. An Abstract of Evaluating UVB and UVA Boosting Technologies for Chemical and Physical Sunscreens by An Ngoc Hiep Huynh Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Pharmaceutical Sciences Industrial Pharmacy The University of Toledo May 2020 There are currently 14 organic and 2 inorganic UV filters approved in the United States. Due to coral reef safety concerns, octinoxate and oxybenzone have been banned in Hawaii, Key West, FL and the US Virgin Islands; and octocrylene is also being studied for its potential impact on coral reef safety, leaving 11 organic UV filters as viable options for sunscreen manufacturers – with limitations on their combination. Since consumers are always looking for sunscreens with high SPF and broad-spectrum protection, the need for UVB and UVA protection boosting technologies is greater than ever. In a preliminary study, about two dozen emollients were scanned for their SPF boosting capability with selected organic UV filters.
    [Show full text]
  • Sunscreen Enhancement of Octyl Methoxycinnamate Microcapsules by Using Two Biopolymers As Wall Materials
    polymers Article Sunscreen Enhancement of Octyl Methoxycinnamate Microcapsules by Using Two Biopolymers as Wall Materials Chuntao Xu 1,2 , Xuemin Zeng 3, Zujin Yang 4,* and Hongbing Ji 1,3,4,5,* 1 School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China; [email protected] 2 School of Information Engineering, Zhongshan Polytechnic, Zhongshan 528400, China 3 Fine Chemical Industry Research Institute, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, China; [email protected] 4 School of Chemical Engineering and Technology, Sun Yat-Sen University, Zhuhai 519082, China 5 School of Chemical Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, China * Correspondence: [email protected] (Z.Y.); [email protected] (H.J.) Abstract: Octyl methoxycinnamate (OMC) is widely used as a chemical sunscreen in sunscreen cosmetics. However, its direct contact with the skin would bring certain risks, such as skin photo- sensitive reaction. How to improve the effect of skin photodamage protection has become a current research hotspot. Encapsulating ultraviolet (UV) filters into microcapsules is an interesting method to increase the photostability of filters. In this study, sodium caseinate (SC) and arabic gum (GA) are chosen as wall materials to prepare synergistic sunscreen microcapsules by complex coacervation technology. A series of experiments are conducted to investigate the effects of pH, wall material concentration, and wall/core ratio on the formation of OMC microcapsules. The morphology, com- position, and stability of OMC microcapsules are characterized by scanning electron microscopy Citation: Xu, C.; Zeng, X.; Yang, Z.; Ji, (SEM), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA).
    [Show full text]
  • Salicylate UV-Filters in Sunscreen Formulations Compromise the Preservative System Efficacy Against Pseudomonas Aeruginosa and Burkholderia Cepacia
    cosmetics Article Salicylate UV-Filters in Sunscreen Formulations Compromise the Preservative System Efficacy against Pseudomonas aeruginosa and Burkholderia cepacia Noa Ziklo, Inbal Tzafrir, Regina Shulkin and Paul Salama * Innovation department, Sharon Laboratories Ltd., Odem St. Industrial zone Ad-Halom, Ashdod 7898800, Israel; [email protected] (N.Z.); [email protected] (I.T.); [email protected] (R.S.) * Correspondence: [email protected]; Tel.: +972-54-2166476 Received: 15 July 2020; Accepted: 1 August 2020; Published: 3 August 2020 Abstract: Contamination of personal-care products are a serious health concern and therefore, preservative solutions are necessary for the costumers’ safety. High sun protection factor (SPF) sunscreen formulations are known to be difficult to preserve, due to their high ratio of organic phase containing the UV-filters. Salicylate esters such as octyl salicylate (OS) and homosalate (HS) are among the most common UV-filters currently used in the market, and can undergo hydrolysis by esterase molecules produced by contaminant microorganisms. The hydrolysis product, salicylic acid (SA) can be assimilated by certain bacteria that contain the chorismate pathway, in which its final product is pyochelin, an iron-chelating siderophore. Here, we show that OS and HS can compromise the preservative efficacy against two pathogenic important bacteria, Pseudomonas aeruginosa and Burkholderia cepacia. Challenge tests of formulations containing the UV-filters demonstrated that only bacteria with the chorismate pathway failed to be eradicated by the preservation system. mRNA expression levels of the bacterial pchD gene, which metabolizes SA to produce pyochelin, indicate a significant increase that was in correlation with increasing concentrations of both OS and HS.
    [Show full text]
  • Cutaneous Permeation and Penetration of Sunscreens: Formulation Strategies and in Vitro Methods
    cosmetics Review Cutaneous Permeation and Penetration of Sunscreens: Formulation Strategies and In Vitro Methods Silvia Tampucci * ID , Susi Burgalassi ID , Patrizia Chetoni ID and Daniela Monti ID Department of Pharmacy, University of Pisa, 56126 Pisa, Italy; [email protected] (S.B.); [email protected] (P.C.); [email protected] (D.M.) * Correspondence: [email protected] Received: 1 November 2017; Accepted: 7 December 2017; Published: 25 December 2017 Abstract: Sunscreens are the most common products used for skin protection against the harmful effects of ultraviolet radiation. However, as frequent application is recommended, the use of large amount of sunscreens could reflect in possible systemic absorption and since these preparations are often applied on large skin areas, even low penetration rates can cause a significant amount of sunscreen to enter the body. An ideal sunscreen should have a high substantivity and should neither penetrate the viable epidermis, the dermis and the systemic circulation, nor in hair follicle. The research of methods to assess the degree of penetration of solar filters into the skin is nowadays even more important than in the past, due to the widespread use of nanomaterials and the new discoveries in cosmetic formulation technology. In the present paper, different in vitro studies, published in the last five years, have been reviewed, in order to focus the attention on the different methodological approaches employed to effectively assess the skin permeation and retention of sunscreens. Keywords: sunscreens; formulation; in vitro methods; cutaneous permeation; skin penetration 1. Introduction The detrimental effects of human exposure to ultraviolet (UV) radiation have been widely investigated and can be immediate, as in the case of sunburns, or long-term, causing, in most cases, the formation of oxidizing species responsible of photo-aging, immunosuppression and chronic effects such as photo carcinogenicity [1,2].
    [Show full text]
  • SUNCAPS™ Unbreakable and Transparent Encapsulated UV Filters Range
    ™ Non-breakableSUNCAPS transparent microcapsules containing UV filters, ideal for all cosmetic formulations Leader in Microencapsulation Technology SUNCAPS™ Unbreakable and Transparent Encapsulated UV Filters Range This range includes: AvoCapTM encapsulated Avobenzone 56% payload and 14% of Octocrylene AvoCap2TM encapsulated Avobenzone, 53% payload OmcCapTM encapsulated Octyl Methoxycinnamate, 60% payload HomCapTM encapsulated Homosalate, 60% payload OctiCapTM encapsulated Octisalate 60% payload OctoCapTM encapsulated Octocrylene, 52% payload Cellu™ ZinoCap encapsulated ZnO, 70% payload Cellu™TitanCap encapsulated TiO2, 70% payload Tagra’s unique patented microencapsulation technology (US Patent Application No. 61/770,773) enables the manufacturing of a “green” unbreakable, transparent micron size microcapsules of organic and inorganic UV filters. This delivery system will: ° Prevent the UV filter leakage into the surrounding ° Retain the sunscreen on the superficial layers of the skin ° Improve safety profile - no risk of skin penetration and no skin irritatioin and/or photoallergy ° Enhance UV filters chemical stability and photostability ° Overcome incompatibilities between or among UV filters allowing new sunscreen combinations ° Prevent the crystallization of Avobenzone ° Enable UV filters dispersibility in water phase ° Prevent appearance of white residues caused by TiO2 and ZnO ° Avoid need for UV filters solubilizers, therefore enabling light, aesthetic, gentle, smooth and non-greasy feel formulations ° SunCapsTM exhibit improved sensorial profile with better tactile properties SunCaps™ microcapsules are made of a single layer Cellulose based polymer shell which provides optimal isolation of the UV filter and prevents its degradation while improving its UV protection profile (Figure.1 and Table.1). SUNCAPS™ SIGNIFICANTLY INCREASE UV FILTERS PHOTOSTABILITY AND OVERCOME INCOMPATIBILITIES 70 60 A. B. 60 50 50 40 30 40 20 10 Residual OMC (%) Residual 30 (%) Avobenzone Residual 0 TM Free OMC OmcCapTM Free Avobenzone AvoCap Figure.1.
    [Show full text]
  • All About Safety UV C Hazards and Risks
    All about Safety: UV-C Hazards and Risks Authored by: Ye Zhang, PE; Joyce Kelly, R.A., GLHN Architects & Engineers, Inc. One hundred years of increasingly effective germicidal UV light irradiance has helped mitigate infectious transmission within buildings. Our last paper, “The Ins & Outs of UV-C Germicidal Irradiation” examined how UV-C breaks down the RNA of viruses like Covid-19 in a range of applications including HVAC systems and can treat upper room air. Until the 1990’s however, the hazards were largely ignored. The safety data has accumulated to warrant its own paper. UV-C devices have proliferated - especially since the pandemic – to clean everything from hospital and motel rooms to phones and PPE. UV-C can be a miracle agent of disinfection - with careful design and caution. Users may not realize the danger until after exposure has caused damage four to 24 hours afterwards. Chronic effects are long-lasting and cumulative and may not appear for years including skin cancer and ocular cataracts.1 In addition, new health challenges related to ozone damage from far UV-C sources require careful design and regulation. The FDA highlighted the risks in their Feb. 27, 2020 Safety communication focused on CPAP medical devices.2 Accidental or lengthy exposure to UV light while it is cleaning can put a user at risk of eye injury, skin burns or an increased risk of skin cancer – while being unable to penetrate and disinfect all areas of hoses, masks and connectors. At a larger scale, upper air UV-C requires design with safety interlocks, an understanding of surface reflectivity, and may require a thermodynamic analysis of air movement in complex spaces to ensure effectiveness.
    [Show full text]
  • HIGH PERFORMING TITANIUM DIOXIDE DISPERSIONS (Continued)
    HigH PE rForming titAnium DioXiDE DiSPEr SionS leveraging a new patented coating system and pure photostability science introDuCtion HIGH PERFORMING Metal oxides with a wide band gap, such as Titanium Dioxide (TiO 2), or with a direct band gap, such as Zinc Oxide (ZnO), absorb and reflect UV energy from the sun’s radiation. This makes TITANIUMthem useful as UV filters and as DIOXIDE pigments in the cosmetic industry. Unfortunately, they are also photo-active, promoting the formation of reactive oxygen species and catalyzing the decomposition of organic materials. This is not desiredDISPERSIONS in personal care applications, where the protective functions of these organic compounds are needed. CommercialLEVERAGING surface modifications A NEW have PATENTED not eliminated COATING this degradation, so a new means of protection was needed. SYSTEM AND PURE PHOTOSTABILITY SCIENCE Solution Metal oxides with a wide band gap, such as titanium dioxide Hallstar has developed (derived from dimethiconol) UV filter dispersions with our market leading (TiO ), or with a direct band gap, such as zinc oxide (ZnO), HallStar has developed UV filter dispersions highlighting both the benefits of2 photo-protected Titanium Dioxide and an highlighting both the photostabilizer technology, ® industry leading mineral UV filter aesthetic. Leveraging a patent-protected C3+absorb coating and reflect system UV consistingenergy from the of sun’sSilica radiation. moieties This benefits of photo- SolaStay S1 (ethylhexyl (derived primarily from Tetraorthosilicate), Alkyl groups (derived from Triethoxycaprylylsilane)makes them useful as UV filtersand Polydimethylsiloxaneand as pigments in the protected titanium dioxide methoxycrylene) and and an industry leading HallBrite® BHB (butyloctyl (derived from Dimethiconol) with our market leading photostabilizer technology, SolaStay ® S (Ethylhexyl Methoxycrylene) cosmetic industry.
    [Show full text]
  • Chemical and Dermatological Aspects of UV-Absorbing Compounds
    Chemical and Dermatological Aspects of UV‐absorbing Compounds Studies of Photoallergens and Synthesis of a Natural UV‐filter ISABELLA KARLSSON DOCTORAL THESIS Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemistry Chemical and Dermatological Aspects of UV‐absorbing Compounds Studies of Photoallergens and Synthesis of a Natural UV‐filter ISABELLA KARLSSON Cover illustration: Proposed mechanism for activation of the commercial UV‐filters 4‐tert‐ butyl‐4’‐methoxy dibenzoylmethane and octocrylene by solar radiation resulting in the reaction with skin proteins and the formation of immunogenic complexes. © Isabella Karlsson ISBN: 978‐91‐628‐8349‐2 Available online at: http://hdl.handle.net/2077/26665 Department of Chemistry University of Gothenburg SE‐412 96 Göteborg Sweden Printed by Chalmers Reproservice Göteborg, Sweden, 2011 The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found if!) but ‘That’s funny…’ Isaac Asimov (1920‐1992) ABSTRACT The sun’s UV radiation is necessary for the existence of life on earth. However, too much UV exposure can lead to the development of skin cancer. Therefore, sunscreens are often used by the general population as protection from excessive UV radiation. Unfortunately, many of the chemical UV‐filters that are used in sunscreens today have the ability to induce contact and photocontact allergy. In this work two different chemical UV‐filters together with the anti‐inflammatory drug ketoprofen, all known to induce allergic reactions, have been studied to better understand the reason for these adverse effects. In addition, a synthetic route to the natural UV‐filter scytonemin has been developed.
    [Show full text]
  • Current Problems in the Use of Organic UV Filters to Protect Skin From
    Current problems in the use of organic UV fi lters to protect skin from excessive sun exposure Zuzana Klimová, Jarmila Hojerová, Silvia Pažoureková Institute of Biotechnology and Food Science, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, 812 37 Bratislava, Slovak Republic [email protected] Abstract: The evidences of the harmful effects of skin exposure to excessive UltraViolet (UV) radiation, primarily on the development of skin cancer, have increased over the last decade. Therefore, national and international health authorities have encouraged the public to take protective sunscreens, and respectively also everyday cosmetics containing UV fi lters. In these products, a mixture of the UV fi lters, including both inorganic and organic nature, has been shown to be more effective than the individual UV fi lter. However, cur- rently there are concerns about the safety and actual effectiveness of some UV fi lters; especially about certain UV-absorbing compounds (organic UV fi lters). Three cardinal problems are the most questionable. First, that certain UV fi lters are absorbed through the skin resulting in systemic exposure with unknown consequences. Second, that certain UV fi lters show the potential to be adversely endocrine disruptors. Third, that certain UV fi lters are partially degraded by UV radiation, what making them photounstable and unable to fulfi l their basic protective function. The purpose of this article is to discuss these problems. Keywords: sunscreens, organic UV fi lters, endocrine disruptors, dermal absorption, photostability, safety Introduction in the United States they are considered Over-the- Counter (i.e. non-prescription) drug products (FDA, Exposure of the human body to sunlight especially 2011).
    [Show full text]
  • Photolytic and Photocatalytic Degradation of Organic UV Filters
    ACCEPTED MANUSCRIPT UV filters Removal technologies Use in personal care products formulations Biological Physical treatment Chemical treatment treatment processes e.g. reverse Hybrid processes processes processes osmosis, adsorption, Personal use on skin membrane separation Degradation by ozonation, catalysis, halogination, hypochlorite treatments, free Protect from UV radical treatments such as hydroxyl etc. Associated secondary irradiation risks/ impacts/ n environmental fate Advanced chemical o i t processes such as a d Transport to aquatic photolysis, photocatalysis , a r Degradation byproducts environment g photolysis in H 2O2 e d o t o h Associated risks/ impact/ P Future research need environmental fate MANUSCRIPT ACCEPTED ACCEPTED MANUSCRIPT 1 Photolytic and Photocatalytic Degradation of Organic UV Filters 2 in Contaminated Water 3 4 5 Mohammad Boshir Ahmed, Md Abu Hasan Johir, John L Zhou*, Huu Hao Ngo, Wenshan 6 Guo, Kireesan Sornalingam 7 8 9 School of Civil and Environmental Engineering, University of Technology Sydney, 15 10 Broadway, NSW 2007, Australia 11 12 13 14 MANUSCRIPT 15 16 17 Corresponding author: 18 Prof John L Zhou 19 School of Civil and Environmental Engineering 20 University of Technology Sydney 21 15 Broadway, NSWACCEPTED 2007 22 Australia 23 Email: [email protected] 24 1 ACCEPTED MANUSCRIPT 25 Abstract 26 UV filters as emerging contaminants are of great concern and their wide detection in aquatic 27 environments indicates their chemical stability and persistence. This review summarized the 28 photolytic and photocatalytic degradation of UV filters in contaminated water. The findings 29 indicated that limited research has been conducted on the photolysis and photocatalysis of UV 30 filters.
    [Show full text]
  • UVA Chemical Filters
    UVA Chemical Filters: A Systematic Study Jacqueline F. Cawthray, B. Science (Hons) A thesis submitted for the degree of Doctor of Philosophy in The University of Adelaide Department of Chemistry February 2009 Chapter 1 1 Introduction Sunlight, incorporating ultraviolet radiation, provides the energy necessary to sustain life. Ultraviolet radiation (UVR) is the non-visible part of the solar spectrum incorporating the wavelengths between 100 and 400 nm. Wavelengths in the ultraviolet region of the spectrum are further subdivided into UVA, UVB and UVC. The physiological responses to UVR can be both beneficial and harmful. Small doses of UV are required to produce vitamin D and in some cases therapeutic improvements are observed for skin disorders. However, long and short-term exposure can cause a variety of detrimental biological effects in humans. The biological effects of UVB have been intensively researched and are largely well understood. Armed with this knowledge, public attitudes have changed accordingly. The bronzed Aussie is no longer the national icon he or she once was, as the use of sun protection methods, including sunscreens, has now become common practice. Until recently, UVA was believed to play little or no role in the damaging effects of UVR and was often neglected in studies. However, there is now accumulating evidence that UVA plays a major role in sunlight-induced damage. As information regarding the detrimental effects of UVA increases, there needs to be an accompanying increase in public awareness regarding the potential hazards and the need for sunscreen filters that protect skin from UVA wavelengths has become a current issue of importance.
    [Show full text]