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Granger C, Trullàs C, Sokeechand NB, Jourdan E, Krutmann J, Francois-Newton V, Hosenally M. Evaluating the factors influencing sun protection factors (SPF): Pooling data from multiple studies involving two reference ISO 24444:2019 sunscreen products (P2 and P8). PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE 2024; 40:e12942. [PMID: 38288771 DOI: 10.1111/phpp.12942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 11/27/2023] [Accepted: 12/12/2023] [Indexed: 02/01/2024]
Abstract
BACKGROUND Standardized methods for sun protection factor (SPF) testing are still beset with endpoint and method-driven issues, and can be influenced by multiple factors. The purpose of this analysis is to explore the factors influencing the results of sun protection factor (SPF) testing in human subjects according to the ISO 24444:2019 standard. Intrinsic factors, such as baseline skin color, age and gender, the minimal erythemal dose on an unprotected area (MEDu), as well as environmental factors such as season/weather influences, are considered for analysis. METHODS Datasets generated for two reference products (P2 and P8) during the conduct of 50 such studies using the ISO standard 24444:2019 for the testing of SPF products, from a single testing center located in Bucharest, Romania between April 2021 and December 2022, were retrieved and compiled. Overall, the data for 334 subjects was available, with 276 observations for the reference P8, and 171 for P2. RESULTS No effects due to gender or age were detected. Seasonal changes, the individual typology angle (ITA°) and MEDu were found to have an influence on the outcome of the SPF values. CONCLUSIONS This study adds new original data about the impact of intrinsic and extrinsic factors on SPF variations pertaining to ISO reference sunscreen P8 (SPF 50+). The findings suggest that some factors will inevitably impact the results between two SPF experiments for the same product and SPF testing laboratory. The interconnections between the sources of this variation are discussed. The findings of this research help to identify and characterize factors that contribute to SPF testing variability.
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Affiliation(s)
| | | | | | - Eric Jourdan
- Innovation and Development, ISDIN, Barcelona, Spain
| | - Jean Krutmann
- IUF Leibniz Research Institute for Environmental Medicine, Dusseldorf, Germany
- Medical Faculty, Heinrich-Heine-University, Dusseldorf, Germany
| | | | - Muzzammil Hosenally
- Centre International de Développement Pharmaceutique (CIDP), Phoenix, Mauritius
- Department of Economics and Statistics, University of Mauritius, Réduit, Mauritius
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2
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Qu D, Liao F, Liu J, Li X, Ye C, Zheng Y, Xie X, Yi J, Lai W. The dose response of erythemal area and intensity on the unprotected skin fits well to a logistic 3P model in SPF tests of a Chinese population, which has the potential to improve the precision and consistency of minimal erythema dose determination. PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE 2023; 39:633-641. [PMID: 37667596 DOI: 10.1111/phpp.12909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 08/08/2023] [Accepted: 08/10/2023] [Indexed: 09/06/2023]
Abstract
BACKGROUND The current ISO guidelines for minimal erythema dose (MED) determination require assessment of erythema area of UV-irradiated skin sites. However, this parameter has not been adequately quantified in daily practice. The aims of this study were to investigate the dose response on the unprotected skin sites by quantifying the erythema area and intensity and to show the potential for improving the precision and consistency of MEDu determination by developing predictive models. METHODS Standard radiation tests were conducted on the back of 31 healthy Chinese volunteers and the MEDu site of each subject was clinically determined by dermatologists. Images of test sites were captured 24 h after radiation, and the erythema area (%EA) and intensity (∆a*) were measured by image analysis. The data were fitted to a logistic 3P function to obtain dose-response curves, and a set of logit (inverse-logistic) models were then derived. An erythema area threshold of %EA = 52% was established to predict MEDu based on the clinical endpoints defined by ISO 24444:2019. RESULTS Analysis of the clinically determined MEDu sites revealed wide ranges of %EA (62.3 ± 15% SD) and ∆a* (2.96 ± 0.92 SD). The dose response fitted well to a logistic 3P model (mean R2 = 0.965 and 0.975 for %EA and ∆a*, respectively). Applying the area threshold, values of MEDu were determined by the logit model for the test population, which significantly improved the consistency of MEDu determination (52 ± 0% SD and 2.73 ± 0.61 SD for %EA and ∆a*, respectively). CONCLUSION This study demonstrated that the dose response of UV-induced erythema can be quantified and modeled once the erythema area and intensity are measured. The results of this study show the potential to improve the precision and consistency of MEDu determination in an SPF test. The similar potential in photodermatological, therapeutic, and diagnostic applications was also implied.
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Affiliation(s)
- Di Qu
- Amway Innovation & Science, Ada, Michigan, USA
| | - Feng Liao
- Amway (Shanghai) Innovation & Science Center, Shanghai, China
| | - Jianwei Liu
- Amway (Shanghai) Innovation & Science Center, Shanghai, China
| | - Xiangzi Li
- Department of Dermatology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Congxiu Ye
- Department of Dermatology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Yue Zheng
- Department of Dermatology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Xiaoyuan Xie
- Department of Dermatology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Jinling Yi
- Department of Dermatology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Wei Lai
- Department of Dermatology, The Third Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
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Granger C, Passeron T, Trullas C, Hosenally M, Sokeechand BN, Krutmann J, Lim HW. Outdoor clinical testing with reference sunscreens to determine differences in skin response between populations of different ethnicity: A combined data analysis from 128 subjects. PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE 2023; 39:419-427. [PMID: 36867064 DOI: 10.1111/phpp.12871] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/22/2023] [Accepted: 02/27/2023] [Indexed: 03/04/2023]
Abstract
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.
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Affiliation(s)
| | - Thierry Passeron
- Department of Dermatology, CHU Nice, Côte d'Azur University, Nice, France
- C3M, INSERM U1065, Côte d'Azur University, Nice, France
| | | | - Muzzammil Hosenally
- Centre International de Développement Pharmaceutique (CIDP), Phoenix, Mauritius
- Department of Economics and Statistics, University of Mauritius, Réduit, Mauritius
| | | | - Jean Krutmann
- IUF Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
- Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Henry W Lim
- Photomedicine and Photobiology Unit, Department of Dermatology, Henry Ford Health System, Detroit, MI, USA
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4
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Bacardit A. Determining the ability to differentiate results between independent sun protection factor tests using the ISO24444 method. Front Med (Lausanne) 2023; 10:1042565. [PMID: 36891187 PMCID: PMC9986478 DOI: 10.3389/fmed.2023.1042565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 02/06/2023] [Indexed: 02/22/2023] Open
Abstract
Introduction The sun protection factor has nowadays become a familiar metric to understand sunscreen effectiveness. This value is displayed on the label of sunscreens and it is established by translating the results obtained from standardized testing methods to regulatory labeling criteria. The ISO24444, a widely accepted method to measure the sun protection factor, is designed to determine the validity of a single test, but it lacks criteria to compare results and many regulators only endorse the method as a valid means to label sunscreens. This supposes a challenge for manufacturers and regulators routinely using the method to take decisions on product labeling when confronted with disparate results for the same product. Methods Analytical review of the statistical criteria used by the method to determine test validity. Results For the same product, results from independent tests (of 10 subjects each) separated less than ×1.73 can be considered as the same from the point of view of compliance to the standard. Conclusion This range of sun protection factor values far exceeds the ranges for labeling and categorizing sunscreens as per current regulations and thus opens the possibility that sunscreens are unknowingly mislabeled. These findings can be summarized in a "discriminability map" to assist comparing results from different tests and to better inform the labeling of sunscreen products and thus increase confidence to prescribers and consumers.
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Kobylinski S, Reble C, Schanzer S, Gersonde I, Wiora G, Lobo Ploch N, Karrer H, Kolbe L, Khazaka G, Lademann J, Meinke MC. Noninvasive measurement of the 308 nm LED-based UVB protection factor of sunscreens. JOURNAL OF BIOPHOTONICS 2021; 14:e202000453. [PMID: 33423394 DOI: 10.1002/jbio.202000453] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/21/2020] [Accepted: 01/06/2021] [Indexed: 06/12/2023]
Abstract
The current method for determining the sun protection factor (SPF) requires erythema formation. Noninvasive alternatives have recently been suggested by several groups. Our group previously developed a functional sensor based on diffuse reflectance measurements with one UVB LED, which was previously evaluated on pig ear skin. Here we present the results of a systematic in vivo study using 12 sunscreens on 10 volunteers (skin types [ST] I-III). The relationship of the UVB-LED reflectance of unprotected skin and melanin index was determined for each ST. The spatial variation of the reflectance signal of different positions was analyzed and seems to be mainly influenced by sample inhomogeneity except for high-protection factors (PFs) where signal levels are close to detection noise. Despite the low-signal levels, a correlation of the measured LED-based UVB PF with SPF reference values from test institutes with R2 = 0.57 is obtained, suggesting a strong relationship of SPF and LED-based UVB-PF. Measured PFs tend to be lower for increasing skin pigmentation. The sensor design seems to be suitable for investigations where a fast measurement of relative changes of PFs, such as due to inhomogeneous application, bathing and sweating, is of interest.
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Affiliation(s)
- Susanna Kobylinski
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Berlin, Germany
| | - Carina Reble
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Berlin, Germany
- Courage + Khazaka electronic GmbH, Cologne, Germany
| | - Sabine Schanzer
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Berlin, Germany
| | - Ingo Gersonde
- University of Potsdam, Physical Chemistry - innoFSPEC, Potsdam-Golm, Germany
| | - Georg Wiora
- Courage + Khazaka electronic GmbH, Cologne, Germany
| | - Neysha Lobo Ploch
- Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Berlin, Germany
| | | | - Ludger Kolbe
- Beiersdorf AG, Research and Development, Hamburg, Germany
| | | | - Jürgen Lademann
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Berlin, Germany
| | - Martina C Meinke
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Dermatology, Venerology and Allergology, Berlin, Germany
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6
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Baswan SM, Marini A, Klosner AE, Jaenicke T, Leverett J, Murray M, Gellenbeck KW, Krutmann J. Orally administered mixed carotenoids protect human skin against ultraviolet A-induced skin pigmentation: A double-blind, placebo-controlled, randomized clinical trial. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2020; 36:219-225. [PMID: 32072695 DOI: 10.1111/phpp.12541] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 01/17/2020] [Accepted: 02/06/2020] [Indexed: 12/23/2022]
Abstract
BACKGROUND Photoprotection of human skin is determined as the capacity of sunscreens to prevent ultraviolet (UV) B radiation-induced erythema and UVA radiation-induced pigmentation. It is unequivocal that, in addition to sunscreens, oral supplementation with carotenoids can protect human skin against UVB radiation-induced erythema. It is not known if this is also the case for UVA radiation-induced pigmentation. OBJECTIVE To clinically evaluate the photoprotective effects of daily supplementation with carotenoids against UVA radiation-induced pigmentation. METHODS In this double-blind, placebo-controlled trial, 60 subjects (Fitzpatrick types II-IV) were randomized to receive Nutrilite™ Multi Carotene supplement or placebo for 12 weeks. UVB-induced minimal erythemal dose (MED), UVA-induced minimal persistent pigmentation dose (MPPD) and skin carotenoid levels were measured at baseline, 4, 8, and 12 weeks of intervention. Skin color was evaluated by expert clinical graders and by colorimetry. Carotenoid levels in the skin were measured by the Biozoom® device. RESULTS In the intervention group, a significant increase in comparison with the placebo group was observed in (a) skin carotenoid levels, (b) UVB-induced MED, and (c) UVA-induced MPPD values obtained by colorimetry. CONCLUSION Daily supplementation with carotenoids protects human skin against both UVB-induced erythema and UVA-induced pigmentation.
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Affiliation(s)
| | - Alessandra Marini
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Allison E Klosner
- Nutrilite Health Institute R&D, Amway Corporation, Buena Park, CA, USA
| | - Thomas Jaenicke
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | | | - Mary Murray
- Nutrilite Health Institute R&D, Amway Corporation, Buena Park, CA, USA
| | | | - Jean Krutmann
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
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7
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A Randomized Study to Determine the Sun Protection Factor of Natural Pterostilbene from Pterocarpus Marsupium. COSMETICS 2020. [DOI: 10.3390/cosmetics7010016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Ultraviolet (UV) rays and its harmful effects have always been a concern to skin health. Sunscreen and sunblock prevent the harmful effects of UV radiation on the skin. Sun Protection Factor (SPF) is an indication of the sun-protective capacity of an ingredient. There is an ever increasing interest in the cosmetic industry for developing novel functional ingredients from natural sources. The purpose of this study was to determine in-vitro and in vivo SPF of natural 90% pterostilbene extracted from the dried heartwood of Pterocarpus marsupium (Indian Kino). The SPF of purified pterostilbene and a formulation containing 0.4% pterostilbene was determined In Vitro using a UV spectrophotometer. Pterostilbene had an SPF of 21.73 ± 0.06, while the cream formulation had an SPF of 8.84 ± 0.01. The in vivo SPF of the 0.4% pterostilbene cream in humans was found to be 6.2 ± 1.30. Primary skin irritation tests in human subjects showed the formulation was safe and had no irritation potential. Pterostilbene was also found to have significant antioxidant activity as determined by free radical scavenging assays in vitro. These results suggest that natural pterostilbene is an antioxidant and shows SPF value both in-vitro and in the human clinical study and thus could be used as an ingredient in topical sun-protective formulations.
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8
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Tan Y, Wang F, Fan G, Zheng Y, Li B, Li N, Liu Y, Wang X, Liu W, Krutmann J, Zou Y, Wang S. Identification of factors associated with minimal erythema dose variations in a large-scale population study of 22 146 subjects. J Eur Acad Dermatol Venereol 2020; 34:1595-1600. [PMID: 31955464 PMCID: PMC7496195 DOI: 10.1111/jdv.16206] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 12/31/2019] [Indexed: 12/01/2022]
Abstract
Background Minimal erythema dose (MED) has substantial inter‐ and intraindividual variations, reflecting the influence of very diverse factors. However, related studies showed little consistency probably because of their limited sample size. Objective To identify the factors associated with MED variations in a large‐scale population study. Methods The MED test was performed by following the international standard procedure on 22 146 subjects. The results were analysed in adjusted multivariable linear and logistic regression models. Results This large‐scale study revealed that lower MED was consistently associated with lighter skin [β‐coefficient = −0.33, 95% confidence interval (CI) −0.36 to 0.30, P = 6.41 × 10−84]. Females had significantly higher MED than male (β = 0.91, 0.32–1.50, P = 2.93 × 10−3). Stratified analyses showed that MED was not associated with age [female: odds ratio (OR) = 0.99, 0.98–1.01; male: OR = 0.99, 0.97–1.00]. MED was lower in summer than in other seasons (spring: OR = 1.08, 1.06–1.11; autumn: OR = 1.11, 1.08–1.13; winter: OR = 1.20, 1.18–1.22). Furthermore, MED was associated with air temperature (β = −0.36, −0.49 to 0.23, P = 4.81 × 10−8) and air pressure (β = −0.64, −0.82 to 0.46, P = 8.01 × 10−12) in summer only while not in other seasons. Conclusions This study provides unprecedented evidence that MED is associated with skin colour, sex, season and meteorological factors, but not with age.
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Affiliation(s)
- Y Tan
- Department of Skin & Cosmetic Research, Shanghai Skin Disease Hospital, Shanghai, China.,Human Phenome Institute, Fudan University, Shanghai, China.,NMPA Key Laboratory for Monitoring and Evaluation of Cosmetics, Shanghai, China
| | - F Wang
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - G Fan
- Department of Skin & Cosmetic Research, Shanghai Skin Disease Hospital, Shanghai, China.,NMPA Key Laboratory for Monitoring and Evaluation of Cosmetics, Shanghai, China
| | - Y Zheng
- Human Phenome Institute, Fudan University, Shanghai, China
| | - B Li
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - N Li
- Department of Skin & Cosmetic Research, Shanghai Skin Disease Hospital, Shanghai, China
| | - Y Liu
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - X Wang
- Department of Skin & Cosmetic Research, Shanghai Skin Disease Hospital, Shanghai, China
| | - W Liu
- Department of Dermatology, Air Force General Hospital, Beijing, China
| | - J Krutmann
- Human Phenome Institute, Fudan University, Shanghai, China.,IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.,Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Y Zou
- Department of Skin & Cosmetic Research, Shanghai Skin Disease Hospital, Shanghai, China.,NMPA Key Laboratory for Monitoring and Evaluation of Cosmetics, Shanghai, China
| | - S Wang
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Shanghai, China
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9
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Krutmann J, Passeron T, Gilaberte Y, Granger C, Leone G, Narda M, Schalka S, Trullas C, Masson P, Lim HW. Photoprotection of the future: challenges and opportunities. J Eur Acad Dermatol Venereol 2020; 34:447-454. [PMID: 31898355 DOI: 10.1111/jdv.16030] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 10/17/2019] [Indexed: 12/21/2022]
Abstract
The use of sunscreens is an important and essential component of photoprotection. Since their introduction during the first half of the last century, sunscreens have benefited enormously from major technological advances such as the development of novel UV filters; as a result, their efficacy in preventing UV-induced erythema is unequivocal. More recently, however, new challenges have appeared, which have prompted a robust discussion about the safety of sunscreens. These include topics directly related to photoprotection of human skin such as improved/alternative methods for standardization of assessment of the efficacy of sunscreens, but also many others such as photoprotection beyond UV, concerns about human toxicity and ecological safety, the potential of oral photoprotective measures, consequences of innovative galenic formulations. On a first glance, some of these might raise questions and doubts among dermatologists, physicians and the general public about the use sunscreens as a means of photoprotection. This situation has prompted us to critically review such challenges, but also opportunities, based on existing scientific evidence. We conclude by providing our vision about how such challenges can be met best in the future in an attempt to create the ideal sunscreen, which should provide adequate and balanced protection and be easy and safe to use.
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Affiliation(s)
- J Krutmann
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany.,Medical Faculty, University of Düsseldorf, Düsseldorf, Germany
| | - T Passeron
- Department of Dermatology, Université Côte d'Azur. Centre Hospitalo-Universitaire de Nice, Nice, France.,Inserm U1065, C3M, Université Côte d'Azur, Nice, France
| | - Y Gilaberte
- Dermatology Department, IIS Aragon, Hospital Universitario Miguel Servet, Zaragoza, Spain.,University of Zaragoza, Zaragoza, Spain
| | - C Granger
- Innovation and Development, ISDIN, Barcelona, Spain
| | - G Leone
- San Gallicano Dermatological Institute IRCCS, Roma, Italy
| | - M Narda
- Innovation and Development, ISDIN, Barcelona, Spain
| | - S Schalka
- Medcin Skin Research Center, São Paulo, Brazil
| | - C Trullas
- Innovation and Development, ISDIN, Barcelona, Spain
| | - P Masson
- Phi Consulting, Bordeaux, France
| | - H W Lim
- Department of Dermatology, Henry Ford Hospital, Detroit, MI, USA
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10
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Hogue L, Harvey VM. Basal Cell Carcinoma, Squamous Cell Carcinoma, and Cutaneous Melanoma in Skin of Color Patients. Dermatol Clin 2019; 37:519-526. [PMID: 31466591 DOI: 10.1016/j.det.2019.05.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Skin cancers are relatively rare in patients with skin of color; however, they are an important public health concern because of disparities in patient outcomes. Gaps in skin cancer knowledge exist because of lack of large-scale studies involving people of color, and limitations in data collection methods and skin classification paradigms. Additional research is needed to address questions regarding risk and reasons for disparate skin cancer outcomes in these patients. We summarize the clinical and epidemiologic features for basal cell carcinoma, squamous cell carcinoma, and melanoma and touch on some of their unique features in patients with skin of color.
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Affiliation(s)
- Latrice Hogue
- Department of Dermatology, Wake Forest School of Medicine, Winston Salem, NC, USA
| | - Valerie M Harvey
- Hampton University Skin of Color Research Institute, Hampton, VA, USA; TPMG Hampton Roads Center for Dermatology, Newport News, VA, USA.
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11
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Trullàs C, Granger C, Lim HW, Krutmann J, Masson P. Linear and exponential sunscreen behaviours as an explanation for observed discrepancies in sun protection factor testing. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2019; 36:351-356. [PMID: 31376288 PMCID: PMC7540522 DOI: 10.1111/phpp.12500] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/08/2019] [Accepted: 07/24/2019] [Indexed: 11/28/2022]
Abstract
Background In vivo testing of sun protection factor (SPF) values can show considerable interlaboratory variability. We studied the underlying reasons and clinical implications. Methods Following the ISO 24444:2010 SPF testing method, seven contract research organizations (CROs) tested eight sunscreens marketed as SPF50 or SPF50+ and the reference SPF15 sunscreens P2 and P3 and SPF43 P6. We analysed differences in the products and CRO testing methods with regard to SPF variability. We tested the erythema prevention capacity of five of the products in subjects exposed to high doses of natural sunlight in Mauritius. Results Sun protection factor values varied dramatically between different CROs for some, but not all of the sunscreens. Those with the largest variability had an SPF50+, and their SPF values differed from a maximum of 62.4 to a minimum of 5.5. These products did not share a common sun‐filter composition, and some CROs used low and others high irradiation dose regimens. When comparing these two regimens, test products fell into two categories: (i) they either behaved similarly (“linear”) or (ii) they behaved differently (“exponential”). In the outdoor clinical study, exponential and linear sunscreens did not differ in their photoprotection capacities. Conclusion Differences in reported SPF values depend on the linear vs exponential behaviour of such products if subjected to low‐ vs high‐dose test regimens. Under real‐time exposure to natural sunlight, exponential and linear sunscreens did not differ in their erythema prevention capacity. Laboratory SPF testing of exponential sunscreens bears the risk of underestimating their in‐use SPF.
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Affiliation(s)
| | | | - Henry W Lim
- Department of Dermatology, Henry Ford Hospital, Detroit, MI, USA
| | - Jean Krutmann
- IUF - Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
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Suh H, Lewis J, Fong L, Ramseier JY, Carlson K, Peng Z, Yin ES, Saltzman WM, Girardi M. Biodegradable bioadhesive nanoparticle incorporation of broad-spectrum organic sunscreen agents. Bioeng Transl Med 2019; 4:129-140. [PMID: 30680324 PMCID: PMC6336670 DOI: 10.1002/btm2.10092] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 04/17/2018] [Accepted: 04/17/2018] [Indexed: 11/17/2022] Open
Abstract
Conventional emulsion-based sunscreen formulations are limited by postapplication epicutaneous penetration that increases the risk of allergic dermatitis, cellular damage, and filter photodegradation upon ultraviolet radiation (UVR) exposure. Encapsulation of the UVB filter padimate O within bioadhesive biodegradable nanoparticles (BNPs) composed of poly(d,l-lactic acid)-hyperbranched polyglycerol was previously shown to enhance UVR protection while preventing skin absorption. Herein, we assess the capacity of BNP co-incorporation of avobenzone and octocrylene to provide broad-spectrum UVR protection. The ratio of UV filters within nanoparticles (NPs) was optimized for filter-filter stabilization upon UV irradiation and maximum drug loading. In vitro water-resistance test showed significant particle retention at 85% over 3 hr. In a pilot clinical study, protection against UVR-induced erythema of BNPs was found to be comparable to the FDA standard P2. Thus, sunscreen formulations utilizing BNP incorporation of a combination of organic filters may offer key safety and performance advantages.
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Affiliation(s)
- Hee‐Won Suh
- Dept. of Biomedical Engineering, Yale School of Engineering & Applied Science55 Prospect Street, New HavenCT06520
| | - Julia Lewis
- Dept. of Dermatology, Yale School of Medicine333 Cedar Street, New HavenCT06520
| | - Linda Fong
- Dept. of Biomedical Engineering, Yale School of Engineering & Applied Science55 Prospect Street, New HavenCT06520
| | - Julie Ying Ramseier
- Dept. of Dermatology, Yale School of Medicine333 Cedar Street, New HavenCT06520
| | - Kacie Carlson
- Dept. of Dermatology, Yale School of Medicine333 Cedar Street, New HavenCT06520
| | - Zheng‐Hong Peng
- Dept. of Biomedical Engineering, Yale School of Engineering & Applied Science55 Prospect Street, New HavenCT06520
| | - Emily Sara Yin
- Dept. of Dermatology, Yale School of Medicine333 Cedar Street, New HavenCT06520
| | - W. Mark Saltzman
- Dept. of Biomedical Engineering, Yale School of Engineering & Applied Science55 Prospect Street, New HavenCT06520
| | - Michael Girardi
- Dept. of Dermatology, Yale School of Medicine333 Cedar Street, New HavenCT06520
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Rodriguez J, Maibach HI. Percutaneous penetration and pharmacodynamics: Wash-in and wash-off of sunscreen and insect repellent. J DERMATOL TREAT 2015; 27:11-8. [DOI: 10.3109/09546634.2015.1050350] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Agbai ON, Buster K, Sanchez M, Hernandez C, Kundu RV, Chiu M, Roberts WE, Draelos ZD, Bhushan R, Taylor SC, Lim HW. Skin cancer and photoprotection in people of color: a review and recommendations for physicians and the public. J Am Acad Dermatol 2014; 70:748-762. [PMID: 24485530 DOI: 10.1016/j.jaad.2013.11.038] [Citation(s) in RCA: 188] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Revised: 11/26/2013] [Accepted: 11/26/2013] [Indexed: 02/07/2023]
Abstract
Skin cancer is less prevalent in people of color than in the white population. However, when skin cancer occurs in non-whites, it often presents at a more advanced stage, and thus the prognosis is worse compared with white patients. The increased morbidity and mortality associated with skin cancer in patients of color compared with white patients may be because of the lack of awareness, diagnoses at a more advanced stage, and socioeconomic factors such as access to care barriers. Physician promotion of skin cancer prevention strategies for all patients, regardless of ethnic background and socioeconomic status, can lead to timely diagnosis and treatment. Public education campaigns should be expanded to target communities of color to promote self-skin examination and stress importance of photoprotection, avoidance of tanning bed use, and early skin cancer detection and treatment. These measures should result in reduction or earlier detection of cutaneous malignancies in all communities. Furthermore, promotion of photoprotection practices may reduce other adverse effects of ultraviolet exposure including photoaging and ultraviolet-related disorders of pigmentation.
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Affiliation(s)
- Oma N Agbai
- Multicultural Dermatology Center, Department of Dermatology, Henry Ford Hospital, Detroit, Michigan
| | - Kesha Buster
- Department of Dermatology, Via Christi Clinic, Wichita, Kansas
| | - Miguel Sanchez
- Department of Dermatology, New York University Medical Center, New York, New York
| | - Claudia Hernandez
- Department of Dermatology, University of Illinois College of Medicine, Chicago, Illinois
| | - Roopal V Kundu
- Northwestern Center for Ethnic Skin, Department of Dermatology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Melvin Chiu
- Division of Dermatology, University of California Los Angeles Medical Center, Los Angeles, California
| | | | - Zoe D Draelos
- Dermatology Consulting Services, High Point, North Carolina
| | - Reva Bhushan
- American Academy of Dermatology, Schaumburg, Illinois.
| | - Susan C Taylor
- Society Hill Dermatology and Cosmetic Center, Philadelphia, Pennsylvania
| | - Henry W Lim
- Multicultural Dermatology Center, Department of Dermatology, Henry Ford Hospital, Detroit, Michigan
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15
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Cole C. Sunscreens - what is the ideal testing model? PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2014; 30:81-7. [DOI: 10.1111/phpp.12095] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/03/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Curtis Cole
- Johnson & Johnson Consumer and Personal Products Co. Inc.; Skillman NJ USA
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Cooley JH, Quale LM. Skin Cancer Preventive Behavior and Sun Protection Recommendations. Semin Oncol Nurs 2013; 29:223-6. [DOI: 10.1016/j.soncn.2013.06.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Javeri A, Lyons JG, Huang XX, Halliday GM. Downregulation of Cockayne syndrome B protein reduces human 8-oxoguanine DNA glycosylase-1 expression and repair of UV radiation-induced 8-oxo-7,8-dihydro-2'-deoxyguanine. Cancer Sci 2011; 102:1651-8. [PMID: 21668583 PMCID: PMC11159239 DOI: 10.1111/j.1349-7006.2011.02005.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Human 8-oxoguanine DNA glycosylase-1 (hOGG1) is the key DNA repair enzyme responsible for initiating repair of UV radiation-induced 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG). Previously we have shown that basal cells in human epidermis are particularly sensitive to UVA-mediated DNA damage probably due to low expression of hOGG1. Here we investigate some aspects of the regulatory role of Cockayne syndrome B (CSB) on hOGG1 expression and function. Cockayne syndrome B and hOGG1 genes were knocked down by miRNA technology in the HaCaT human keratinocyte cell line. Loss of the CSB gene decreased hOGG1 mRNA, and loss of hOGG1 increased CSB, indicating that they influence each other's expression. Protein levels were assessed in cells grown into engineered human skin using immunohistochemistry. This confirmed that CSB knockdown with miRNA reduced hOGG1 protein levels, but hOGG1 knockdown did not influence expression of CSB protein. Using comet assay we found that both hOGG1 and CSB knockdown reduced repair of both UVA- and UVB-induced 8-oxo-dG, consistent with CSB downregulation of hOGG1 mRNA and protein. In contrast, CSB but not hOGG1 knockdown reduced repair of UVB- and UVA-induced cyclobutane pyrimidine dimer photolesions. In engineered human skin, repair of UVA-induced 8-oxo-dG was inhibited by both hOGG1 and CSB knockdown, confirming the functional role of both proteins in cells with 3-D cellular contacts. These findings directly indicate that hOGG1 and CSB influence each other's expression. CSB is required for maintaining hOGG1 enzyme levels and function. Cockayne syndrome B could therefore be required for 8-oxo-dG repair due to its regulatory effect on hOGG1 expression. Cockayne syndrome B but not hOGG1 is also required for efficient repair of cyclobutane pyrimidine dimers. Cockayne syndrome B regulation of DNA repair could contribute to the effect of UVA in causing mutations that lead to skin cancer in humans.
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Affiliation(s)
- Arash Javeri
- Discipline of Dermatology, Bosch Institute, Dermatology Research Laboratory, University of Sydney, Sydney, New South Wales, Australia
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Kim SM, Oh BH, Lee YW, Choe YB, Ahn KJ. The relation between the amount of sunscreen applied and the sun protection factor in Asian skin. J Am Acad Dermatol 2010; 62:218-22. [DOI: 10.1016/j.jaad.2009.06.047] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2009] [Revised: 06/01/2009] [Accepted: 06/10/2009] [Indexed: 11/25/2022]
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Moyal D, Wichrowski K, Tricaud C. In vivo persistent pigment darkening method: a demonstration of the reproducibility of the UVA protection factors results at several testing laboratories. PHOTODERMATOLOGY PHOTOIMMUNOLOGY & PHOTOMEDICINE 2006; 22:124-8. [PMID: 16719864 DOI: 10.1111/j.1600-0781.2006.00223.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND/PURPOSE The aims of the present studies were to check that persistent pigment darkening (PPD) method can produce accurate and reproducible results for high UVA protection factors (UVAPF) and to provide data on the variability between laboratories and on the influence of skin types. METHODS The Japanese Cosmetic Industry Association (JCIA) PPD method was used to determine the UVAPF in different laboratories of different sunscreen formulations with increasing UVAPF. Two formulations were tested at seven independent laboratories and five products within two laboratories. The influence of skin types on the UVAPF of two products was tested within one laboratory on two panels of volunteers. All laboratories complied with the JCIA method specifications. RESULTS Reproducible results have been obtained between the different labs and a low and satisfactory variability was achieved with a panel size of 10 subjects. Furthermore, skin type was demonstrated to have no influence within the defined selection criteria. CONCLUSIONS From this multiple center testing, the PPD method has been shown to be appropriate for testing sunscreen formulations with UVAPFs above 20. It is reasonable to expect that test results will be consistent if an identical protocol is used between laboratories.
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Maier T, Korting HC. Sunscreens – Which and What for? Skin Pharmacol Physiol 2005; 18:253-62. [PMID: 16113595 DOI: 10.1159/000087606] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2004] [Accepted: 05/13/2005] [Indexed: 12/13/2022]
Abstract
It is well established that sun exposure is the main cause for the development of skin cancer. Chronic continuous UV radiation is believed to induce malignant melanoma, whereas intermittent high-dose UV exposure contributes to the occurrence of actinic keratosis as precursor lesions of squamous cell carcinoma as well as basal cell carcinoma. Not only photocarcinogenesis but also the mechanisms of photoaging have recently become apparent. In this respect the use of sunscreens seemed to prove to be more and more important and popular within the last decades. However, there is still inconsistency about the usefulness of sunscreens. Several studies show that inadequate use and incomplete UV spectrum efficacy may compromise protection more than previously expected. The sunscreen market is crowded by numerous products. Inorganic sunscreens such as zinc oxide and titanium oxide have a wide spectral range of activity compared to most of the organic sunscreen products. It is not uncommon for organic sunscreens to cause photocontact allergy, but their cosmetic acceptability is still superior to the one given by inorganic sunscreens. Recently, modern galenic approaches such as micronization and encapsulation allow the development of high-quality inorganic sunscreens. The potential systemic toxicity of organic sunscreens has lately primarily been discussed controversially in public, and several studies show contradictory results. Although a matter of debate, at present the sun protection factor (SPF) is the most reliable information for the consumer as a measure of sunscreen filter efficacy. In this context additional tests have been introduced for the evaluation of not only the protective effect against erythema but also protection against UV-induced immunological and mutational effects. Recently, combinations of UV filters with agents active in DNA repair have been introduced in order to improve photoprotection. This article reviews the efficacy of sunscreens in the prevention of epithelial and nonepithelial skin cancer, the effect on immunosuppression and the value of the SPF as well as new developments on the sunscreen market.
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Affiliation(s)
- T Maier
- Department of Dermatology and Allergology, Ludwig Maximilian University, Munich, Germany.
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Costa FB, Weber MB. Avaliação dos hábitos de exposição ao sol e de fotoproteção dos universitários da Região Metropolitana de Porto Alegre, RS. An Bras Dermatol 2004. [DOI: 10.1590/s0365-05962004000200003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
FUNDAMENTOS: Sabe-se que a mudança de hábito da população mundial com relação à exposição ao sol provocou aumento da incidência de câncer da pele nas últimas décadas. Tais informações são especialmente relevantes na Região Sul, na qual há maior prevalência da população branca, mais propensa aos danos solares, em comparação ao restante do Brasil. OBJETIVOS: Avaliar os hábitos de exposição ao sol e de fotoproteção dos universitários da Região Metropolitana de Porto Alegre no período de julho a setembro de 2001. MÉTODOS: Foram respondidos 1.030 questionários por universitários residentes na Região Metropolitana de Porto Alegre. RESULTADOS: Nos finais de semana, 38,4% dos estudantes permanecem ao sol entre duas e seis horas diárias. Durante o verão, 43,7% deles se expõem ao sol entre as 10 e as 15h; 85% dos estudantes afirmam usar filtro solar, mas 65% não o usam ao praticar esportes ao ar livre. CONCLUSÕES: Os autores observaram que a maioria dos universitários se expõe excessivamente ao sol, em horários impróprios e sem efetiva proteção solar.
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Kuchel JM, Barnetson RSC, Halliday GM. Nitric oxide appears to be a mediator of solar-simulated ultraviolet radiation-induced immunosuppression in humans. J Invest Dermatol 2003; 121:587-93. [PMID: 12925219 DOI: 10.1046/j.1523-1747.2003.12415.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Topical application of NG-methyl-L-arginine and 2,2'-dipyridyl were used to examine the respective roles of nitric oxide and reactive oxygen species in solar-simulated ultraviolet radiation-induced immunosuppression in humans in vivo. Immunosuppression was studied using a nickel contact hypersensitivity recall model. Ultraviolet radiation dose-responses were generated to determine the extent to which NG-methyl-L-arginine and 2,2'-dipyridyl affected the immune response. NG-methyl-L-arginine but not 2,2'-dipyridyl protected the immune system from ultraviolet radiation-induced suppression. Both NG-methyl-L-arginine and 2,2'-dipyridyl inhibited nitrite production. Nitrite is a degradation product of peroxynitrite, a cytotoxic mediator resulting from reactions between nitric oxide and reactive oxygen species. This suggests that nitric oxide, not its downstream product peroxynitrite, was likely to be responsible for solar-simulated ultraviolet radiation-induced immunosuppression. In contrast, both nitric oxide and reactive oxygen species were mediators of solar-simulated ultraviolet radiation-induced apoptosis and loss of dendritic S-100+ cells (probably Langerhans cells) from the epidermis. It is likely that different mechanisms are involved in these ultraviolet-induced endpoints and that events in addition to Langerhans cell depletion are important for local immune suppression to recall antigens in humans. Understanding the mechanisms of cutaneous ultraviolet-induced oxidative stress will assist in the future design of novel products that protect skin from photoaging and skin cancer.
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Affiliation(s)
- Johanna M Kuchel
- Department of Medicine (Dermatology), The Melanoma and Skin Cancer Research Institute, Royal Prince Alfred Hospital at The University of Sydney, Sydney, NSW 2006, Australia
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Poon TSC, Barnetson RS. The importance of using broad spectrum SPF 30+ sunscreens in tropical and subtropical climates. PHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE 2002; 18:175-8. [PMID: 12390671 DOI: 10.1034/j.1600-0781.2002.00768.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND/PURPOSE To evaluate the Sun Protection Factors (SPF) of six sunscreens sold in Australia, using an ultraviolet (UV) spectrum which mimics sunlight as closely as possible, and by using volunteers with a range of skin types to reflect the Australian population. METHODS Open prospective study. Seventy-five volunteers of skin types 1-3 were tested in a dermatology research laboratory in a major metropolitan teaching hospital in Sydney, Australia in the years 2000-2001. Sunscreen SPF's were measured using a solar simulator and procedures which complied with the Australian Standard. RESULTS Sun Protection Factors, as measured by a solar simulator more approximating to natural sunlight than commercial simulators, and using individuals of skin type 1-3, were shown to be approximately between 50% and 80% of their labelled value. Sunscreen application method can also affect SPF measurement. CONCLUSION For a number of reasons, Sun Protection Factors are often overestimated. In addition, many individuals use less than half the amount of sunscreen recommended. Those living in tropical or subtropical climates should be encouraged to use only broad spectrum SPF 30+ sunscreens to achieve adequate protection from the sun.
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Affiliation(s)
- Terence S C Poon
- Department of Medicine (Dermatology), Melanoma and Skin Cancer Research Institute, Royal Prince Alfred Hospital at The University of Sydney, Camperdown NSW 2050, Australia
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