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.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

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

Urinary thymidine dimer excretion reflects personal ultraviolet radiation exposure levels

Exposure to ultraviolet radiation (UVR) leads to skin DNA damage, specifically in the form of cyclobutane pyrimidine dimers, with thymidine dimers being the most common. Quantifying these dimers can indicate the extent of DNA damage resulting from UVR exposure. Here, a new liquid chromatography-mass spectrometry (LC-MS) method was used to quantify thymidine dimers in the urine after a temporary increase in real-life UVR exposure. Healthy Danish volunteers (n = 27) experienced increased UVR exposure during a winter vacation. Individual exposure, assessed via personally worn electronic UVR dosimeters, revealed a mean exposure level of 32.9 standard erythema doses (SEDs) during the last week of vacation. Morning urine thymidine dimer concentrations were markedly elevated both 1 and 2 days post-vacation, and individual thymidine dimer levels correlated with UVR exposure during the last week of the vacation. The strongest correlation with erythema-weighted personal UVR exposure (Power model, r2 = 0.64, p < 0.001) was observed when both morning urine samples were combined to measure 48-h thymidine dimer excretion, whereas 24-h excretion based on a single sample provided a weaker correlation (Power model, r2 = 0.55, p < 0.001). Sex, age, and skin phototype had no significant effect on these correlations. For the first time, urinary thymidine dimer excretion was quantified by LC-MS to evaluate the effect of a temporary increase in personal UVR exposure in a real-life setting. The high sensitivity to elevated UVR exposure and correlation between urinary excretion and measured SED suggest that this approach may be used to quantify DNA damage and repair and to evaluate photoprevention strategies.

Integrated sun protection advice for the South African population

Exposure to solar ultraviolet radiation (UVR) is associated with several cutaneous adverse effects. However, to the best of our knowledge, in South Africa there are no formal guidelines on sun protection. A group of South African dermatologists and researchers convened over the course of 1 year to deliberate on integrated advice for sun protection among the multi-ethnic South African population. For people with light skin and those with genetic skin disorders (e.g., oculocutaneous albinism), sun protection was identified as critical to prevent sunburn, skin cancer, and photoaging. The evidence is less clear for people with medium and darker skin types, especially the latter, in whom melanin may confer a degree of protection against some parts of the solar spectrum. Recent studies have demonstrated that visible light can cause pigmentary changes in individuals with darker skin types in particular. Sun protection for people of all skin colors is beneficial to protect against photoaging and ocular damage. Herein sun protection advice is suggested for South Africans of all skin colors to reduce morbidity and mortality from sun exposure, particularly relating to skin cancer. Several knowledge gaps are identified as future research priorities.

Sunburn and sun protection during recreational outdoor sport in summer: Findings from the German general population aged 16-65 years

BACKGROUND

Sunburn can increase one's risk of developing skin cancer. We aimed to quantify the prevalence of sunburn during recreational outdoor sport (ROS) in summer, to explore the use of different sun protection measures, and to examine factors associated with sunburn during ROS using a population-based sample from Germany.

METHODS

For this cross-sectional study, 2081 individuals aged 16-65 years who reported being engaged in ROS in summer were surveyed via standardized telephone interviews in 2020 (National Cancer Aid Monitoring, NCAM).

RESULTS

Overall, 16.7% reported experiencing at least one sunburn during ROS in the past twelve months. Sunburn occurrence was negatively associated with the age of the participants (e.g. OR = 0.49 in 56-65 year-olds, p < .001), and positively associated with skin type I/II (OR = 1.55, p < .001) and with having a higher number of nevi (OR = 1.42, p = .005). While wearing sleeved shirts was the most frequently-used sun protection measure during ROS (74.9%), wearing headgear was least common in our sample (29.0%). In multivariate analyses, sunburn was positively associated with the use of sun protection measures (e.g. OR = 1.32 for wearing sleeved shirts, p = .02).

CONCLUSIONS

Our nationwide data show that ROS is one of the settings where sun protection should play a greater role. Especially in organized sports, particular attention should be devoted to organizational (e.g. exercise outside peak hours) or contextual measures (e.g. shade by the natural or built environment) to prevent skin cancer in later life.

Nuclear and Urinary Measurements Show the Efficacy of Sun-Protection Factor 50+ Sunscreen against DNA Photoproducts upon Real-Life Recreational Exposure

Sunscreens have been shown to protect against UVR-induced DNA damage in human skin under laboratory conditions. We presently extended these observations to real-life conditions in volunteers after their ordinary exposure habits during summer holidays. Volunteers were randomly assigned to a control group and an educated group supplied with a SPF ≥50 sunscreen and receiving instructions for use. A questionnaire was used to determine the extent of exposure. No difference in average solar UVR exposure was found between the two groups. DNA photoprotection was first assessed by, to our knowledge, a previously unreported noninvasive assay on the basis of the quantification of pyrimidine dimers released by DNA repair in urine. Damage was also quantified in the nuclear DNA extracted from the roof of suction blisters collected after recreational exposure. The urinary concentration of photoproducts was significantly higher in the control than in the educated group. The same trend was observed for the level of photoproducts in the DNA from suction blisters. The unambiguous observation of an efficient photoprotection against DNA damage afforded by sunscreen under real-life conditions provides strong support for the efficiency of the sunscreens. In addition, the results validate the use of urinary DNA photoproducts as a noninvasive assay applicable to photoprotection.

The adverse consequences of not using sunscreens

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

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

BACKGROUND

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Dermatology Patients' Knowledge of Sunscreen Guidelines at a University Hospital in Saudi Arabia

Objective

The goal of this study is to assess the knowledge and attitude of dermatology patients regarding sunscreen use as recommended by the American Academy of Dermatology.

Methods

This was an observational cross-sectional study at a university hospital in Riyadh. Participants were asked to complete a questionnaire to measure their knowledge and attitude regarding sunscreen use. Results were analyzed using a chi-square test.

Results

Most participants heard about sunscreen (93.4%) and had indicated previous sunscreen use (72%). Sunscreen use was higher among women and participants with a postgraduate education. Sunscreen knowledge was higher among women, participants with non-photosensitive disorders, and participants with Fitzpatrick I, II, and III skin types. A total of 80% knew the worst time for sun exposure, but only 20.5% of the participants knew that sunscreen should be applied daily throughout the year, and 13.5% knew the correct minimum recommended SPF. A total of 34% were aware of the minimum time allowed for sunscreen application before sun exposure, and 20% were aware of the longest period allowed between reapplications. Only 4.5% knew the proper amount of sunscreen to cover the entire body.

Conclusion

Our study revealed that most participants had heard of sunscreen, however their knowledge of the guidelines for sunscreen use was poor. Only 33% of the participants had received a recommendation for using sunscreen from their general practitioner or dermatologist. More comprehensive and directed efforts need to be made in counselling and educating these patients on proper sunscreen practice.

Correlation of skin cancer and actinic keratosis-related knowledge and sun protection behaviors and sunscreen use among a sample of Jordanian population

BACKGROUND

The incidence of skin cancer and actinic keratosis has increased worldwide. Measuring the public awareness, attitude, and knowledge about these diseases and the skin protection behaviors are highly important to undertake preventive measures.

METHODS

To investigate skin cancer and actinic keratosis-related knowledge, sun protection behaviors, and sunscreen usage among Jordanians, a questionnaire was developed. The questionnaire was provided as a google form to individuals via social media and the data were analyzed using SPSS^® 23.

RESULTS

A total of 1277 individuals, aged 18-65 years filled the questionnaire. The median melanoma and actinic keratosis knowledge score were 7 (4-9) and 4 (0-9), respectively. The melanoma knowledge was higher among females, those with a medical background, a high level of education, and in the central region, whereas the AK knowledge was higher among those with a medical background. Overall, 75.9% of the participants used sunscreen at least often to prevent sunburn, uneven skin tone, or tanning, 72% were using sunscreen with an SPF of 30 at least. However, 45.3% and 49.2% of sunscreen users did not comply with application, and reapplication times, respectively. Moreover, 58.4% of participants applied less than the recommended amount of sunscreen.

CONCLUSION

Our study revealed that public awareness of actinic keratosis is low among Jordanians. Although it was found that a high proportion of Jordanians use sunscreens there are deficits in sunscreen practice indicating an urgent need to design effective interventions to increase awareness of actinic keratosis and correct use of sunscreen via health campaigns or healthcare professions.

The effect of on-site application density on the UV protection efficacy of sunscreens

BACKGROUND

Sun protection factor (SPF) and UVA protection factor (UVAPF) are performance indicators consumers recognize for UV protective cosmetics such as sunscreens. However, on-site application density affects actual UV protection, despite these indicators. To understand actual UV protection better, a more reliable manner is needed to verify application density for further discussion of photoprotection efficacy regarding public health.

OBJECTIVES

To estimate the UV protective efficacy of sunscreen in actual use based on the application density of UV protective cosmetics and the analysis of UV protective effect modulated by application density.

METHOD

The subjects applied the SPF-labeled sunscreens as usual. We measured the application amount and area including any amount on their hands to calculate the average application density on the face. Also, sunscreens were applied at densities of 0.5, 1.0, and 2.0 mg/cm² . The SPF values were measured at each application site to evaluate the effect of application density on photoprotection efficacy.

RESULT

We established a method of measuring application density utilizing three-dimensional photograph analysis. The median application density of the sunscreen applied in actual use was 1.33 mg/cm² . The measured SPF values decreased in association with the decreased application density of sunscreens. Based on the estimate assuming the first-order correlation, the SPF value required to get the protective effect equivalent to a sunscreen with SPF 15, 30, or 50 at 2 mg/cm² was calculated to be 23.8, 47.5, and 79.2, respectively, with the application density of 1.33 mg/cm² .

CONCLUSION

We demonstrated a reasonable procedure for estimating the photoprotection efficacy of sunscreens on the face. A suggestion was made to consider the application density for further discussion of photoprotection among consumers, especially for the long term with respect to public health.

An Exploration of the Use and Impact of Preventive Measures on Skin Cancer

Background: Skin cancer is the most common form of cancer, and both clinical and epidemiological data link cumulative solar dosages and the number of sunburns to skin cancer. Each year, more than 5.4 million new cases of skin cancer are diagnosed, incurring a significant health and financial burden. Recommended preventive measures for skin cancer include the use of sunscreen, sun avoidance, and protective clothing. This study used a national database to examine the association of preventive measures with the prevalence of skin cancer, specifically analyzing the preventive measures of sunscreen use, staying in the shade, and wearing long-sleeved shirts. The second aim was to determine which characteristics, if any, correlated with using prevention measures. Methods: This study analyzed data from the National Health and Nutritional Examination Survey 2015−2016 cycle to examine the association of three preventive measures (using sunscreen, staying in the shade, and wearing long-sleeved shirts) with skin cancer. Logistic regression and chi-square tests were utilized to examine the relationship between skin cancer and these prevention methods. Results: Sunscreen use (OR = 3.752; p < 0.05) was statistically associated with a lower prevalence of skin cancer, while wearing long-sleeved shirts (OR = 6.911; p = 0.064) and staying in the shade (OR = 0.646; p = 0.481) did not emerge as factors significantly associated with a lower prevalence after controlling for gender, race/ethnicity, marital status, income, health insurance, and general health. Additionally, men and individuals of color were less likely to use sunscreen. Conclusion: Sunscreen use was associated with a lower prevalence of skin cancer, while wearing long-sleeved shirts and staying in the shade was not significantly linked to lower rates of skin cancer, suggesting that these measures may not be as effective as sunscreen for preventing skin cancer. Men and individuals of color were significantly less likely to use sunscreen. These findings can help guide future education efforts and research regarding skin cancer prevention and suggest the need to develop male-oriented programs to mitigate the gender disparity in employing sun-protection measures.

Potential UV-Protective Effect of Freestanding Biodegradable Nanosheet-Based Sunscreen Preparations in XPA-Deficient Mice

Xeroderma pigmentosum (XP) is a rare autosomal recessive hereditary disorder. As patients with XP are deficient in nucleotide excision repair, they show severe photosensitivity symptoms. Although skin protection from ultraviolet (UV) radiation is essential to improve the life expectancy of such patients, the optimal protective effect is not achieved even with sunscreen application, owing to the low usability of the preparations. Nanosheets are two-dimensional nanostructures with a thickness in the nanometer range. The extremely large aspect ratios of the nanosheets result in high transparency, flexibility, and adhesiveness. Moreover, their high moisture permeability enables their application to any area of the skin for a long time. We fabricated preparations containing avobenzone (BMDBM) based on freestanding poly (L-lactic acid) (PLLA) nanosheets through a spin-coating process. Although monolayered PLLA nanosheets did not contain enough BMDBM to protect against UV radiation, the layered nanosheets, consisting of five discrete BMDBM nanosheets, showed high UV absorbance without lowering the adhesive strength against skin. Inflammatory reactions in XPA-deficient mice after UV radiation were completely suppressed by the application of BMDBM-layered nanosheets to the skin. Thus, the BMDBM layered nanosheet could serve as a potential sunscreen preparation to improve the quality of life of patients with XP.

A Randomized Double-blind Placebo-controlled Trial of Oral Aspirin for Protection of Melanocytic Nevi Against UV-induced DNA Damage

DNA damage plays a role in ultraviolet (UV)-induced melanoma. We previously showed that aspirin (ASA) can suppress prostaglandin-E2 (PGE2) and protect melanocytes from UV-induced DNA damage in mice, and suggested that taking ASA before acute sun exposure may reduce melanoma risk. We conducted a prospective randomized placebo-controlled trial to determine if orally administered ASA could suppress PGE2 in plasma and nevi and protect nevi from UV-induced DNA damage. After obtaining plasma and determining the minimal erythemal dose (MED) in 95 subjects at increased risk for melanoma, they were randomized to receive a daily dose of placebo, 81 mg ASA, or 325 mg ASA, in double-blind fashion for one month. After this intervention, one nevus was irradiated (dose = 1 or 2 MED) using a solar simulator. One day later, MED was re-determined, a second plasma sample was obtained, and the UV-irradiated nevus and an unirradiated nevus were removed. ASA metabolites were detected in the second plasma sample in subjects in the ASA arms. There were no significant differences in the pre- and post-intervention MED between those patients receiving ASA and placebo. Significantly reduced PGE2 levels were detected in plasma (second vs. first samples) and in nevi (both unirradiated and UV-treated) in subjects receiving ASA compared to placebo. Comparing UV-treated nevi from the ASA and placebo cohorts, however, did not reveal significant reductions in CD3-cell infiltration or 8-oxoguanine and cyclobutane pyrimidine dimers. Thus ASA did not effectively protect nevi from solar-simulated UV-induced inflammation and DNA damage under the conditions examined. PREVENTION RELEVANCE: Despite promising rationale, ASA at conventional dosing was not able to protect nevi against UV-induced DNA damage under the conditions examined.See related Spotlight, p. 71.

A new visible light absorbing organic filter offers superior protection against pigmentation by wavelengths at the UVR-visible boundary region

Skin pigmentation by solar ultraviolet radiation (UVR; ~295-400 nm) is well established. More recently, visible light (VL; 400-740 nm) has been shown to induce rapid pigmentation. Such pigmentation is thought to be caused by oxidative stress, which has associations with skin cancer and photoageing. However, the UVR-VL boundary region has been less well studied. The lower back of healthy Fitzpatrick skin type II-IV individuals was irradiated with increasing doses of narrow-band 385 nm and 405 nm radiation. Pigmentation change was measured immediately, 6 h and 24 h post-irradiation using two reflectance spectroscopy devices and visual grading. Pigmentation was dose-dependently increased in all skin types and time points for both spectra. Two sunscreens, both labelled SPF 15 and UVA protective in the EU and USA (but with different Boots star rating in the UK, 2* vs 5*) were compared. Their formulations were the same apart from the addition of a new organic filter bis-(diethylaminohydroxybenzoyl benzoyl) piperazine (BDBP) that absorbs between 350 and 425 nm. The product that lacked BDBP provided minimal protection against pigmentation, but its addition provided almost complete protection. This demonstrates the needs to improve photoprotection at the UVR-visible border and for sunscreens to act as neutral density filters.

Towards a paradigm shift in environmental health decision-making: a case study of oxybenzone

BACKGROUND

Technological advancements make lives safer and more convenient. Unfortunately, many of these advances come with costs to susceptible individuals and public health, the environment, and other species and ecosystems. Synthetic chemicals in consumer products represent a quintessential example of the complexity of both the benefits and burdens of modern living. How we navigate this complexity is a matter of a society's values and corresponding principles.

OBJECTIVES

We aimed to develop a series of ethical principles to guide decision-making within the landscape of environmental health, and then apply these principles to a specific environmental chemical, oxybenzone. Oxybenzone is a widely used ultraviolet (UV) filter added to personal care products and other consumer goods to prevent UV damage, but potentially poses harm to humans, wildlife, and ecosystems. It provides an excellent example of a chemical that is widely used for the alleged purpose of protecting human health and product safety, but with costs to human health and the environment that are often ignored by stakeholders.

DISCUSSION

We propose six ethical principles to guide environmental health decision-making: principles of sustainability, beneficence, non-maleficence, justice, community, and precautionary substitution. We apply these principles to the case of oxybenzone to demonstrate the complex but imperative decision-making required if we are to address the limits of the biosphere's regenerative rates. We conclude that both ethical and practical considerations should be included in decisions about the commercial, pervasive application of synthetic compounds and that the current flawed practice of cost-benefit analysis be recognized for what it is: a technocratic approach to support corporate interests.

Ultraviolet exposure to the face in patients with xeroderma pigmentosum and healthy controls: applying a novel methodology to define photoprotection behaviour

BACKGROUND

In Xeroderma Pigmentosum (XP), the main means of preventing skin and eye cancers is extreme protection against ultraviolet radiation (UVR). Protection is most important for the face.

OBJECTIVES

We aimed to assess how well patients with XP adhere to medical advice to protect against UVR by objectively estimating the mean daily dose of UVR to the face.

METHODS

We objectively estimated the UVR dose to the face in 36 XP patients and 25 healthy individuals over 3 weeks in the summer. We used a new methodology which combined UVR dose measurements from a wrist-worn dosimeter with an activity diary record of face photoprotection behaviour for each 15 minute period spent outside. A protection factor was associated with each behaviour, and the data analysed using a negative binomial mixed-effects model.

RESULTS

The mean daily UVR dose (weighted for DNA damage capacity) to the face in the XP patients was 0.13 Standard Erythemal Doses (SED) (mean in healthy individuals = 0.51 SED). There was wide variation between patients (range <0.01 - 0.48 SED/day). Self-caring adult patients had a very similar UV dose to the face to cared-for patients (0.13 vs 0.12 SED/day) despite photoprotecting much more poorly when outside, because the self-caring adults were outside in daylight much less.

CONCLUSIONS

Photoprotection behaviour varies widely within the XP group indicating that non-adherence to photoprotection advice is a significant issue. Timing and duration of going outside are as important as photoprotective measures taken when outside, to determine the UVR exposure to the face. This new methodology will be of value in identifying the sources of UVR exposure in other conditions where facial UV exposure is a key outcome, particularly in patients with multiple non-melanoma skin cancers.

Physical Determinants of Vitamin D Photosynthesis: A Review

Vitamin D synthesis by exposure of skin to solar ultraviolet radiation (UVR) provides the majority of this hormone that is essential for bone development and maintenance but may be important for many other health outcomes. This process, which is the only well-established benefit of solar UVR exposure, depends on many factors including genetics, age, health, and behavior. However, the most important factor is the quantity and quality of UVR reaching the skin. Vitamin D synthesis specifically requires ultraviolet B (UVB) radiation that is the minority component (<5%) of solar UVR. This waveband is also the most important for the adverse effects of solar exposure. The most obvious of which is sunburn (erythema), but UVB is also the main cause of DNA damage to the skin that is a prerequisite for most skin cancers. UVB at the Earth's surface depends on many physical and temporal factors such as latitude, altitude, season, and weather. Personal, cultural, and behavioral factors are also important. These include skin melanin, clothing, body surface area exposed, holiday habits, and sunscreen use. There is considerable disagreement in the literature about the role of some of these factors, possibly because some studies have been done by researchers with little understanding of photobiology. It can be argued that vitamin D supplementation obviates the need for solar exposure, but many studies have shown little benefit from this approach for a wide range of health outcomes. There is also increasing evidence that such exposure offers health benefits independently of vitamin D: the most important of which is blood-pressure reduction. In any case, public health advice must optimize risk versus benefit for solar exposure. It is fortunate that the individual UVB doses necessary for maintaining optimal vitamin D status are lower than those for sunburn, irrespective of skin melanin. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Novel sunprotection interventions to prevent skin cancer: A randomized study targeting Danes going on vacation to destinations with high UV index

Background

In Denmark, 16,500 cases of melanoma and keratinocyte cancers were registered in 2015, of which 90% could have been avoided by behavioral changes. We aimed to test novel interventions in a randomized design. The interventions targeted Danes going on vacation to high UVI destinations aiming to decrease sunburn by increasing use of sun protection to prevent skin cancer in the Danish population.

Methods

We report a randomized behavioral intervention during May-Dec 2018 with 1548 Danish adults on vacation in 2018 for a period of 1–3 weeks. The study population was population-based and aged 18–65 years. We tested two protection routines against minimal intervention control group (2-by2-factorial design): 1) Avoidance of the sun during peak hours and shade, use of the UV-index and planning of indoor/outdoor activity respectively and, 2) Coverage by increasing use of the hat advice and increasing sunscreen amount by application routine. Outcome was use of protection and sunburn.

Results

There were no differences in sunburn prevalence between intervention and control groups. Protection routine 1 and 2 both increased the overall protection score compared to non-users. Protection routine 1 increased the reported use of shade and decreased time exposed in the sun. Protection routine 2 increased the use of hat and sunscreen amount.

Conclusion

Simple measures can help avoid the majority of one of the most widespread cancers worldwide. Vacations to high UVI destinations is a major influence on the annual Danish UV-exposure. We influenced travelers to protect themselves better and to increase sun protection behavior.

Sunscreen application technique amongst patients with a history of skin cancer

BACKGROUND

Data on how patients with a history of skin cancer apply sunscreen are lacking.

OBJECTIVE

To characterize (1) gender differences in sunscreen application technique (quantity used, anatomic site coverage, and time allocated) and (2) differences in sunscreen application to unaffected skin versus previous skin cancer sites.

METHODS

Subjects with a history of skin cancer were asked to apply sunscreen to their head as they normally would. The amount of sunscreen used and application time were recorded. Before and after photos were taken. Using Wood's lamp lighting, an anatomic site coverage score was rated on an ordinal scale (1 = 0-25%, 2 = 26-50%, 3 = 51-75%, 4 = 76-100% coverage).

RESULTS

Males used 530 mg more sunscreen (p < 0.001) and applied approximately 5 mg/cm² of sunscreen versus women, who applied 2 mg/cm². The average coverage score was 3.27. Males were 7.61 times more likely to adequately apply sunscreen to the ears (p = 0.001). No differences were noted in application times. Coverage scores were similar for unaffected skin and previous skin cancer sites.

LIMITATIONS

Observations in a controlled setting may not reflect usual sunscreen application practices.

CONCLUSIONS

Overall, skin cancer survivors of both genders effectively applied sunscreen in line with recommended quantity guidelines, but men were significantly better at protecting their ears.

Consensus statement from 2nd International Conference on Controversies in Vitamin D

The 2nd International Conference on Controversies in Vitamin D was held in Monteriggioni (Siena), Italy, September 11-14, 2018. The aim of this meeting was to address ongoing controversies and timely topics in vitamin D research, to review available data related to these topics and controversies, to promote discussion to help resolve lingering issues and ultimately to suggest a research agenda to clarify areas of uncertainty. Several issues from the first conference, held in 2017, were revisited, such as assays used to determine serum 25-hydroxyvitamin D [25(OH)D] concentration, which remains a critical and controversial issue for defining vitamin D status. Definitions of vitamin D nutritional status (i.e. sufficiency, insufficiency and deficiency) were also revisited. New areas were reviewed, including vitamin D threshold values and how they should be defined in the context of specific diseases, sources of vitamin D and risk factors associated with vitamin D deficiency. Non-skeletal aspects related to vitamin D were also discussed, including the reproductive system, neurology, chronic kidney disease and falls. The therapeutic role of vitamin D and findings from recent clinical trials were also addressed. The topics were considered by 3 focus groups and divided into three main areas: 1) "Laboratory": assays and threshold values to define vitamin D status; 2) "Clinical": sources of vitamin D and risk factors and role of vitamin D in non-skeletal disease and 3) "Therapeutics": controversial issues on observational studies and recent randomized controlled trials. In this report, we present a summary of our findings.

Health Beliefs About UV and Skin Cancer Risk Behaviors

Our purpose was to examine the beliefs of college students about UV exposure and sunscreen use and their associations with skin cancer risk and protective behaviors in a cloudy climate. The sample was online survey participants (N = 334) recruited from a large university in Oregon. After fitting an initial measurement model, we fit a structural equation model including Health Beliefs About UV (HBAU) subscales (Health Benefits of Tanning, Seasonal Effects, Tanning Through the Winter, and Sunscreen Toxicity), outcome variables (sunscreen use, indoor tanning, and outdoor tanning), and covariates (eg, tanning and sunscreen use). A minority of participants held the beliefs represented by 3 HBAU subscales, but beliefs about negative health effects of the local weather (Tanning Through the Winter) were common. The measurement and adjusted models provided good fit to the data (χ2 = 143.30; P = .29; df = 136; Root-Mean Square Error of Approximation = .014; Comparative Fit Index = .992; Tucker-Lewis Index = .981). After adjusting for covariates, Sunscreen Toxicity predicted reduced sunscreen use (β = -.12, P = .021), Health Benefits of Tanning predicted outdoor tanning (β = .43, P < .001), and Tanning Through the Winter predicted indoor tanning (β = .31, P = .02). The small sample size, nonresponse rate, and cross-sectional nature of this study mean these findings should be interpreted cautiously. Beliefs about health benefits of sun exposure, the regional weather, and sunscreen safety play a role in skin cancer risk and protective behaviors.

Does sunscreen use comply with official recommendations? Results of a nationwide survey in Germany

BACKGROUND

The use of sunscreen can reduce the risk of UV-induced skin lesions. Health authorities have provided recommendations for the correct use of sunscreen use: Sufficient amount of sunscreen should be applied at least 30 min before the sun exposure and should be reapplied every 2 h.

OBJECTIVE

We aimed to research the practice of sunscreen use in a population-based and representative sample in Germany.

METHODS

For this cross-sectional survey, 3000 German residents aged 14-45 years were surveyed in standardized telephone interviews in 2018. Survey participants provided data on the frequency of sunscreen use in summer, timing of (re-)application and their skin characteristics. The data were weighted by age, sex, educational level and federal state to ensure the national representativeness of the sample.

RESULTS

Overall, 79.4% of respondents used sunscreen always, often or sometimes when being exposed to the sun. However, 87.2% of sunscreen users did not follow the recommendations on timing of application, 59.5% did not comply with the timing of reapplication. We also saw, that people potentially used too little sunscreen. These data did not differ noticeably by skin types of participants.

CONCLUSION

Our study revealed deficits in use of sunscreen in Germany, indicating that people here pay little attention to the recommendations of health authorities, regardless of their skin type. There is therefore an urgent need for targeted public information on this issue. Improving public knowledge on correct sunscreen use through educational campaigns or individual counselling by health professionals could be a first step.

Unintended sunburn after sunscreen application: An exploratory study of sun protection

ISSUE ADDRESSED

This study explores the experiences of adults aged 18 years and older who received an unintended sunburn while wearing sunscreen and examines why the application of sunscreen as a sun protection measure did not work as intended.

METHODS

Qualitative content analysis was conducted on 11 interviews with people living in Australia who had received an unintended sunburn. Data were collected from July 2017 to January 2018. Twelve participants took part in individual semi-structured interviews either face-to-face or over the telephone, and 11 participants met the eligibility criteria and were included for analysis.

RESULTS

The themes that emerged included experience of disbelief after sunburn; sunburn after water-based activity; inaccurate sunscreen application; sunscreen acceptability and trust; discomfort in application, opportunistic sun exposure; aesthetically motivated behaviour; normative beliefs; and lack of awareness of recent sun safety campaigns.

CONCLUSION

Participants perceived themselves as well protected from sun exposure and were surprised they received a sunburn. We found that participants did not reapply sunscreen often enough, especially before and during water activities and overestimated the amount of time they could be safely exposed to the sun. SO WHAT?: The findings of this study suggest a greater need for sun protection education on how to effectively use and apply sunscreen to avoid sunburn and skin cancer.

SUMMARY

This study explores the experiences of adults aged 18 years and older who received an unintended sunburn while wearing sunscreen and examines why the application of sunscreen as a sun protection measure did not work as intended. Qualitative content analysis was conducted on 11 interviews with people living in Australia who had received an unintended sunburn.

Suboptimal UVA attenuation by broad spectrum sunscreens under outdoor solar conditions contributes to lifetime UVA burden

BACKGROUND

Broad spectrum sunscreens with a sun protection factor (SPF) of 15 or greater are indicated to decrease the risk of skin cancer and early skin aging caused by the sun if used as directed with other sun protection measures. To determine whether sunscreen product performance is compromised under solar exposure and to test spectral uniformity of protection across the UVA spectrum, we tested broad spectrum sunscreens with a variety of active pharmaceutical ingredients (APIs) and in a variety of dosage forms.

METHODS

A cross-sectional market survey of 32 sunscreen drug products containing either organic or inorganic APIs with SPFs of 15, 30, 50, and 70 was tested. UV doses were delivered via natural sun in Silver Spring, Maryland between June and September of 2017.

RESULTS

Of the 32 sunscreen drug products, 6 products failed to meet their broad spectrum claim under solar exposure. Using FDA's new proposal to strengthen sunscreen broad spectrum requirements, spectral uniformity based on the mean sunscreen absorbance of UVA1(340-400 nm)/UV (290-400 nm) indicated that ~40% of sunscreen drug products tested had suboptimal UVA protection.

CONCLUSION

US consumers may unknowingly be receiving up to 36% more transmitted UVA when selecting between similarly labeled broad spectrum sunscreen drug products with equivalent SPF values. FDA's new proposal may help decrease consumers' overall lifetime UVA burden. Spectral absorbance data on sunscreen performance can be used to further improve the coupling of broad spectrum protection to a product's SPF value so that consumers have improved proportional increases in UV protection.

Sunscreen photoprotection and vitamin D status

Background

Global concern about vitamin D deficiency has fuelled debates on photoprotection and the importance of solar exposure to meet vitamin D requirements.

Objectives

To review the published evidence to reach a consensus on the influence of photoprotection by sunscreens on vitamin D status, considering other relevant factors.

Methods

An international panel of 13 experts in endocrinology, dermatology, photobiology, epidemiology and biological anthropology reviewed the literature prior to a 1‐day meeting in June 2017, during which the evidence was discussed. Methods of assessment and determining factors of vitamin D status, and public health perspectives were examined and consequences of sun exposure and the effects of photoprotection were assessed.

Results

A serum level of ≥ 50 nmol L⁻¹ 25(OH)D is a target for all individuals. Broad‐spectrum sunscreens that prevent erythema are unlikely to compromise vitamin D status in healthy populations. Vitamin D screening should be restricted to those at risk of hypovitaminosis, such as patients with photosensitivity disorders, who require rigorous photoprotection. Screening and supplementation are advised for this group.

Conclusions

Sunscreen use for daily and recreational photoprotection does not compromise vitamin D synthesis, even when applied under optimal conditions.

What's already known about this topic?

Knowledge of the relationship between solar exposure behaviour, sunscreen use and vitamin D is important for public health but there is confusion about optimal vitamin D status and the safest way to achieve this.

Practical recommendations on the potential impact of daily and/or recreational sunscreens on vitamin D status are lacking for healthy people.

What does this study add?

Judicious use of daily broad‐spectrum sunscreens with high ultraviolet (UV) A protection will not compromise vitamin D status in healthy people.

However, photoprotection strategies for patients with photosensitivity disorders that include high sun‐protection factor sunscreens with high UVA protection, along with protective clothing and shade‐seeking behaviour are likely to compromise vitamin D status.

Screening for vitamin D status and supplementation are recommended in patients with photosensitivity disorders.

Linked Comment: https://doi.org/10.1111/bjd.18126.

https://doi.org/10.1111/bjd.18494 available online

Optimal sunscreen use, during a sun holiday with a very high ultraviolet index, allows vitamin D synthesis without sunburn

Background

Sunlight contains ultraviolet (UV)A and UVB radiation. UVB is essential for vitamin D synthesis but is the main cause of sunburn and skin cancer. Sunscreen use is advocated to reduce the sun's adverse effects but may compromise vitamin D status.

Objectives

To assess the ability of two intervention sunscreens to inhibit vitamin D synthesis during a week‐long sun holiday.

Methods

The impact of sunscreens on vitamin D status was studied during a 1‐week sun holiday in Tenerife (28° N). Comparisons were made between two formulations, each with a sun protection factor (SPF) of 15. The UVA‐protection factor (PF) was low in one case and high in the other. Healthy Polish volunteers (n = 20 per group) were given the sunscreens and advised on the correct application. Comparisons were also made with discretionary sunscreen use (n = 22) and nonholiday groups (51·8° N, n = 17). Sunscreen use in the intervention groups was measured. Behaviour, UV radiation exposure, clothing cover and sunburn were monitored. Serum 25‐hydroxyvitamin D₃ [25(OH)D₃] was assessed by high‐performance liquid chromatography–tandem mass spectrometry.

Results

Use of intervention sunscreens was the same (P = 0·60), and both equally inhibited sunburn, which was present in the discretionary use group. There was an increase (P < 0·001) in mean ± SD 25(OH)D₃ (28·0 ± 16·5 nmol L⁻¹) in the discretionary use group. The high and low UVA‐PF sunscreen groups showed statistically significant increases (P < 0·001) of 19·0 ± 14·2 and 13·0 ± 11·4 nmol L⁻¹ 25(OH)D₃, respectively with P = 0·022 for difference between the intervention sunscreens. The nonholiday group showed a fall (P = 0·08) of 2·5 ± 5·6 nmol L⁻¹ 25(OH)D₃.

Conclusions

Sunscreens may be used to prevent sunburn yet allow vitamin D synthesis. A high UVA‐PF sunscreen enables significantly higher vitamin D synthesis than a low UVA‐PF sunscreen because the former, by default, transmits more UVB than the latter.

What's already known about this topic?

Action spectra (wavelength dependence) for erythema and the cutaneous formation of vitamin D overlap considerably in the ultraviolet (UV)B region.

Theoretically, sunscreens that inhibit erythema should also inhibit vitamin D synthesis.

To date, studies on the inhibitory effects of sunscreens on vitamin D synthesis have given conflicting results, possibly, in part, because people typically apply sunscreen suboptimally.

Many studies have design flaws.

What does this study add?

Sunscreens (sun protection factor, SPF 15) applied at sufficient thickness to inhibit sunburn during a week‐long holiday with a very high UV index still allow a highly significant improvement of serum 25‐hydroxyvitamin D₃ concentration.

An SPF 15 formulation with high UVA protection enables better vitamin D synthesis than a low UVA protection product. The former allows more UVB transmission.

Linked Editorial: https://doi.org/10.1111/bjd.18273.

https://doi.org/10.1111/bjd.18492 available online

https://www.bjdonline.com/article/optimal-sunscreen-use-during-a-sun-holiday-with-a-very-high-ultraviolet-index-allows-vitamin-d-synthesis-without-sunburn/

Mycosporine-Like Amino Acids for Skin Photoprotection

BACKGROUND

Excessive human exposure to solar ultraviolet radiation (UVR) continues to be a major public health concern, with skin cancer rates increasing year on year. The major protective measure is the use of synthetic UVR filters formulated into sunscreens, but there is a growing concern that some of these chemicals cause damage to delicate marine ecosystems. One alternative is the use of biocompatible mycosporine-like amino acids (MAA), which occur naturally in a wide range of marine species. Their role within nature is mainly thought to be photoprotective. However, their potential for human photoprotection is largely understudied.

OBJECTIVE

To review the role of MAA in nature and assess their potential as natural sunscreens for human skin photoprotection.

METHOD

A literature review of all relevant papers was conducted.

CONCLUSION

MAA are natural photostable compounds that are thought to offer photoprotection to marine species. Initially thought of as protective based on their absorption properties in the solar UVR spectrum, it is clear that MAA are multifunctional photoprotective compounds acting as chemical and biological anti-oxidants. This suggests that MAA may offer a novel eco-friendly approach to human skin photoprotection. Most studies have been carried out in vitro and current data strongly suggest that MAA have potential for development as natural biocompatible sunscreens that protect against a diverse range of solar UVR induced adverse effects on human health.

Development of the multispectral UV polarization reflectance imaging system (MUPRIS) for in situ monitoring of the UV protection efficacy of sunscreen on human skin

Background

Protection of the human skin from ultraviolet (UV) damage is one of the main issues in dermatology and cosmetology. The UV protection efficacy (UVPE) of the sunscreen film is decreased by sweat, sebum, and friction during the day. However, the technical relationship between the UVPE evaluated in a laboratory and the actual protection in daily use has not been clarified, because the UVPE measurement method in real‐life setting has not been established. This study aimed to develop a novel UVPE evaluation system that allows in situ monitoring of the UVPE in real‐life activities.

Methods

The multispectral UV polarization reflectance imaging system (MUPRIS) and a UVPE estimation algorithm were developed. The diffuse reflectance spectra were measured for a total of 48 sunscreen materials that were applied on 59 subjects. The UVPEs estimated from the diffuse reflectance spectra were compared with the in vivo SPFs. Finally, the UVPE before and after a marine leisure activity was evaluated using the MUPRIS as the practical use test.

Results

Compared with the conventional UV camera, the MUPRIS could visualize the applied sunscreen more clearly and showed good UVPE estimation accuracy (correlation coefficient for in vivo SPF, 0.82). In the practical use test, the degradation of the UVPE during a marine leisure activity was quantitatively monitored and was validated by the actual occurrence of sunburn.

Conclusions

A novel in situ UVPE monitoring tool had been successfully developed. It can strongly support the development of innovative sunscreen products that can perfectly protect customers against UV irradiation in real‐life situation.

Human health in relation to exposure to solar ultraviolet radiation under changing stratospheric ozone and climate

The Montreal Protocol has limited increases in the UV-B (280-315 nm) radiation reaching the Earth's surface as a result of depletion of stratospheric ozone. Nevertheless, the incidence of skin cancers continues to increase in most light-skinned populations, probably due mainly to risky sun exposure behaviour. In locations with strong sun protection programs of long duration, incidence is now reducing in younger age groups. Changes in the epidemiology of UV-induced eye diseases are less clear, due to a lack of data. Exposure to UV radiation plays a role in the development of cataracts, pterygium and possibly age-related macular degeneration; these are major causes of visual impairment world-wide. Photodermatoses and phototoxic reactions to drugs are not uncommon; management of the latter includes recognition of the risks by the prescribing physician. Exposure to UV radiation has benefits for health through the production of vitamin D in the skin and modulation of immune function. The latter has benefits for skin diseases such as psoriasis and possibly for systemic autoimmune diseases such as multiple sclerosis. The health risks of sun exposure can be mitigated through appropriate sun protection, such as clothing with both good UV-blocking characteristics and adequate skin coverage, sunglasses, shade, and sunscreen. New sunscreen preparations provide protection against a broader spectrum of solar radiation, but it is not clear that this has benefits for health. Gaps in knowledge make it difficult to derive evidence-based sun protection advice that balances the risks and benefits of sun exposure.

Sunscreen applied at ≥ 2 mg cm-2 during a sunny holiday prevents erythema, a biomarker of ultraviolet radiation-induced DNA damage and suppression of acquired immunity

BACKGROUND

Sun protection factor (SPF) is assessed with sunscreen applied at 2 mg cm^-2 . People typically apply around 0·8 mg cm^-2 and use sunscreen daily for holidays. Such use results in erythema, which is a risk factor for skin cancer.

OBJECTIVES

To determine (i) whether typical sunscreen use resulted in erythema, epidermal DNA damage and photoimmunosuppression during a sunny holiday, (ii) whether optimal sunscreen use inhibited erythema and (iii) whether erythema is a biomarker for photoimmunosuppression in a laboratory study.

METHODS

Holidaymakers (n = 22) spent a week in Tenerife (very high ultraviolet index) using their own sunscreens without instruction (typical sunscreen use). Others (n = 40) were given SPF 15 sunscreens with instructions on how to achieve the labelled SPF (sunscreen intervention). Personal ultraviolet radiation (UVR) exposure was monitored electronically as the standard erythemal dose (SED) and erythema was quantified. Epidermal cyclobutane pyrimidine dimers (CPDs) were determined by immunostaining, and immunosuppression was assessed by contact hypersensitivity (CHS) response.

RESULTS

There was no difference between personal UVR exposure in the typical sunscreen use and sunscreen intervention groups (P = 0·08). The former had daily erythema on five UVR-exposed body sites, increased CPDs (P < 0·001) and complete CHS suppression (20 of 22). In comparison, erythema was virtually absent (P < 0·001) when sunscreens were used at ≥ 2 mg cm^-2 . A laboratory study showed that 3 SED from three very different spectra suppressed CHS by around ~50%.

CONCLUSIONS

Optimal sunscreen use prevents erythema during a sunny holiday. Erythema predicts suppression of CHS (implying a shared action spectrum). Given that erythema and CPDs share action spectra, the data strongly suggest that optimal sunscreen use will also reduce CPD formation and UVR-induced immunosuppression.

Children sustain high levels of skin DNA photodamage, with a modest increase of serum 25-hydroxyvitamin D3 , after a summer holiday in Northern Europe

BACKGROUND

Childhood solar ultraviolet radiation (UVR) exposure increases the risk of skin cancer in adulthood, which is associated with mutations caused by UVR-induced cyclobutane pyrimidine dimers (CPD). Solar UVR is also the main source of vitamin D, essential for healthy bone development in children.

OBJECTIVES

To assess the impact of a 12-day Baltic Sea (54° N) beach holiday on serum 25-hydroxyvitamin D₃ [25(OH)D₃ ] and CPD in 32 healthy Polish children (skin types I-IV).

METHODS

Blood and urine were collected before and after the holiday and assessed for 25(OH)D₃ and excreted CPD, respectively, and personal UVR exposure was measured. Diaries were used to record sunbathing, sunburn and sunscreen use. Before- and after-holiday skin redness and pigmentation were measured by reflectance spectroscopy.

RESULTS

The average ± SD daily exposure UVR dose was 2·4 ± 1·5 standard erythema doses (SEDs), which is borderline erythemal. The mean concentration of 25(OH)D₃ increased (× 1·24 ± 0·19) from 64·7 ± 13·3 to 79·3 ± 18·7 nmol L^-1 (P < 0·001). Mean CPD increased 12·6 ± 10·0-fold from 26·9 ± 17·9 to 248·9 ± 113·4 fmol μmol^-1 creatinine (P < 0·001). Increased 25(OH)D₃ was accompanied by a very much greater increase in DNA damage associated with carcinogenic potential. Overall, skin type had no significant effects on behavioural, clinical or analytical outcomes, but skin types I/II had more CPD (unadjusted P = 0·0496) than skin types III/IV at the end of the holiday.

CONCLUSIONS

Careful consideration must be given to the health outcomes of childhood solar exposure, and a much better understanding of the risk-benefit relationships of such exposure is required. Rigorous photoprotection is necessary for children, even in Northern Europe.

Sunscreen use optimized by two consecutive applications

Sunscreen users are often inadequately protected and become sunburned. This study aimed to investigate how much two consecutive sunscreen applications increased the quantity of sunscreen applied and decreased the skin area left without sunscreen (missed area) compared to a single application. Thirty-one healthy volunteers wearing swimwear were included and applied sunscreen two consecutive times in a laboratory environment. Participants had pictures taken in black light before and after each application. As sunscreens absorb black light, the darkness of the skin increased with increasing amounts of sunscreen applied. We conducted a standard curve establishing a link between change in picture darkness and quantity of sunscreen. The quantity of sunscreen at selected skin sites as well as the percentage of missed area was determined after each application. Participants had missed a median of 20% of their available body surface after a single application. After double application they had missed 9%. The decrease in missed areas was significant for the whole body surface and for each of the body regions separately. The median participant had applied between 13% and 100% more sunscreen at the selected skin sites after double application than after single application. We recommend double application, especially before intense sun exposure.

Aware, motivated and striving for a 'safe tan': an exploratory mixed-method study of sun-protection during holidays

Background: This article presents an exploratory study, aiming to explore the correspondence between knowledge, motivation and sun-protection practices during holidays. Methods: Seventeen participants aged 21-62 years old, recruited from community settings took part in individual face-to-face semi-structured interviews, completed sun sensitivity questions and an objective assessment of sunscreen use. Holidaymakers' knowledge about sun-safe messages, intentions and perceptions of barriers and facilitators for sun-protection were assessed. Qualitative data were analysed using thematic analysis and integrated with quantitative data, using a pragmatic theory-informed approach to synthesise the findings. Results: Participants were well informed about sun-safe messages, highly motivated to protect themselves from solar UV radiation (UVR) and they perceived themselves as well protected. However, they did not seem to use effective protective practices. Sunscreen was the preferred method of sun-protection, but most participants used considerably less than the recommended amount and significantly overestimated the amount of time they could be safely exposed. Seeking shade was the least used method of sun-protection and covering-up strategies were mostly implemented as a partial protection (i.e. hats or sunglasses). The desire to reach an optimal balance between getting a tan and using sun-protection to avoid sunburns was preeminent. Several additional barriers and facilitators for sun-protection were identified. Conclusions: Holidaymakers might have a false sense of security when it comes to sun-exposure. They are aware of the need to protect from solar UVR, but the motive for a safe tan, the overreliance on sunscreen, the overestimation of the safe sun-exposure time for their skin type and the insufficient application of sunscreen leaves holidaymakers motivated to protect their skin at significant risk of overexposure, sunburn and skin cancer. Public health messages need to address how to implement effective sun-safe strategies.

Predictors of sun protection behaviours and sunburn among Australian adolescents

BACKGROUND

Excessive sun exposure and sunburn increase individuals' risk of skin cancer. It is especially important to prevent sunburn in childhood due to the higher relative risk of skin cancer across the life span compared to risk associated with sunburn episodes experienced later in life. This study examined demographic and attitudinal factors associated with engagement in a range of sun protection behaviours (wearing a hat, wearing protective clothing, staying in the shade, and staying indoors during the middle of the day) and the frequency of sunburn among Western Australian adolescents to provide insights of relevance for future sun protection campaigns.

METHODS

Cross-sectional telephone surveys were conducted annually with Western Australians between 2005/06 and 2014/15. The results from 4150 adolescents aged 14-17 years were used to conduct a path analysis of factors predicting various sun protection behaviours and sunburn.

RESULTS

Significant primary predictors of the sun protection behaviours included in the study were skin type (sun sensitivity), gender, tanning-related attitudes and behaviours, and perceived relevance of public service advertisements that advocate sun protection. Of the four sun protection behaviours investigated, staying in the shade and staying indoors during the middle of the day were associated with a lower frequency of sunburn.

CONCLUSION

There is a particular need to target sun protection messages at adolescent males who are less likely to engage in the most effective sun protection behaviours and demonstrate an increased propensity to experience sunburn. The results suggest that such future sun protection messages should include a focus on the importance of staying in the shade or indoors during periods of high UV radiation to increase awareness of the efficacy of these methods of avoiding skin cancer.

Major inter-personal variation in the increase and maximal level of 25-hydroxy vitamin D induced by UVB

Individual differences in vitamin D formation and metabolism after long-term UVB exposure were at least 131 nmol l⁻¹, even after eliminating most of the known external and behavioural sources of variation.

Skin Cancer Prevention, Tanning and Vitamin D: A Content Analysis of Print Media in Germany and Switzerland

BACKGROUND

Print media are a major source of health information.

OBJECTIVES

To analyse press coverage related to skin cancer prevention.

METHODS

We conducted a content analysis of print media articles pertaining to skin cancer prevention, solaria and vitamin D published in Germany and Switzerland over a 1-year period between 2012 and 2013.

RESULTS

Overall, 2,103 articles were analysed. Applying sunscreen was by far the most common sun protection recommendation. A considerable number of articles on solaria and vitamin D advocated exposure to ultraviolet radiation to enhance physical appearance and vitamin D photosynthesis, often without mentioning any precaution measures. In total, 26.8% of the articles contained misleading or erroneous statements mostly related to sunscreen use and vitamin D issues.

CONCLUSIONS

Print media can serve as powerful education tools to foster skin cancer prevention. However, misleading or erroneous reports may negatively impact sun-safe behaviour.

Skin temperature during sunbathing--relevance for skin cancer

It has been found that exposure to heat and infrared radiation (IR) can be carcinogenic, and that a combination of ultraviolet radiation (UVR) and IR possibly amplifies carcinogenesis. To investigate how the skin temperature is affected by sunbathing, we measured the skin temperature on 20 healthy volunteers over 6 days' sun holiday in Egypt. Temperatures were measured with an infrared thermometer gun at 8 skin sites on the volunteers while they were indoors in the morning and when sunbathing during the day. Skin temperatures were higher during sunbathing (33.5 °C ± 2.1 °C) (mean ± SD) than when indoors in the morning (32.6 °C ± 1.4 °C) (mean ± SD) (P < 0.0001). The average skin temperature for men was higher than for women by 0.40 °C in the morning (P = 0.02) and by 0.44 °C during sunbathing (P < 0.0001). Our results show that sunbathing has an impact on skin temperature, which possibly by activation of the heat shock response, is likely to contribute to the immediate and delayed effects of UV in a way that has to be found out in future studies.

The consequences for human health of stratospheric ozone depletion in association with other environmental factors

Ozone depletion, climate and human health.