Personal Ultraviolet Exposure Research Articles

Bismuth Oxychloride Nanoflakes Based Wearable Colorimetric Sensors for Efficient Monitoring of UV Exposure

Ultraviolet radiation from sunlight is essential for human health in many ways such as facilitating vitamin D synthesis while excessive exposure can cause adverse effects such as premature aging, sunburn, and skin cancers. In the USA, between 2007 and 2011, nearly five million adults were treated for skin cancer annually with average treatment costs of $8.1 billion each year. Hence, monitoring daily exposure to sunlight is essential to avoid developing health risks. Colorimetric UV sensors change color as a function of UV exposure, provide onsite information about the level of exposure, and can act as a personal wearable device to assist in making informed decisions on sunlight exposure. These sensors utilize radiation-induced reactions on a dye to produce a color change. We developed a BiOCl based wearable UV sensor for monitoring UV exposure where a white-to-black color transformation is induced due to the creation of oxygen vacancies in BiOCl. This color transformation is not quantifiable in bulk BiOCl; hence BiOCl was purposely dispersed on filter paper to form petal-like nanostructures that help quantify the color change. Four different dye molecules, 6-carboxyfluorescein, 5-carboxyfluorescein, rhodamine-B, and Prussian blue were evaluated, where 6-carboxyfluorescein gave the best color contrast. The sensor responds to UVA, UVB, and UVC and with proper UV filters can be made selective for specific UV radiations. This unique colorimetric UV sensor can help manage personal UV exposure and reduce the risk of sun exposure ailments.Reference: Kyle Troche, Kannan Ramaiyan, Timothy J. Boyle, Fernando H. Garzon, “Bismuth Oxychloride Nanoflakes Enabled High Sensitivity Colorimetric UV Dosimetry” ACS Appl. Nano. Mater. 2023, 6, 7.

Elastic TTC–PVA gel dosimeters for personal UV exposure measurements

This work presents a new personal chemical gel dosimeter containing a radiation-sensitive 2,3,5-triphenyltetrazolium chloride embedded in a poly(vinyl alcohol) matrix for UV radiation measurements. The dosimeter changes colour from colourless to pink under the influence of UV radiation, and colour intensity increases with increasing absorbed dose. The dosimeter was characterised using reflectance spectrophotometry for stability, repeatability, and dose–response, including dose sensitivity, threshold dose, as well as linear and dynamic dose range. The TTC–PVA dosimeter can be used to measure UVA, UVB, and UVC radiation, as well as actual solar radiation consisting of UVA and UVB radiation. As a result, it is promising for use as a personal dosimeter for people exposed to UV radiation from artificial and natural sources. The comfort of using the dosimeter would be ensured by its flexibility, which allows it to be properly adjusted to the curvatures of the human body.

UV Exposure during Cycling as a Function of Solar Elevation and Orientation

Although cycling is the most prevalent means of locomotion in the world, little research has been done in evaluating the ultraviolet (UV) radiation exposure of cyclists. In this study, a volunteer using a men’s bike was equipped with 10 miniature UV-meters at different body sites. Besides erythemally effective irradiance, the ratio of personal UV exposure to ambient UV radiation was determined for solar elevations up to 65°, taking into account different orientations with respect to the sun. This method provides a universal model that allows for the calculation of UV exposure whenever ambient UV radiation and solar elevation are available. Our results show that the most exposed body sites are the back, forearm, upper arm, and anterior thigh, receiving between 50% and 75% of ambient UV radiation on average. For certain orientations, this percentage can reach 105% to 110%. However, the risk of UV overexposure depends on ambient UV radiation. At lower solar elevations (<40°), the risk of UV overexposure clearly decreases.

Stratospheric ozone, UV radiation, and climate interactions

This assessment provides a comprehensive update of the effects of changes in stratospheric ozone and other factors (aerosols, surface reflectivity, solar activity, and climate) on the intensity of ultraviolet (UV) radiation at the Earth’s surface. The assessment is performed in the context of the Montreal Protocol on Substances that Deplete the Ozone Layer and its Amendments and Adjustments. Changes in UV radiation at low- and mid-latitudes (0–60°) during the last 25 years have generally been small (e.g., typically less than 4% per decade, increasing at some sites and decreasing at others) and were mostly driven by changes in cloud cover and atmospheric aerosol content, caused partly by climate change and partly by measures to control tropospheric pollution. Without the Montreal Protocol, erythemal (sunburning) UV irradiance at northern and southern latitudes of less than 50° would have increased by 10–20% between 1996 and 2020. For southern latitudes exceeding 50°, the UV Index (UVI) would have surged by between 25% (year-round at the southern tip of South America) and more than 100% (South Pole in spring). Variability of erythemal irradiance in Antarctica was very large during the last four years. In spring 2019, erythemal UV radiation was at the minimum of the historical (1991–2018) range at the South Pole, while near record-high values were observed in spring 2020, which were up to 80% above the historical mean. In the Arctic, some of the highest erythemal irradiances on record were measured in March and April 2020. For example in March 2020, the monthly average UVI over a site in the Canadian Arctic was up to 70% higher than the historical (2005–2019) average, often exceeding this mean by three standard deviations. Under the presumption that all countries will adhere to the Montreal Protocol in the future and that atmospheric aerosol concentrations remain constant, erythemal irradiance at mid-latitudes (30–60°) is projected to decrease between 2015 and 2090 by 2–5% in the north and by 4–6% in the south due to recovering ozone. Changes projected for the tropics are ≤ 3%. However, in industrial regions that are currently affected by air pollution, UV radiation will increase as measures to reduce air pollutants will gradually restore UV radiation intensities to those of a cleaner atmosphere. Since most substances controlled by the Montreal Protocol are also greenhouse gases, the phase-out of these substances may have avoided warming by 0.5–1.0 °C over mid-latitude regions of the continents, and by more than 1.0 °C in the Arctic; however, the uncertainty of these calculations is large. We also assess the effects of changes in stratospheric ozone on climate, focusing on the poleward shift of climate zones, and discuss the role of the small Antarctic ozone hole in 2019 on the devastating “Black Summer” fires in Australia. Additional topics include the assessment of advances in measuring and modeling of UV radiation; methods for determining personal UV exposure; the effect of solar radiation management (stratospheric aerosol injections) on UV radiation relevant for plants; and possible revisions to the vitamin D action spectrum, which describes the wavelength dependence of the synthesis of previtamin D3 in human skin upon exposure to UV radiation.Graphical abstract

Ultraviolet exposure of competitors during a Tokyo Olympic Sailing Regatta Test Event.

Overexposure to sunlight is the main cause of skin cancer. Photoprotection practices and sunburn play a crucial role in skin cancer prevention. This study aimed to quantify the risk of sun exposure and to evaluate photoprotection practices in Spanish sailors during Olympic competitions. Solar daily ultraviolet (UV) radiation cycle, personal UV dosimetry, photoprotection practices and sunburn checking were followed during three consecutive days of competition among sailors from the Spanish Olympic Sailing Team during a Tokyo Olympic Regatta Test Event. A total of 13 sailors (7 women), with mean age of 27.6 ± 4.7 years and sports experience of 17.7 ± 5.4 years, were studied. The most common phototypes were type III (53.8%) and type II (38.5%). The rate of sunburn checked was high (46.2%). The mean daily personal UV exposure received was 761.0 ± 263.6J/m2 , 3.0 ± 1.1 minimal erythemal dose and 7.6 ± 2.6 standard erythemal dose, seven times greater than the maximum permissible UV light exposure values for an 8 h working day. The use of a T-shirt was the most common practice (94.2%), followed by the use of shade (50.2%), hat/cap (44.0%), sunglasses (26.1%) and sunscreen (11.8%). Olympic sailor's studies presented high levels of UV radiation received, high rate of sunburn and insufficient adherence to sun-protective behaviours (especially, to use of sunscreen) to prevent sunburn, the main cause of skin cancer. Sport Federations should develop educational campaigns addressing sun-related exposure habits and photoprotection behaviours to reduce the risk of skin cancer among these athletes.

Bringing Light into Darkness-Comparison of Different Personal Dosimeters for Assessment of Solar Ultraviolet Exposure.

(1) Measuring personal exposure to solar ultraviolet radiation (UVR) poses a major challenges for researchers. Often, the study design determines the measuring devices that can be used, be it the duration of measurements or size restrictions on different body parts. It is therefore of great importance that measuring devices produce comparable results despite technical differences and modes of operation. Particularly when measurement results from different studies dealing with personal UV exposure are to be compared with each other, the need for intercomparability and intercalibration factors between different measurement systems becomes significant. (2) Three commonly used dosimeter types—(polysulphone film (PSF), biological, and electronic dosimeters)—were selected to perform intercalibration measurements. They differ in measurement principle and sensitivity, measurement accuracy, and susceptibility to inaccuracies. The aim was to derive intercalibration factors for these dosimeter types. (3) While a calibration factor between PSF and electronic dosimeters of about 1.3 could be derived for direct irradiation of the dosimeters, this was not the case for larger angles of incidence of solar radiation with increasing fractions of diffuse irradiation. Electronic dosimeters show small standard deviation across all measurements. For biological dosimeters, no intercalibration factor could be found with respect to PSF and electronic dosimeters. In a use case, the relation between steady-state measurements and personal measurements was studied. On average, persons acquired only a small fraction of the ambient radiation.

Evaluation of Personal Solar UV Exposure in a Group of Italian Dockworkers and Fishermen, and Assessment of Changes in Sun Protection Behaviours After a Sun-Safety Training

Evaluation of Personal Solar UV Exposure in a Group of Italian Dockworkers and Fishermen, and Assessment of Changes in Sun Protection Behaviours After a Sun-Safety Training

Review on Occupational Personal Solar UV Exposure Measurements

During leisure time, people can decide if they want to expose themselves to solar ultraviolet (UV) radiation and to what extent. While working, people do not have this choice. Outdoor workers are exposed to solar UV radiation (UVR) on a daily basis. This may pose a certain health risk, which can be estimated when the personal solar UVR exposure (PE) is known. During past decades, a variety of studies were conducted to measure PE of outdoor workers and our knowledge of the PE of outdoor workers has increased remarkably. As shown by this review, studies clearly indicate that PE of most outdoor workers exceeds the internationally proposed threshold limit value, which is comparable to 1.0 to 1.3 standard erythema dose (SED), respectively, to 1.1 to 1.5 UV Index received over one hour. Besides working in a high UVR environ, monotonic workflow (limited movement, nearly static posture) is a risk factor. In such cases, PE can be higher than ambient UVR. In this review, we provide also a list of milestones, depicting the progress and the most important findings in this field during the past 45 years. However, in many respects our knowledge is still rudimentary, for several reasons. Different measuring positions have been used so that measured PE is not comparable. Few studies were designed to enable the extension of measured PE to other locations or dates. Although the importance of a proper calibration of the measuring devices in respect to the changing solar spectrum was pointed out from the beginning, this is often not performed, which leads to high uncertainties in the presented PE levels. At the end of our review, we provide some key points, which can be used to evaluate the quality of a study respectively to support the design of future studies.

Review of Wearable and Portable Sensors for Monitoring Personal Solar UV Exposure.

Sunlight is one of the main environmental resources that keeps all the organisms alive on earth. The ultraviolet (UV) radiation from the sun is essential for vitamin D synthesis in the human body, which is crucial for bone and muscle health. In addition, sun exposure also helps to reduce the risk of some cardiovascular diseases and cancers. However, excessive UV exposure can lead to adverse effects, including some eye diseases, premature aging, sunburn and skin cancers. The solar UV irradiance itself depends on many environmental factors. In fact, the UV index reported in weather forecasts is an estimation under cloudless conditions. Personal UV exposure also depends on one's outdoor activities and habits. Furthermore, the UV intake depends on the skin sensitivity. Therefore, there is a need for research into monitoring the optimal daily UV exposure for health benefits, without developing potential health risks. To facilitate the monitoring of solar UV intensity and cumulative dose, a variety of UV sensors have been developed in the past few decades and many are commercially available. Examples of sensors being marketed are: portable UV dosimeter, wearable UV radiometer, personal UV monitor, and handheld Solarmeter®. Some of the UV sensors can be worn as personal health monitors, which promote solar exposure protection. The paper provides a comprehensive review of the wearable and portable UV sensors for monitoring personal UV exposure, including a discussion of their unique advantages and limitations. Proposals are also presented for possible future research into reliable and practical UV sensors for personal UV exposure monitoring.

"Beach Lifeguards' Sun Exposure and Sun Protection in Spain".

BackgroundSunburn is the main avoidable cause of skin cancer. Beach lifeguards spend many hours exposed to the effects of solar radiation during their work day, precisely at times of the year when levels of solar irradiation are highest. The aim of this study is to quantify the risk to beach lifeguards of sun exposure.MethodsA descriptive cross-sectional study was carried out in the Western Costa del Sol, southern Spain, during the summer of 2018. The research subjects were recruited during a skin cancer prevention course for beach lifeguards. All participants were invited to complete a questionnaire on their habits, attitudes, and knowledge related to sun exposure. In addition, ten were specially monitored using personal dosimeters for three consecutive days, and the results were recorded in a photoprotection diary. A descriptive analysis (mean and standard deviation for the quantitative variables) was performed, and inter-group differences were evaluated using the Mann–Whitney U test.ResultsTwo hundred fifteen lifeguards completed the questionnaire, and 109 met the criteria for inclusion in this analysis. The mean age was 23.8 years (SD: 5.1), 78.0% were male, 71.5% were phototype III or IV (Fitzpatrick's phototype), and 77.1% had experienced at least one painful sunburn during the previous summer. The mean daily personal ultraviolet exposure per day, the minimal erythema dose, and the standard erythema dose, in J/m2, were 634.7 [standard deviation (SD): 356.2], 2.5 (SD: 1.4) and 6.35 (SD: 3.6), respectively.ConclusionBeach lifeguards receive very high doses of solar radiation during the work day and experience correspondingly high rates of sunburn. Intervention strategies to modify their sun exposure behavior and working environment are necessary to reduce the risk of skin cancer for these workers and to promote early diagnosis of the disease.

Possibilities to estimate the personal UV radiation exposure from ambient UV radiation measurements.

People are exposed to solar ultraviolet radiation (UVR) throughout their entire lives. Exposure to UVR is vital but also poses serious risks. The quantification of human UVR exposure is a complex issue. Personal UVR exposure is related to ambient UVR as well as to a variety of factors such as the orientation of the exposed anatomical site with respect to the sun and the duration of exposure. This is mainly determined by personal behaviour. A variety of efforts have been made in the past to measure or model the personal UVR exposure of people and often personal UVR exposure has been expressed as the percentage of ambient UVR. On the other hand, ambient UVR is being monitored at a variety of places and measurements are available even online. This suggests that both the knowledge of personal UVR exposure and measurements of ambient UVR is required. In this paper, a summary on the different methods, which use ambient UVR measurements to estimate personal UVR exposure of people, as well as a few examples, are given. Advantages and disadvantages will be discussed as well as possibilities and limitations. This also includes an overview of appropriate terminology, units and basic statistic parameters to describe personal UVR exposure.

Use of Electronic UV Dosimeters in Measuring Personal UV Exposures and Public Health Education

The performance limits of electronic ultraviolet (EUV) dosimeters, which use AlGaN Schottky photodiodes as the ultraviolet radiation (UVR) sensing element to measure personal erythemally weighted UVR exposures, were investigated via a direct comparison with meteorological-grade reference instruments. EUV dosimeters with two types of AlGaN Schottky photodiode were compared to second-generation ‘Robertson–Berger type’ broadband erythemal radiometers. This comparison was done by calculating correction factors for the deviations of the spectral responsivity of each instrument from the CIE erythemal action spectrum and for deviations in their angular response from the ideal cosine response of flat surfaces and human skin. Correction factors were also calculated to convert the output of these instruments to vitamin D-weighted UV irradiances. These comparisons showed that EUV dosimeters can be engineered with spectral responsivities and cosine response errors approaching those of Robertson–Berger type radiometers, making them very acceptable for use in human UVR exposure and sun safety behaviour studies, provided appropriate side-by-side calibrations are performed. Examples of these calibrations and the effect of EUV dosimeter sampling rates on the calculation of received erythemal UVR doses and erythemal UVR dose rates are provided, as well as brief descriptions of their use in primary skin cancer prevention programmes, handheld meters, and public health displays.

Abstract PR01: Genomic UV-hypersensitive sites as sentinels for personal UV exposure

Abstract The largest risk factor for skin cancers such as melanoma is past sun exposure, so an objective measurement of traces of an individual’s sun history would allow a general practitioner to identify people who should be monitored for early cancer detection. If the genome contains outlier DNA sequences hypersensitive to environmental agents such as ultraviolet light (UV), these would be genomic dosimeters for monitoring personal carcinogen exposure and would facilitate noninvasive measurements on small skin samples. Such DNA sites might also allow UV to drive direct changes in cell physiology rather than acting through rare mutations. New methods, adductSeq and freqSeq, tagged rare UV-induced cyclobutane pyrimidine dimers (CPDs) and provided statistical resolution to quantify rare lesions at single-base resolution across the genome. Primary human melanocytes, but not fibroblasts, carried spontaneous apurinic sites and TG sequence lesions more frequent than UV-induced CPDs. UV exposure revealed hyperhotspots acquiring CPDs up to 200-fold more frequently than the genomic average; these were 20-fold more prevalent in melanocytes. Hyperhotspots were disproportionately located near genes, particularly for RNA-binding proteins, with the most-recurrent hyperhotspots at a fixed position within two motifs. One motif occurred at ETS1 transcription factor binding sites, known to be UV targets, and at sites of mTOR/TOP-tract translation regulation; the second occurred at a sequence that developed delayed CPDs after UV exposure, repaired CPDs slowly, and had accumulated CPDs prior to the experiment. Melanocyte CPD hyperhotspots aligned precisely with recurrent UV signature mutations in individual gene promoters of melanomas and with known cancer drivers. At sunburn levels of UV exposure, every cell would have a hyperhotspot CPD in each of the ~20 cell pathways targeted, rendering CPD hyperhotspots epigenetic marks. This abstract is also being presented as Poster A28. Citation Format: Sanjay Premi, Lynn Han, Sameet Mehta, James Knight, Dejian Zhao, Antonella Bacchiocchi, Ruth Halaban, Meg A. Palmatier, Karl Kornacker, Douglas E. Brash. Genomic UV-hypersensitive sites as sentinels for personal UV exposure [abstract]. In: Proceedings of the AACR Special Conference on Environmental Carcinogenesis: Potential Pathway to Cancer Prevention; 2019 Jun 22-24; Charlotte, NC. Philadelphia (PA): AACR; Can Prev Res 2020;13(7 Suppl): Abstract nr PR01.

Measured UV Exposures of Ironman, Sprint and Olympic-Distance Triathlon Competitors

Triathletes present an extreme case of modelled behaviour in outdoor sport that favours enhanced exposure to solar ultraviolet radiation. This research presents personal solar ultraviolet exposures, measured using all-weather polysulphone film dosimeters, to triathletes during the distinct swimming, cycling and running stages of competitive Sprint, Olympic and Ironman events conducted within Australia and New Zealand. Measurements of exposure are made for each triathlon stage using film dosimeters fixed at a single site to the headwear of competing triathletes. Exposures are expressed relative to the local ambient and as absolute calibrated erythemally effective values across a total of eight triathlon courses (two Ironman, one half Ironman, one Olympic-distance, and four Sprint events). Competitor exposure results during training are also presented. Exposures range from between 0.2 to 6.8 SED/h (SED: standard erythema dose) depending upon the time of year, the local time of each event and cloud conditions. Cycle stage exposures can exceed 20 SED and represent the highest exposure fraction of any triathlon (average = 32%). The next highest stage exposure occurred during the swim (average = 28%), followed by the run (average = 26%). During an Ironman, personal competitor exposures exceed 30 SED, making triathlon a sporting discipline with potentially the highest personal ultraviolet exposure risk.

The Early Days of Personal Solar Ultraviolet Dosimetry

In the early 1970s, environmental conservationists were becoming concerned that a reduction in the thickness of the atmospheric ozone layer would lead to increased levels of ultraviolet (UV) radiation at ground level, resulting in higher population exposure to UV and subsequent harm, especially a rise in skin cancer. At the time, no measurements had been reported on the normal levels of solar UV radiation which populations received in their usual environment, so this lack of data, coupled with increasing concerns about the impact to human health, led to the development of simple devices that monitored personal UV exposure. The first and most widely used UV dosimeter was the polymer film, polysulphone, and this review describes its properties and some of the pioneering studies using the dosimeter that led to a quantitative understanding of human exposure to sunlight in a variety of behavioral, occupational, and geographical settings.

Does polygenic risk influence associations between sun exposure and melanoma? A prospective cohort analysis.

Melanoma develops as the result of complex interactions between sun exposure and genetic factors. However, data on these interactions from prospective studies are scant. To quantify the association between ambient and personal ultraviolet exposure and incident melanoma in a large population-based prospective study of men and women residing in a setting of high ambient ultraviolet radiation, and to examine potential gene-environment interactions. Data were obtained from the QSkin Sun and Health Study, a prospective cohort study of men and women aged 40-69 years, randomly sampled from the Queensland population in 2011. Participants were genotyped and assessed for ultraviolet exposure. Among participants with genetic data (n = 15373), 420 (2·7%) developed cutaneous melanoma (173 invasive, 247 insitu) during a median follow-up time of 4·4 years. Country of birth, age at migration, having > 50 sunburns in childhood or adolescence, and a history of keratinocyte cancer or actinic lesions were significantly associated with melanoma risk. An interaction with polygenic risk was suggested: among people at low polygenic risk, markers of cumulative sun exposure (as measured by actinic damage) were associated with melanoma. In contrast, among people at high polygenic risk, markers of high-level early-life ambient exposure (as measured by place of birth) were associated with melanoma (hazard ratio for born in Australia vs. overseas 3·16, 95% confidence interval 1·39-7·22). These findings suggest interactions between genotype and environment that are consistent with divergent pathways for melanoma development. What's already known about this topic? The relationship between sun exposure and melanoma is complex, and exposure effects are highly modified by host factors and behaviours. The role of genotype on the relationship between ultraviolet radiation exposure and melanoma risk is poorly understood. What does this study add? We found that country of birth, age at migration, sunburns in childhood or adolescence, and history of keratinocyte cancer or actinic lesions were significantly associated with melanoma risk, while other measures of continuous or more intermittent patterns of sun exposure were not. We found evidence for gene-environment interactions that are consistent with divergent pathways for melanoma development. Linked Comment:Cust. Br J Dermatol 2020; 183:205-206. Plain language summary available online.

Assessing recall of personal sun exposure by integrating UV dosimeter and self-reported data with a network flow framework.

BackgroundMelanoma survivors often do not engage in adequate sun protection, leading to sunburn and increasing their risk of future melanomas. Melanoma survivors do not accurately recall the extent of sun exposure they have received, thus, they may be unaware of their personal UV exposure, and this lack of awareness may contribute towards failure to change behavior. As a means of determining behavioral accuracy of recall of sun exposure, this study compared subjective self-reports of time outdoors to an objective wearable sensor. Analysis of the meaningful discrepancies between the self-report and sensor measures of time outdoors was made possible by using a network flow algorithm to align sun exposure events recorded by both measures. Aligning the two measures provides the opportunity to more accurately evaluate false positive and false negative self-reports of behavior and understand participant tendencies to over- and under-report behavior.Methods39 melanoma survivors wore an ultraviolet light (UV) sensor on their chest while outdoors for 10 consecutive summer days and provided an end-of-day subjective self-report of their behavior while outdoors. A Network Flow Alignment framework was used to align self-report and objective UV sensor data to correct misalignment. The frequency and time of day of under- and over-reporting were identified.FindingsFor the 269 days assessed, the proposed framework showed a significant increase in the Jaccard coefficient (i.e. a measure of similarity between self-report and UV sensor data) by 63.64% (p < .001), and significant reduction in false negative minutes by 34.43% (p < .001). Following alignment of the measures, under-reporting of sun exposure time occurred on 51% of the days analyzed and more participants tended to under-report than to over-report sun exposure time. Rates of under-reporting of sun exposure were highest for events that began from 12-1pm, and second-highest from 5-6pm.ConclusionThese discrepancies may reflect lack of accurate recall of sun exposure during times of peak sun intensity (10am–2pm) that could ultimately increase the risk of developing melanoma. This research provides technical contributions to the field of wearable computing, activity recognition, and identifies actionable times to improve participants’ perception of their sun exposure.

Review on Nonoccupational Personal Solar UV Exposure Measurements.

Solar ultraviolet (UV) radiation follows people during their whole life. Exposure to UV radiation is vital but holds serious risks, too. The quantification of human UV exposure is a complex issue. UV exposure is directly related to incoming UV radiation as well as to a variety of factors such as the orientation of the exposed anatomical site with respect to the sun and the duration of exposure. The use of badge-sensors allows assessing the UV exposure of differently oriented body sites. Such UV devices have been available for over 40 years, and a variety of measuring campaigns have been undertaken since then. This study provides an overview of those studies which reported measurements of the personal UV exposure (PE) during outdoor activities of people not related to their occupation. This overview is given chronologically to show the progress of knowledge in this research and is given with respect to different activities. Special focus is put on the ratio of personal exposure to ambient UV radiation. This ratio, when given as a function of solar elevation, allows estimating PE at any other location or date if ambient UV radiation is known.

Time and Place as Modifiers of Personal UV Exposure.

It is a common belief that, if we want to limit our sun exposure during outdoor recreational activities and holidays in order to avoid sunburn or reduce our risk of skin cancer, we need to reach for the bottle of sunscreen or cover up with clothing. As important as these measures are, there is another way to enjoy our time outdoors and still benefit from the experience. In this article, we consider the impact of time, place, and behaviour outdoors on our exposure to solar ultraviolet (UV) radiation. Some of the simple actions we can take in controlling our UV exposure include being aware of the position of the sun in the sky, understanding how we can use the UV index to guide our outdoor exposure, and the importance of reducing our sun exposure around the middle of the day. Finally we review our preferred holiday activities and destinations, and the influence of outdoor leisure pursuits. By planning where and when we spend our leisure time in the sun, we can maximise our enjoyment whilst limiting our UV exposure.

An Inexpensive High-Temporal Resolution Electronic Sun Journal for Monitoring Personal Day to Day Sun Exposure Patterns.

Exposure to natural sunlight, specifically solar ultraviolet (UV) radiation contributes to lifetime risks of skin cancer, eye disease, and diseases associated with vitamin D insufficiency. Improved knowledge of personal sun exposure patterns can inform public health policy; and help target high-risk population groups. Subsequently, an extensive number of studies have been conducted to measure personal solar UV exposure in a variety of settings. Many of these studies, however, use digital or paper-based journals (self-reported volunteer recall), or employ cost prohibitive electronic UV dosimeters (that limit the size of sample populations), to estimate periods of exposure. A cost effective personal electronic sun journal (ESJ) built from readily available infrared photodiodes is presented in this research. The ESJ can be used to complement traditional UV dosimeters that measure total biologically effective exposure by providing a time-stamped sun exposure record. The ESJ can be easily attached to clothing and data logged to personal devices (including fitness monitors or smartphones). The ESJ improves upon self-reported exposure recording and is a cost effective high-temporal resolution option for monitoring personal sun exposure behavior in large population studies.