Enhanced joint hybrid deep neural network explainable artificial intelligence model for 1-hr ahead solar ultraviolet index prediction.

BACKGROUND AND OBJECTIVE: Exposure to solar ultraviolet (UV) radiation can cause malignant keratinocyte cancer and eye disease. Developing a user-friendly, portable, real-time solar UV alert system especially or wearable electronic mobile devices can help reduce the exposure to UV as a key measure for personal and occupational management of the UV risks. This research aims to design artificial intelligence-inspired early warning tool tailored for short-term forecasting of UV index (UVI) integrating satellite-derived and ground-based predictors for Australian hotspots receiving high UV exposures. The study further improves the trustworthiness of the newly designed tool using an explainable artificial intelligence approach. METHODS: An enhanced joint hybrid explainable deep neural network model (called EJH-X-DNN) is constructed involving two phases of feature selection and hyperparameter tuning using Bayesian optimization. A comprehensive assessment of EJH-X- DNN is conducted with six other competing benchmarked models. The proposed model is explained locally and globally using robust model-agnostic explainable artificial intelligence frameworks such as Local Interpretable Model-Agnostic Explanations (LIME), Shapley additive explanations (SHAP), and permutation feature importance (PFI). RESULTS: The newly proposed model outperformed all benchmarked models for forecasting hourly horizons UVI, with correlation coefficients of 0.900, 0.960, 0.897, and 0.913, respectively, for Darwin, Alice Springs, Townsville, and Emerald hotspots. According to the combined local and global explainable model outcomes, the site-based results indicate that antecedent lagged memory of UVI and solar zenith angle are influential features. Predictions made by EJH-X-DNN model are strongly influenced by factors such as ozone effect, cloud conditions, and precipitation. CONCLUSION: With its superiority and skillful interpretation, the UVI prediction system reaffirms its benefits for providing real-time UV alerts to mitigate risks of skin and eye health complications, reducing healthcare costs and contributing to outdoor exposure policy.

Serial Cross-Sectional Observations of Sun-Protective Behaviors at an Annual Outdoor Motorsport Event in Tropical Queensland, Australia.

Skin cancer, the most prevalent cancer in Caucasians residing at low latitudes, can primarily be prevented by avoiding overexposure to sunlight. Serial cross-sectional observations were conducted at an outdoor motorsport event held in Townsville, Queensland each July (Southern winter) to determine whether sun-protection habits changed over time. Most (71.1%) of the 1337 attendees observed (97.6% lightly pigmented skin, 64.0% male) wore a hat (any style shading the face), while few (18.5%) wore three-quarter or full-length sleeves. While hat-wearing rates (any style) were similar in 2009 (326, 72.6%) and 2013 (625, 70.4%), the use of sun-protective styles (wide-brimmed/bucket/legionnaires) decreased from 29.2% to 18.6% over the same period, primarily because the use of sun-protective hats halved (from 28.7% to 14.0%) among females, while decreasing from 29.4% to 21.1% in males. Although relatively few individuals wore sun-protective (three-quarter-length or full-length) sleeves regardless of year (OR = 0.117, P < 0.0001), encouragingly, the use of sun-protective sleeves more than doubled between 2009 (10.5%) and 2013 (22.5%). Interestingly females, albeit the minority, at this sporting event were less likely to wear a hat (OR = 0.473, P < 0.0001) than males. These findings highlight the need for continued momentum toward skin cancer primary prevention through sun protection with a dedicated focus on outdoor sporting settings.

The Playground Shade Index: A New Design Metric for Measuring Shade and Seasonal Ultraviolet Protection Characteristics of Parks and Playgrounds.

Current shading strategies used to protect outdoor playgrounds from harmful solar radiation include the placement of artificial cloth weaves or permanent roofing over a playground site, planting trees in proximity to playground equipment, and using vegetation or surface texture variations to cool playground surfaces. How and where an artificial shade structure is placed or a tree is planted to maximize the shade protection over specific playground areas, requires careful assessment of local seasonal sun exposure patterns. The Playground Shade Index (PSI) is introduced here as a design metric to enable shade and solar ultraviolet exposure patterns to be derived in an outdoor space using conventional aerial views of suburban park maps. The implementation of the PSI is demonstrated by incorporating a machine learning design tool to classify the position of trees from an aerial image, thus enabling the mapping of seasonal shade and ultraviolet exposure patterns within an existing 7180 m2 parkland. This is achieved by modeling the relative position of the sun with respect to nearby buildings, shade structures, and the identified evergreen and deciduous tree species surrounding an outdoor playground.

A Case Study of UV Exposure Risk in Sydney during the 2019/2020 New South Wales Bushfires.

During summer of 2019/2020, Sydney, Australia, experienced several days of extreme air pollution and low visibility due to bushfires. This research presents a case study that investigates the erythemal UV irradiance and resulting 1 h erythemal and 8 h actinic exposures during the worst of these days. Air quality, meteorological and UV data used in the analysis were readily available online or by request from governmental agencies. Analysis showed that even for the lowest visibility day (which had a minimum visibility of less than a kilometer) on 10 December 2019, there was a cumulative 1 h erythemal UV exposure of over 4 SED (standard erythema dose) and a cumulative 8 h exposure of 17 SED by the late afternoon. The 1 h exposure exceeded that of a minimum erythemal dose. Even on this extremely hazy day, these cumulative exposures are enough to exceed the recommended daily exposure limit for actinic exposures weighted with the health sensitivity spectrum for the skin and eyes set by the International Commission of Non-Ionizing Radiation Protection.

Wearable ultraviolet radiation sensors for research and personal use.

Skin cancers are strongly linked to personal exposure to ultraviolet (UV) radiation, yet UV exposure is also the most preventable risk factor. People are exposed to UV rays when they engage in outdoor activities, particularly exercise, which is an important health behavior. Thus, researchers and the general public have shown increasing interest in measuring UV exposure using wearable sensors during outdoor physical activity. However, minimal research exists at the intersection of UV sensors, personal exposure, adaptive behavior due to exposures, and risk of skin damage. Recent years have seen an influx of new consumer-based and research-based UV-sensing technologies with wide-ranging form factors and purposes to fill this research gap, yet a thorough review of available sensors for specific purposes does not exist. Hence, the overall goal of this state-of-the-art review is to synthesize the current academic and gray literature surrounding personal UV-sensing technologies. Peer-reviewed journal articles and "gray literature," such as working papers, manuals, and UV sensor websites, were reviewed, assessing attributes of UV wearables marketed for research use, personal use, or both. Overall, 13 wearable UV sensors are available for personal use and/or research applications. These sensors vary from electronic to photochromic, with large differences in price, data outputs, accuracy, and precision. Recommendations are provided for which sensors are most suitable for various types of research or public use. Notably, the review findings will help guide researchers in future studies assessing UV exposure during physical activity.

Solar Blue Light Radiation Enhancement during Mid to Low Solar Elevation Periods under Cloud Affected Skies.

Solar blue-violet wavelengths (380-455 nm) are at the high energy end of the visible spectrum; referred to as "high energy visible" (HEV). Both chronic and acute exposure to these wavelengths has been often highlighted as a cause for concern with respect to ocular health. The sun is the source of HEV which reaches the Earth's surface either directly or after scattering by the atmosphere and clouds. This research has investigated the effect of clouds on HEV for low solar elevation (solar zenith angles between 60° and 80°), simulating time periods when the opportunity for ocular exposure in global populations with office jobs is high during the early morning and late afternoon. The enhancement of "bluing" of the sky due to the influence of clouds was found to increase significantly with the amount of cloud. A method is presented for calculating HEV irradiance at sub-tropical latitudes from the more commonly measured global solar radiation (300-3000 nm) for all cases when clouds do and do not obscure the sun. The method; when applied to global solar radiation data correlates well with measured HEV within the solar zenith angle range 60° and 80° (R2 = 0.82; mean bias error (MBE) = -1.62%, mean absolute bias error (MABE) = 10.3% and root mean square error (RMSE) = 14.6%). The technique can be used to develop repeatable HEV hazard evaluations for human ocular health applications.

Biologically effective solar ultraviolet exposures and the potential skin cancer risk for individual gold medalists of the 2020 Tokyo Summer Olympic Games.

Personal solar ultraviolet radiation exposure models were developed for 144 Olympic events scheduled outdoors from across the 33 sport disciplines that will compete in Tokyo between 24 July and 9 August 2020. Ambient exposure models were developed from existing atmospheric parameters measured over Tokyo (35.7°N 139.7°E) and were used to weight erythemally effective solar ultraviolet exposure to gold medalists, taking into account body posture and expected protection by competitor's clothing which was assessed in comparison to respective medalists of the 2016 Rio Olympics. Individual exposure models consider the ultraviolet surface albedo (lawn, concrete, water or sand) and timing of daily events held within Olympic venues. Exposure assessments are presented, including assessments of all preliminary rounds and qualifiers. Within scheduled outdoor events, we award first place (representing the highest and most harmful UV exposure) to the women's tennis singles (1680 J/m2), second to men's golf (1530 J/m2) and third to the men's cycling road race (941 J/m2) for the highest expected erythemally effective solar ultraviolet radiation exposures of the 2020 Tokyo Games. The highest expected solar ultraviolet exposures for nations expected to win greater than three gold medals among the outdoor events were found to occur in athletes from Kenya followed closely by the United States and Hungary. Gold medalists from South Korea were found to demonstrate the highest level of sun protection due to clothing at the 2016 Rio Games, and are thus expected to receive the greatest relative reduction in erythemally effective exposure during the 2020 Tokyo Games.

Seasonal Minimum and Maximum Solar Ultraviolet Exposure Measurements of Classroom Teachers Residing in Tropical North Queensland, Australia.

The risk of keratinocyte skin cancer, malignant melanoma and ultraviolet radiation (UVR)-induced eye disease is disproportionately higher in Australia and New Zealand compared to equivalent northern hemisphere latitudes. While many teachers are aware of the importance of reinforcing sun safety messages to students, many may not be aware of the considerable personal exposure risk while performing outdoor duties in locations experiencing high to extreme ambient UVR year-round. Personal erythemally effective exposure of classroom teachers in tropical Townsville (19.3°S) was measured to establish seasonal extremes in exposure behavior. Mean daily personal exposure was higher in winter (91.2 J m-2 , 0.91 Standard Erythema Dose [SED]) than summer (63.3 J m-2 , 0.63 SED). The range of exposures represents personal exposures that approximate current national guidelines for Australian workers at the study latitude of approximately 1.2 SED (30 J m-2 effective to the International Commission on Non-Ionizing Radiation Protection). Similar proportions of teachers spent more than 1 h outdoors per day in winter (28.6%) and summer (23.6%) as part of their teaching duties with seasonal differences having little effect on the time of exposure. Personal exposures for teachers peaked during both seasons near school meal break times at 11:00 am and 1:00 pm, respectively.

A Pilot Observational Study of Environmental Summertime Health Risk Behavior in Central Brisbane, Queensland: Opportunities to Raise Sun Protection Awareness in Australia's Sunshine State.

Melanoma skin cancer rates in Queensland exceed the national Australian incidence rate, which together with New Zealand are recognized as the world's highest. Incidence is especially high among younger members of the population. In this study, the sun-protective behaviors of urban Queenslanders (n = 752) going about their day-to-day activities during a midweek noon time hourly period were observed on a summer's day in central Brisbane (27.47°S, 153.03°E), Australia. Observed sun protection practices were poor, given the time of year and peak solar noon period of the study. More individuals (n = 249; 33.1%) were seen wearing sunglasses than a hat (n = 101; 13.4%). Ninety-three individuals were actively engaging with mobile phones (phone in hand). A further 231 individuals (30.7%) were observed with a mobile phone on them. Opportunities to modify group behavior based on mobile phone sun protection notifications and to engage with "at risk" members of the Queensland population are considered from the variable codependencies examined in this study, including the influence of social group size, observed sun protection and mobile phone use. Our preliminary findings suggest that mobile phones provide an underutilized opportunity for delivering tailored skin cancer prevention messaging.

The geospatial relationship of pterygium and senile cataract with ambient solar ultraviolet in tropical Ecuador.

Tropical Ecuador presents a unique climate in which we study the relationship between the ambient levels of solar ultraviolet radiation and eye disease in the absence of a latitudinal gradient. The national distribution of surface ultraviolet, taking into account MODIS and OMI satellite observation of aerosol, ozone, surface albedo, local elevation and cloud fractions measured during 2011, was compared with the national pterygium (WHO ICD H11) and senile cataract (WHO ICD H25) incidence projected from the 2010 National Institute of Statistics and Census (Ecuador). Public Health Ministry projections for age categories 0 to 39, 40 to 59 and 60+ years were compared to surface ultraviolet irradiance data in 1040 parishes. Correlations drawn between modelled surface ultraviolet and eye disease incidence show a significant increase in both pterygium and senile cataract in the highest ambient exposure regions of the Pacific coast and western lowlands with incidence rates of 34.39 and 16.17 per 100 000 residents respectively. The lowest rates of incidence for pterygium (6.89 per 100 000) and senile cataract (2.90 per 100 000) were determined in high altitude sites and are attributed here to increased daily cloud fraction for parishes located in the Andean mountain range. The South American Andes experience the highest solar UV exposures on Earth and report frequent high incidence of keratinocyte cancer. Our results show the high Andes to be the location of the lowest eye disease incidence suggesting that both pterygium and senile cataract are the result of cumulative exposure to solar ultraviolet. These findings have clear implications for the agricultural workers and fishermen of the lowland districts of Ecuador, contrary to conventional understanding that greater risks are faced in locations of high altitude.

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.

Very short-term reactive forecasting of the solar ultraviolet index using an extreme learning machine integrated with the solar zenith angle.

Exposure to erythemally-effective solar ultraviolet radiation (UVR) that contributes to malignant keratinocyte cancers and associated health-risk is best mitigated through innovative decision-support systems, with global solar UV index (UVI) forecast necessary to inform real-time sun-protection behaviour recommendations. It follows that the UVI forecasting models are useful tools for such decision-making. In this study, a model for computationally-efficient data-driven forecasting of diffuse and global very short-term reactive (VSTR) (10-min lead-time) UVI, enhanced by drawing on the solar zenith angle (θs) data, was developed using an extreme learning machine (ELM) algorithm. An ELM algorithm typically serves to address complex and ill-defined forecasting problems. UV spectroradiometer situated in Toowoomba, Australia measured daily cycles (0500-1700h) of UVI over the austral summer period. After trialling activations functions based on sine, hard limit, logarithmic and tangent sigmoid and triangular and radial basis networks for best results, an optimal ELM architecture utilising logarithmic sigmoid equation in hidden layer, with lagged combinations of θs as the predictor data was developed. ELM's performance was evaluated using statistical metrics: correlation coefficient (r), Willmott's Index (WI), Nash-Sutcliffe efficiency coefficient (ENS), root mean square error (RMSE), and mean absolute error (MAE) between observed and forecasted UVI. Using these metrics, the ELM model's performance was compared to that of existing methods: multivariate adaptive regression spline (MARS), M5 Model Tree, and a semi-empirical (Pro6UV) clear sky model. Based on RMSE and MAE values, the ELM model (0.255, 0.346, respectively) outperformed the MARS (0.310, 0.438) and M5 Model Tree (0.346, 0.466) models. Concurring with these metrics, the Willmott's Index for the ELM, MARS and M5 Model Tree models were 0.966, 0.942 and 0.934, respectively. About 57% of the ELM model's absolute errors were small in magnitude (±0.25), whereas the MARS and M5 Model Tree models generated 53% and 48% of such errors, respectively, indicating the latter models' errors to be distributed in larger magnitude error range. In terms of peak global UVI forecasting, with half the level of error, the ELM model outperformed MARS and M5 Model Tree. A comparison of the magnitude of hourly-cumulated errors of 10-min lead time forecasts for diffuse and global UVI highlighted ELM model's greater accuracy compared to MARS, M5 Model Tree or Pro6UV models. This confirmed the versatility of an ELM model drawing on θsdata for VSTR forecasting of UVI at near real-time horizon. When applied to the goal of enhancing expert systems, ELM-based accurate forecasts capable of reacting quickly to measured conditions can enhance real-time exposure advice for the public, mitigating the potential for solar UV-exposure-related disease.

Solar ultraviolet and the occupational radiant exposure of Queensland school teachers: A comparative study between teaching classifications and behavior patterns.

Classroom teachers located in Queensland, Australia are exposed to high levels of ambient solar ultraviolet as part of the occupational requirement to provide supervision of children during lunch and break times. We investigated the relationship between periods of outdoor occupational radiant exposure and available ambient solar radiation across different teaching classifications and schools relative to the daily occupational solar ultraviolet radiation (HICNIRP) protection standard of 30J/m(2). Self-reported daily sun exposure habits (n=480) and personal radiant exposures were monitored using calibrated polysulphone dosimeters (n=474) in 57 teaching staff from 6 different schools located in tropical north and southern Queensland. Daily radiant exposure patterns among teaching groups were compared to the ambient UV-Index. Personal sun exposures were stratified among teaching classifications, school location, school ownership (government vs non-government), and type (primary vs secondary). Median daily radiant exposures were 15J/m(2) and 5J/m(2)HICNIRP for schools located in northern and southern Queensland respectively. Of the 474 analyzed dosimeter-days, 23.0% were found to exceed the solar radiation protection standard, with the highest prevalence found among physical education teachers (57.4% dosimeter-days), followed by teacher aides (22.6% dosimeter-days) and classroom teachers (18.1% dosimeter-days). In Queensland, peak outdoor exposure times of teaching staff correspond with periods of extreme UV-Index. The daily occupational HICNIRP radiant exposure standard was exceeded in all schools and in all teaching classifications.

Minimum exposure limits and measured relationships between the vitamin D, erythema and international commission on non-ionizing radiation protection solar ultraviolet.

The International Commission on Non-Ionizing Radiation Protection (ICNIRP) has established guidelines for exposure to ultraviolet radiation in outdoor occupational settings. Spectrally weighted ICNIRP ultraviolet exposures received by the skin or eye in an 8 h period are limited to 30 J m(-2). In this study, the time required to reach the ICNIRP exposure limit was measured daily in 10 min intervals upon a horizontal plane at a subtropical Australian latitude over a full year and compared with the effective Vitamin D dose received to one-quarter of the available skin surface area for all six Fitzpatrick skin types. The comparison of measured solar ultraviolet exposures for the full range of sky conditions in the 2009 measurement period, including a major September continental dust event, show a clear relationship between the weighted ICNIRP and the effective vitamin D dose. Our results show that the horizontal plane ICNIRP ultraviolet exposure may be used under these conditions to provide minimum guidelines for the healthy moderation of vitamin D, scalable to each of the six Fitzpatrick skin types.

Determination of the usage of shade structures via a dosimetry technique.

A measurement system is described that allows an objective review and evaluation of the amount of use by different population groups of provided shade structures. It employs the comparison of the erythemal UV exposure measured with dosimeters to either the vertex or forehead to that in full sun. The technique has been developed using three shade structures and found to provide a linear relationship with an R(2) of 0.99 between the exposure ratio and the time spent in the shade for the solar zenith angle range of 19-53° and for both low- and high-cloud levels. It provides an objective determination of the amount of shade use by population groups that have set periods of time outdoors.

Basal and squamous cell carcinoma risks for golfers: an assessment of the influence of tee time for latitudes in the Northern and Southern hemispheres.

This study investigates the influence of tee time to determine the relative basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) risk for weekly single round competition golfers located in the Northern and Southern latitude ranges between 25°, 35°, 45° and 55°. A comparative risk methodology, employing annual erythemally effective ultraviolet (UVE) exposure calculations was used to determine BCC and SCC risk factors for golfers using a regular weekly tee time. Relative risk was found to be proportional to golf tee time with mid morning tee times generally presenting the greatest risk in each latitude range. The greatest contribution toward the risk of developing basal and squamous cell carcinoma was found to occur for golfers beginning weekly rounds mid to late morning, with specific risk factors of 1.47 (BCC) and 1.98 (SCC) in the Northern hemisphere compared with similar maximum risk factors of 1.51 (BCC) and 2.08 (SCC) in the Southern hemisphere occurring at comparable morning tee times. Differences in annual UVE exposure between the golfer and non-golfer were the largest determinant of BCC and SCC risk. Generally, these risks were found to decrease with lower latitude although contribution toward overall risk was influenced strongly by the global time zone of each studied golf course site.

Measurements of the upper body ultraviolet exposure to golfers: non-melanoma skin cancer risk, and the potential benefits of exposure to sunlight.

BACKGROUND: Geographically, Queensland presents an extreme ultraviolet exposure climate to members of the public engaged in outdoor recreational activity. The risk of developing a skin cancer or an eye disease as a result of incidental exposure to naturally occurring ultraviolet radiation in the outdoor environment is proportionately high in a Queensland population compared with fair-skinned population groups residing in comparable Northern Hemisphere latitudes. In contrast to these risks, elderly members of this high growth population group have been reported to be vitamin D deficient. The risks and potential benefits of exposure to sunlight in southern Queensland are assessed in this study with respect to recreational golfing. This sport is a popular recreational activity for the Queensland population and must be played during daylight hours. METHODS: The erythemal and vitamin D effective ultraviolet exposure measured to the forearm, upper back and vertex are presented for individuals playing golf under various atmospheric conditions in a 7-month period extending from summer to winter. RESULTS: Mean summertime exposures were measured in the 2008 study period as be 1.4, 2.2 and 3.2 standard erythema doses (SED) at forearm, upper back and vertex sites, respectively, compared with respective wintertime forearm, upper back and vertex exposures of 0.2, 0.3 and 0.5 SED, where summertime exposures were recorded in the mean solar zenith angle (SZA) ranges of 56-59 degrees and wintertime exposures were recorded in the mean SZA range 74-83 degrees. Vitamin D(3) effective exposures were determined to vary from between 225, 325 and 475 J/m(2) during summer and 48, 59 and 88 J/m(2) during winter for the respective forearm, upper back and vertex body sites measured in the above mean SZA ranges. CONCLUSION: Exposures to ambient ultraviolet during winter on the golf course between 15:00 and 17:30 hours could be beneficial for office workers for the production of vitamin D. Optimizing exposure periods to late afternoon in the winter months and taking adequate sun protection measures in the summer months are important strategies that golfers can utilize for long-term preventative health.

Measurements of the anatomical distribution of erythemal ultraviolet: a study comparing exposure distribution to the site incidence of solar keratoses, basal cell carcinoma and squamous cell carcinoma.

Measurements of anatomical UV exposure distribution were made using miniaturized polysulfone dosimeters over a four year period between 2005 and 2008 in Toowoomba, Australia (28 degrees S, 152 degrees E). Anatomical UV exposures were expressed relative to the horizontal plane ambient UV. The UV exposures were compared with existing data detailing the anatomical distribution of basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and solar keratoses (SK). Surface UV exposures to unprotected skin surfaces have been presented for each of the face, neck, arm, hand and leg assessing a total of 1453 body sites (2491 measurements). Measured exposures are presented for the human facial region to a resolution of 5 mm. The median anatomical UV expressed relative to the horizontal plane ambient UV for each of the face, neck, forearm, hand and leg regions of the body varied from 26%, 23%, 13%, 30% and 12% respectively in the 0 degrees-30 degrees SZA range; 39%, 36%, 17%, 35% and 23% in the 30 degrees-50 degrees SZA range; and 48%, 59%, 41%, 42% and 47% in the 50 degrees-80 degrees SZA range. Detailed positions of UV exposure measured over the face, neck, arm, hand and leg were more closely related to NMSC incidence data for the face and upper limbs. Further analysis with existing facial BCC and SK density data did not however show a direct relationship with the measured UV exposures highlighting the importance of other factors influencing the causation and localisation of facial NMSC.

Ultraviolet exposures in different playground settings: a cohort study of measurements performed in a school population.

BACKGROUND: Solar erythemally effective ultraviolet (UVE) measured on the face, neck, arms, hands and legs of a cohort of school children was investigated with respect to student movement about a school environment located in Southern Queensland. METHODS: A total of 147 erythemally effective solar UV exposures were measured using polysulphone film dosimeters. Measurements were performed on exposed skin surfaces during school hours between 08:30 and 15:05 hours for the period 5 February to 4 June 2008. RESULTS: Median seasonal UVE exposures varied between 0.4 and 2.7 standard erythema doses (SED) for school students observing the normal school routine between winter and summer, respectively. These exposures increased significantly for school activities scheduled primarily outdoors, reaching a maximum of 50 SED recorded to a vertex site measured during a school swimming carnival. CONCLUSION: The excessive erythemal UV exposures measured in this research have the potential to significantly contribute to the later development of melanoma and non melanoma skin cancers caused by acute and chronic cumulative exposure to solar UV in Queensland school environments. The research provides data on personal UV exposures measured in a school population engaged in daily school activities.

Variation of the enhanced biologically damaging solar UV due to clouds.

The variation of the biologically damaging solar UV (UVBE) enhanced by clouds above that of clear sky UVBE has been investigated. This was undertaken for summer through to winter for SZA of 5 to 60 degrees employing an integrated automatic cloud and spectral UV measurement system that recorded the solar UV spectra and the sky images at five minute intervals. The UVBE calculated with action spectra with higher relative effectiveness in the UVA produced the lower percentage of cloud enhanced cases. The DNA UVBE provided the highest percentage of cloud enhanced cases compared to the total number of UV scans with 2.2% cloud enhanced cases. As a comparison, the plant and fish melanoma UVBE provided the lowest percentage of cloud enhanced cases with 0.6 to 0.8% cloud enhanced cases. For the cases of cloud enhanced UVBE, the average ratio of the measured UVBE to calculated cloud free UVBE for the photokeratitis, cataracts, plant, generalized plant damage and fish melanoma action spectra was 1.21 to 1.25. In comparison, the highest value of 1.4 was for the DNA action spectrum.