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.

The Simulated Ocular and Whole-Body Distribution of Natural Sunlight to Kiteboarders: A High-Risk Case of UVR Exposure for Athletes Utilizing Water Surfaces in Sport.

Kiteboarding is an aquatic sporting discipline that has not yet been considered in the literature to date in terms of solar ultraviolet radiation (UVR) measurement. Kiteboarders need to look upward and are placed obliquely relative to the horizon when towed behind an overhead kite over a reflective water surface. This research defines the typical body surface orientation of a kiteboarder in motion through video vector analysis and demonstrates the potential risk to ocular and skin surface damage through practical measurement of solar UVR using a manikin model. Video analysis of 51 kiteboarders was made to construct skeletal wireframes showing the surface orientation of the leg, thigh, spine, humerus, lower arm and head of a typical kiteboarder. Solar UVR dosimeter measurements made using a manikin model demonstrate that the vertex and anterior surfaces of the knee, lower leg and lower humerus received 89%, 90%, 80% and 63% of the available ambient UVR, respectively, for a typical kiteboarder who is tilted back more than 15° from vertical while in motion. Ocular (periorbital) exposures ranged from 56% to 68% of ambient. These new findings show that the anterior skin surfaces of kiteboarders and the eye are at elevated risk of solar UVR damage.

Assessment of Biologically Effective Solar Ultraviolet Exposures for Court Staff and Competitors During a Major Australian Tennis Tournament.

Sport is an integral and enduring part of many societies, such as Australia. Participation in outdoor sports, such as tennis, comes with a very real risk of dangerous solar ultraviolet exposure which can result in erythema (sunburn), serious conditions such as skin cancer, including melanoma, and eye conditions such as cataracts and pterygium. This study remotely assesses the effective ultraviolet exposures in response to the increased sun safety awareness at a major summertime tennis tournament in Australia. The assessment only uses publicly accessible data and information. It was found that tournament organizers have effectively adopted sun-safe protocols into the uniform policy that the court officials (judges and ball kids) are mandated to follow. The combination of sun-participant geometry and the photoprotection provided by uniforms significantly reduced the ambient ultraviolet exposure, which was recorded to be as high as 9.9 SED h-1 , to just 1.0 and 0.5 SED h-1 for ball kids and judges, respectively, compared to up to 2.0 SED h-1 for players. Even though caution is needed against complacency with sun safety, with the need for the court officials and the players to still apply sunscreen, the court officials provided persistent visual role modeling of sun-safe behaviors.

Seasonal variations in the subsurface ultraviolet-B on an inshore Pacific coral reef ecosystem.

Fringing coral reefs provide a unique opportunity to study shallow aquatic ecosystems. A fringing coral reef system located in close proximity to a developed region was considered in this study. In such an environment, the rate of decay of dissolved organic matter is high and the penetration of higher energy ultraviolet-B (UVB) extends a greater influence on species diversity, particularly upon shallow benthic communities. Results from a 9 month subsurface UVB exposure measurement campaign performed at a site located on the southern Queensland coast (Hervey Bay, 25°S) are presented in this research. For this, a novel dosimetric technique was utilized to measure long-term subsurface UVB exposures. The resultant data set includes exposure measurements made during the significant La Niña event of late 2010 which resulted in unprecedented high sea surface temperatures and severe flooding across eastern Australia, impacting upon the lagoon regions of the Great Barrier Reef and Queensland's southern estuaries, including the study site. The influence of season, diurnal tidal variation, cloud cover and solar zenith angle were analyzed over the campaign period. Mean minimum daylight water depth was found to be the most significant factor influencing subsurface UVB.

Characterisation and evaluation of a miniaturised polyphenylene oxide dosimeter for ultraviolet exposures.

Dosimeters are used in measuring received ultraviolet (UV) radiation by humans and plants. Previously dosimeters 3.0cm×3.0cm weighing 0.6g, using poly(2,6-dimethyl-1,4-phenylene oxide) (PPO)(1) as the photoactive material have been used. A smaller 1.0cm×1.5cm flexible PPO dosimeter weighing 0.05g has been developed and characterised in this research. Laboratory and field studies show that the miniaturised dosimeter measures comparative results to the larger dosimeters for cosine response, dark reaction and dose response. The smaller, flexible dosimeters are also more applicable for use on curved surfaces and have less impact on the orientation of plant leaves due to their decreased mass. This research has also shown that miniaturised PPO dosimeters can be successfully employed on plant and human subjects to accurately determine biologically active UV distributions. The miniaturised PPO dosimeters allow for more measurements over an exposed area and the PPO film allows for measurements to be made for periods longer than 1day. The combination of smaller size and longevity of the photoactive material allows for more flexibility in future UV field research resulting in an increase in the potential number of environments where UV dosimeters can be deployed.

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.

Empirical evaluation of global vitamin D effective ultraviolet irradiances under cloudy conditions for a subtropical southern hemisphere site.

This paper evaluates the global vitamin D effective UV (UV(vitd)) irradiances under cloudy conditions at a subtropical, southern hemisphere site. The UV(vitd) irradiances were analyzed on a horizontal plane and sampled at 5-min intervals over 18 months so that a wide range of parameters including cloud conditions, solar zenith angles (SZA) and ozone levels were taken into account. Cloud modification factors were determined from the influence of clouds on the global broadband solar radiation, and these were applied to the cloud-free vitamin D effective UV irradiance to evaluate the UV(vitd) irradiances on a horizontal plane for cloudy conditions. For vitamin D effective UV irradiance, cloud modification factors were found to range from 0.9 to 1.0 for no cloud and 0.4 to 0.5 for 8 octa of cloud cover. SZA played a minimal role in this variation. A comparison of the measured and calculated UV(vitd) irradiances for the 2004 data set in the range of SZA of 70 degrees or less provided an R(2) value of 0.90. The output of the model was compared to data measured during the first 6 months of 2005 for an SZA of 70 degrees or less and provided an R(2) value of approximately 0.82.

Usage of the polyphenylene oxide dosimeter to measure annual solar erythemal exposures.

Poly (2,6-dimethyl-1,4-phenylene oxide) (PPO) film is a useful dosimetric tool for measuring solar UV in underwater and terrestrial environments. However, little is known about how the response of PPO changes with fluctuations in atmospheric ozone and also to seasonal variations. To resolve this issue this article presents a series of long-term in-air solar erythemal response measurements made over a year from 2007 to 2008 with PPO. This data showed that the PPO dose response varies with modulations of the solar spectrum resulting from changes in season and atmospheric ozone. From this, it was recommended that PPO only be calibrated in the season in which it is to be used at the same time as measurements were being made in the field. Extended solar UV measurements made by PPO with a neutral density filter (NDF) based on polyethylene are also detailed. These measurements showed that the lifetime of PPO could be extended by 5 days before saturation. As the dynamic range for PPO is known to be 5 days during summer at a sub-tropical location, the advantage of using the NDF is that half the number of dosimeters is needed to be fabricated and measured before and after exposure.

Solar UV exposures measured simultaneously to all arbitrarily oriented leaves on a plant.

The possible ramifications of climate change include the influence it has upon the amount of cloud cover in the atmosphere. Clouds cause significant variation in the solar UV radiation reaching the earth's surface and in turn the amount incident on ecosystems. The consequences of changes in solar UV radiation delivered to ecosystems due to climate change may be significant and should be investigated. Plants are an integral part of the world wide ecological balance, and research has shown they are affected by variations in solar UV radiation. Therefore research into the influence of solar UV radiation on plants is of particular significance. However, this requires a means of obtaining detailed information on the solar UV radiation received by plants. This research describes a newly developed dosimetric technique employed to gather information on solar UV radiation incident to the leaves of plants in combination with the measurement of spectral irradiances in order to provide an accurate method of collecting detailed information on the solar UV radiation affecting the canopy and lower leaf layers of individual plants. Variations in the measurements take into account the inclination and orientation of each leaf investigated, as well as the influence of shading by other leaves in the plant canopy.

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.

Solar ultraviolet protection provided by human head hair.

The solar erythemal UV irradiances through human hair and the protection from UV provided by human head hair have been investigated for a solar zenith angle (SZA) range of 17-51 degrees for the conditions of a head upright in full sun, a head upright in shade and a head in full sun tilted toward the sun. The two hair lengths investigated were 49.1 +/- 7.1 mm for the short type and 109.5 +/- 5.5 mm for the long type. For the head upright in full sun, the irradiances through the hair ranged from 0.75 to 1.4 SED h(-1) for SZA <25 degrees and <0.6 SED h(-1) in shade. The ultraviolet protection factor (UPF) ranged from approximately 5 to 17 in full sun, with the UPF increasing with higher SZA. The longer hair provided a lower UPF than the shorter hair and for the head oriented toward the sun, there was a marginally lower UPF than for the upright head. This research shows that the UV exposure limits to the scalp through hair can be exceeded within short timeframes and provides important information to assist employers to comply with Workplace Health and Safety legislation.

Evaluation of a high exposure solar UV dosimeter for underwater use.

Solar ultraviolet radiation (UV) is known to have a significant effect upon the marine ecosystem. This has been documented by many previous studies using a variety of measurement methods in aquatic environments such as oceans, streams and lakes. Evidence gathered from these investigations has shown that UVB radiation (280-320 nm) can negatively affect numerous aquatic life forms, while UVA radiation (320-400 nm) can both damage and possibly even repair certain types of underwater life. Chemical dosimeters such as polysulphone have been tested to record underwater UV exposures and in turn quantify the relationship between water column depth and dissolved organic carbon levels to the distribution of biologically damaging UV underwater. However, these studies have only been able to intercept UV exposures over relatively short time intervals. This paper reports on the evaluation of a high exposure UV dosimeter for underwater use. The UV dosimeter was fabricated from poly 2,6-dimethyl-1,4-phenylene oxide (PPO) film. This paper presents the dose response, cosine response, exposure additivity and watermarking effect relating to the PPO dosimeter as measured in a controlled underwater environment and will also detail the overnight dark reaction and UVA and visible radiation response of the PPO dosimeter, which can be used for error correction to improve the reliability of the UV data measured by the PPO dosimeters. These results show that this dosimeter has the potential for long-term underwater UV exposure measurements.

Increased DNA damage sensitivity of Cornelia de Lange syndrome cells: evidence for impaired recombinational repair.

Cornelia de Lange syndrome (CdLS) is a rare dominantly inherited multisystem disorder affecting both physical and mental development. Heterozygous mutations in the NIPBL gene were found in about half of CdLS cases. Scc2, the fungal ortholog of the NIPBL gene product, is essential for establishing sister chromatid cohesion. In yeast, the absence of cohesion leads to chromosome mis-segregation and defective repair of DNA double-strand breaks. To evaluate possible DNA repair defects in CdLS cells, we characterized the cellular responses to DNA-damaging agents. We show that cells derived from CdLS patients, both with and without detectable NIPBL mutations, have an increased sensitivity for mitomycin C (MMC). Exposure of CdLS fibroblast and B-lymphoblastoid cells to MMC leads to enhanced cell killing and reduced proliferation and, in the case of primary fibroblasts, an increased number of chromosomal aberrations. After X-ray exposure increased numbers of chromosomal aberrations were also detected, but only in cells irradiated in the G(2)-phase of the cell cycle when repair of double-strand breaks is dependent on the establishment of sister chromatid cohesion. Repair at the G(1) stage is not affected in CdLS cells. Our studies indicate that CdLS cells have a reduced capacity to tolerate DNA damage, presumably as a result of reduced DNA repair through homologous recombination.