Ambient Ultraviolet Radiation Research Articles

Abstract 843: The burden of Merkel cell carcinoma attributable to immunosuppression, ultraviolet radiation, and Merkel cell polyomavirus in the United States

Abstract Background: Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer. No published study has estimated the contribution of the major potentially modifiable risk factors, such as immunosuppression, ultraviolet radiation (UVR) and infection with Merkel cell polyomavirus (MCPyV), to the burden of MCC in the US. We estimated the population attributable fractions (PAFs) for MCC associated with immunosuppression (HIV and organ transplantation), MCPyV, and UVR in the US during 2001-2020. Methods: We calculated PAFs for immunosuppression and UVR using the formula: prevalence in cases (Pc)*[(Relative risk, RR-1)/RR]. The proportion of MCC cases among organ recipients and people with HIV (Pc) were derived from US cancer registries in the HIV/AIDS Cancer Match Study, Transplant Cancer Match Study, and the Surveillance Epidemiology and End Results (SEER) Program data. To approximate the RRs, we calculated standardized incidence ratios (SIRs) comparing MCC incidence in people with HIV and organ recipients to the general population. We merged SEER data on MCC cases by county with data on ambient UVR levels in order to create population quintiles of UVR exposure. Since only non-Hispanic White individuals showed elevated IRRs for increased ambient UVR exposure, we estimated the PAF of UVR by calculating incidence rate ratios (IRR ≈ RR) comparing MCC incidence in non-Hispanic White individuals to all other races/ethnicities (at any UVR level) as the reference; here, Pc was the proportion of non-Hispanic White patients in each quintile. To estimate the PAF of MCPyV, we meta-analyzed US studies reporting on MCPyV prevalence in MCC tissues (here PAF ≈ Pc). Results: Over the study period (2001-2020), 40,571 MCCs were diagnosed in the US. Compared to the general population, organ recipients had 13 times higher (SIR=12.7, CI: 11.3-14.2) and people with HIV had three times higher (SIR=2.78, CI: 2.01-3.75) risk of MCC. Due to the rarity of these exposures (HIV Pc = 0.4%; Transplant Pc = 1.9%), only 0.2% of MCC cases were attributable to HIV and 1.7% were attributable to organ transplantation. Compared with people in other racial/ethnic groups, the IRRs of non-Hispanic White individuals at the various levels of ambient UVR for MCC arising on the head and neck ranged from 4.24 to 5.03 and for other primary sites ranged from 2.81 to 3.36. After combining the PAFs for these sites, the overall PAF for UVR was 65.8%. Meta-analyzing 20 studies with 984 MCC cases combined, we found that 66.1% (CI: 58.0-72.2%) of MCCs were attributable to MCPyV. Conclusions: While a small proportion of MCCs were due to immunosuppression from HIV infection and organ transplantation, UVR and MCPyV played a major role in MCC burden. Future research is required to assess the combined impact of these risk factors on MCC incidence. Citation Format: Jacob T. Tribble, Karena Volesky-Avellaneda, Qianlai Luo, Michael R. Sargen, Isaac Brownell, Elizabeth K. Cahoon, Meredith Shiels, Ruth Pfeiffer, Adrianne Moreno, Brenda Y. Hernandez, Eric Engels. The burden of Merkel cell carcinoma attributable to immunosuppression, ultraviolet radiation, and Merkel cell polyomavirus in the United States [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 843.

Effects of ambient UVB light on Pacific oyster Crassostrea gigas mantle tissue based on multivariate data

Ambient ultraviolet radiation (UVB) from solar and artificial light presents serious environmental risks to aquatic ecosystems. The Pacific oyster, Crassostrea gigas, perceives changes in the external environment primarily through its mantle tissue, which contains many nerve fibers and tentacles. Changes within the mantles can typically illustrate the injury of ambient UVB. In this study, a comprehensive analysis of phenotypic, behavioral, and physiological changes demonstrated that extreme UVB radiation (10 W/m²) directly suppressed the behavioral activities of C. gigas. Conversely, under ambient UVB radiation (5 W/m²), various physiological processes exhibited significant alterations in C. gigas, despite the behavior remaining relatively unaffected. Using mathematical model analysis, the integrated analysis of the full-length transcriptome, proteome, and metabolome showed that ambient UVB significantly affected the metabolic processes (saccharide, lipid, and protein metabolism) and cellular biology processes (autophagy, apoptosis, oxidative stress) of the C. gigas mantle. Subsequently, using Procrustes analysis and Pearson correlation analysis, the association between multi-omics data and physiological changes, as well as their biomarkers, revealed the effect of UVB on three crucial biological processes: activation of autophagy signaling (key factors: Ca2+, LC3B, BECN1, caspase-7), response to oxidative stress (reactive oxygen species, heat shock 70, cytochrome c oxidase), and recalibration of energy metabolism (saccharide, succinic acid, translation initiation factor IF-2). These findings offer a fresh perspective on the integration of multi-data from non-model animals in ambient UVB risk assessment.

Estimating population-level 25-hydroxyvitamin D concentrations in Australia and New Zealand using the sun exposure (SUNEX) microsimulation model

Exposure to ultraviolet (UV) radiation from the sun has both harms and benefits for human health. The best-known benefit of sun exposure is the generation of vitamin D within the skin and the best-known harm is malignant skin cancer. Australia and New Zealand have very high ambient UV radiation, resulting in high rates of skin cancer incidence and mortality, yet there is an appreciable prevalence of vitamin D deficiency (defined as blood 25-hydroxyvitamin D (25(OH)D) < 50 nmol/L) in both populations. The purpose of this study was to create a microsimulation model to replicate population 25(OH)D concentrations of people living in Australia and New Zealand, thus enabling the effect of different population-wide interventions to be estimated. We used large population datasets containing data on sun behaviours and socio-demographic variables, and environmental data on UV radiation, ozone, and solar zenith angle. Latitude, weather and time of day were accounted for. We simulated the conversion of daily UV radiation to a standard vitamin D dose (SDD) (100 J/m2 vitamin D-weighted UV) and monthly accumulation of SDD to 25(OH)D concentration. The model was calibrated to match the seasonal prevalence of vitamin D deficiency. This report describes the Sun Exposure (SUNEX) microsimulation model, its development, data inputs and calibration against population prevalence of vitamin D deficiency.

Ambient UV radiation is associated with cutaneous angiosarcoma incidence in the United States, 1992 to 2020

Ambient UV radiation is associated with cutaneous angiosarcoma incidence in the United States, 1992 to 2020

Ambient ultraviolet radiation and ocular melanoma incidence in the United States, 2000-2019.

Ocular melanoma is a rare, but deadly cancer. This large cancer registry study examines the associations between solar ultraviolet radiation (UVR) and incidence of different anatomical sites of ocular melanoma by sex, age, laterality, and race and ethnicity. Incidence data were derived from 21 cancer registries in the US for the years 2000-2019. Satellite-based UVR estimates were linked to county of residence at diagnosis. Incidence rate ratios (IRRs) and 95% confidence intervals (CIs) were calculated for UVR quartiles using Poisson models. UVR was not associated with total ocular melanoma (N = 18,089) comparing Q4 versus Q1 (IRR = 0.98; 95%CI:0.94,1.03; p-trend = 0.07) or conjunctival melanoma (IRR = 0.99; 95%CI:0.82,1.19; p-trend = 0.81). However, in analyses of continuous UVR (per 10 mW/m2), risks were reduced for total ocular melanoma (IRR = 0.97; 95% CI: 0.96, 0.99). Incidence was increased for ciliary body/iris melanoma in the highest UVR quartile (IRR = 1.63; 95%CI:1.43,1.87; p-trend < 0.0001) and remained increased in non-Hispanic Whiteindividuals only. Incidence was reduced for choroidal melanoma in the highest UVR quartile (IRR = 0.86; 95%CI:0.82,0.91; p-trend < 0.0001). UVR may be associated with increased risk of ciliary body/iris melanoma. Reduced risk of choroidal melanoma may be due to higher diffuse UVR exposure to posterior ocular sites in locations at higher latitudes. Our results support and expand previous findings of associations of UVR using various surrogates on ocular melanoma risk and serve as a starting point for understanding the differences in the relationship between UVR and specific anatomical sites.

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 (&lt;40°), the risk of UV overexposure clearly decreases.

Modelling the dispersion of infectious salmon anemia virus from Atlantic salmon farms in the Quoddy Region of New Brunswick, Canada and Maine, USA

Pathogen dispersal from infected aquaculture sites into the surrounding ocean poses risks of infection to wild and farmed species, but is difficult to predict. This study aimed to build a framework using an ocean circulation and a particle tracking model in conjunction with a dynamic infection model and a virus inactivation model to simulate the dispersal of the infectious salmon anemia virus (ISAV) from Atlantic salmon farms. Simulated particles were released from hypothetically infected farms and advected by modelled currents. Inactivation of viral cohorts by ambient ultraviolet radiation and natural microbial communities was simulated during advection. Simulations showed that ISAV concentration varied spatiotemporally with the progression of the outbreak, current speed and direction, tidal elevation amplitude, and environmental decay. Connectivity among aquaculture sites varied in relation to seaway distances, though simulations showed that connectivity can also be asymmetrical between farm sites. Sensitivity analyses showed that the dispersal of ISAV was moderately sensitive to uncertainty associated with the viral decay model, highlighting the importance of obtaining accurate estimates of inactivation rates of ISAV. This framework provides an approach to simulate waterborne viral transmission that considers the biology and epidemic features of significance for pathogens and the dynamic conditions of the ocean.

LIFETIME AMBIENT ULTRAVIOLET RADIATION EXPOSURE AND INCIDENCE OF AGE-RELATED MACULAR DEGENERATION.

To investigate the link between lifelong exposure to ultraviolet radiation (UVR) and the development of age-related macular degeneration (AMD). The Alienor study is a prospective population-based cohort involving 963 residents of Bordeaux, France, older than 73 years. A subset of 614 participants for advanced AMD and 422 participants for early AMD were included in the analysis. The participants' residential history combined with UVR estimates from the EuroSun satellite were used to estimate the amount of ambient UVR they have been exposed to over their lifetime. Age-related macular degeneration was classified from retinal fundus photographs and spectral domain optical coherence tomography at 2 to 3 years intervals over the 2006 to 2017 period. Associations between cumulative exposure to ultraviolet A, ultraviolet B, and total (total UV) and the incidence of early and advanced AMD were estimated using multivariate Cox models. Intermediate quartiles of total UV, ultraviolet A, and ultraviolet B exposures were associated with a higher risk for incident early AMD (Hazard Ratio [HR] =2.01 [95% confidence interval [CI] = 1.27-3.13], HR = 2.20 [95% CI = 1.38-3.50], HR = 1.79 [95% CI = 1.13-2.80], respectively) as compared with the lower quartile. However, this risk did not further increase in the highest quartiles of exposure. None of the three types of UVR exposure was significantly associated with incident advanced AMD. Despite an increased risk with intermediate compared with low UVR exposure, our study cannot confirm a dose-response relationship of UVR exposure with early AMD onset.

Changing Trends in the Global Burden of Cataract Over the Past 30 Years: Retrospective Data Analysis of the Global Burden of Disease Study 2019.

Cataracts now account for the largest proportion of the global burden of blindness and vision loss. Understanding the changing trends in the global burden of cataracts over the past 30 years and the next 15 years is of clear significance for the prevention and control of cataracts in key populations. As far as we know, research on the future burden of cataracts is lacking. This study aims to assess the global burden of cataracts over the past 30 years by using age-period-cohort modeling and to estimate trends in the next 15 years. Data were obtained from the Global Burden of Disease Study 2019, the United Nations Development Programme, and the WHO (World Health Organization) Global Health Observatory data repository. The assessment of trends and disparities in the number and rate of disability-adjusted life years (DALYs) for cataracts from 1990 to 2019 was conducted. The association between the age-standardized DALY rate (ASDR) and the socio-demographic index (SDI), human development index (HDI), national levels of particulate matter <2.5 μm in diameter (PM2.5), and ambient ultraviolet radiation (UVR) was determined using linear regression analysis. Additionally, we used the Nordpred (Harald Fekjær and Bjørn Møller) age-period-cohort model to predict the cataract burden from 2020 to 2034. Globally, the number of DALYs due to cataract increased from 3,492,604 (95% uncertainty interval [UI] 2,481,846-4,719,629) in 1990 to 6,676,281 (95% UI 4,761,210-9,006,193) in 2019. The ASDRs due to cataract decreased from 93.17 (95% UI 66.14-125.32) in 1990 to 82.94 (95% UI 59.06-111.75) in 2019, with an average annual percentage change of -0.37 (95% CI -0.44 to -0.3; P<.001). Age, female sex, air pollution, smoking, high fasting plasma glucose levels, and a high body mass index were risk factors for the burden of cataracts. SDI and HDI were negatively correlated with ASDRs of cataracts, while PM2.5 and UVR were positively associated with them. Higher DALY rates were also associated with lower SDI (R2=0.1939; P<.001), lower HDI (R2=0.2828; P<.001), national PM2.5 concentration (R2=0.1874; P<.001), and ambient UVR levels (R2=0.2354; P<.001). The prediction model suggested that the number of DALYs due to cataract will continue to rise globally, while the cataract DALY rate will continue to decrease. While the ASDR of cataracts has decreased, there has been a notable increase in the number of DALYs over the past 30 years. Projections suggest that the global burden of cataracts will continue to rise over the next 15 years. To address this challenge, appropriate prevention and treatment policies must be implemented.

A cohort analysis of residential radon exposure and melanoma incidence in Switzerland

Radon is a radioactive noble gas found in Earth's crust. It accumulates in buildings, and accounts for approximately half the ionizing radiation dose received by humans. The skin is considerably exposed to ionizing radiation from radon. We aimed to evaluate the association between residential radon exposure and melanoma and squamous cell carcinoma incidence.The study included 1.3 million adults (20 years and older) from the Swiss National Cohort who were residents of the cantons of Vaud, Neuchâtel, Valais, Geneva, Fribourg, and Ticino at the study baseline (December 04, 2000). Cases of primary tumours of skin (melanoma and squamous cell carcinoma) were identified using data from cantonal cancer registries. Long-term residential radon and ambient solar ultraviolet radiation exposures were assigned to each individual's address at baseline. Cox proportional hazard models with age as time scale, adjusted for canton, socioeconomic position, demographic data available in the census, and outdoor occupation were applied. Total and age specific effects were calculated, in the full population and in non-movers, and potential effect modifiers were tested.In total 4937 incident cases of melanoma occurred during an average 8.9 years of follow-up. Across all ages, no increased risk of malignant melanoma or squamous cell carcinoma incidence in relation to residential radon was found. An association was only observed for melanoma incidence in the youngest age group of 20–29 year olds (1.68 [95% CI: 1.29, 2.19] 100 Bq/m3 radon). This association was mainly in women, and in those with low socio-economic position.Residential radon exposure might be a relevant risk factor for melanoma, especially for young adults. However, the results must be interpreted with caution as this finding is based on a relatively small number of melanoma cases. Accumulation of radon is preventable, and measures to reduce exposure and communicate the risks remain important to convey to the public.

Ultraviolet sun exposure and sun protection behaviors in outdoor rock climbers

BackgroundOverexposure to sunlight and sunburn are the main preventable causes of skin cancer. Outdoor sports are associated with significant levels of sunlight exposure.AimsWe sought to quantify the sun radiation exposure received by outdoor rock climbers and assess their sun exposure habits, sun protection behaviors, attitudes, and knowledge regarding skin cancer.MethodsFrom April to June 2021, outdoor rock climbers contacted via email completed an online validated self-reported questionnaire on sun related habits, behaviors, attitudes and knowledge. As a pilot trial, ten participants wore a personal dosimeter during two outdoor climbing weekends in May and November 2021. Ambient ultraviolet radiation (UVR) was also recorded.ResultsA total of 217 outdoor rock climbers (103 women), mean age 36.8 ± 8.8 years (range 20–70 years) and median climbing practice per week of 8 h (IQR 7.5) were studied. Two in three (65.9%) participants reported at least one sunburn event during the previous rock climbing season. Of the survey respondents, 49.3% reported using sunscreen with SPF ≥ 15, 47% wore sunglasses, and 14.3% indicated they reapplied sunscreen every two hours. The median personal UVR dose measured during the two outdoor climbing weekends analyzed was 5.2 (IQR 1.8) and 8.8 (IQR 1.1) standard erythemal doses, respectively.ConclusionsThe high rates of sunburn, the elevated personal UVR measured and the clearly insufficient sun protection practices followed during rock climbing together with unsatisfactory attitudes towards tanning reveal the need to develop explicit sun protection campaigns and educational strategies to reduce the risk of skin cancer among the athletes studied.Graphical abstract

Linkages between COVID-19, solar UV radiation, and the Montreal Protocol

There are several connections between coronavirus disease 2019 (COVID-19), solar UV radiation, and the Montreal Protocol. Exposure to ambient solar UV radiation inactivates SARS-CoV-2, the virus responsible for COVID-19. An action spectrum describing the wavelength dependence of the inactivation of SARS-CoV-2 by UV and visible radiation has recently been published. In contrast to action spectra that have been assumed in the past for estimating the effect of UV radiation on SARS-CoV-2, the new action spectrum has a large sensitivity in the UV-A (315–400 nm) range. If this “UV-A tail” is correct, solar UV radiation could be much more efficient in inactivating the virus responsible for COVID-19 than previously thought. Furthermore, the sensitivity of inactivation rates to the total column ozone would be reduced because ozone absorbs only a small amount of UV-A radiation. Using solar simulators, the times for inactivating SARS-CoV-2 have been determined by several groups; however, many measurements are affected by poorly defined experimental setups. The most reliable data suggest that 90% of viral particles embedded in saliva are inactivated within ~ 7 min by solar radiation for a solar zenith angle (SZA) of 16.5° and within ~ 13 min for a SZA of 63.4°. Slightly longer inactivation times were found for aerosolised virus particles. These times can become considerably longer during cloudy conditions or if virus particles are shielded from solar radiation. Many publications have provided evidence of an inverse relationship between ambient solar UV radiation and the incidence or severity of COVID-19, but the reasons for these negative correlations have not been unambiguously identified and could also be explained by confounders, such as ambient temperature, humidity, visible radiation, daylength, temporal changes in risk and disease management, and the proximity of people to other people. Meta-analyses of observational studies indicate inverse associations between serum 25-hydroxy vitamin D (25(OH)D) concentration and the risk of SARS-CoV-2 positivity or severity of COVID-19, although the quality of these studies is largely low. Mendelian randomisation studies have not found statistically significant evidence of a causal effect of 25(OH)D concentration on COVID-19 susceptibility or severity, but a potential link between vitamin D status and disease severity cannot be excluded as some randomised trials suggest that vitamin D supplementation is beneficial for people admitted to a hospital. Several studies indicate significant positive associations between air pollution and COVID-19 incidence and fatality rates. Conversely, well-established cohort studies indicate no association between long-term exposure to air pollution and infection with SARS-CoV-2. By limiting increases in UV radiation, the Montreal Protocol has also suppressed the inactivation rates of pathogens exposed to UV radiation. However, there is insufficient evidence to conclude that the expected larger inactivation rates without the Montreal Protocol would have had tangible consequences on the progress of the COVID-19 pandemic.Graphical abstract

Vitamin D and Sun Exposure: A Community Survey in Australia.

Sun exposure carries both harms and benefits. Exposing the skin to the sun is the main modifiable cause of skin cancers, which exert a considerable health and economic burden in Australia. The most well-established benefit of exposure to ultraviolet (UV) radiation is vitamin D production. Australia has the highest incidence of skin cancer in the world but, despite the high ambient UV radiation, approximately one quarter of the population is estimated to be vitamin D deficient. Balancing the risks and benefits is challenging and requires effective communication. We sought to provide a snapshot of public knowledge and attitudes regarding sun exposure and vitamin D and to examine the associations between these factors and sun protective behaviors. In 2020 we administered an online survey; 4824 participants with self-reported fair or medium skin color were included in this analysis. Only 25% and 34% of participants were able to identify the amount of time outdoors needed to maintain adequate vitamin D status in summer and winter, respectively and 25% were concerned that sunscreen use inhibits vitamin D synthesis. This lack of knowledge was associated with suboptimal sun protection practices. Public education is warranted to prevent over-exposure, while supporting natural vitamin D production.

MXene quantum dots/perovskite heterostructure enabling highly specific ultraviolet detection for skin prevention

•TQD/CNO photodetectors featuring high UV light selectivity •Photon-generated charge carrier enhancement by TQDs •1,100% increase in spectral responsivity compared with CNO NS photodetector •A visible-blind UV monitoring system for skin and plant protection is demonstrated Two-dimensional (2D) perovskite-based optoelectronic devices have broad application prospects because of the ultrafast and ultrasensitive detection in particular wavelength ranges. However, the low light absorption generated by atomically thin perovskite nanosheet (NS) layers has limited their practical applications. In this study, Ti3C2Tx quantum dots (TQDs) were used to enhance charge carriers of 2D perovskite Ca2Nb3O10 (CNO) NSs to improve the performance of the TQD-modified 2D perovskite CNO NS photodetector, as shown by the 1,100% increase in spectral responsivity compared with that of the reference photodetector without TQDs. The flexible TQD/CNO photodetector was integrated with a data collector to simulate a wearable visible-blind UV monitoring system for skin and plant protection. And the ambient UV radiation information in various weather can be then trained and recognized by an artificial neural network for alert users. This work demonstrates the potential applications of TQD/CNO in UV-related wearable healthcare and control systems. Two-dimensional (2D) perovskite-based optoelectronic devices have broad application prospects because of the ultrafast and ultrasensitive detection in particular wavelength ranges. However, the low light absorption generated by atomically thin perovskite nanosheet (NS) layers has limited their practical applications. In this study, Ti3C2Tx quantum dots (TQDs) were used to enhance charge carriers of 2D perovskite Ca2Nb3O10 (CNO) NSs to improve the performance of the TQD-modified 2D perovskite CNO NS photodetector, as shown by the 1,100% increase in spectral responsivity compared with that of the reference photodetector without TQDs. The flexible TQD/CNO photodetector was integrated with a data collector to simulate a wearable visible-blind UV monitoring system for skin and plant protection. And the ambient UV radiation information in various weather can be then trained and recognized by an artificial neural network for alert users. This work demonstrates the potential applications of TQD/CNO in UV-related wearable healthcare and control systems.

Use of antihypertensive drugs and risk of cutaneous melanoma: a nationwide nested case-control study.

Most antihypertensives can induce dermal photosensitivity, which may increase melanoma risk. However, corroborating evidence is limited. We examined the associations between use of antihypertensives and melanoma risk. A nationwide nested case-control study was conducted using data from the Cancer Registry of Norway, the National Registry and the Norwegian Prescription Database in 2004-15. Ten controls were randomly selected for each melanoma case, matched on sex and birth year. The study included 12 048 cases and 117 895 controls. We estimated rate ratios (RRs) with 95% confidence intervals (CIs). All analyses were adjusted for ambient ultraviolet radiation (UVR). We additionally performed active comparator analyses, and sensitivity analyses by only including new users, distinguishing between exclusive and mixed users, allowing for different latency periods, and subgroup analyses by melanoma subtype and clinical stage. Compared with non-use, we observed a slightly increased melanoma risk in users of diuretics (RR 1.08, CI 1.01-1.15), calcium-channel blockers (RR 1.10, CI 1.04-1.18) and drugs affecting the renin-angiotensin system (RR 1.10, CI 1.04-1.16), but not for beta blockers (RR 0.97, CI 0.92-1.03). We found no heterogeneity of associations by melanoma subtype or clinical stage and no dose-response relationship between the cumulative defined daily doses (DDDs) and melanoma. No interaction was found between cumulative DDDs and ambient UVR. Weak associations, with lack of a dose-response relationship and lack of interactions with ambient UVR, in the DDD analysis in this nationwide study do not support a causal relationship between antihypertensives and melanoma risk.

Letter to the Editor: Does Ambient Ultraviolet Radiation Affect Psoriasis Severity

Letter to the Editor: Does Ambient Ultraviolet Radiation Affect Psoriasis Severity

Vitamin D Supplementation and the Incidence of Cataract Surgery in Older Australian Adults

Observational studies suggest that higher serum 25-hydroxy vitamin D (25(OH)D) concentration may be associated with lower risk of cataract. However, no randomized controlled trials have assessed the effect of vitamin D supplementation on the incidence of cataract. We aimed to assess whether vitamin D supplementation reduces the incidence of cataract surgery. We conducted an ancillary study of the D-Health Trial, a randomized, double-masked, placebo-controlled trial of monthly vitamin D conducted from 2014 through 2020 within the Australian general population. We invited 421 207 men and women 60 to 84 years of age to participate; including an additional 1896 volunteers, 40 824 expressed interest. Those with hypercalcemia, hyperparathyroidism, kidney stones, osteomalacia, or sarcoidosis or those who were taking more than 500 international units (IU) supplemental vitamin D per day were excluded. A total of 21 315 were randomized, and 1390 participants did not fulfil the eligibility criteria for this analysis (linked data available, no cataract within first 6 months), leaving 19 925 included. The median follow-up was 5 years. Participants took 60 000 IU of vitamin D3 (n= 10 662) or placebo (n= 10 653) orally once per month for a maximum of 5 years. The primary outcome for this analysis was the first surgical treatment for cataract, ascertained through linkage to universal health insurance records and hospital data. Among 19 925 participants eligible for this analysis (mean age, 69.3 years; 46% women) 3668 participants (18.4%) underwent cataract surgery during follow-up (vitamin D: n= 1841 [18.5%]; placebo: n= 1827 [18.3%] ). The incidence of cataract surgery was similar between the two groups (incidence rate, 41.6 and 41.1 per 1000 person-years in the vitamin D and placebo groups, respectively; hazard ratio, 1.02; 95% confidence interval, 0.95-1.09). In prespecified subgroup analyses, the effect of vitamin D supplementation on the incidence of cataract surgery was not modified by age, sex, body mass index, predicted serum 25(OH)D concentration, or ambient ultraviolet radiation. Routinely supplementing older adults who live in an area with a low prevalence of vitamin D deficiency with high-dose vitamin D is unlikely to reduce the need for cataract surgery. Proprietary or commercial disclosure may be found after the references.

Ultraviolet radiation exposure in children, behavioral factors associated with measured doses and seasonality

BACKGROUND AND AIM Ultraviolet radiation (UVR) exposure is associated with both positive and adverse health, such as beneficial aspects of vitamin D and skin cancer, respectively. Childhood is a time of great variability for sun behaviours and increased sensitivity to UVR. However, the relationship between one’s received exposure and the level of ambient UVR is modified by activities. There is a need to document UVR exposure in relation to concurrent activities and sun protection behaviour for children and adolescents. While several studies have measured UVR exposure in children there has been no study conducted in Switzerland, where skin cancer incidence is one of the highest in Europe. METHODS UVR was measured in children aged 4-17 years (n=120) over 5 consecutive days using dosimeters worn on the chest. The dosimeter included an acceleration sensor, to identify periods during which it was worn. During measurement of UVR parents recorded children&amp;#x27;s activities in activity diaries. Measurements were related to reported activities and mean exposure (and spread) was assessed by activity type and season. RESULTS 4&amp;#x27;058 hours of exposure measurements was assessed. The measured mean cumulative daily exposure was 0.46 standard erythmal dose (SED) per participant. The largest contribution to the total cumulative dose came from activities that involved playing outdoors (83.4 SED), followed by walking (32.6 SED), and hiking (25.7 SED), which had the highest mean exposures. The mean exposures were higher during midday hours and at higher altitudes; however, did not evidently vary by season during the measurement period. CONCLUSIONS Children’s UVR in Switzerland varies considerably by activity and whereabouts, and is highest during midday and early afternoon hours, with only modest variation between seasons. While measured UVR intensities are similar for different outdoor activities, the largest contribution to received doses comes from playing outdoors. KEYWORDS Ultraviolet radiation exposure, children, exposure assessment

Effects of Algal Utilization of Dissolved Organic Phosphorus by Microcystis Aeruginosa on Its Adaptation Capability to Ambient Ultraviolet Radiation

Phosphorus (P) plays an important role in eutrophication and algal adaptation to environmental stresses; therefore, a better understanding of the impact of P is essential to control cyanobacterial bloom. In this study, Microcystis aeruginosa is treated with 5 h of ambient irradiation in the culture medium with different availabilities of dissolved organic P (DOP) and dissolved organic matter (DOM) to explore algal physiological responses. Compared to photosynthetically active radiation (PAR), ambient UV-A and UV-B radiation exerted oxidative stresses and has inhibitive effects on the growth and photosynthesis of M. aeruginosa. However, M. aeruginosa had a strong adaptation capability, and the negative effects of UV radiation can be alleviated with DOM addition in the DOP-rich medium. The adaptation of M. aeruginosa to UV radiation in the DOP-rich waters can be mainly achieved through hydrolysis of DOP and metabolism of dissolved inorganic P (DIP), and the DOP utilization behaviors of M. aeruginosa might greatly affect algal UV adaptation capability. In the DOP-rich medium without DOM, the great inactivation of algal alkaline phosphatase (APase) after UV radiation could result in worse affinity for DOP, slower DOP uptake and lower cellular P quota. Consequently, the P demand of M. aeruginosa could not be satisfied for UV adaptation processes, including decreasing UV-induced damages and promoting self-repair. However, DOM could act as an antioxidant and significantly decrease APase inactivation of UV-radiated M. aeruginosa. In the DOP-rich medium with DOM, DOP utilization by M.aeruginosa in the UV-A and UV-B treatments is promoted and algal demand for P is satisfied for its adaptation, such as enhanced production of photosynthetic pigments, increased superoxide dismutase (SOD) activity, recovery of photosynthetic efficiency, etc. Overall, our findings indicate the close relationship between algal DOP utilization and the adaptation to ambient UV radiation of typical cyanobacteria in DIP-limited and DOP-enriched natural waters.

Ambient ultraviolet radiation: A new factor affecting anaerobic fermentation of oat and subsequent methane emissions

To investigate the effect of ambient ultraviolet (UV) radiation on the Qinghai-Tibetan Plateau on anaerobic fermentation and subsequent methane emissions, oats grown under different ambient UV conditions (UV1, 100% ambient UV radiation; UV2, 50% ambient UV radiation) were fermented with molasses and Lactobacillus plantarum (LP) inoculant treatments. The UV2 treatment increased (P < 0.05) epiphytic bacterial counts and reduced (P < 0.05) the water-soluble carbohydrate contents of oat. Both the UV2 treatment and the LP inoculant substantially increased the abundance of Lactobacillus and inhibited detrimental microorganisms (enterobacteria and yeasts) during anaerobic fermentation, resulting in the absence of butyric acid. The UV2 treatment increased (P < 0.05) the acid detergent fiber contents after anaerobic fermentation and indirectly increased (P < 0.05) methane emissions by 8.52–14.69% during in vitro ruminal digestion. This study demonstrated that low ambient UV radiation during cultivation facilitated anaerobic fermentation and consequently enhanced subsequent methane emissions from the rumen.