Erythemal Ultraviolet Radiation Research Articles

Variability of solar UV radiation in the northern mountains of the Czech Republic, 2020–2021

Solar ultraviolet (UV) radiation has a crucial role in many atmospheric processes and a huge impact on living organisms. Its main positive effect is the synthesis of vitamin D, but it also causes problems such as sunburn, skin cancer or eye cataracts. In the mountains, high doses of UV frequently occur due to a specific combination of atmospheric and geographical factors such as a high ground reflection as a consequence of a large number of days with snow cover, or a lower concentration of atmospheric pollutants in comparison to lowland urban regions. This study used measurements of erythemal UV radiation from two high altitude areas: the Hrubý Jeseník Mountains (Vysoká hole meteorological station, 1 464 m a.s.l.) and the Giant Mountains (Luční bouda meteorological station, 1 413 m a.s.l.) in the Czech Republic, during 2020 and 2021. We evaluated the daily and monthly changes in erythemal dose and UV index. The maximum daily dose of 5.0 kJ.m-2 (8.9 of UV index) was measured on 28 June 2020 at Vysoká hole. The maximal UV index of 10.1 was observed at Luční bouda on 5 July 2020, while the maximum daily dose of 4.9 kJ.m-2 occurred on 14 June 2021. The main factors that caused changes in solar UV radiation were the amount of cloud cover as well as the total ozone column.

Estimation of the age of polyethylene microplastics collected from oceans: Application to the western North Pacific Ocean

The knowledge of microplastic (MP) age could aid the deduction of the origin and fate of a fragment carried by ocean currents over long time periods and distances. The present study developed a novel method to estimate the age of MPs (i.e., UV radiation exposure time) using the oxidation level of polyethylene (i.e., carbonyl index) from infrared spectrometry, ultraviolet erythemal radiation (UVER) data, and ambient seawater temperatures. Accelerated and outdoor exposure experiments were conducted to establish relationships among the temporally integrated UVER, ambient temperature, and carbonyl index. Thereafter, the age of MPs was computed, with Miyakojima Island serving as the reference location. The estimated ages of MPs collected from the western North Pacific Ocean ranged from 1 to 3 years, and those MPs from nearshore waters ranged from 0 to 5 years.

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

Erythemal UV radiation across Nigeria: where do we stand?

The deleterious effects of solar ultraviolet (UV) radiation on humans are of public health concern which demands constant global monitoring and intervention. This study analysed the latitudinal variations in mean daily and multi-year erythemal ultraviolet radiation (EUVR) across 7 states in Nigeria using satellite data from the Total Ozone Mapping Spectrophotometer (TOMS) and Ozone Mapping Instrument (OMI). The latitudes studied were 13° N, 8° N, 6° N and 4° N respectively, using 37 years of data obtained from phases: 1979–1988, 1989–1998, 1999–2008 and 2009–2020. The data obtained were statistically analysed using Ms Excel and MATLAB. The results of this study show that the mean daily EUVR at the selected latitudes ranges from 32.97 to 390 (mW/m2). The results show that Borno State located at latitude 13° N had the highest EUVR, while Rivers State recorded the least EUVR at latitude 4° N. Comparative analysis of all the locations studied indicates latitudinal and longitudinal variations because the eastern axis recorded higher values than its western counterpart on the same latitude. Box and whisker plots in this study summarized the latitudinal variance in the mean multi-year EUVR in each phase. Box and whisker plots from 2009–2020 showed that there was a drastic reduction in mean multi-year EUVR in this phase unlike in the other phases. The findings of this study when compared to the UV index show that the 37 years mean EUVR obtained across Nigeria ranged from 8–10 which is on the “very high” category. This study recommends the implementation of WHO suggestions in preventing the biological effects of solar UV radiation. Furthermore, the Nigerian government should curb ignorance among its citizens by heightening public awareness of the effects of EUVR.

Cumulative Erythemal Ultraviolet Radiation and Risk of Cancer in 3 Large US Prospective Cohorts.

Ultraviolet radiation (UVR) exposure is the major risk factor for melanoma. However, epidemiologic studies on UVR and noncutaneous cancers have reported inconsistent results, with some suggesting an inverse relationship potentially mediated by vitamin D. To address this, we examined 3 US prospective cohorts, the Health Professionals Follow-up Study (HPFS) (1986) and Nurses' Health Study (NHS) I and II (1976 and 1989), for associations between cumulative erythemal UVR and incident cancer risk, excluding nonmelanoma skin cancer. We used a validated spatiotemporal model to calculate erythemal UVR. Participants (47,714 men; 212,449 women) were stratified into quintiles by cumulative average erythemal UVR, using the first quintile as referent, for Cox proportional hazards regression analysis. In the multivariable-adjusted meta-analysis of all cohorts, compared with the lowest quintile, risk of any cancer was slightly increased across all other quintiles (highest quintile hazard ratio (HR)=1.04, 95% confidence interval (CI): 1.01, 1.07; P for heterogeneity= 0.41). All UVR quintiles were associated with similarly increased risk of any cancer excluding melanoma. As expected, erythemal UVR was positively associated with risk of melanoma (highest quintile HR=1.17, 95% CI: 1.04, 1.31; P for heterogeneity= 0.83). These findings suggest that elevated UVR is associated with increased risk of both melanoma and noncutaneous cancers.

UV Erythemal Radiation and Its Sensitivity to Changes in Total Column Ozone and Aerosols

UV Erythemal Radiation and Its Sensitivity to Changes in Total Column Ozone and Aerosols

Erythemal UV Radiation Across Nigeria: Where Do We Stand?

Erythemal UV Radiation Across Nigeria: Where Do We Stand?

Higher ultraviolet radiation during early life is associated with lower risk of childhood type 1 diabetes among boys

Population-level ecological studies show type 1 diabetes incidence is inversely correlated with ambient ultraviolet radiation (UVR) levels. We conducted a nested case–control study using administrative datasets to test this association at the individual level. Cases (n = 1819) were children born in Western Australia (WA) from 1980–2014, diagnosed with type 1 diabetes at ≤ 16 years. Controls (n = 27,259) were randomly selected from all live births in WA, matched to cases by sex and date of birth. Total ambient erythemal ultraviolet radiation (UVR) doses for each trimester of pregnancy and first year of life were estimated for each individual, using daily NASA satellite data that were date- and geographically-specific. Conditional logistic regression tested the association between UVR dose and case–control status. Type 1 diabetes risk was 42% lower in boys of mothers with third-trimester UVR dose in the highest (compared to the lowest) quartile (p = 0.04). Higher UVR in the first year of life was associated with lower type 1 diabetes risk among boys (p = 0.01). UVR dose was not associated with type 1 diabetes risk in girls. Higher UVR in late pregnancy and early life appear to interact with sex-specific factors to lower type 1 diabetes risk among boys in Western Australia.

Erythemal ultraviolet radiation exposure of high school rowers in Aotearoa/New Zealand.

Athletes who compete in outdoor sports can receive potentially harmful levels of solar ultraviolet radiation (UVR). Rowing is a popular outdoor sport that takes place during the peak UVR season. Using electronic dosimeters attached to the shoulder strap of the rower's uniform, this study aimed to quantify the real-time solar UVR exposure experienced by high school rowers during competition. We measured personal UVR exposure (PE) during the time spent on the water in order to compete in a single rowing-race (race-time), when rowing administrators are responsible for athletes' wellbeing. Data collection took place in Aotearoa (New Zealand) at Lake Ruataniwha (44.28°S, 170.07°E), during two consecutive rowing seasons (December-February 2018-19 and 2019-20). Analysis of dosimeter data generated from 56 race-times over five regattas revealed a median personal UVR exposure (PE) of 1.15 standard erythemal dose (SED), where 1 SED is defined as an effective radiant exposure of 100 Jm-2. Mean race-time was 46min. Over two-thirds of race-times (69.6%) exceeded the Australian Radiation Protection and Nuclear Safety Agency recommendation of 1 SED being considered safe for most people in a day. An exposure of 1.5-3.0 SED produces perceptible erythema for people with light coloured skin and the lower parameter of 1.5 SED was exceeded in 14 (25.0%) of the race-times. By regatta, the median SED/h ranged from 0.96-2.40 and the median percentage of total concurrent ambient UVR ranged from 17 to 31%. Our results indicate that rowing is a high UVR sport and that races outside of peak UVR times also warrant the use of sun protection even when the UVI<3. Given that acute and cumulative UVR exposure are recognised risk factors in the development of ocular diseases and skin cancers later in life, risk management guidelines for competitive school rowing will be incomplete until a long-term approach to well-being is considered and comprehensive sun protection measures adopted.

Ultraviolet radiation and age at natural menopause in a nationwide, prospective US cohort

BACKGROUND AND AIM: Ultraviolet radiation (UV) is essential for dermal conversion of vitamin D, which is suggested to support reproductive health. However, little is known about the association of UV exposure with reproductive aging. Thus, we aimed to examine the associations between long-term UV exposure and age at natural menopause in a large, nationwide, prospective cohort. METHODS: Women in the Nurses’ Health Study II, a nationwide prospective US cohort enrolled in 1989, were included if they were premenopausal at age 40 (N=105,631) and were followed through 2015 or self-reported menopause, whichever came first. Data on menopause, residence, and confounders were available every two years. Erythemal UV radiation from a high-resolution geospatial model was linked to the participants’ residential histories. Early-life UV was estimated using UV measures in the reported state of residence at birth, age 15, and age 30. We used time-varying Cox proportional hazard models to estimate the hazard ratio (HR) and 95% confidence intervals (CIs) for natural menopause, adjusting for potential confounders and predictors of menopause. RESULTS:A total of 63,801 women reported natural menopause during the 1,051,185 person-years of follow-up. We found weak associations with delayed menopause for long-term UV exposure after age 40 (adjusted HR comparing Q4 to Q1 of cumulative average UV: 0.96, 95% CI: 0.94, 0.99). There was a suggestive association between UV at age 30 with later onset of menopause (adjusted HR comparing Q4 to Q1: 0.97, 95% CI: 0.95, 1.00) but not with UV at birth or age 15. Similar weak associations were found when restricting the outcome to women who reported menopause between age 40 and 45. CONCLUSIONS:UV exposure in adulthood was weakly associated with later onset of menopause. Although consistent with previous findings on vitamin D intake and menopause in the same population, the associations are unlikely to be of clinical relevance. KEYWORDS: reproductive outcomes, long-term exposure, female

Ultraviolet radiation and age at natural menopause in a nationwide, prospective US cohort

BackgroundSolar ultraviolet radiation (UV) is a critical environmental factor for dermal conversion of vitamin D, which is suggested to support reproductive health. However, current epidemiological studies have reported conflicting results on the associations between vitamin D levels and ovarian reserve. Further, few studies have considered UV exposure and reproductive aging, which is closely related to declined ovarian reserve. ObjectivesWe sought to examine the associations of long-term UV exposure and age at natural menopause in a large, nationwide, prospective cohort. MethodsParticipants in the Nurses' Health Study II (NHS II) who were premenopausal at age 40 were included and followed through 2015. Erythemal UV radiation from a high-resolution geospatial model was linked to the participants’ residential histories. Early-life UV was estimated using the reported state of residence at birth, age 15, and age 30. We used time-varying Cox proportional hazards models to estimate the hazard ratio (HR) and 95% confidence intervals (CIs) for natural menopause, adjusting for potential confounders and predictors of menopause. ResultsA total of 63,801 women reported natural menopause across the 1,051,185 person-years of follow-up among 105,631 eligible participants. We found very modest associations with delayed menopause for long-term UV exposure (adjusted HR comparing highest to lowest quartile of cumulative average UV: 0.96, 95% CI: 0.94, 0.99). There was a suggestive inverse association between UV at age 30 with menopause (adjusted HR comparing highest to lowest quartile: 0.97, 95% CI: 0.95, 1.00) but not with UV at birth and age 15. ConclusionsSolar UV exposure in adulthood was modestly associated with later onset of menopause. Although consistent with previous findings on vitamin D intake and menopause in the same population, these weak associations found in this study may not be of clinical relevance.

Indoor tanning early in life is associated with increased risk of anxiety and depression later in life

Indoor tanning early in life is associated with increased risk of anxiety and depression later in life

Ultraviolet erythemal radiation in Central Chile: direct and indirect implication for public health

Ultraviolet erythemal radiation in Central Chile: direct and indirect implication for public health

283 Cumulative ultraviolet radiation exposure is associated with both increased melanoma and non-cutaneous cancer risk

Ultraviolet radiation (UVR) exposure is associated with increased risk of skin cancer. However, mixed evidence suggests a protective, inverse relationship between UVR and risk of certain non-cutaneous cancers, depending on temporality of exposure. To address this discrepancy, we examined three ongoing U.S. prospective cohort studies, the Health Professionals Follow-Up Study (HPFS) and Nurses’ Health Study (NHS) I and II, to identify associations between cumulative UV exposure and cancer risk. We used an established spatiotemporal exposure model to calculate cumulative time-varying average UV exposure, defined as average July noon-time erythemal UVR.

A Study of UVER in Santiago, Chile Based on Long-Term In Situ Measurements (Five Years) and Empirical Modelling

Ultraviolet radiation is a highly energetic component of the solar spectrum that needs to be monitored because is harmful to life on Earth, especially in areas where the ozone layer has been depleted, like Chile. This work is the first to address the long-term (five-year) behaviour of ultraviolet erythemal radiation (UVER) in Santiago, Chile (33.5° S, 70.7° W, 500 m) using in situ measurements and empirical modelling. Observations indicate that to alert the people on the risks of UVER overexposure, it is necessary to use, in addition to the currently available UV index (UVI), three more erythema indices: standard erythemal doses (SEDs), minimum erythemal doses (MEDs), and sun exposure time (tery). The combination of UVI, SEDs, MEDs, and tery shows that in Santiago, individuals with skin types III and IV are exposed to harmfully high UVER doses for 46% of the time that UVI indicates is safe. Empirical models predicted hourly and daily values UVER in Santiago with great accuracy and can be applied to other Chilean urban areas with similar climate. This research inspires future advances in reconstructing large datasets to analyse the UVER in Central Chile, its trends, and its changes.

Record-Breaking Increases in Arctic Solar Ultraviolet Radiation Caused by Exceptionally Large Ozone Depletion in 2020.

Measurements of solar ultraviolet radiation (UVR) performed between January and June 2020 at 10 Arctic and subarctic locations are compared with historical observations. Differences between 2020 and prior years are also assessed with total ozone column and UVR data from satellites. Erythemal (sunburning) UVR is quantified with the UV Index (UVI) derived from these measurements. UVI data show unprecedently large anomalies, occurring mostly between early March and mid‐April 2020. For several days, UVIs observed in 2020 exceeded measurements of previous years by up to 140%. Historical means were surpassed by more than six standard deviations at several locations in the Arctic. In northern Canada, the average UVI for March was about 75% larger than usual. UVIs in April 2020 were elevated on average by about 25% at all sites. However, absolute anomalies remained below 3.0 UVI units because the enhancements occurred during times when the solar elevation was still low.

Use of linked administrative and laboratory data to confirm that serum 25(OH)D levels in pregnant women can be predicted from satellite estimates of ultraviolet radiation.

Serum 25 hydroxyvitamin D [25(OH)D] levels of pregnant women have been linked to various health outcomes in their offspring. Satellite-derived ultraviolet radiation (UVR) data have been used as a proxy for 25(OH)D levels, as individual-level cohort studies are time-consuming, costly and only feasible for common outcomes. Data on 25(OH)D levels from a public laboratory database were linked to data from the Western Australian Midwives' Notification System and daily erythemal UVR dose from NASA satellites. Regression analysis was used to identify the time period prior to venesection where daily UVR dose best predicted 25(OH)D levels. A predictive model was used to validate the use of daily UVR dose as a proxy for personal sun exposure during pregnancy. Data from 19173 pregnancies in women aged 18-43 years in Western Australia were included. The daily UVR dose averaged over the 90 days before venesection was the strongest UVR predictor of 25(OH)D level (a 5% increase per 1000 J m-2; equal to 3.3 nmol L-1 at the median of 66 nmol L-1). Ethnicity was the strongest predictor of 25(OH)D levels (21% lower in non-Caucasian vs Caucasian: equal to 7.2 nmol L-1 difference). Other significant predictors were gestation, age, year, parity, socio-economic status, remoteness, medical conditions and season. NASA-derived erythemal UVR dose in the 90 days prior to venesection is a significant predictor of 25(OH)D levels in pregnant women. Linked administrative data can be used to investigate associations between UVR during pregnancy and health outcomes in offspring.

A One-Month Monitoring of Exposure to Solar UV Radiation of a Group of Construction Workers in Tuscany

Solar radiation exposure at work is a relevant heath risk in the construction sector. Our objective was to monitor for a full month the individual solar ultraviolet radiation (UVR) exposure of a group of three construction workers active in Siena (latitude = 43°19′ N), a town in Tuscany (Italy). We used personal electronic dosimeters “X-2012-10” (Gigahertz, Turkenfeld, Germany) to register the UV irradiance in the UVA and UVB/C regions separately and we consulted a specific database to retrieve the corresponding ambient erythemal UVR dose (cloud-free conditions). In spring, construction workers from central Italy received a quite variable UVR dose, between 0.9 standard erythemal doses (SED) and 15.6 SED/day, 5.7 on average. Considering the proportion with respect to the potential environmental exposure, personal exposure resulted between 2.7% and 31.2% of the ambient erythemal dose, with a mean value of 12.5%. Cumulatively, the three construction workers received in one working month a UVR dose of more than 120 SED. In a year, we estimated that a construction worker from Tuscany region is exposed to about 750 SED. This data demonstrates that construction workers in Italy are exposed to extremely high levels of solar UVR, with a relevant risk of developing adverse health effects related to the potential accumulation of UVR-induced damage in susceptible biological tissues, such as the skin and the eyes.

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.

西藏晴天太阳红斑紫外线观测研究

西藏晴天太阳红斑紫外线观测研究