Review on Nonoccupational Personal Solar UV Exposure Measurements

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

Detector-Based Calibration Method for High-Accuracy Solar UV Measurements

A novel method for calibrating the absolute responsivity of solar UV spectroradiometers has been developed and tested. The method is based on calibrated filter radiometers constructed from a detector, a precision aperture, a band-pass filter and devices for temperature stabilization. The filter radiometers utilize a trap detector with very low reflectance. The filter and the detector can therefore be characterized separately. As an example the detector-based calibration is compared at 312 nm wavelength with lamp-based calibration by measuring the irradiance of a deuterium lamp with both the filter radiometer and the lamp-calibrated spectroradiometer. The agreement between the results is at the level of 1%, well within the estimated uncertainties of both methods.     

New Entrance Optics for Solar Spectral UV Measurements

The investigation of the impact of solar UV radiation on the biosphere requires spectral measurements of solar UV radiation of high accuracy. However, the accuracy of current measurements is limited, and this can partly be attributed to the entrance optics of the instruments used for these examinations. The angular response of spectro-radiometers measuring spectral global UV irradiance should be given by the cosine of the incidence angle. In-tercomparison campaigns have shown that deviations from this ideal cosine response lead to uncertainties in solar measurements of more than 10%. Here we present recently developed entrance optics that reduce these uncertainties to ±4% in the UV. The new entrance optics have been characterized with respect to their angular response, transmission, weather durability, fluorescence and dependence of the angular response on wavelength and polarization. Solar spectroradiometric measurements carried out with the new optics were compared with simultaneously performed measurements of a second spectroradiometer that was equipped with a conventional diffuser. The deviations of up to 12% between both systems are quantitatively explained to within 3%.     

Occupational UV Exposure of Environmental Agents in Valencia,Spain

Excessive exposure to ultraviolet radiation (UVR) is considered the most important environmental risk factor in the development of melanoma and skin cancer. Outdoor workers are among those with the highest risk from exposure to solar UVR, as their daily activities constantly expose them to this radiation source. A study was carried out in Valencia, Spain, in summer 2012 and involved a group of 11 workers for a period of six 2‐day recordings. Sensitive spore‐film filter‐type personal dosimeters (VioSpor) were used to measure erythemal UVR received by environmental agents in the course of their daily work. Median 2‐day UV exposure was 6.2 standard erythema dose (SED), with 1 SED defined as effective 100 J m^?2 when weighted with the Commission Internationale de L′Eclairage's (CIE) erythemal response function. These workers were found to receive a median of 8.3% total daily ambient ultraviolet erythemal radiation. Comparison with the occupational UV exposure limit showed that the subjects had received an erythemal UV dose in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.     

Solar UV Exposure of Seafarers along Subtropical and Tropical Shipping Routes

Seafarers working on decks of vessels at low latitudes are exposed to extremely high solar UV radiation. Their risk of developing skin cancer may be enhanced. Solar erythemal UV irradiance and exposure were measured for the first time on merchant vessels going along typical international routes at low latitudes. The measurements taken at horizontal incidence on the observation deck, and on different parts of the seaman (head, shoulder, chest and back) doing typical outdoor work show the highest portion (40–80% of horizontal exposure) incident on the head. 2 years of measurements of solar UV and VIS/NIR irradiance taken on the mast top of the Research Vessel METEOR were added to the data base. Radiative transfer model calculations were performed along all the routes with satellite‐based input data of ozone and aerosol for clear sky health‐effective radiation including vitamin D3 (VD3). Measured data show extremely high noontime UV index values up to 19 with clear sky, and up to 22 due to cloud scattering. Eight hours erythemal exposure values are more than double of typical midlatitude summer values. Based on the results, an algorithm is presented to derive a seafarer's personal erythemal exposure according to his/her personal record of sea service.     

Occupational Exposure Modelling With EASE

Abstract

This article presents a validation exercise performed from eight practical case studies on EASE (version 2.0), a knowledge-based system allowing to estimate the workplace exposure to chemicals. Our results show that EASE represents a valuable simulation tool in occupational hygiene. However, it requires to be refined and extended to more realistic and precise situations to be easily used in practice.     

Occupational Exposure to Solar UVB and Seasonal Monitoring of Serum Levels of 25-hydroxy Vitamin D3: A Case–Control Study

To characterize the relationship between occupational sun exposure and seasonal variations in serum 25-OH-D3, four consecutive measurements of 25-OH-D3, one per season, were taken in 122 outdoor and 104 indoor Israeli workers. Continuous UVB measurements, taken in Beer Sheva, Israel, provided the average daily standard erythema dose (SED) of ambient solar UVB. The average daily exposure of the outdoor and indoor workers to solar UVB was 4.4 ± 1.6 h (4.0–37.6 SED) and 0.9 ± 0.5 h (0.6–8.2 SED), respectively. At each season mean 25-OH-D3 were significantly higher among outdoor workers than among indoor workers. Mean 25-OH-D3 increased significantly from spring to autumn in both gender and occupational groups. Adjusting for confounders, high (>median) 25-OH-D3 among males was significantly associated with occupational sun exposure in the autumn (odds ratio [OR] 4.31; 95% confidence interval [CI] 1.4–13.3), and among females in the spring (OR 3.35; 95% CI 1.53–7.32). Among this working population optimal vitamin D status (≥30 ng mL⁻¹) was approached only in summer by males working either outdoor or indoor. In the rest of the year 25-OH-D3 ranged between ≥20.0 and 29.0 ng mL⁻¹. Monitoring 25-OH-D3 may disclose undesirable vitamin D status following reduced sun exposure for skin cancer prevention among outdoor workers.     

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.     

职业性铅接触对血压影响的研究

对１１８名铅接触工人及１０８名对照组工人的血压研究发现，在血铅为４４．２６μｇ／ｄＬ时，铅接触工人的收缩压显著高于对照组，分组研究发现，收缩压在级组剂量－反应关系趋势，在血铅３０．２０μｇ／ｄＬ，收缩压显著高于对照组，多元逐步回归分析发现，在控制一些其他影响血压的因素后，铅接触工人的血铅水平与收缩压和舒张压均有剂量－反应关系。     

Occupational Exposure to Pesticides in Finland

Abstract

The annual use of pesticides in Finland counted as ingredients has been around 2000 tons from the seventies. Herbicides, which are mostly used in agriculture, are almost 80% of the total use of pesticides. Amount of workers occupationally exposed to pesticides is about 170000. Farmers are the largest group among exposed persons. Their number is around 50000 but their exposure periods last only for few days every summer. In greenhouses, around 20000, and in forestry, nearly 1500 workers are exposed to pesticides with more regular and longer lasting exposure than that of farmers. In the Finnish Register of Occupational Diseases, 79 cases caused by pesticides were reported during the years 1972-1991. Most of the cases were from greenhouses, agriculture and forestry. Typical symptoms in reports were toxic eczema or acute symptoms. Occupational exposure of workers to pesticides in Finland has been mainly studied by the Kuopio Regional Institute of Occupational Health since 1978. Exposure levels have been evaluated by occupational hygienic measurements and biological monitoring. Field studies done in agriculture, forestry and greenhouses revealed that exposure of the workers in most cases is at low level. Skin contamination is the main factor of exposure. Therefore, the use of personal protective clothing is essential for minimising exposure. Situations, where risk for exposure is high, are the dilution of formulation before spraying, preparation of equipment on fields, and contamination of skin when the work is started immediately after applications on fields and in greenhouses.     

Photostability of Cosmetic UV Filters on Mammalian Skin Under UV Exposure

Previous studies showed that the common UV filter substances benzophenone‐3 (BP–3), butyl methoxydibenzoylmethane (BM–DBM), octocrylene (OCR), ethylhexyl methoxycinnamate (EHMC), ethylhexyl salicylate (EHS) and ethylhexyl triazone (EHT) were able to react with amino side chains of different proteins in vitro. To transfer the results to mammalian skin conditions, sunscreen products were applied on both prepared fresh porcine skin and glass plates, followed by UV irradiation and the determination of depletion of the respective UV filters. Significantly lower recoveries of the UV filters extracted from skin samples than from glass plates indicated the additional reaction of the UV filters with skin constituents, when proteins will be the most important reactants. Among the products tested, BP‐3 showed the greatest differences in recoveries between glass and skin samples of about 13% and 24% after 2 and 4 h of irradiation, respectively, followed by EHS > BM‐DBM > OCR > EHMC > EHT. The obtained results raise the question, whether the common in vitro evaluations of sunscreens, using inert substrate materials like roughened quartz or polymethyl methacrylate (PMMA) plates are really suitable to fully replace in vivo methods, as they cannot include skin‐typical reactions.     

Solar UV dose patterns in Italy

Since 1992 solar ultraviolet (UV) spectral irradiance (290-325 nm) has been measured at two Italian stations of Rome (urban site) and Ispra (semirural site) using Brewer spectrophotometry. The data collected under all sky conditions, are compared with the output of a sophisticated radiative transfer model (System for Transfer of Atmospheric Radiation--STAR model). The STAR multiple scattering scheme is able to cope with all physical processes relevant to the UV transfer through the atmosphere. The experience so far acquired indicates that, in spite of the unavoidable uncertainties in the input parameters (ozone, aerosol, surface albedo, pressure, temperature, relative humidity, cloud cover), measured and computed clear sky iradiances are in reasonable agreement. The STAR model is applied to build up the solar UV geographic patterns in Italy: the daily dose in the range 290-325 nm is computed at about 70 sites where a thorough and homogeneous climatology is available. For each month the concept of an idealized "standard day" is introduced and the surface distribution of solar UV field determined. The map of solar UV patterns for Italy, available for the first time, meets the study requirements in the field of skin and eye epidemiology, as well as in other investigations dealing with the impact of UV on the biosphere. The results are interpreted in terms of atmospheric and meteorological parameters modulating UV radiation reaching the ground.     

Measurement of UVA Exposure to Solar Radiation

Exposure to solar UVA (320–400 nm) radiation can damage DNA and lead to skin disorders. Conventional dosim-etry using a single piece of polysulfone or diglycol carbonate (CR-39) cannot provide accurate measurement of the biologically effective irradiance for erythema for the UVA waveband. A package employing four dosimeters (polysulfone, nalidixic acid, 8-methoxypsoralen and phe-nothiazine) has been shown to be effective for use as a spectrum evaluator for evaluating the UVA source spectrum. In Brisbane, on a horizontal position, the spectrum evaluator requires about 5 min exposure in summer and about 20 min in winter. This amounts to about 10 mJ cm-² of erythemal UV radiation.     

UV Radiation Exposure of Outdoor Workers in Antarctica

The Antarctic region is a place of increasing interest. A growing number of personnel are working outdoors in extreme environmental conditions. They receive significant exposure to solar ultraviolet radiation (UVR) and are thereby at increased risk of adverse consequences. The aim of this study was to evaluate the UVR dose received by the outdoor workers at the Bulgarian Antarctic Base. Ten Caucasian healthy subjects, 8 males and 2 females with a mean age of 38 years (29–51) were enrolled. Of them, 5 were scientists and 5 were logistic workers. We measured the accumulated daily dose of UVR assessed by standard erythemal dose (SED) in the two groups. All subjects wore personal dosimeters located near the face—he only noncovered skin area. The dosimeters were factory calibrated for use in the Antarctic region. No statistical difference (P = 0.441) could be revealed between the SEDs in the two groups. The maximum UVR dose detected in a single day was 67.9 SEDs, and the highest cumulative dose was 548.03 SEDs. Study results are showing extreme measurements of UVR received by the members of the expeditions. We suggest meticulous UV protection for outdoor workers.     

职业性铅接触与各生物接触参数间的关系评估

在对蓄电池厂１００名铅接触者的健康监护中，各项生物监测按规定的质量控制要求进行，并研究了其间的剂量效应关系，结果发现，空气中铅尘，铅烟低于最高容许多浓度，接触者的血铅，尿铅和ＦＥＰ呈非常显著相关（Ｐ〈０．０１），其中血铅有较好地定量反映接触铅工人体内的铅负荷，并提出了血铅的可接受水平。     

Solar UV irradiation and dermal photoaging.

The skin is increasingly exposed to ambient UV-irradiation thus increasing risks for photooxidative damage with long-term detrimental effects like photoaging, characterized by wrinkles, loss of skin tone and resilience. Photoaged skin displays alterations in the cellular component and extracellular matrix with accumulation of disorganized elastin and its microfibrillar component fibrillin in the deep dermis and a severe loss of interstitial collagens, the major structural proteins of the dermal connective tissue. The unifying pathogenic agents for these changes are UV-generated reactive oxygen species (ROS) which deplete and damage non-enzymatic and enzymatic antioxidant defense systems of the skin. As well as causing permanent genetic changes, ROS activate cytoplasmic signal transduction pathways in resident fibroblasts that are related to growth, differentiation, senescence and connective tissue degradation. This review focuses on the role of UV-induced ROS in the photodamage of the skin resulting in clinical and biochemical characteristics of photoaging. In addition, the relationship of photoaging to intrinsic aging of the skin will be briefly discussed. A decrease in the overall ROS load by efficient sunscreens or other protective agents may represent promising strategies to prevent or at least minimize ROS-induced photoaging.     

Erythemal UV Radiation on Days with Low UV Index Values—an Analysis of Data from the German Solar UV Monitoring Network over a Ten‐year Period

According to the World Health Organization and partner organizations, no protection against ultraviolet (UV) radiation is required on days with “low” values (i.e., values <3) of the Global Solar Ultraviolet Index (UVI). Erythemal irradiance (E_er) data of such days were analyzed to evaluate this claim. Measurements from 9 stations of the German solar UV monitoring network from 2007 to 2016 yielded 14,431 daily E_er time series of low UVI days. Erythemal doses for certain fixed time intervals—acquired from measurements on horizontal planes—were compared with the average minimal erythemal dose (MED) of skin phototype II. Doses from days with rounded UVI values of 0 were insufficient to induce erythema and even on days with rounded UVI values of 1 doses exceeding 1 MED of skin type II could only be acquired under very specific circumstances of prolonged exposure. Conversely, sun exposure on days with rounded UVI values of 2 can indeed provide doses sufficient to induce erythema in skin type II after two hours around noon. In conclusion, our analyses do not support the claim of harmlessness currently associated with the entire low UVI exposure category in public guidance on interpretation of the UVI.     

Solar UV irradiation conditions on the surface of Mars

The UV radiation environment on planetary surfaces and within atmospheres is of importance in a wide range of scientific disciplines. Solar UV radiation is a driving force of chemical and organic evolution and serves also as a constraint in biological evolution. In this work we modeled the transmission of present and early solar UV radiation from 200 to 400 nm through the present-day and early (3.5 Gyr ago) Martian atmosphere for a variety of possible cases, including dust loading, observed and modeled O3 concentrations. The UV stress on microorganisms and/or molecules essential for life was estimated by using DNA damaging effects (specifically bacteriophage T7 killing and uracil dimerization) for various irradiation conditions on the present and ancient Martian surface. Our study suggests that the UV irradiance on the early Martian surface 3.5 Gyr ago may have been comparable with that of present-day Earth, and though the current Martian UV environment is still quite severe from a biological viewpoint, we show that substantial protection can still be afforded under dust and ice.     

Third-Generation Solar Cells: Toxicity and Risk of Exposure

Solar energy is considered clean energy, and its use is predicted to increase in the near future. Most installed units today are crystalline solar cells, but the field is in constant development, and when the first dye sensitized solar cell was published by Grätzel and O'Reagan a new, third-generation, solar power was born. Highly toxic metals are used to produce the photovoltaic units today, and with the predicted increase in solar cell installation, the human health hazards of these panels could become an issue. Additionally, many of these materials are used in their nanoform, which is associated with an additional risk. In this article, we discuss the technology behind the third-generation solar cells with its valuable use of nanotechnology as well as the possible health hazard when such nanomaterials are used in solar power units. We will show that the main exposure will occur either during the development and production phases or at the end-of-life stage of the solar cells, where toxic material can leach into landfills, and subsequently into the environment and impact the ecosystem directly, or humans indirectly through edible plants or drinking water.