María-Antonia Serrano

Solar UV exposure in construction workers in Valencia, Spain

Exposure to ultraviolet radiation (UVR) has long been recognized as the most important environmental risk factor for melanoma and skin cancer. Outdoor workers are among the groups most at risk from exposure to solar UVR in their daily activities. Sensitive spore-film filter-type personal dosimeters (VioSpor) were used to measure the biologically effective UVR received by construction workers in the course of their daily work. The study took place in Valencia, Spain, in July 2010 and involved a group of eight workers for a period of 5 days. The median UV exposure was 6.11 standard erythema dose (SED) per day, with 1 SED defined as effective 100 J/m2 when weighted with the Commission Internationale de L’Eeclairage erythemal response function. These workers were found to receive a median of 13.9% of total daily ambient ultraviolet erythemal radiation (UVER). Comparison with the occupational UVR exposure limit showed that the subjects had received UVER exposure in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.

Ultraviolet exposure for different outdoor sports in Valencia, Spain.

The purpose of this study is to quantify ultraviolet (UV) exposure of several groups of amateur athletes in their training or recreational schedules.

Erythemal ultraviolet solar radiation doses received by young skiers

Children are a special group since epidemiological evidence indicates that excessive exposure to sunlight at an early age increases the risk of skin cancer in later life. The purpose of this study is to quantify childrens UV exposure when skiing, using dosimeters (VioSpor) placed on the shoulders of 10 participants. The children received a median daily Standard Erythema Dose of 2.1 within a range of 4.9-0.71, this being approximately 35% of the calculated 24 h ambient UV radiation on the horizontal plane. According to the results obtained, young skiers are exposed to UV radiation that can potentially cause skin damage and erythema and increase the risk of skin cancer in the course of a lifetime. These findings emphasise the need for adequate protective measures against solar radiation when skiing. The results also suggest that sun-protection campaigns should be undertaken aimed at children engaged in outdoor sports, including winter activities.

Solar ultraviolet doses and vitamin D in a northern mid-latitude

Solar ultraviolet (UV) radiation is one of the most important factors in the development of skin cancer in human, solar erythema and skin aging. Nevertheless, numerous studies have shown the benefits of UV solar radiation in moderate doses, such as the reduction of blood pressure and mental health, treatment of various diseases, and the synthesis of vitamin D in the skin. This paper analyses data from solar ultraviolet erythemal (UVER) irradiance in W/m2 measured in a northern mid-latitude as Valencia (Spain) for the period 2003-2010. To estimate effective solar UV radiation in the production of vitamin D (UVD) we used the relationship proposed by McKenzie et al. (2009). It was obtained for one month for each season the minimum exposure time needed around solar noon and at 9 UTC and 15 UTC (Coordinated Universal Time) to obtain the recommended daily dose of 1000IU. Also, it has been calculated time for erythema induction around solar noon for the same months. The median UVER daily dose during the summer months was 4000J/m2day, and 700J/m2day in winter. With regard to UVD, the median UVD daily dose in summer season was 7700J/m2day, and in winter it was 1000J/m2day. Around noon in January it takes more than two hours of solar exposure to obtain the recommended daily dose of vitamin D, whereas the rest of the year range between 7min on July and 31min on October. For the same months around noon, exposure times to produce erythema were obtained, these being of higher value to the previous. The results show that it is difficult to obtain the recommended vitamin D doses in winter in a northern mid-latitude, as the human body is almost entirely covered in this season.

The determination of a band factor to express irradiance of UV and PAR wavelength ranges in a clean and dry atmosphere at Valencia, Spain

SYNOPSIS A new parameter called Band Factor (TB) is proposed to express the solar radiation of bands (wavelength ranges) in relation to a Clean and Dry Atmosphere (CDA). The determination of this factor will allow the identification, from band measurements, of atmospheric characteristics at the measured instant. To determine the TB of four bands, the optical depth of a CDA was parameterised versus the relative optical air mass, for the bands of the solar spectrum with ranges 280–315 nm, 290–380 nm, 315–400 nm and 400–700 nm. These bands greatly influence human, animal and plant life. A simple method to calculate direct normal band irradiance using available global horizontal band measurements is shown by way of an initial determination of TB for two bands carried out over a period of several years in Valencia, Spain.

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′Eclairages (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.

Personal UV exposure for different outdoor sports

Exposure to ultraviolet (UV) radiation is a major environmental risk factor in the development of skin cancers and it occurs mainly during outdoor activities. The purpose of this study is to quantify the UV exposure suffered by amateur athletes (tennis players, hikers and runners) in their training schedules. The study on tennis player exposure took place at a tennis club in Valencia during the month of June 2011. With respect to the hiking group, the hikes studied took place in several mountainous areas of Spain and France from June to August 2011. Finally, the exposure suffered by ten runners while participating in a running circuit in the province of Valencia, from March to November 2011, was studied. The athletes were monitored using personal dosimeters (VioSpor), with the tennis players and runners wearing them on the wrist and the hikers on the shoulder. The median daily personal UV exposure for the hikers was 8.1 Standard Erythema Dose (SED) and for the tennis players 7.5 SED per day of training. The runners received a median of 14.6 SED while participating in the running circuit and about 2 SED per competition day. Median daily UV exposure of the hikers and tennis players exceeded 5 SED, which means that, in the case of non-sun-adapted skin type III and the non-use of sun protection, erythema may be induced in these subjects. However, the exposure suffered by the runners did not exceed the maximum personal exposure of 5 SED. Accordingly, it is necessary to encourage the use of high protection sunscreens and protective clothing and to avoid UV exposure in the hottest part of the day.

Effect of the relative optical air mass and the clearness index on solar erythemal UV irradiance

This paper analyses the effects of the clearness index (Kt) and the relative optical air mass (mr) on erythemal UV irradiance (UVER). The UVER measurements were made in Valencia (Spain) from 6:00 am to 6:00 pm between June 2003 and December 2012 and (140,000 data points). Firstly, two models were used to calculate values for the erythemal ultraviolet irradiance clearness index (KtUVER) as a function of the global irradiance clearness index (Kt). Secondly, a potential regression model to measure the KtUVER as a function of the relative optical air mass was studied. The coefficients of this regression were evaluated for clear and cloudy days, as well as for days with high and low ozone levels. Thirdly, an analysis was made of the relationship between the two effects in the experimental database, with it being found that the highest degree of agreement, or the joint highest frequencies, are located in the optical mass range mr∈[1.0, 1.2] and the clearness index range of Kt∈[0.8, 1.0]. This is useful for establishing the ranges of parameters where models are more efficient. Simple equations have been tested that can provide additional information for the engineering projects concerning thermal installations. Fourthly, a high dispersion of radiation data was observed for intermediate values of the clearness for UV and UVER.

Contribution of sun exposure to the vitamin D dose received by various groups of the Spanish population

Although the harmful effects of excessive exposure to solar ultraviolet (UV) radiation are well known, the recommended dose of UV radiation is beneficial for the synthesis of vitamin D by the skin, in addition to being useful in the treatment of various illnesses and mental problems. Numerous studies have shown that vitamin D performs important functions in the human organism, such as absorbing calcium and phosphorous and contributing to the immune system, among others. Several studies have found that a high percentage of various groups of the Spanish population suffer from vitamin D deficiency, and since very few natural foods contain vitamin D, it was considered important to determine whether groups such as schoolchildren, outdoor workers and athletes, receive enough solar radiation to produce adequate levels of vitamin D in their daily activities. It was found that the amount of vitamin D (in IU) produced by personal effective solar UV doses could exceed the recommended dose of 1000IU/day in spring and summer, while the winter estimate (about 220IU/day) is only one quarter of the recommended dose. These results suggest that most people would not receive the recommended daily vitamin D dose in winter from exposure to solar UV radiation, the main source of vitamin D.