Vitamin D insufficiency in south-east Queensland.
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Adolescent↗
Biomedical subjects
A V Parisi
Publications and source records attributed to A V Parisi.
Comparison between seasons of the ultraviolet environment in the shade of trees in Australia.
BACKGROUND/PURPOSE: This paper has considered the erythemal UV (UVery), UVA and visible irradiances in the shade of Australian trees for each season at a sub-tropical southern hemisphere site. METHODS: The irradiances in tree shade have been measured with radiometers as a percentage of the irradiances in the sun for each season of the year. RESULTS: Although the solar irradiances are lower in winter, the percentages of the UV in tree shade compared to the UV in full sun are marginally higher (by up to 7%) in the winter compared to summer. The range of percentages for UVery was up to double that of the percentages of the visible waveband. The percentages for UVery were also higher than for the UVA waveband. The percentages of the irradiances in the tree shade compared to full sun are 8-14% lower at noon compared to the morning and afternoon for the UVery waveband. The ratio of UVA to UVery is lower in the tree shade compared to the full sun. CONCLUSIONS: The UVA to UVery ratio is expected to be even lower in the tree shade as a result of ozone depletion. This, combined with the visible irradiances in the tree shade not being a reliable indication of the biologically damaging UV irradiances, has consequences for public health and skin cancer prevention.
Australia↗
Solar ultraviolet exposures at ground level in tree shade during summer in south east Queensland.
Data are presented on the effect of the tree canopy transmittance in the visible waveband (VT), canopy width, height and height of the start of the tree canopy (CH) on the solar UV in tree shade on a horizontal plane at ground level during a Southern Hemisphere summer. Of these factors, the VT and CH have an influence on the UV irradiances in the tree shade. The shade ratios (UV in tree shade to that in full sun) for erythemal UV ranged from 0.71 to 0.42, 0.54 to 0.29 and 0.63 to 0.41 for morning, noon and afternoon, respectively, for the VT range of 0.4-1.0. Over the same VT range, the shade ratios for UVA ranged from 0.61 to 0.28, 0.50 to 0.22 and 0.49 to 0.29 for morning, noon and afternoon, respectively. The UV exposures in the tree shade decreased with the VT with a marginally higher decrease in the irradiances for the UVA compared to the erythemal UV. Despite the protection by the tree shade, significant UV in the tree shade of approximately 4 MED (minimum erythemal dose) were received for the latitude in this research on a cloud free summer day on a horizontal plane over a 2-h period centred about solar noon.
Environmental Exposure↗
Diffuse solar UV radiation and implications for preventing human eye damage.
Ocular UV exposure is a function of both the direct and diffuse components of solar radiation. Broadband global and diffuse UV measurements were made in the morning, noon and afternoon. Thirty sets of measurements were made in summer and 50 in each of the other seasons at each of the periods in full sun. Corresponding sets were made in the shade of Australian evergreen trees: 42 trees in summer and 50 in each of the other seasons. The percentage diffuse UV was higher for the shorter 320-400 nm range (UVB) than for 280-320 nm (UVA). The percentage diffuse UVB ranged from 23 to 59%, whereas the percentage diffuse UVA ranged from 17 to 31%. The percentage diffuse UV was lower at noon than in the morning and afternoon with the difference more pronounced for the UVB. The average percentage diffuse UVB over all the measurements in the tree shade for the morning, noon and afternoon was 62, 58 and 71%, respectively, and the average percentage diffuse UVA was 52, 51 and 59%, respectively.
Australia↗
Effect of cloud on UVA and exposure to humans.
The daily autumn and winter ultraviolet-A (320-400 nm) (UVA) exposures and 6 min UVA irradiance data for a southern hemisphere subtropical site (Toowoomba, Australia, 27.6 degrees S, 151.9 degrees E) are presented. This data is used to quantify the effect of cloud on UVA using an integrated sky camera and radiation system. Additionally, an estimate of the effect of enhanced UVA exposure on humans is made. The measurement system consisted of broad-band visible-infrared and UVA sensors together with a sun tracking, wide-angle video camera. The mean daily June exposure was found to be 409 kJ m-2. Under the constraints of the uncertainty of both the UVA measurement system and clear-sky model, one case of enhanced UVA irradiance was found. Three cases of cloud enhancement of daily UVA exposure, approaching clear-sky levels, were also determined using a calculated clear-sky envelope. It was also determined that for a fulltime outdoor worker the additional UVA exposure could approach approximately that of one third of a full winter's day. For indoor workers with an outside lunch break of 12:00-1:00 P.M. the additional UVA exposure was on an average 6.9 kJ m-2 over three cloud-enhanced days. To the authors' knowledge this is the first paper to present some evidence of cloud-enhanced UVA human exposure.
Environmental Exposure↗
Diffuse component of solar ultraviolet radiation in tree shade.
The first set of quantitative data of diffuse erythemal UV and UV-A radiation in tree shade at a sub-tropical Southern Hemisphere latitude is presented. Over the summer, approximately 60% of the erythemal UV radiation in tree shade is due to the diffuse component. Similarly, approximately 56% of the UV-A radiation in tree shade is due to the diffuse component. In tree shade these diffuse UV percentages are relatively constant from the morning to noon to afternoon periods. In comparison, in full sun, there is a decrease in the percentage of diffuse UV from morning to noon to afternoon. The exposures to diffuse UV on a horizontal plane in tree shade between 9:00 EST and 15:00 EST are of the order of 4 MED (minimum erythemal dose) and 14 J cm(-2) for erythemal UV and UV-A, respectively. The high diffuse UV component in the shade may result in high UV exposures not only to unprotected parts of the body on a horizontal plane, but also in equally high UV irradiances to parts of the body, including the eyes and face, that are not UV protected.
Diffusion↗
An estimation of biological hazards due to solar radiation.
A spectrum evaluator based on four different dosimeter materials has been employed to estimate the spectral irradiances of solar radiation for exposed humans. The result is used to calculate the biologically effective irradiance using the erythemal action spectrum and a fish melanoma action spectrum. Measurements are made in winter at a sub-tropical site on the chest and shoulder of subjects during normal daily activities. Up to 95% of the total UV exposure received is in the UV-A waveband (320-400 nm). The UV-A waveband is found to contribute approximately 14% of the erythemal UV and 93% of the biologically effective UV for fish melanoma. Extrapolation to humans suggests that exposure to the UV-A band will contribute to photodamage in human skin during exposure to solar radiation.
Animals↗
Effect of childhood and adolescent ultraviolet exposures on cumulative exposure in South East Queensland schools.
Quantitative estimates of the childhood and adolescent erythemal ultraviolet (UV) exposure received in South East Queensland schools are provided in this paper for age groups 0 to 6, 7 to 12 and 13 to 19 years. For the neck, hand and lower arm, sites of high UV exposure that are generally not covered by clothing, 13 to 19 year olds received the highest exposure of the three age groups, followed by 7 to 12 year olds. Exposure for 13 to 19 year olds contributed up to 44% of cumulative exposure to 20 years of age, and exposures for the 7 to 12 year olds contributed up to 31%. If the annual UV exposure for these two age groups were reduced to the average of all the age groups, cumulative erythemal UV exposure from 0 to 20 years would be reduced by up to 16%. On the other hand, if mothers can protect their babies by reducing the level of annual exposure to 30% of the annual UV exposure of the 7 to 12 year olds for the first four years then cumulative exposure to UV to age 20 would be reduced by up to 19%. These data confirm the importance of targeting young age groups in public campaigns for sun protection.
Adolescent↗
Field-based measurements of personal erythemal ultraviolet exposure through a common summer garment.
The research in this paper quantifies the solar erythemal UV exposures to the skin through a common summer garment during outdoor activities. The erythemal exposures under the garment for the wet white garment exceeded a MED (minimum erythemal dose) at some anatomical sites in summer for a two-hour period. An erythemal exposure of 1.7 MED, in excess of the occupational limit for UV exposure, was measured under the white garment during swimming for a one-hour period. Clothing must form an important component of a UV protection strategy. However, it must be realised that total UV protection is not provided and significant UV exposures may be received beneath the garment, particularly for a white garment in the wet state. This re-enforces the necessity of a combination of several UV prevention strategies to minimise UV exposure.
Environmental Exposure↗
Personal exposure distribution of solar erythemal ultraviolet radiation in tree shade over summer.
The personal radiant exposure distribution of solar erythemal UV in tree shade for an upright posture was measured, with measurements over the whole summer for a total of 17 trees. For each tree, the personal radiant exposure distribution was measured for both the morning and afternoon periods. The exposure ratios averaged over all the trees and over the morning and afternoon periods ranged from 0.16 to 0.49 for the different anatomical sites. A numerical model was employed to estimate the UV radiant exposure to humans in tree shade over the entire summer. The body sites with the higher exposure ratios in the tree shade were the vertex of the head, shoulders and forearms with radiant exposures over the summer of 1300 MED to the vertex of the head and 1100 MED to the shoulders and forearms. These radiant exposures in the shade are substantially higher than the ambient erythemal UV measured in full sun on a horizontal plane over a full summer at a more temperate northern hemisphere latitude. The average radiant exposures per day to each anatomical site for a complete day in the tree shade ranged from 4.6 to 14.6 MED. This research has provided new data that is essential to quantify human UV exposure during outdoor activities.
Australia↗
Evaluation of differences in ultraviolet exposure during weekend and weekday activities.
The weekday UV exposures to anatomical sites were evaluated for outdoor workers, home workers, adolescents, indoor workers, school staff and students in south-east Queensland, Australia. Additionally, the UV exposures at weekends of school staff, school students, indoor workers and outdoor workers were evaluated. The weekday exposures per day ranged from 1.0 to 11.0 SED for winter to summer respectively. During spring, the ratios of the personal exposures divided by the ambient exposures at the weekend to the personal exposures divided by the ambient exposures on the weekdays to the neck, hand and left arm were at least 3.4, 2.0 and 0.67 for the indoor workers, school staff and students and outdoor workers respectively. The same ratios for the erythemal UV exposures over the year, estimated from the exposures on four days in each of the four seasons, were at least 2.3 for the school staff and at least 1.3 for the 13 to 19 year old school students. These results reinforce the importance of targeting prevention programmes to both weekend and weekday exposures.
Adolescent↗
Lifetime ultraviolet exposure estimates for selected population groups in south-east Queensland.
The lifetime erythemal UV exposures received by selected population groups in southeast Queensland from birth up to an age of 55 years have been quantitatively estimated. A representative sample of teachers and other school workers received (64 +/- 22) x 10(5) J m(-2) to the neck compared with (4.1 +/- 1.4) x 10(5) J m(-2) to the upper leg. A sample of indoor workers (bank officers, solicitors and psychologists) received approximately 2% less and a sample of outdoor workers (carpenters, tilers, electricians and labourers) received approximately 10% more to the neck than the school workers. These differences in erythemal UV exposures may influence the risk of non-melanoma skin cancer.
Adolescent↗
Ultraviolet radiation penetrating vehicle glass: a field based comparative study.
The solar UV transmitted through automobile glass was measured in the field in two cars using a spectroradiometer. The two cars were identical except that one of the cars had all of the windows (except the windshield) tinted. The measured spectral erythemal UV on a horizontal plane with the windows fully closed was reduced in the tinted car by a factor of 42 when compared with the erythemal UV measured in the untinted car. The ambient UVA irradiances at various locations within four different makes of car and a tractor were also measured with a broad band UVA handheld meter. The average normalized daily UVA exposure (measured with a broad band UVA meter) was 1.3 times higher in a large family sedan when compared with that in a small hatchback and the UVA exposure in a car with tinted windows was 3.8 times less than in a similar untinted car.
Glass↗
Comparison of the spectral biologically effective solar ultraviolet in adjacent tree shade and sun.
The solar spectral UVR irradiances in tree shade and sunlight have been measured in a sub-tropical southern hemisphere summer. The spectral data allowed the UVB and UVA irradiances and the biologically effective irradiances to be calculated for different harmful biological processes to human skin and eyes. The average of the ratio of the UVA to UVB irradiances was lower by 26% in the shade compared with the same ratio in the sun. The spectral shade ratio calculated as the ratio of the spectral biologically effective irradiances in the shade to those in the adjacent sun decreased with increasing wavelength for all of the trees. The decrease in the shade ratio was approximately 42% at 400 nm compared with the shade ratio at 300 nm. Despite the UVR protection provided by tree shade, the erythemal UVR exposure received in 1 h in the tree shade exceeded the occupational limit for UVR exposure.
Animals↗
Penetration of solar erythemal UV radiation in the shade of two common Australian trees.
The penetration of solar erythemal ultraviolet radiation has been measured in the shade of a gum (Eucalyptus sp.) and a she oak (Casaurina) tree, both on a horizontal plane and with polysulphone dosimeters to human anatomical sites. This has provided new data useful for protection strategies against harmful ultraviolet radiation. For larger solar zenith angles, the relative penetration of solar erythemal ultraviolet in the shade of the trees is higher. On a horizontal plane, at noon, in winter, the shade erythemal ultraviolet ranged from 44 to 55% of that in the sun whereas in spring it ranged from 29 to 37% of the irradiances in the sun. Similarly, at 9:00 EST and 15:00 EST, the shade erythemal ultraviolet in winter ranged from 51 to 81% of the irradiances in the sun whereas in spring and summer they ranged from 35 to 51% of the unshaded irradiances. The shade ratios for specific body sites provided by the shade of the two trees were 0.05 to 0.45 for the solar zenith angles in this research. The shade ratios ranged from 0.14 to 0.45 for the gum tree and from 0.05 to 0.28 for the she oak. The denser foliage of the she oak provided higher ultraviolet protection compared to that of the gum tree.
Australia↗
Effect of stretch on the ultraviolet spectral transmission of one type of commonly used clothing.
The spectral ultraviolet (UV) transmission through stockings was measured in field and laboratory based trials using a spectroradiometer. From these spectral UV measurements, the ultraviolet protection factor (UPF) was calculated. The UPF of stockings measured in the field was generally higher than that measured in the laboratory when using a quartz tungsten halogen light as the UV source. The UPF of 50 denier stockings decreased 868% when stretched 30% from their original size. Doctors recommending and patients using high denier stockings for patient photoprotection should be aware of the dramatic decrease in UPF when the stocking is in a stretched position, such as over a human leg.
Clothing↗
The facial distribution of erythemal ultraviolet exposure in south-east Queensland.
This paper presents a method for the evaluation of the distribution of the facial erythemal UV exposure and the erythemal UV exposure per unit area of the face using only eight dosimeters located on the vertex of the head, forehead, nose, chin, left and right ears and left and right cheeks. An overall picture of the parts of the face receiving high UV exposures is provided. The distribution of the erythemal UV exposure to the human face at a subtropical latitude was shown to change with time of year and with cloud cover. On two days with similar solar zenith angles, the ratio of the erythemal UV exposure to the nose compared with that on a horizontal plane changed from 0.47 to 0.84 with increased cloud cover. At the same time, the total erythemal exposure per unit area of the face dropped from 122 to 56 ml cm-2. Although the absolute exposures decreased, the nose received a relatively high exposure.
Erythema↗
Simultaneous comparison of the personal UV exposure of two human groups at different altitudes.
A simultaneous comparison of human exposure to solar ultraviolet radiation at two locations was performed to study the effect of environmental factors and human attitudes on personal ultraviolet exposure. The study took place on 29 October 1996 in Toowoomba (27.5 degrees S, 151.9 degrees E) and Brisbane (27.4 degrees S, 153.1 degrees E), Queensland, Australia. From the data collected by calibrated ambient ultraviolet monitoring stations located in Toowoomba and Brisbane, Toowoomba received 68% more UVA (320-400 nm) and 61% more UVB (280-320 nm) than Brisbane from 07:00 to 10:00 Australian Eastern Standard Time (EST). From 10:00 to 17:00 EST Toowoomba received 5% more UVA and 20% less UVB than Brisbane. High ambient ultraviolet levels recorded by ultraviolet stations were reinforced by measurement of the personal ultraviolet exposure of human subjects wearing polysulfone dosimeters. Contrary to the common belief that the ultraviolet exposure to the human body is higher near the beach (i.e., coastal areas) than the inland area, the average erythemal weighted ultraviolet exposure on the chest and shoulder of each subject in the inland city of Toowoomba (127 km to the west of Brisbane) was 30% higher than in the coastal city of Brisbane from 07:00 to 17:00 EST. Evidence is also presented to suggest a relationship between altitude, climatic conditions, the human attitude, and the level of personal exposure to ultraviolet radiation.
Altitude↗