Biomedical subjects

A F Moise

Publications and source records attributed to A F Moise.

4 recordsLinked to original sources

PubMed1999

Ambient ultraviolet radiation levels in public shade settings.

As people become better informed about the harmful effects of prolonged exposure to solar ultraviolet radiation (UVR, 280-400 nm) they will seek the protection of shade, particularly in tropical locations such as Townsville (19 degrees south). Using broad-band radiation sensors for solar ultraviolet-B (280-315 nm), ultraviolet-A (315-400 nm) and daylight (400-800 nm) radiation, the exposure levels were measured in both the horizontal (shaded and unshaded) and vertical (shaded and unshaded) directions. The measurements were conducted at eight locations (shade settings) in Townsville during the period between December 1997 (summer) and May 1998 (beginning of winter). The quality of protection was assessed by the ratio of unshaded to shaded radiation exposure, the UVB/shade protection ratio (UVB-SPR). The UVB-SPR varies considerably between the different shade settings, with a beach umbrella showing the least protection and dense foliage the highest protection. The roof of a house verandah can provide only little protection if the verandah catches the afternoon sun. Increasing cloud cover decreases the UVB-SPR for all settings because of the increase in the diffuse fraction of the radiation. Only one setting provided a UVB-SPR of 15 or higher, as suggested for protective shading against solar UVB radiation. Shade from direct sunlight alone does not provide enough protection against high levels of solar UVR. Apart from the transmission qualities of the shading material, it is the construction of the whole shade setting that determines the exposure levels underneath. A shade structure with enough overhang is recommended so that high levels of scattered radiation do not reach the skin.

Humans↗

PubMed1999

Estimation of the annual solar UVR exposure dose of infants and small children in tropical Queensland, Australia.

The solar ultraviolet radiation (UVR) exposure of infants and small children was measured for 1 week using UVR-sensitive polysulfone film attached to the shoulder and chest of the subjects. For the infant study, shoulder and chest badges received similar exposures, while the 2 1/2-year-olds received higher exposures on the shoulder than on the chest. Also, the 2 1/2-year-olds generally received higher exposures than the infants. The median total daily exposures for both groups were 39 and 92 J/m2. The maximum total daily exposures measured were 640 J/m2 (chest) and 240 J/m2 (shoulder) for the infants and 2060 J/m2 (shoulder) and 840 J/m2 (chest) for the 2 1/2 year-olds. Using this exposure data, monthly and annual exposure doses were calculated for both groups and compared to similar data from the UK. The annual exposure dose for infants is 8.4 kJ/m2 or 84 standard erythemal dose (SED) for both shoulder and chest. The annual exposure dose for 2 1/2 year-old children is 39.4 kJ/m2 or 394 SED for the shoulder and 28.8 kJ/m2 or 288 SED for the chest. Apart from the generally higher annual exposure doses experienced by the infants and 2 1/2 year-old children in Townsville, the main difference to the UK is the almost nonexistent drop in monthly exposure doses between summer and winter in Townsville compared to the UK. In the UK, the winter-month exposure dose is only 0.5% of the summer-month dose. However, in Townsville it is around 40%.

Child, Preschool↗

PubMed1999

Sun exposure at school.

There is strong evidence that sun exposure during childhood and adolescence plays an important role in the etiology of skin cancer, in particular cutaneous melanoma. Between the age of 6 and 18, most children and adolescents will spend around 200 days per year at school and may receive a substantial fraction of their daily total solar ultraviolet radiation (UVR) exposure while at school. This study estimated the average daily erythemally effective dose of 70 grade 8 students from a high school in Townsville during 5 school days in July 1998. Through UV measurements of shade locations at the school and a combination of frequency counts and a questionnaire of grade 8 students, it was possible to determine the fraction of solar UVR reaching under the shade structures during lunch breaks and routine outdoor activities. Also, a routinely operating UV-Biometer provided the annual variation of the daily dose that was used to calculate exposure levels for the 70 students. Our results suggest that up to 47% of the daily total dose fell within the time periods where students were outdoors during school hours. For students not seeking shade structures during the breaks (which usually was the case when involved in sport activities such as basketball or soccer), the average daily dose could have been as high as 14 SED (standard erythemal dose). Using results from the questionnaire of 70 grade 8 students, their average annual dose while at school was 414 SED or 2 SED per school day. However, the distribution of average daily erythemal effective dose per grade 8 student over the whole year showed that on 31% of all school days in 1998, this dose was exceeded. Because most previous attempts to change arguably poor sun-protective behavior of young Australian children and adolescents at school showed little success, one way of decreasing the amount of harmful UVR reaching unprotected skin is the more careful design of shade structures at schools.

Adolescent↗

PubMedDate not supplied

Solar ultraviolet radiation exposure of infants and small children.

Townsville, in Queensland, Australia, experiences very high levels of ambient solar ultraviolet radiation (UVR) throughout the year and has a predominantly white population which is prone to developing skin cancer. The UVR exposure of 1-year-old and 2 1/2-year-old children raised in Townsville was measured using UVR-sensitive polysulphone film badges. In two separate exposure studies undertaken for 7 days in October 1995 and 5 days in April 1997, exposure at the chest and shoulder for each subject was determined. The chest exposures for the 1-year-olds were significantly higher at weekends than on weekdays, whereas for the 2 1/2-year-old children the shoulder exposures were significantly higher at weekends than on weekdays. The median daily total exposure for 1-year-old infants was 0.4 SED (standard erythemal dose) for the chest and 0.4 SED for the shoulder. The median daily total exposure for 2 1/2-year-olds was 0.6 SED for the chest and 0.9 SED for the shoulder. Although the median daily total exposures were comparatively low, the maximum values for the chest and shoulder were 6.5 SED and 2.4 SED, respectively, for the 1-year-old infants, and 20.6 SED and 8.4 SED, respectively, for the 2 1/2-year-olds. While the 2 1/2-year-old children spent most of their time outside between 9 am and 4 pm, the 1-year-old infants spent more time outside before 9 am and after 4 pm. Exposure increases with age in early childhood. Increased mobility and a greater tendency to play outdoors is likely to account for the higher exposure levels in 2 1/2-year-old children, compared to 1-year-old infants.

Child, Preschool↗