Turnbull David J, Parisi Alfio V
Centre for Rural and Remote Area Health, University of Southern Queensland, Toowoomba, Queensland 4350, Australia.
Radiat Res. 2008 Mar;169(3):344-9. doi: 10.1667/RR1136.1.
Currently, there is a major gap in the knowledge that is needed to optimize the beneficial effects related to ultraviolet (UV) radiation at wavelengths that induce vitamin D(3) synthesis (UV(D3)) compared to reducing the biologically damaging overexposure to UV radiation. The aim of this study was to investigate the use of diffuse (radiation that is scattered from all directions) UV radiation to optimize exposures to UV(D3) radiation and maximize the reduction of exposure to UVA radiation. Data on global and diffuse solar UV-radiation spectra were collected at 10-min intervals in the Southern Hemisphere in the late spring and summer from 1 November 2006 to 28 February 2007. For a solar zenith angle (SZA) of approximately 5 degrees , the observed maximum UV(D3) irradiances were 0.80 W/m(2) and 0.46 W/m(2) for global and diffuse UV radiation, respectively. The observed maximum UVA irradiances were 79.0 W/m(2) and 36.2 W/m(2) for global and diffuse UV radiation, respectively. For diffuse UV radiation, the maximum ratio of vitamin D(3) to UVA radiation was 1.75% at a SZA of approximately 10 degrees , whereas the maximum ratio for global UV was 1.27% at 10 degrees . For SZAs of 25 degrees and less, more UV radiation is in the wavelength region contributing to vitamin D(3) synthesis (UV(D3)) than in the UVA region for diffuse UV radiation than for global UV radiation.
目前，在优化与诱导维生素D(3)合成的波长的紫外线（UV(D3)）相关的有益效果所需的知识方面，与减少紫外线的生物损伤性过度暴露相比，存在重大差距。本研究的目的是调查使用漫射紫外线（从各个方向散射的辐射）来优化UV(D3)辐射暴露，并最大限度地减少UVA辐射暴露。2006年11月1日至2007年2月28日晚春和夏季，在南半球每隔10分钟收集一次全球和漫射太阳紫外线辐射光谱数据。对于太阳天顶角（SZA）约为5度的情况，观测到的全球和漫射紫外线辐射的最大UV(D3)辐照度分别为0.80W/m²和0.46W/m²。观测到的全球和漫射紫外线辐射的最大UVA辐照度分别为79.0W/m²和36.2W/m²。对于漫射紫外线辐射，在SZA约为10度时，维生素D(3)与UVA辐射的最大比值为1.75%，而全球紫外线在10度时的最大比值为1.27%。对于25度及以下的SZA，漫射紫外线辐射在有助于维生素D(3)合成的波长区域（UV(D3)）中的紫外线辐射比全球紫外线辐射在UVA区域中的更多。
