Godar Dianne E, Urbach Frederick, Gasparro Francis P, van der Leun Jan C
Radiation Biology Branch, U.S. Food and Drug Administration, Center for Devices and Radiological Health, Rockville, MD 20852, USA.
Photochem Photobiol. 2003 Apr;77(4):453-7. doi: 10.1562/0031-8655(2003)077<0453:udoya>2.0.co;2.
Since 1986, people have been informed that they get about 80% of their lifetime ultraviolet (UV) dose by the age of 18. This belief originated from the mathematical conclusion that diligent use of sunscreens (sun protection factor 15 or higher) during the first 18 years of life would reduce the lifetime incidence of nonmelanoma skin cancers by 78%. These data were misconstrued to mean that individuals also got about 80% of their lifetime dose of UV by the age of 18 (linear relationship). However, these calculations were based on the incidence of nonmelanoma skin cancers being related to the square of the UV dose. Careful analysis of UV exposure data shows that Americans actually get less than 25% of their lifetime UV dose by the age of 18. This finding also appears to be true worldwide because Australia, UK and The Netherlands report a similar UV exposure pattern. UV-initiated damage early in life can be promoted by subsequent exposures to progress into tumors later in life. For example, the nonmelanoma skin cancer, squamous cell carcinoma, is dependent on the cumulative UV dose. Thus, a better educational approach for reducing skin cancers would be to instruct fair-skinned individuals to protect themselves throughout their lives from being exposed to too much UV radiation.
自1986年以来,人们一直被告知,到18岁时,他们一生中约80%的紫外线(UV)剂量已经累积。这一观点源于数学结论:在生命的前18年中,勤勉使用防晒霜(防晒系数为15或更高)可使非黑色素瘤皮肤癌的终生发病率降低78%。这些数据被误解为个体在18岁时也获得了约80%的终生紫外线剂量(线性关系)。然而,这些计算是基于非黑色素瘤皮肤癌的发病率与紫外线剂量的平方相关。对紫外线暴露数据的仔细分析表明,美国人在18岁时实际获得的紫外线剂量不到其终生剂量的25%。这一发现似乎在全球范围内都是如此,因为澳大利亚、英国和荷兰报告了类似的紫外线暴露模式。生命早期由紫外线引发的损伤会因随后的暴露而加剧,进而在生命后期发展为肿瘤。例如,非黑色素瘤皮肤癌——鳞状细胞癌,就取决于累积的紫外线剂量。因此,减少皮肤癌的更好教育方法是指导皮肤白皙的人终生保护自己,避免暴露于过多的紫外线辐射。