Centre for Medical Radiation Physics, School of Physics, Faculty of Engineering and Information Sciences, University of Wollongong, Wollongong, NSW 2522, Australia.
Institute for Superconducting and Electronic Materials, Australian Institute for Innovative Materials, Innovation Campus, Squires Way, North Wollongong, NSW 2500, Australia.
J Photochem Photobiol B. 2022 May;230:112435. doi: 10.1016/j.jphotobiol.2022.112435. Epub 2022 Mar 26.
Discussion continues over various aspects of sunscreen science: regulation, test methods, sun protection factor (SPF), labelling claims, potentially harmful components, among others. In this paper the UV transmission properties of a number of commercial sunscreens have been determined at constant sunscreen film thickness under different local UV Index conditions. The data demonstrate difficulties facing the public and the sunscreen industry as a whole, even though SPF values and other data stated on the sunscreen packaging are assumed to be correct according to standard testing methods. This work has shown that at realistic application rates the critical factors are the intensity of the incident solar radiation and the accumulated erythema UV dose transmitted over time. In one example, on 'Extreme' UV Index days, an SPF 30 sunscreen under test transmitted one minimal erythema dose (MED) of UV in only 35 min. In another example, although it should not, in theory, transmit one MED until several hours of exposure, this level was reached in 1 h by an SPF 50 sunscreen under these typical Australian summer conditions (UV Index 12) in Wollongong, NSW (34.4°S). Such properties could have severe consequnces if these sunscreens were used by individuals with Fitzpatrick Skin Type 1, organ transplant recipients or other immuno-compromised individuals.
法规、测试方法、防晒因子（SPF）、标签声称、潜在有害成分等。本文在恒定的防晒霜膜厚下，根据不同的局部紫外线指数条件，测定了一些市售防晒霜的紫外线透过特性。这些数据表明，即使根据标准测试方法，假设防晒霜包装上的 SPF 值和其他数据是正确的，公众和整个防晒霜行业也面临着困难。这项工作表明，在实际应用率下，关键因素是入射太阳辐射的强度和随时间累积的红斑紫外线剂量。例如，在“极端”紫外线指数日，正在测试的 SPF30 防晒霜在 35 分钟内仅透过一个最小红斑剂量（MED）的紫外线。另一个例子是，尽管在理论上，防晒霜要在暴露数小时后才会达到一个 MED 水平，但在新南威尔士州卧龙岗（南纬 34.4°）典型的澳大利亚夏季条件（紫外线指数 12）下，SPF50 的防晒霜在 1 小时内就达到了这一水平。如果这些防晒霜被 1 型菲茨帕特里克皮肤类型的个体、器官移植受者或其他免疫功能低下的个体使用，这些特性可能会产生严重的后果。
