Division of Environmental Health Sciences, University of Minnesota School of Public Health, Minneapolis, Minnesota, USA.
Insight Exposure and Risk Sciences, Boulder, CO, USA.
Ann Work Expo Health. 2022 Aug 7;66(7):907-922. doi: 10.1093/annweh/wxac023.
Skin hydration and the barrier properties of the stratum corneum have been reported to be influential factors in the potential for retention of solid and semi-solid substances on the skin surface. The measurement of these characteristics of the skin, however, remains relatively uncommon in exposure assessments performed by industrial or occupational hygienists, even when the focus of the assessment is exposure to the skin. This study provides measurements of skin hydration using multiple instruments and multiple relevant skin site locations for comparative analysis. Three different measurement metrics, trans-epidermal water loss (TEWL), hydration index (HI), and percent hydration, were measured for 25 healthy volunteers at two different body locations for comparison: the center of the volar forearm, as previously recommended for interindividual comparison of hydration and barrier property measurements, and also the palmar tip of the index finger. The purpose of the comparative measurements was to allow for comparison between other published baseline volar forearm measurements and the palmar skin, which has not often been quantitatively assessed and reported in the literature, but is a relevant skin surface for sampling of the hands. This comparison will allow for consideration of the potential influence of palmar wipe sampling protocols on TEWL or skin hydration, and for the evaluation of the influence of skin hydration and TEWL on measured dermal transfer values. Collectively, the skin hydration levels and barrier properties at these two different measurement locations were found to be statistically significantly different, and as a result it is suggested that they be measured and recorded separately. Both measurement types and locations are likely to be important for the purposes of establishing skin hydration and health. Volar forearm measurements can also be important for understanding the underlying condition and barrier function of the skin, and palmar index finger measurements are necessary to understand the influence of both TEWL and skin hydration on quantitative dermal loading and transfer of solids and semi-volatile materials.
皮肤水合作用和角质层的屏障特性据报道是影响固体和半固体物质在皮肤表面滞留潜力的因素。然而，即使评估的重点是皮肤暴露，工业或职业卫生学家在进行暴露评估时，皮肤这些特性的测量仍然相对不常见。本研究使用多种仪器和多个相关皮肤部位位置进行测量，提供了皮肤水合作用的测量结果，用于比较分析。对于 25 名健康志愿者，在两个不同的身体部位（先前推荐用于个体间比较水合作用和屏障特性测量的掌侧前臂中部，以及食指的掌心尖端）测量了三种不同的测量指标：经表皮水分损失（TEWL）、水合指数（HI）和水合百分比。比较测量的目的是允许在其他已发表的掌侧前臂测量值和手掌皮肤之间进行比较，手掌皮肤在文献中经常没有进行定量评估和报告，但它是手部采样的相关皮肤表面。这种比较将允许考虑手掌擦拭采样方案对 TEWL 或皮肤水合作用的潜在影响，以及评估皮肤水合作用和 TEWL 对测量的皮肤转移值的影响。总的来说，这两个不同测量位置的皮肤水合水平和屏障特性在统计学上有显著差异，因此建议分别测量和记录。这两种测量类型和位置都可能对确定皮肤水合作用和健康状况很重要。掌侧前臂测量对于了解皮肤的潜在状况和屏障功能也很重要，而食指掌心测量对于理解 TEWL 和皮肤水合作用对固体和半挥发性物质的定量皮肤负荷和转移的影响是必要的。
