We quantify the effects of prolonged exposure to water on the mechanical, compositional and structural degradation of human skin. This environmental exposure is associated with maceration and the pathogenesis of dermatitis, immersion foot syndrome, and trench foot. Uniaxial tensometry reveals that water immersion of isolated stratum corneum (SC) ranging in age across 27 to 87 years can notably stiffen the tissue and cause both reductions in plasticity and rupture energy when allowed to equilibrate to a high relative humidity. Subsequent water sorption studies reveal that water immersion induced decreases in plastic extensibility are caused by a reduction in the tissue’s ability to hold water. In turn, this retention decrease is caused by a depletion in both lipids and natural moisturising factors. Further scrutiny of SC mechanical properties further reveals a clear delineation around 70 years. Employing this age-based categorisation, we establish that the degradative impact of water immersion is greatest for SC aged over 70 years. Histological examinations of full-thickness skin further reveal that prolonged water immersion for 7 days causes epidermal delamination, SC cavitation, and degradation in dermal collagen integrity. Immersion of skin in water at colder temperatures however reduces this degradation.

我们量化了长时间暴露于水对人体皮肤的机械，组成和结构退化的影响。这种环境暴露与皮肤炎，浸润性足综合征和trench足的浸软和发病机理有关。单轴张力测定法表明，浸入年龄在27至87岁之间的孤立角质层（SC）的水浸显着使组织变硬，并且在平衡至高相对湿度时会导致可塑性降低和破裂能量降低。随后的吸水研究表明，水浸入引起的塑料可塑性降低是由组织的持水能力降低引起的。继而，这种保留减少是由脂质和天然保湿因子的消耗引起的。对SC力学性能的进一步检查进一步揭示了约70年的清晰轮廓。通过使用这种基于年龄的分类，我们可以确定，对于70岁以上的SC来说，浸水的降解影响最大。对全层皮肤的组织学检查进一步表明，长时间浸泡在水中7天会导致表皮分层，SC空化和真皮胶原完整性下降。然而，将皮肤浸入较冷温度的水中可减少这种降解。和真皮胶原蛋白完整性下降。然而，将皮肤浸入较冷温度的水中可减少这种降解。和真皮胶原蛋白完整性下降。然而，将皮肤浸入较冷温度的水中可减少这种降解。