Cumulative Irritation in Older and Younger Skin: a Comparison

Abstract

Changes in stratum corneum properties due to sodium lauryl sulfate cumulative irritation were determined as a function of age. We irritated the backs of 7 younger (27.7 +/- 4.6 years, mean +/- standard deviation) and 10 older (69.8 +/- 5.5 years) volunteers on 5 consecutive days with open application of a 7.5% aqueous sodium lauryl sulfate solution. Water- and untreated skin served as controls. Transepidermal water loss, stratum corneum capacitance, Desquamation Index, and skin roughness parameters were evaluated on 5 days of the 1st week, and on 3 days of the 2nd week. All parameters revealed a delayed and decreased reaction of older compared to younger skin and recovery appeared to be prolonged. We conclude that under these test conditions irritancy to repetitive sodium lauryl sulfate exposure of older versus younger skin resembled that previously observed after single occlusive exposure. In neither age group was the recovery effect reduced by repeated irritation, demonstrating sufficient skin barrier and recovery function.

Prevalence of and Risk Factors for Skin Diseases Among Army Personnel and Flood Victims During the 2011 Floods in Thailand

“…[10][11][12] However, other endogenous factors including age and sex showed no association with skin symptoms. Although other studies indicated that the younger age group is more susceptible to irritants, 13,14 our study showed a similarly high prevalence of skin symptoms in all age groups except the ages of 20 to 29 years. This could be explained by the fact that the majority of this age group were army personnel (82.0%).…”

Self-adhesive epidermal carbon nanotube electronics for tether-free long-term continuous recording of biosignals

“…2c). It was found that CNT/aPDMS has much lower modulus (27.5 kPa) than PDMS (~1 MPa); this value is comparable to that of skin (130 kPa)2526. This low modulus enhances the mechanical matching of the large electrode to soft skin and increases its ability to penetrate skin wrinkles.…”

Skin Surface Topography and Texture Analysis of Sun-Exposed Body Sites in View of Sunscreen Application

“…Although fast and convenient direct methods that are appropriate for the clinical setting have been developed based on interference fringe profilometry and the use of CCD cameras [26,27,28], the preparation of replicas remains the most frequently used technique with a vast body of data available [3,4,5,8,10,12,13,17,18,29,30,31]. The advantages of the replica technique are simple and rapid sample preparation, reproducibility and precision, and the possibility to store the replica for repeated measurements [24,25].…”

“…Roughness was reported to vary significantly between different sites, being largest in the posterior neck and smallest in the upper back and lower leg, while only minor differences between genders and races were shown [8,9]. Surface topography was further used to assess the results of intervention on skin, for example, by moisturizing agents [10], antiaging products [6], laser surgery [11], chemical irritants [12], and vitamin analogs [13]. …”