In Vivo Cutaneous and Perceived Comfort Response to Fabric: Part VI: The Effect of Moist Fabrics on Stratum Corneum Hydration

Materials placed over human skin may change the stratum corneum (sc) hydration level, an important phenomenon because increases in normal levels of sc hydration pose potential health problems. This study examines the relationship between fabric moisture content and level of sc hydration so that the role of fabric moisture on sc hydration may be better understood. Three fabric/moisture treatments are placed on the sc—3.5-denier polyester fabric with an initial moisture content of 35% and cotton fabrics with either 44% or 75% initial moisture content—then covered with an occlusive dome. sc evaporative water loss (ewl) is measured before treatment placement and after 30 and 60 minutes of contact. The amount of moisture in the fabric at time of removal is calculated two different ways, and three analyses of variance are done using the evaporative water loss and two fabric final moisture content data sets. The rate of ewl is significantly higher after 30 minutes of treatment contact with sc than after 60 minutes of contact. The amount of moisture in the fabrics is significantly less at time 60 than at time 30, implying that the sc is more hydrated at 30 minutes than at 60 minutes. However, the fabrics contain less moisture when removed at 60 minutes than at 30 minutes. As fabric moisture content decreases, sc hydration decreases. The question we are not able to answer is “Where does the moisture go that is initially in the fabric?’

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In Vivo Cutaneous Response to Fabric Part V: Effect of Fiber Type and Fabric Moisture Content on Stratum Corneum Hydration

Textile Research Journal ◽

10.1177/004051759206201103 ◽

1992 ◽

Vol 62 (11) ◽

pp. 638-647 ◽

Cited By ~ 18

Author(s):

Kathryn L. Hatch ◽

Nancy L. Markee ◽

Harriet H. Prato ◽

S. Haig Zeronian ◽

Howard I. Maibach ◽

...

Keyword(s):

Moisture Content ◽

Stratum Corneum ◽

Cotton Fabric ◽

Fiber Type ◽

Normal Skin ◽

Polyester Fabric ◽

Evaporative Water ◽

Potential Health ◽

Stratum Corneum Hydration

Fabric placed over human skin may change the stratum corneum (SC) hydration level, an important phenomenon because increases in normal levels of SC hydration pose potential health problems. The skin becomes more susceptible to abrasive damage, increases in permeability, and is more prone to microbial growth. The purpose of this study was to determine the effect of fiber type and fabric moisture content on SC hydration. Using three similarly constructed knit fabrics, six fabric type/moisture content combinations were selected for the tests. Using an occluded plastic dome, fabric samples were placed on both “normal” and “hydrated” volar forearm skin of subjects for a specified time period, then removed. Two minutes after removal, evaporative water loss and skin temperature were measured. The design of the study was a randomized complete block with all possible treatment combinations applied to each subject. Data were analyzed using analyses of variance on the linear and quadratic coefficients of best fit lines and Bonferroni t tests. For “normal” skin, SC hydration generally increased as fabric moisture content increased. The SC was significantly drier after being in contact with cotton fabric at regain than at the two moisture content levels above regain, and also under polyester fabric. For hydrated skin, the hydration state was significantly lower under the cotton fabric at regain than at 38.6% moisture content and at saturation, but was not significantly different under the polyester fabric at regain and at saturation.

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Water turnover and the northern range of the koala (Phascolarctos cinereus).

Australian Mammalogy ◽

10.1071/am07010 ◽

2007 ◽

Vol 29 (1) ◽

pp. 85 ◽

Cited By ~ 14

Author(s):

I.D. Clifton ◽

W.A.H. Ellis ◽

A. Melzer ◽

G. Tucker

Keyword(s):

Relative Humidity ◽

Moisture Content ◽

Water Loss ◽

Evaporative Water Loss ◽

Water Requirements ◽

Water Turnover ◽

Evaporative Water ◽

Phascolarctos Cinereus ◽

Energy Demands ◽

Cooling Mechanism

Water turnover for koalas is positively correlated with the moisture content of selected trees suggesting that browse choice was driven by water requirements in summer but energy demands in winter. We compared the distribution of the koala to relative humidity and found that the bioregional delineation of the koala?s range corresponds closely to regions experiencing an average 9am relative humidity of less than 80% in February. This indicates that the northern coastal distribution of the koala may be limited by respiratory evaporative water loss as a cooling mechanism.

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Evaporative water loss and the role of cocoon formation in Australian frogs

Australian Journal of Zoology ◽

10.1071/zo98013 ◽

1998 ◽

Vol 46 (5) ◽

pp. 405 ◽

Cited By ~ 28

Author(s):

Philip C. Withers

Keyword(s):

Water Content ◽

Water Loss ◽

High Water ◽

Linear Increase ◽

Evaporative Water Loss ◽

High Water Content ◽

Evaporative Water ◽

Wide Range ◽

Very High

Measurements of evaporative water loss (EWL; mg min-1) and resistance (R; sec cm-1) for various Australian frogs indicate three general allometric patterns: non-cocooned and non-‘waterproof’ frogs with EWL ∝ Mass0.30 and R independent of body mass at about 1–3 sec cm-1, cocooned frogs with EWL reduced about 50–200-fold and R about 50–200 sec cm-1, and ‘waterproof’ frogs with EWL reduced about 5–100- fold and R about 5–100 sec cm-1. Cocooned frogs have an exponential reduction in EWL and fairly linear increase in R over time, corresponding to the temporal addition of layers to the cocoon. The biophysical properties of cocoon are generally similar for various species, although there is some variation in both resistance per thickness (5–20 × 104 s cm-2) and diffusion coefficient (0.4–2.4 × 10 –5 cm2 s-1). The hygroscopic property of frog cocoon resembles that of mammalian stratum corneum, hair and wool, and mucopolysaccharides; there is a slight increase in water content of cocoon over a wide range of humidities but a very steep increase in water content and substantial hydration and swelling at >96% RH. This extreme hygroscopic behaviour of frog cocoon at very high RH may reflect less polymer cross-linking in frog cocoon and its high digestibility. The prevention of over-hydration of frog cocoon in vivo may be attributed to the restriction of high water content to only very high RH (>96%).

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